2000-04-27 22:03:57 +02:00
\input texinfo @c -*-texinfo-*-
@c %**start of header
@setfilename ngspice.info
@settitle SPICE User Manual
@setchapternewpage odd
@c %**end of header
@ifinfo
This file documents SPICE.
Copyright 1996 The Regents of the University of California.
Permission to use, copy, modify, and distribute this software and its
documentation for educational, research and non-profit purposes,
without fee, and without a written agreement is hereby granted,
provided that the above copyright notice, this paragraph and the
following three paragraphs appear in all copies.
This software program and documentation are copyrighted by The Regents
of the University of California. The software program and
documentation are supplied "as is", without any accompanying services
from The Regents. The Regents does not warrant that the operation of
the program will be uninterrupted or error-free. The end-user
understands that the program was developed for research purposes and
is advised not to rely exclusively on the program for any reason.
IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY
FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES,
INCLUDING LOST PROFITS, ARISING OUT OF THE USE OF THIS SOFTWARE AND
ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF CALIFORNIA HAS BEEN
ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. THE UNIVERSITY OF
CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS ON AN "AS IS"
BASIS, AND THE UNIVERSITY OF CALIFORNIA HAS NO OBLIGATIONS TO PROVIDE
MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
@end ifinfo
@c This title page illustrates only one of the
@c two methods of forming a title page.
@titlepage
@title SPICE User Manual
@c @subtitle SUBTITLE-IF-ANY
@c @subtitle SECOND-SUBTITLE
@author
@c The following two commands
@c start the copyright page.
@page
@vskip 0pt plus 1filll
Copyright 1996 The Regents of the University of California.
@c Published by ...
Permission to use, copy, modify, and distribute this software and its
documentation for educational, research and non-profit purposes,
without fee, and without a written agreement is hereby granted,
provided that the above copyright notice, this paragraph and the
following three paragraphs appear in all copies.
This software program and documentation are copyrighted by The Regents
of the University of California. The software program and
documentation are supplied "as is", without any accompanying services
from The Regents. The Regents does not warrant that the operation of
the program will be uninterrupted or error-free. The end-user
understands that the program was developed for research purposes and
is advised not to rely exclusively on the program for any reason.
IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY
FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES,
INCLUDING LOST PROFITS, ARISING OUT OF THE USE OF THIS SOFTWARE AND
ITS DOCUMENTATION, EVEN IF THE UNIVERSITY OF CALIFORNIA HAS BEEN
ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. THE UNIVERSITY OF
CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS ON AN "AS IS"
BASIS, AND THE UNIVERSITY OF CALIFORNIA HAS NO OBLIGATIONS TO PROVIDE
MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
@end titlepage
@node Top, Introduction, (dir), (dir)
@ifinfo
This document describes ...
This document applies to version ...
of the program named ...
@end ifinfo
@menu
* Introduction::
* Circuit Description::
* Circuit Elements and Models::
* Analyses and Output Control::
* Interactive Interpreter::
* Bibliography::
* Example Circuits::
* Model and Device Parameters::
@end menu
@c @node First Chapter, Second Chapter, top, top
@c @comment node-name, next, previous, up
@c @chapter First Chapter
@c @cindex Index entry for First Chapter
@node Introduction, Circuit Description, Top, Top
@comment node-name, next, previous, up
@chapter Introduction
SPICE is a general-purpose circuit simulation program for nonlinear
dc, nonlinear transient, and linear ac analyses. Circuits may contain
resistors, capacitors, inductors, mutual inductors, independent
voltage and current sources, four types of dependent sources, lossless
and lossy transmission lines (two separate implementations), switches,
uniform distributed RC lines, and the five most common semiconductor
devices: diodes, BJTs, JFETs, MESFETs, and MOSFETs.
The SPICE3 version is based directly on SPICE 2G.6. While SPICE3 is
being developed to include new features, it continues to support those
capabilities and models which remain in extensive use in the SPICE2
program.
SPICE has built-in models for the semiconductor devices, and the user
need specify only the pertinent model parameter values. The model for
the BJT is based on the integral-charge model of Gummel and Poon;
however, if the Gummel- Poon parameters are not specified, the model
reduces to the simpler Ebers-Moll model. In either case,
chargestorage effects, ohmic resistances, and a current-dependent
output conductance may be included. The diode model can be used for
either junction diodes or Schottky barrier diodes. The JFET model is
based on the FET model of Shichman and Hodges. Six MOSFET models are
implemented: MOS1 is described by a square-law I-V characteristic,
MOS2 [1] is an analytical model, while MOS3 [1] is a semi-empirical
model; MOS6 [2] is a simple analytic model accurate in the
shortchannel region; MOS4 [3, 4] and MOS5 [5] are the BSIM (Berkeley
Short-channel IGFET Model) and BSIM2. MOS2, MOS3, and MOS4 include
second-order effects such as channel-length modulation, subthreshold
conduction, scattering-limited velocity saturation, small-size
effects, and chargecontrolled capacitances.
@menu
* Types of Analysis::
* Analysis at Different Temperatures::
* Convergence::
@end menu
@node Types of Analysis, Analysis at Different Temperatures, Introduction, Introduction
@section Types of Analysis
@menu
* DC Analysis::
* AC Small-Signal Analysis::
* Transient Analysis::
* Pole-Zero Analysis::
* Small-Signal Distortion Analysis::
* Sensitivity Analysis::
* Noise Analysis::
@end menu
@node DC Analysis, AC Small-Signal Analysis, Types of Analysis, Types of Analysis
@subsection DC Analysis
The dc analysis portion of SPICE determines the dc operating point of
the circuit with inductors shorted and capacitors opened. The dc
analysis options are specified on the .DC, .TF, and .OP control lines.
A dc analysis is automatically performed prior to a transient analysis
to determine the transient initial conditions, and prior to an ac
small-signal analysis to determine the linearized, small-signal models
for nonlinear devices. If requested, the dc small-signal value of a
transfer function (ratio of output variable to input source), input
resistance, and output resistance is also computed as a part of the dc
solution. The dc analysis can also be used to generate dc transfer
curves: a specified independent voltage or current source is stepped
over a user-specified range and the dc output variables are stored for
each sequential source value.
@node AC Small-Signal Analysis, Transient Analysis, DC Analysis, Types of Analysis
@subsection AC Small-Signal Analysis
The ac small-signal portion of SPICE computes the ac output variables
as a function of frequency. The program first computes the dc
operating point of the circuit and determines linearized, small-signal
models for all of the nonlinear devices in the circuit. The resultant
linear circuit is then analyzed over a user-specified range of
frequencies. The desired output of an ac small-signal analysis is
usually a transfer function (voltage gain, transimpedance, etc). If
the circuit has only one ac input, it is convenient to set that input
to unity and zero phase, so that output variables have the same value
as the transfer function of the output variable with respect to the
input.
@node Transient Analysis, Pole-Zero Analysis, AC Small-Signal Analysis, Types of Analysis
@subsection Transient Analysis
The transient analysis portion of SPICE computes the transient output
variables as a function of time over a user-specified time interval.
The initial conditions are automatically determined by a dc analysis.
All sources which are not time dependent (for example, power supplies)
are set to their dc value. The transient time interval is specified
on a .TRAN control line.
@node Pole-Zero Analysis, Small-Signal Distortion Analysis, Transient Analysis, Types of Analysis
@subsection Pole-Zero Analysis
The pole-zero analysis portion of SPICE computes the poles and/or
zeros in the small-signal ac transfer function. The program first
computes the dc operating point and then determines the linearized,
small-signal models for all the nonlinear devices in the circuit.
This circuit is then used to find the poles and zeros of the transfer
function.
Two types of transfer functions are allowed: one of the form (output
voltage)/(input voltage) and the other of the form (output
voltage)/(input current). These two types of transfer functions cover
all the cases and one can find the poles/zeros of functions like
input/output impedance and voltage gain. The input and output ports
are specified as two pairs of nodes.
The pole-zero analysis works with resistors, capacitors, inductors,
linear-controlled sources, independent sources, BJTs, MOSFETs, JFETs
and diodes. Transmission lines are not supported.
The method used in the analysis is a sub-optimal numerical search.
For large circuits it may take a considerable time or fail to find all
poles and zeros. For some circuits, the method becomes "lost" and
finds an excessive number of poles or zeros.
@node Small-Signal Distortion Analysis, Sensitivity Analysis, Pole-Zero Analysis, Types of Analysis
@subsection Small-Signal Distortion Analysis
The distortion analysis portion of SPICE computes steady-state
harmonic and intermodulation products for small input signal
magnitudes. If signals of a single frequency are specified as the
input to the circuit, the complex values of the second and third
harmonics are determined at every point in the circuit. If there are
signals of two frequencies input to the circuit, the analysis finds
out the complex values of the circuit variables at the sum and
difference of the input frequencies, and at the difference of the
smaller frequency from the second harmonic of the larger frequency.
Distortion analysis is supported for the following nonlinear devices:
diodes (DIO), BJT, JFET, MOSFETs (levels 1, 2, 3, 4/BSIM1, 5/BSIM2,
and 6) and MESFETS. All linear devices are automatically supported by
distortion analysis. If there are switches present in the circuit,
the analysis continues to be accurate provided the switches do not
change state under the small excitations used for distortion
calculations.
@node Sensitivity Analysis, Noise Analysis, Small-Signal Distortion Analysis, Types of Analysis
@subsection Sensitivity Analysis
Spice3 will calculate either the DC operating-point sensitivity or the
AC small-signal sensitivity of an output variable with respect to all
circuit variables, including model parameters. Spice calculates the
difference in an output variable (either a node voltage or a branch
current) by perturbing each parameter of each device independently.
Since the method is a numerical approximation, the results may
demonstrate second order affects in highly sensitive parameters, or
may fail to show very low but non-zero sensitivity. Further, since
each variable is perturb by a small fraction of its value, zero-valued
parameters are not analyized (this has the benefit of reducing what is
usually a very large amount of data).
@node Noise Analysis, , Sensitivity Analysis, Types of Analysis
@subsection Noise Analysis
The noise analysis portion of SPICE does analysis device-generated
noise for the given circuit. When provided with an input source and
an output port, the analysis calculates the noise contributions of
each device (and each noise generator within the device) to the output
port voltage. It also calculates the input noise to the circuit,
equivalent to the output noise referred to the specified input source.
This is done for every frequency point in a specified range - the
calculated value of the noise corresponds to the spectral density of
the circuit variable viewed as a stationary gaussian stochastic
process.
After calculating the spectral densities, noise analysis integrates
these values over the specified frequency range to arrive at the total
noise voltage/current (over this frequency range). This calculated
value corresponds to the variance of the circuit variable viewed as a
stationary gaussian process.
@node Analysis at Different Temperatures, Convergence, Types of Analysis, Introduction
@section Analysis at Different Temperatures
All input data for SPICE is assumed to have been measured at a nominal
temperature of 27<32> C, which can be changed by use of the TNOM
parameter on the .OPTION control line. This value can further be
overridden for any device which models temperature effects by
specifying the TNOM parameter on the model itself. The circuit
simulation is performed at a temperature of 27<32> C, unless
overridden by a TEMP parameter on the .OPTION control line.
Individual instances may further override the circuit temperature
through the specification of a TEMP parameter on the instance.
Temperature dependent support is provided for resistors, diodes,
JFETs, BJTs, and level 1, 2, and 3 MOSFETs. BSIM (levels 4 and 5)
MOSFETs have an alternate temperature dependency scheme which adjusts
all of the model parameters before input to SPICE. For details of the
BSIM temperature adjustment, see [6] and [7].
Temperature appears explicitly in the exponential terms of the BJT and
diode model equations. In addition, saturation currents have a
built-in temperature dependence. The temperature dependence of the
saturation current in the BJT models is determined by:
@tex
$$
I_S(T_1) = I_S(T_0) \left|T_1 \over T_0\right|^{XTI}
\exp \left| E_g q(T_1 T_0) \over k (T_1 - T_0) \right|
$$
@end tex
@ifnottex
@example
XTI
|T | | E q(T T )|
1 g 1 0
I (T ) = I (T ) |--| exp|-----------|
S 1 S 0
|T | |k (T - T )|
0 1 0
@end example
@end ifnottex
where k is Boltzmann's constant, q is the electronic charge, E is the
energy gap which is a model parameter, G and XTI is the saturation
current temperature exponent (also a model parameter, and usually
equal to 3).
The temperature dependence of forward and reverse beta is according to
the formula:
@tex
$$
B(T_1) = B(T_0) \left| T_1 \over T_0 \right|^{XTB}
$$
@end tex
@ifnottex
@example
XTB
|T |
1
B(T ) = B(T ) |--|
1 0
|T |
0
@end example
@end ifnottex
where T and T are in degrees Kelvin, and XTB is a user-supplied model
parameter. Temperature effects on beta are carried out by appropriate
adjustment to the values of B_F , I_SE , B_R , and I_SC (spice model
parameters BF, ISE, BR, and ISC, respectively).
Temperature dependence of the saturation current in the junction diode
model is determined by:
@tex
$$
I_S(T_1) = I_S(T_0) \left| T_1 \over T_0 \right|^{XTI \over N}
\exp \left| E_g q(T_1 T_0) \over N k (T_1 - T_0) \right|
$$
@end tex
@ifnottex
@example
XTI
---
N
|T | | E q(T T ) |
1 g 1 0
I (T ) = I (T ) |--| exp|-------------|
S 1 S 0
|T | |N k (T - T )|
0 1 0
@end example
@end ifnottex
where N is the emission coefficient, which is a model parameter, and the
other symbols have the same meaning as above. Note that for Schottky
barrier diodes, the value of the saturation current temperature
exponent, XTI, is usually 2.
Temperature appears explicitly in the value of junction potential, U
(in spice PHI), for all the device models. The temperature dependence
is determined by:
@tex
$$
U(T) = {k T \over q} \log_e \left| N_a N_d \over N_i T^2 \right|
$$
@end tex
@ifnottex
@example
| N N |
a d
kT |------ |
U(T) = -- log 2
q e |N (T) |
i
@end example
@end ifnottex
where k is Boltzmann's constant, q is the electronic charge, N_a is
the acceptor impurity density, N_d is the donor impurity density, N_i
is the intrinsic carrier con centration, and E_g is the energy gap.
Temperature appears explicitly in the value of surface mobility, M_0
(or UO), for the MOSFET model. The temperature dependence is
determined by:
@tex
$$
M_0(T) = {M_0(T_0) \over \left| T \over T_0 \right|^{1.5}}
$$
@end tex
@ifnottex
@example
M (T )
0 0
M (T) = -------
0 1.5
| T|
|--|
|T |
0
@end example
@end ifnottex
The effects of temperature on resistors is modeled by the formula:
@tex
$$
R(T) = R(T_0) \bigl( 1 + TC_1 (T - T_0) + TC_2 (T - T_0)^2 \bigr)
$$
@end tex
@ifnottex
@example
2
R(T) = R(T ) [1 + TC (T - T ) + TC (T - T ) ]
0 1 0 2 0
@end example
@end ifnottex
where T is the circuit temperature, T_0 is the nominal temperature,
and TC_1 and TC_2 are the first- and second order temperature
coefficients.
@node Convergence, , Analysis at Different Temperatures, Introduction
@section Convergence
Both dc and transient solutions are obtained by an iterative process
which is terminated when both of the following conditions hold:
@enumerate
@item
The nonlinear branch currents converge to within a tolerance of 0.1% or
1 picoamp (1.0e-12 Amp), whichever is larger.
@item
The node voltages converge to within a tolerance of 0.1% or 1 microvolt
(1.0e-6 Volt), whichever is larger.
@end enumerate
Although the algorithm used in SPICE has been found to be very
reliable, in some cases it fails to converge to a solution. When this
failure occurs, the program terminates the job.
Failure to converge in dc analysis is usually due to an error in
specifying circuit connections, element values, or model parameter
values. Regenerative switching circuits or circuits with positive
feedback probably will not converge in the dc analysis unless the OFF
option is used for some of the devices in the feedback path, or the
.NODESET control line is used to force the circuit to converge to the
desired state.
@node Circuit Description, Circuit Elements and Models, Introduction, Top
@chapter Circuit Description
@menu
* General Structure and Conventions::
* Basics::
* Device Models::
* Subcircuits::
* INCLUDE::
@end menu
@node General Structure and Conventions, Basics, Circuit Description, Circuit Description
@section General Structure and Conventions
The circuit to be analyzed is described to SPICE by a set of element
lines, which define the circuit topology and element values, and a set
of control lines, which define the model parameters and the run
controls. The first line in the input file must be the title, and the
last line must be ".END". The order of the remaining lines is
arbitrary (except, of course, that continuation lines must immediately
follow the line being continued).
Each element in the circuit is specified by an element line that
contains the element name, the circuit nodes to which the element is
connected, and the values of the parameters that determine the
electrical characteristics of the element. The first letter of the
element name specifies the element type. The format for the SPICE
element types is given in what follows. The strings XXXXXXX, YYYYYYY,
and ZZZZZZZ denote arbitrary alphanumeric strings. For example, a
resistor name must begin with the letter R and can contain one or more
characters. Hence, R, R1, RSE, ROUT, and R3AC2ZY are valid resistor
names. Details of each type of device are supplied in a following
section.
Fields on a line are separated by one or more blanks, a comma, an
equal ('=') sign, or a left or right parenthesis; extra spaces are
ignored. A line may be continued by entering a '+' (plus) in column 1
of the following line; SPICE continues reading beginning with column
2.
A name field must begin with a letter (A through Z) and cannot contain
any delimiters.
A number field may be an integer field (12, -44), a floating point
field (3.14159), either an integer or floating point number followed
by an integer exponent (1e-14, 2.65e3), or either an integer or a
floating point number followed by one of the following scale factors:
@c TODO: put this in multiple columns.
@ifnottex
@math{@code{T} = 10^12}
@math{@code{G} = 10^9}
@math{@code{Meg} = 10^6}
@math{@code{K} = 10^3}
@math{@code{mil} = 25.4^-6}
@math{@code{m} = 10^-3}
@math{@code{u} = @code{M} = 10^-6}
@math{@code{n} = 10^-9}
@math{@code{p} = 10^-12}
@math{@code{f} = 10^-15}
@end ifnottex
@tex
$$
\eqalign{\code{T} &= 10^{12} \cr
\code{G} &= 10^9 \cr
\code{Meg} &= 10^6 \cr
\code{K} &= 10^3 \cr
\code{mil} &= 25.4^{-6} \cr
\code{m} &= 10^{-3} \cr
\code{u} = \code{M} &= 10^{-6} \cr
\code{n} &= 10^{-9} \cr
\code{p} &= 10^{-12} \cr
\code{f} &= 10^{-15} \cr}
$$
@end tex
Letters immediately following a number that are not scale factors are
ignored, and letters immediately following a scale factor are ignored.
Hence, 10, 10V, 10Volts, and 10Hz all represent the same number, and
M, MA, MSec, and MMhos all represent the same scale factor. Note that
1000, 1000.0, 1000Hz, 1e3, 1.0e3, 1KHz, and 1K all represent the same
number.
Nodes names may be arbitrary character strings. The datum (ground)
node must be named '0'. Note the difference in SPICE3 where the nodes
are treated as character strings and not evaluated as numbers, thus
'0' and '00' are distinct nodes in SPICE3 but not in SPICE2. The
circuit cannot contain a loop of voltage sources and/or inductors and
cannot contain a cut-set of current sources and/or capacitors. Each
node in the circuit must have a dc path to ground. Every node must
have at least two connections except for transmission line nodes (to
permit unterminated transmission lines) and MOSFET substrate nodes
(which have two internal connections anyway).
@node Basics, Device Models, General Structure and Conventions, Circuit Description
@section Basics: Title Line, Comment Lines and .END Line
@menu
* Title Line::
* END::
* Comments::
@end menu
@node Title Line, END, Basics, Basics
@subsection Title Line
Examples:
@example
POWER AMPLIFIER CIRCUIT
TEST OF CAM CELL
@end example
The title line must be the first in the input file. Its contents are
printed verbatim as the heading for each section of output.
@node END, Comments, Title Line, Basics
@subsection .END Line
Examples:
@example
.END
@end example
The "End" line must always be the last in the input
file. Note that the period is an integral part of the
name.
@node Comments, , END, Basics
@subsection Comments
General Form:
@example
* <any comment>
@end example
Examples:
@example
* RF=1K Gain should be 100
* Check open-loop gain and phase margin
@end example
The asterisk in the first column indicates that
this line is a comment line. Comment lines may be
placed anywhere in the circuit description. Note that
SPICE3 also considers any line with leading white space
to be a comment.
@node Device Models, Subcircuits, Basics, Circuit Description
@section Device Models
General form:
@example
.MODEL MNAME TYPE(PNAME1=PVAL1 PNAME2=PVAL2 ... )
@end example
Examples:
@example
.MODEL MOD1 NPN (BF=50 IS=1E-13 VBF=50)
@end example
Most simple circuit elements typically require only a few parameter
values. However, some devices (semiconductor devices in particular)
that are included in SPICE require many parameter values. Often, many
devices in a circuit are defined by the same set of device model
parameters. For these reasons, a set of device model parameters is
defined on a separate .MODEL line and assigned a unique model name. The
device element lines in SPICE then refer to the model name.
For these more complex device types, each device element line contains
the device name, the nodes to which the device is connected, and the
device model name. In addition, other optional parameters may be
specified for some devices: geometric factors and an initial condition
(see the following section on Transistors and Diodes for more details).
MNAME in the above is the model name, and type is one of the following
fifteen types:
@vtable @code
@item R
Semiconductor resistor model
@item C
Semiconductor capacitor model
@item SW
Voltage controlled switch
@item CSW
Current controlled switch
@item URC
Uniform distributed RC model
@item LTRA
Lossy transmission line model
@item D
Diode model
@item NPN
NPN BJT model
@item PNP
PNP BJT model
@item NJF
N-channel JFET model
@item PJF
P-channel JFET model
@item NMOS
N-channel MOSFET model
@item PMOS
P-channel MOSFET model
@item NMF
N-channel MESFET model
@item PMF
P-channel MESFET model
@end vtable
Parameter values are defined by appending the parameter name followed by
an equal sign and the parameter value. Model parameters that are not
given a value are assigned the default values given below for each model
type. Models, model parameters, and default values are listed in the
next section along with the description of device element lines.
@node Subcircuits, INCLUDE, Device Models, Circuit Description
@section Subcircuits
A subcircuit that consists of SPICE elements can be defined and
referenced in a fashion similar to device models. The subcircuit is
defined in the input file by a grouping of element lines; the program
then automatically inserts the group of elements wherever the subcircuit
is referenced. There is no limit on the size or complexity of
subcircuits, and subcircuits may contain other subcircuits. An example
of subcircuit usage is given in Appendix A.
@menu
* SUBCKT::
* ENDS::
* Subcircuit Calls::
@end menu
@node SUBCKT, ENDS, Subcircuits, Subcircuits
@subsection .SUBCKT Line
General form:
@example
.SUBCKT subnam N1 <N2 N3 ...>
@end example
Examples:
@example
.SUBCKT OPAMP 1 2 3 4
@end example
A circuit definition is begun with a .SUBCKT line. SUBNAM is the
subcircuit name, and N1, N2, ... are the external nodes, which cannot
be zero. The group of element lines which immediately follow the
.SUBCKT line define the subcircuit. The last line in a subcircuit
definition is the .ENDS line (see below). Control lines may not
appear within a subcircuit definition; however, subcircuit definitions
may contain anything else, including other subcircuit definitions,
device models, and subcircuit calls (see below). Note that any device
models or subcircuit definitions included as part of a subcircuit
definition are strictly local (i.e., such models and definitions are
not known outside the subcircuit definition). Also, any element nodes
not included on the .SUBCKT line are strictly local, with the
exception of 0 (ground) which is always global.
@node ENDS, Subcircuit Calls, SUBCKT, Subcircuits
@subsection ENDS Line
General form:
@example
.ENDS <SUBNAM>
@end example
Examples:
@example
.ENDS OPAMP
@end example
The "Ends" line must be the last one for any subcircuit definition. The
subcircuit name, if included, indicates which subcircuit definition is
being terminated; if omitted, all subcircuits being defined are
terminated. The name is needed only when nested subcircuit definitions
are being made.
@node Subcircuit Calls, , ENDS, Subcircuits
@subsection Subcircuit Calls
General form:
@example
XYYYYYYY N1 <N2 N3 ...> SUBNAM
@end example
Examples:
@example
X1 2 4 17 3 1 MULTI
@end example
Subcircuits are used in SPICE by specifying pseudo-elements beginning
with the letter X, followed by the circuit nodes to be used in expanding
the subcircuit.
@node INCLUDE, , Subcircuits, Circuit Description
@section INCLUDE
General form:
@example
.INCLUDE filename
@end example
Examples:
@example
.INCLUDE /users/spice/common/wattmeter.cir
@end example
Frequently, portions of circuit descriptions will be reused in several
input files, particularly with common models and subcircuits. In any
spice input file, the ".include" line may be used to copy some other
file as if that second file appeared in place of the ".include" line
in the original file. There is no restriction on the file name
imposed by spice beyond those imposed by the local operating system.
@node Circuit Elements and Models, Analyses and Output Control, Circuit Description, Top
@chapter Circuit Elements and Models
Data fields that are enclosed in less-than and greater-than signs ('<
>') are optional. All indicated punctuation (parentheses, equal signs,
etc.) is optional but indicate the presence of any delimiter. Further,
future implementations may require the punctuation as stated. A
consistent style adhering to the punctuation shown here makes the input
easier to understand. With respect to branch voltages and currents,
SPICE uniformly uses the associated reference convention (current flows
in the direction of voltage drop).
@menu
* Elementary Devices::
* Voltage and Current Sources::
* Transmission Lines::
* Transistors and Diodes::
@end menu
@node Elementary Devices, Voltage and Current Sources, Circuit Elements and Models, Circuit Elements and Models
@section Elementary Devices
@menu
* Resistors::
* Semiconductor Resistors::
* Semiconductor Resistor Model (R)::
* Capacitors::
* Semiconductor Capacitors::
* Semiconductor Capacitor Model (C)::
* Inductors::
* Coupled (Mutual) Inductors::
* Switches::
* Switch Model (SW/CSW)::
@end menu
@node Resistors, Semiconductor Resistors, Elementary Devices, Elementary Devices
@subsection Resistors
General form:
@example
2000-06-04 13:37:29 +02:00
RXXXXXXX N1 N2 VALUE <ac=val> <m=val> <scale=val>
2000-04-27 22:03:57 +02:00
@end example
Examples:
@example
R1 1 2 100
RC1 12 17 1K
2000-05-22 07:22:51 +02:00
R2 5 7 1K ac=2K
2000-06-04 11:12:52 +02:00
RL 1 4 2K m=2
2000-04-27 22:03:57 +02:00
@end example
N1 and N2 are the two element nodes. VALUE is the resistance (in ohms)
2000-05-22 07:22:51 +02:00
and may be positive or negative but not zero. It is possible to specify
a different resistance value for ac calculations, using the "ac"
parameter. The value of ac resistance must not be zero. If you do not
2000-06-04 11:12:52 +02:00
specify the "ac" parameter, it will be defaulted to VALUE.
2000-06-04 13:37:29 +02:00
The "m" parameter is the "multiplication factor" and scale is the "scale"
factor:
Resistance = Resistance * Scale / M
2000-06-04 11:12:52 +02:00
Setting m to "val" is like putting m equal resistance in parallel.
2000-06-04 13:37:29 +02:00
The "scale" parameter let the designer to choose a different scale
for elements.
2000-04-27 22:03:57 +02:00
2000-05-22 07:22:51 +02:00
Note: ac parameter can be considered "safe" since rework-11
2000-06-04 13:37:29 +02:00
Scale parameter is not applied to l,w and other geometric
parameters.
2000-04-27 22:03:57 +02:00
@node Semiconductor Resistors, Semiconductor Resistor Model (R), Resistors, Elementary Devices
@subsection Semiconductor Resistors
General form:
@example
2000-06-04 13:37:29 +02:00
RXXXXXXX N1 N2 <VALUE> <MNAME> <L=LENGTH> <W=WIDTH> <TEMP=T> m=<val> <ac=val> <scale>
2000-04-27 22:03:57 +02:00
@end example
Examples:
@example
RLOAD 2 10 10K
RMOD 3 7 RMODEL L=10u W=1u
@end example
This is the more general form of the resistor presented in section
6.1, and allows the modeling of temperature effects and for the
calculation of the actual resistance value from strictly geometric
information and the specifications of the process. If VALUE is
specified, it overrides the geometric information and defines the
resistance. If MNAME is specified, then the resistance may be
calculated from the process information in the model MNAME and the
given LENGTH and WIDTH. If VALUE is not specified, then MNAME and
LENGTH must be specified. If WIDTH is not specified, then it is taken
from the default width given in the model. The (optional) TEMP value
is the temperature at which this device is to operate, and overrides
the temperature specification on the .OPTION control line.
@node Semiconductor Resistor Model (R), Capacitors, Semiconductor Resistors, Elementary Devices
@subsection Semiconductor Resistor Model (R)
The resistor model consists of process-related device data that allow
the resistance to be calculated from geometric information and to be
corrected for temperature. The parameters available are:
@multitable @columnfractions .15 .4 .2 .1 .1
@item name @tab parameter @tab units @tab default @tab example
@item TC1 @tab first order temperature coeff.
@tab Z/<2F> C @tab 0.0
@item TC2 @tab second order temperature coeff.
@tab Z/<2F> C@math{^2} @tab 0.0
@item RSH @tab sheet resistance
@tab Z/[] @tab - @tab 50
@item DEFW @tab default width
@tab meters @tab 1e-6 @tab 2e-6
@item NARROW @tab narrowing due to side etching
@tab meters @tab 0.0 @tab 1e-7
@item TNOM @tab parameter measurement temperature
@tab <20> C @tab 27 @tab 50
@end multitable
The sheet resistance is used with the narrowing parameter and L and W
from the resistor device to determine the nominal resistance by the
formula
@tex
$$
R = {\rm RSH} {L - {\rm NARROW} \over W - {\rm NARROW}}
$$
@end tex
@ifnottex
@example
L - NARROW
R = RSH ----------
W - NARROW
@end example
@end ifnottex
DEFW is used to supply a default value for W if one is not specified for
the device. If either RSH or L is not specified, then the standard
default resistance value of 1k Z is used. TNOM is used to override the
circuit-wide value given on the .OPTIONS control line where the
parameters of this model have been measured at a different temperature.
After the nominal resistance is calculated, it is adjusted for
temperature by the formula:
@tex
$$
R(T) = R(T_0) \Bigl( 1 + TC_1 (T - T_0) + TC_2 (T-T_0)^2 \Bigr)
$$
@end tex
@ifnottex
@example
2
R(T) = R(T ) [1 + TC (T - T ) + TC (T - T ) ]
0 1 0 2 0
@end example
@end ifnottex
@node Capacitors, Semiconductor Capacitors, Semiconductor Resistor Model (R), Elementary Devices
@subsection Capacitors
General form:
@example
CXXXXXXX N+ N- VALUE <IC=INCOND>
@end example
Examples:
@example
CBYP 13 0 1UF
COSC 17 23 10U IC=3V
@end example
N+ and N- are the positive and negative element nodes, respectively.
VALUE is the capacitance in Farads.
The (optional) initial condition is the initial (timezero) value of
capacitor voltage (in Volts). Note that the initial conditions (if any)
apply 'only' if the UIC option is specified on the .TRAN control line.
@node Semiconductor Capacitors, Semiconductor Capacitor Model (C), Capacitors, Elementary Devices
@subsection Semiconductor Capacitors
General form:
@example
CXXXXXXX N1 N2 <VALUE> <MNAME> <L=LENGTH> <W=WIDTH> <IC=VAL>
@end example
Examples:
@example
CLOAD 2 10 10P
CMOD 3 7 CMODEL L=10u W=1u
@end example
This is the more general form of the Capacitor presented in section 6.2,
and allows for the calculation of the actual capacitance value from
strictly geometric information and the specifications of the process.
If VALUE is specified, it defines the capacitance. If MNAME is
specified, then the capacitance is calculated from the process
information in the model MNAME and the given LENGTH and WIDTH. If VALUE
is not specified, then MNAME and LENGTH must be specified. If WIDTH is
not specified, then it is taken from the default width given in the
model. Either VALUE or MNAME, LENGTH, and WIDTH may be specified, but
not both sets.
@node Semiconductor Capacitor Model (C), Inductors, Semiconductor Capacitors, Elementary Devices
@subsection Semiconductor Capacitor Model (C)
The capacitor model contains process information that may be used to
compute the capacitance from strictly geometric information.
@multitable @columnfractions .15 .4 .2 .1 .1
@item name @tab parameter @tab units @tab default @tab example
@item CJ @tab junction bottom capacitance
@tab F/meters@math{^2} @tab - @tab 5e-5
@item CJSW @tab junction sidewall capacitance
@tab F/meters @tab - @tab 2e-11
@item DEFW @tab default device width
@tab meters @tab 1e-6 @tab 2e-6
@item NARROW @tab narrowing due to side etching
@tab meters @tab 0.0 @tab 1e-7
@end multitable
The capacitor has a capacitance computed as
2000-05-22 22:23:26 +02:00
@tex
$$
{\rm CAP} = {\rm CJ} ({\rm LENGTH} - {\rm NARROW})
({\rm WIDTH} - {\rm NARROW}) +
2 {\rm CJSW} ({\rm LENGTH} + {\rm WIDTH} - 2 {\rm NARROW})
$$
@end tex
@ifnottex
2000-04-27 22:03:57 +02:00
@example
2000-05-22 22:23:26 +02:00
CAP = CJ (LENGTH - NARROW) (WIDTH - NARROW) +
2 CJSW (LENGTH + WIDTH - 2 NARROW)
2000-04-27 22:03:57 +02:00
@end example
2000-05-22 22:23:26 +02:00
@end ifnottex
2000-04-27 22:03:57 +02:00
@node Inductors, Coupled (Mutual) Inductors, Semiconductor Capacitor Model (C), Elementary Devices
@subsection Inductors
General form:
@example
LYYYYYYY N+ N- VALUE <IC=INCOND>
@end example
Examples:
@example
LLINK 42 69 1UH
LSHUNT 23 51 10U IC=15.7MA
@end example
N+ and N- are the positive and negative element nodes, respectively.
VALUE is the inductance in Henries.
The (optional) initial condition is the initial (timezero) value of
inductor current (in Amps) that flows from N+, through the inductor, to
N-. Note that the initial conditions (if any) apply only if the UIC
option is specified on the .TRAN analysis line.
@node Coupled (Mutual) Inductors, Switches, Inductors, Elementary Devices
@subsection Coupled (Mutual) Inductors
General form:
@example
KXXXXXXX LYYYYYYY LZZZZZZZ VALUE
@end example
Examples:
@example
K43 LAA LBB 0.999
KXFRMR L1 L2 0.87
@end example
LYYYYYYY and LZZZZZZZ are the names of the two coupled inductors, and
VALUE is the coefficient of coupling, K, which must be greater than 0
and less than or equal to 1. Using the 'dot' convention, place a 'dot'
on the first node of each inductor.
@node Switches, Switch Model (SW/CSW), Coupled (Mutual) Inductors, Elementary Devices
@subsection Switches
General form:
@example
SXXXXXXX N+ N- NC+ NC- MODEL <ON><OFF>
WYYYYYYY N+ N- VNAM MODEL <ON><OFF>
@end example
Examples:
@example
s1 1 2 3 4 switch1 ON
s2 5 6 3 0 sm2 off
Switch1 1 2 10 0 smodel1
w1 1 2 vclock switchmod1
W2 3 0 vramp sm1 ON
wreset 5 6 vclck lossyswitch OFF
@end example
Nodes 1 and 2 are the nodes between which the switch terminals are
connected. The model name is mandatory while the initial conditions are
optional. For the voltage controlled switch, nodes 3 and 4 are the
positive and negative controlling nodes respectively. For the current
controlled switch, the controlling current is that through the specified
voltage source. The direction of positive controlling current flow is
from the positive node, through the source, to the negative node.
@node Switch Model (SW/CSW), , Switches, Elementary Devices
@subsection Switch Model (SW/CSW)
The switch model allows an almost ideal switch to be described in SPICE.
The switch is not quite ideal, in that the resistance can not change
from 0 to infinity, but must always have a finite positive value. By
proper selection of the on and off resistances, they can be effectively
zero and infinity in comparison to other circuit elements. The
parameters available are:
@multitable @columnfractions .15 .4 .2 .1 .1
@item name @tab parameter @tab units @tab default @tab switch
@item VT @tab threshold voltage @tab Volts @tab 0.0 @tab S
@item IT @tab threshold current @tab Amps @tab 0.0 @tab W
@item VH @tab hysteresis voltage @tab Volts @tab 0.0 @tab S
@item IH @tab hysteresis current @tab Amps @tab 0.0 @tab W
@item RON @tab on resistance @tab Z @tab 1.0 @tab both
@item ROFF @tab off resistance @tab Z @tab 1/GMIN* @tab both
@end multitable
*(See the .OPTIONS control line for a description of GMIN, its default
value results in an off-resistance of 1.0e+12 ohms.)
The use of an ideal element that is highly nonlinear such as a switch
can cause large discontinuities to occur in the circuit node voltages.
A rapid change such as that associated with a switch changing state can
cause numerical roundoff or tolerance problems leading to erroneous
results or timestep difficulties. The user of switches can improve the
situation by taking the following steps:
First, it is wise to set ideal switch impedances just high or low enough
to be negligible with respect to other circuit elements. Using switch
impedances that are close to "ideal" in all cases aggravates the problem
of discontinuities mentioned above. Of course, when modeling real
devices such as MOSFETS, the on resistance should be adjusted to a
realistic level depending on the size of the device being modeled.
If a wide range of ON to OFF resistance must be used in the switches
(ROFF/RON >1e+12), then the tolerance on errors allowed during transient
analysis should be decreased by using the .OPTIONS control line and
specifying TRTOL to be less than the default value of 7.0. When
switches are placed around capacitors, then the option CHGTOL should
also be reduced. Suggested values for these two options are 1.0 and
1e-16 respectively. These changes inform SPICE3 to be more careful
around the switch points so that no errors are made due to the rapid
change in the circuit.
@node Voltage and Current Sources, Transmission Lines, Elementary Devices, Circuit Elements and Models
@section Voltage and Current Sources
@menu
* Independent Sources::
* Linear Dependent Sources::
* Non-linear Dependent Sources::
@end menu
@node Independent Sources, Linear Dependent Sources, Voltage and Current Sources, Voltage and Current Sources
@subsection Independent Sources
General form:
@example
VXXXXXXX N+ N- <<DC> DC/TRAN VALUE> <AC <ACMAG <ACPHASE>>>
+ <DISTOF1 <F1MAG <F1PHASE>>> <DISTOF2 <F2MAG <F2PHASE>>>
IYYYYYYY N+ N- <<DC> DC/TRAN VALUE> <AC <ACMAG <ACPHASE>>>
+ <DISTOF1 <F1MAG <F1PHASE>>> <DISTOF2 <F2MAG <F2PHASE>>>
@end example
Examples:
@example
VCC 10 0 DC 6
VIN 13 2 0.001 AC 1 SIN(0 1 1MEG)
ISRC 23 21 AC 0.333 45.0 SFFM(0 1 10K 5 1K)
VMEAS 12 9
VCARRIER 1 0 DISTOF1 0.1 -90.0
VMODULATOR 2 0 DISTOF2 0.01
IIN1 1 5 AC 1 DISTOF1 DISTOF2 0.001
@end example
N+ and N- are the positive and negative nodes, respectively. Note that
voltage sources need not be grounded. Positive current is assumed to
flow from the positive node, through the source, to the negative node.
A current source of positive value forces current to flow out of the N+
node, through the source, and into the N- node. Voltage sources, in
addition to being used for circuit excitation, are the 'ammeters' for
SPICE, that is, zero valued voltage sources may be inserted into the
circuit for the purpose of measuring current. They of course have no
effect on circuit operation since they represent short-circuits.
DC/TRAN is the dc and transient analysis value of the source. If the
source value is zero both for dc and transient analyses, this value may
be omitted. If the source value is time-invariant (e.g., a power
supply), then the value may optionally be preceded by the letters DC.
ACMAG is the ac magnitude and ACPHASE is the ac phase. The source is
set to this value in the ac analysis. If ACMAG is omitted following the
keyword AC, a value of unity is assumed. If ACPHASE is omitted, a value
of zero is assumed. If the source is not an ac small-signal input, the
keyword AC and the ac values are omitted.
DISTOF1 and DISTOF2 are the keywords that specify that the independent
source has distortion inputs at the frequencies F1 and F2 respectively
(see the description of the .DISTO control line). The keywords may be
followed by an optional magnitude and phase. The default values of the
magnitude and phase are 1.0 and 0.0 respectively.
Any independent source can be assigned a time-dependent value for
transient analysis. If a source is assigned a time-dependent value, the
time-zero value is used for dc analysis. There are five independent
source functions: pulse, exponential, sinusoidal, piece-wise linear, and
single-frequency FM. If parameters other than source values are omitted
or set to zero, the default values shown are assumed. (TSTEP is the
printing increment and TSTOP is the final time (see the .TRAN control
line for explanation)).
@menu
* Pulse::
* Sinusoidal::
* Exponential::
* Piece-Wise Linear::
* Single-Frequency FM::
@end menu
@node Pulse, Sinusoidal, Independent Sources, Independent Sources
@subsubsection Pulse
General form:
@example
PULSE(V1 V2 TD TR TF PW PER)
@end example
Examples:
@example
VIN 3 0 PULSE(-1 1 2NS 2NS 2NS 50NS 100NS)
@end example
@multitable @columnfractions .33 .33 .33
@item parameter @tab default value @tab units
@item V1 (initial value) @tab @tab Volts or Amps
@item V2 (pulsed value) @tab @tab Volts or Amps
@item TD (delay time) @tab 0.0 @tab seconds
@item TR (rise time) @tab TSTEP @tab seconds
@item TF (fall time) @tab TSTEP @tab seconds
@item PW (pulse width) @tab TSTOP @tab seconds
@item PER(period) @tab TSTOP @tab seconds
@end multitable
A single pulse so specified is described by the following table:
@multitable @columnfractions .3 .3
@item time @tab value
@item 0 @tab V1
@item TD @tab V1
@item TD+TR @tab V2
@item TD+TR+PW @tab V2
@item TD+TR+PW+TF @tab V1
@item TSTOP @tab V1
@end multitable
Intermediate points are determined by linear interpolation.
@node Sinusoidal, Exponential, Pulse, Independent Sources
@subsubsection Sinusoidal
General form:
@example
SIN(VO VA FREQ TD THETA)
@end example
Examples:
@example
VIN 3 0 SIN(0 1 100MEG 1NS 1E10)
@end example
@multitable @columnfractions .3 .3 .3
@item parameters @tab default value @tab units
@item VO (offset) @tab @tab Volts or Amps
@item VA (amplitude) @tab @tab Volts or Amps
@item FREQ (frequency) @tab 1/TSTOP @tab Hz
@item TD (delay) @tab 0.0 @tab seconds
@item THETA (damping factor) @tab 0.0 @tab 1/seconds
@end multitable
The shape of the waveform is described by the following table:
@example
time value
------------------------------------------------------------
0 to TD VO
-(t - TD)THETA
TD to TSTOP VO + VA e sin(2 J FREQ (t + TD))
@end example
@node Exponential, Piece-Wise Linear, Sinusoidal, Independent Sources
@subsubsection Exponential
General Form:
@example
EXP(V1 V2 TD1 TAU1 TD2 TAU2)
@end example
Examples:
@example
VIN 3 0 EXP(-4 -1 2NS 30NS 60NS 40NS)
@end example
@example
parameter default value units
---------------------------------------------------------
V1 (initial value) Volts or Amps
V2 (pulsed value) Volts or Amps
TD1 (rise delay time) 0.0 seconds
TAU1 (rise time constant) TSTEP seconds
TD2 (fall delay time) TD1+TSTEP seconds
TAU2 (fall time constant) TSTEP seconds
@end example
The shape of the waveform is described by the following table:
@example
time value
----------------------------------------------------------------------------
0 to TD1 V1
| ------------|
TAU1
| -(t - TD1) | -(t - TD2)
TD1 to TD2 V1 + (V2 - V1) 1 - e
| ----------| | ----------|
| TAU1 | | TAU2 |
TD2 to TSTOP V1 + (V2 - V1) - e + (V1 - V2) 1 - e
@end example
@node Piece-Wise Linear, Single-Frequency FM, Exponential, Independent Sources
@subsubsection Piece-Wise Linear
General Form:
@example
PWL(T1 V1 <T2 V2 T3 V3 T4 V4 ...>)
@end example
Examples:
@example
VCLOCK 7 5 PWL(0 -7 10NS -7 11NS -3 17NS -3 18NS -7 50NS -7)
@end example
Each pair of values (Ti, Vi) specifies that the value of the source is
Vi (in Volts or Amps) at time=Ti. The value of the source at
intermediate values of time is determined by using linear interpolation
on the input values.
@node Single-Frequency FM, , Piece-Wise Linear, Independent Sources
@subsubsection Single-Frequency FM
General Form:
@example
SFFM(VO VA FC MDI FS)
@end example
Examples:
@example
V1 12 0 SFFM(0 1M 20K 5 1K)
@end example
@example
parameter default value units
------------------------------------------------------
VO (offset) Volts or Amps
VA (amplitude) Volts or Amps
FC (carrier frequency) 1/TSTOP Hz
MDI (modulation index)
FS (signal frequency) 1/TSTOP Hz
@end example
The shape of the waveform is described by the following equation:
@tex
$$
V(t)=V_O + V_A \sin\left| 2 J FC t + MDI \sin(2 J FS t)\right|
$$
@end tex
@ifnottex
@example
| |
V(t)=V + V sin 2 J FC t + MDI sin(2 J FS t)
O A | |
@end example
@end ifnottex
@node Linear Dependent Sources, Non-linear Dependent Sources, Independent Sources, Voltage and Current Sources
@subsection Linear Dependent Sources
SPICE allows circuits to contain linear dependent sources characterized
by any of the four equations
@tex
$$
i = g v \qquad v = e v \qquad i = f i \qquad v = h i
$$
@end tex
@ifnottex
@example
i = g v v = e v i = f i v = h i
@end example
@end ifnottex
where g, e, f, and h are constants representing transconductance,
voltage gain, current gain, and transresistance, respectively.
@menu
* Linear Voltage-Controlled Current Sources::
* Linear Voltage-Controlled Voltage Sources::
* Linear Current-Controlled Current Sources::
* Linear Current-Controlled Voltage Sources::
@end menu
@node Linear Voltage-Controlled Current Sources, Linear Voltage-Controlled Voltage Sources, Linear Dependent Sources, Linear Dependent Sources
@subsubsection Linear Voltage-Controlled Current Sources
General form:
@example
GXXXXXXX N+ N- NC+ NC- VALUE
@end example
Examples:
@example
G1 2 0 5 0 0.1MMHO
@end example
N+ and N- are the positive and negative nodes, respectively. Current
flow is from the positive node, through the source, to the negative
node. NC+ and NCare the positive and negative controlling nodes,
respectively. VALUE is the transconductance (in mhos).
@node Linear Voltage-Controlled Voltage Sources, Linear Current-Controlled Current Sources, Linear Voltage-Controlled Current Sources, Linear Dependent Sources
@subsubsection Linear Voltage-Controlled Voltage Sources
General form:
@example
EXXXXXXX N+ N- NC+ NC- VALUE
@end example
Examples:
@example
E1 2 3 14 1 2.0
@end example
N+ is the positive node, and N- is the negative node. NC+ and NC- are
the positive and negative controlling nodes, respectively. VALUE is the
voltage gain.
@node Linear Current-Controlled Current Sources, Linear Current-Controlled Voltage Sources, Linear Voltage-Controlled Voltage Sources, Linear Dependent Sources
@subsubsection Linear Current-Controlled Current Sources
General form:
@example
FXXXXXXX N+ N- VNAM VALUE
@end example
Examples:
@example
F1 13 5 VSENS 5
@end example
N+ and N- are the positive and negative nodes, respectively. Current
flow is from the positive node, through the source, to the negative
node. VNAM is the name of a voltage source through which the
controlling current flows. The direction of positive controlling
current flow is from the positive node, through the source, to the
negative node of VNAM. VALUE is the current gain.
@node Linear Current-Controlled Voltage Sources, , Linear Current-Controlled Current Sources, Linear Dependent Sources
@subsubsection Linear Current-Controlled Voltage Sources
General form:
@example
HXXXXXXX N+ N- VNAM VALUE
@end example
Examples:
@example
HX 5 17 VZ 0.5K
@end example
N+ and N- are the positive and negative nodes, respectively. VNAM is
the name of a voltage source through which the controlling current
flows. The direction of positive controlling current flow is from the
positive node, through the source, to the negative node of VNAM. VALUE
is the transresistance (in ohms).
@node Non-linear Dependent Sources, , Linear Dependent Sources, Voltage and Current Sources
@subsection Non-linear Dependent Sources
General form:
@example
BXXXXXXX N+ N- <I=EXPR> <V=EXPR>
@end example
Examples:
@example
B1 0 1 I=cos(v(1))+sin(v(2))
B1 0 1 V=ln(cos(log(v(1,2)^2)))-v(3)^4+v(2)^v(1)
B1 3 4 I=17
B1 3 4 V=exp(pi^i(vdd))
@end example
N+ is the positive node, and N- is the negative node. The values of the
V and I parameters determine the voltages and currents across and
through the device, respectively. If I is given then the device is a
current source, and if V is given the device is a voltage source. One
and only one of these parameters must be given.
The small-signal AC behavior of the nonlinear source is a linear
dependent source (or sources) with a proportionality constant equal to
the derivative (or derivatives) of the source at the DC operating point.
The expressions given for V and I may be any function of voltages and
currents through voltage sources in the system. The following functions
of real variables are defined:
@multitable @columnfractions .2 .2 .2 .2
@item abs @tab asinh @tab cosh @tab sin
@item acos @tab atan @tab exp @tab sinh
@item acosh @tab atanh @tab ln @tab sqrt
@item asin @tab cos @tab log @tab tan
@end multitable
The function "u" is the unit step function, with a value of one for
arguments greater than one and a value of zero for arguments less than
zero. The function "uramp" is the integral of the unit step: for an
input x, the value is zero if x is less than zero, or if x is greater
2000-05-23 21:53:35 +02:00
than zero the value is x. The function "u2" returns a value of zero for
arguments less than zero, one for arguments greater than one and assumes
the value of the argument between these limits .These three functions are
useful in sythesizing piece-wise non-linear functions, though convergence
may be adversely affected.
2000-04-27 22:03:57 +02:00
2000-05-23 21:53:35 +02:00
Note: "u2" function has been introduced in rework-11.
2000-04-27 22:03:57 +02:00
The following standard operators are defined:
@example
+ - * / @^{@ } unary -
@end example
If the argument of log, ln, or sqrt becomes less than zero, the absolute
value of the argument is used. If a divisor becomes zero or the
argument of log or ln becomes zero, an error will result. Other
problems may occur when the argument for a function in a partial
derivative enters a region where that function is undefined.
To get time into the expression you can integrate the current from a
constant current source with a capacitor and use the resulting voltage
(don't forget to set the initial voltage across the capacitor).
Non-linear resistors, capacitors, and inductors may be synthesized with
the nonlinear dependent source. Non-linear resistors are obvious.
Nonlinear capacitors and inductors are implemented with their linear
counterparts by a change of variables implemented with the nonlinear
dependent source. The following subcircuit will implement a nonlinear
capacitor:
@example
.Subckt nlcap pos neg
* Bx: calculate f(input voltage)
Bx 1 0 v = f(v(pos,neg))
* Cx: linear capacitance
Cx 2 0 1
* Vx: Ammeter to measure current into the capacitor
Vx 2 1 DC 0Volts
* Drive the current through Cx back into the circuit
Fx pos neg Vx 1
.ends
@end example
Non-linear inductors are similar.
@node Transmission Lines, Transistors and Diodes, Voltage and Current Sources, Circuit Elements and Models
@section Transmission Lines
@menu
* Lossless Transmission Lines::
* Lossy Transmission Lines::
* Lossy Transmission Line Model (LTRA)::
* Uniform Distributed RC Lines (Lossy)::
* Uniform Distributed RC Model (URC)::
@end menu
@node Lossless Transmission Lines, Lossy Transmission Lines, Transmission Lines, Transmission Lines
@subsection Lossless Transmission Lines
General form:
@example
TXXXXXXX N1 N2 N3 N4 Z0=VALUE <TD=VALUE> <F=FREQ <NL=NRMLEN>>
+ <IC=V1, I1, V2, I2>
@end example
Examples:
@example
T1 1 0 2 0 Z0=50 TD=10NS
@end example
N1 and N2 are the nodes at port 1; N3 and N4 are the nodes at port 2.
Z0 is the characteristic impedance. The length of the line may be
expressed in either of two forms. The transmission delay, TD, may be
specified directly (as TD=10ns, for example). Alternatively, a
frequency F may be given, together with NL, the normalized electrical
length of the transmission line with respect to the wavelength in the
line at the frequency F. If a frequency is specified but NL is omitted,
0.25 is assumed (that is, the frequency is assumed to be the
quarter-wave frequency). Note that although both forms for expressing
the line length are indicated as optional, one of the two must be
specified.
Note that this element models only one propagating mode. If all four
nodes are distinct in the actual circuit, then two modes may be excited.
To simulate such a situation, two transmission-line elements are
required. (see the example in Appendix A for further clarification.)
The (optional) initial condition specification consists of the voltage
and current at each of the transmission line ports. Note that the
initial conditions (if any) apply 'only' if the UIC option is specified
on the .TRAN control line.
Note that a lossy transmission line (see below) with zero loss may be
more accurate than than the lossless transmission line due to
implementation details.
@node Lossy Transmission Lines, Lossy Transmission Line Model (LTRA), Lossless Transmission Lines, Transmission Lines
@subsection Lossy Transmission Lines
General form:
@example
OXXXXXXX N1 N2 N3 N4 MNAME
@end example
Examples:
@example
O23 1 0 2 0 LOSSYMOD
OCONNECT 10 5 20 5 INTERCONNECT
@end example
This is a two-port convolution model for singleconductor lossy
transmission lines. N1 and N2 are the nodes at port 1; N3 and N4 are
the nodes at port 2. Note that a lossy transmission line with zero loss
may be more accurate than than the lossless transmission line due to
implementation details.
@node Lossy Transmission Line Model (LTRA), Uniform Distributed RC Lines (Lossy), Lossy Transmission Lines, Transmission Lines
@subsection Lossy Transmission Line Model (LTRA)
The uniform RLC/RC/LC/RG transmission line model (referred to as the
LTRA model henceforth) models a uniform constant-parameter distributed
transmission line. The RC and LC cases may also be modeled using the
URC and TRA models; however, the newer LTRA model is usually faster and
more accurate than the others. The operation of the LTRA model is based
on the convolution of the transmission line's impulse responses with its
inputs (see [8]).
The LTRA model takes a number of parameters, some of which must be given
and some of which are optional.
@multitable @columnfractions .15 .4 .2 .1 .1
@item name @tab parameter @tab units/type @tab default @tab example
@item name @tab parameter @tab units/type @tab default @tab example
@item R @tab resistance/length @tab Z/unit @tab 0.0 @tab 0.2
@item L @tab inductance/length @tab henrys/unit @tab 0.0 @tab 9.13e-9
@item G @tab conductance/length @tab mhos/unit @tab 0.0 @tab 0.0
@item C @tab capacitance/length @tab farads/unit @tab 0.0 @tab 3.65e-12
@item LEN @tab length of line @tab no default @tab 1.0
@item REL @tab breakpoint control @tab arbitrary unit @tab 1 @tab 0.5
@item ABS @tab breakpoint control @tab 1 @tab 5
@item NOSTEPLIMIT @tab don't limit timestep to less than line delay
@tab flag @tab not set @tab set
@item NOCONTROL @tab don't do complex timestep control
@tab flag @tab not set @tab set
@item LININTERP @tab use linear interpolation
@tab flag @tab not set @tab set
@item MIXEDINTERP @tab use linear when quadratic seems bad
@tab not set @tab set
@item COMPACTREL @tab special reltol for history compaction
@tab flag @tab RELTOL @tab 1.0e-3
@item COMPACTABS @tab special abstol for history compaction
@tab ABSTOL @tab 1.0e-9
@item TRUNCNR @tab use Newton-Raphson method for timestep control
@tab flag @tab not set @tab set
@item TRUNCDONTCUT @tab don't limit timestep to keep impulse-response
errors low @tab flag @tab not set @tab set
@end multitable
The following types of lines have been implemented so far: RLC (uniform
transmission line with series loss only), RC (uniform RC line), LC
(lossless transmission line), and RG (distributed series resistance and
parallel conductance only). Any other combination will yield erroneous
results and should not be tried. The length LEN of the line must be
specified.
NOSTEPLIMIT is a flag that will remove the default restriction of
limiting time-steps to less than the line delay in the RLC case.
NOCONTROL is a flag that prevents the default limiting of the time-step
based on convolution error criteria in the RLC and RC cases. This
speeds up simulation but may in some cases reduce the accuracy of
results. LININTERP is a flag that, when specified, will use linear
interpolation instead of the default quadratic interpolation for
calculating delayed signals. MIXEDINTERP is a flag that, when
specified, uses a metric for judging whether quadratic interpolation is
not applicable and if so uses linear interpolation; otherwise it uses
the default quadratic interpolation. TRUNCDONTCUT is a flag that
removes the default cutting of the time-step to limit errors in the
actual calculation of impulse-response related quantities. COMPACTREL
and COMPACTABS are quantities that control the compaction of the past
history of values stored for convolution. Larger values of these lower
accuracy but usually increase simulation speed. These are to be used
with the TRYTOCOMPACT option, described in the .OPTIONS section.
TRUNCNR is a flag that turns on the use of Newton-Raphson iterations to
determine an appropriate timestep in the timestep control routines. The
default is a trial and error procedure by cutting the previous timestep
in half. REL and ABS are quantities that control the setting of
breakpoints.
The option most worth experimenting with for increasing the speed of
simulation is REL. The default value of 1 is usually safe from the
point of view of accuracy but occasionally increases computation time.
A value greater than 2 eliminates all breakpoints and may be worth
trying depending on the nature of the rest of the circuit, keeping in
mind that it might not be safe from the viewpoint of accuracy.
Breakpoints may usually be entirely eliminated if it is expected the
circuit will not display sharp discontinuities. Values between 0 and 1
are usually not required but may be used for setting many breakpoints.
COMPACTREL may also be experimented with when the option TRYTOCOMPACT is
specified in a .OPTIONS card. The legal range is between 0 and 1.
Larger values usually decrease the accuracy of the simulation but in
some cases improve speed. If TRYTOCOMPACT is not specified on a
.OPTIONS card, history compaction is not attempted and accuracy is high.
NOCONTROL, TRUNCDONTCUT and NOSTEPLIMIT also tend to increase speed at
the expense of accuracy.
@node Uniform Distributed RC Lines (Lossy), Uniform Distributed RC Model (URC), Lossy Transmission Line Model (LTRA), Transmission Lines
@subsection Uniform Distributed RC Lines (Lossy)
General form:
@example
UXXXXXXX N1 N2 N3 MNAME L=LEN <N=LUMPS>
@end example
Examples:
@example
U1 1 2 0 URCMOD L=50U
URC2 1 12 2 UMODL l=1MIL N=6
@end example
N1 and N2 are the two element nodes the RC line connects, while N3 is
the node to which the capacitances are connected. MNAME is the model
name, LEN is the length of the RC line in meters. LUMPS, if specified,
is the number of lumped segments to use in modeling the RC line (see the
model description for the action taken if this parameter is omitted).
@node Uniform Distributed RC Model (URC), , Uniform Distributed RC Lines (Lossy), Transmission Lines
@subsection Uniform Distributed RC Model (URC)
The URC model is derived from a model proposed by L. Gertzberrg in
1974. The model is accomplished by a subcircuit type expansion of the
URC line into a network of lumped RC segments with internally generated
nodes. The RC segments are in a geometric progression, increasing
toward the middle of the URC line, with @math{K} as a proportionality
constant. The number of lumped segments used, if not specified for the
URC line device, is determined by the following formula:
@tex
$$
N = { \log \left|
F_{\rm max} {R\over L}{C \over L} 2 J L^2
\left| (K - 1) \over K \right|^2
\right| \over \log K }
$$
@end tex
@ifnottex
@example
2
| R C |(K-1)| |
_ _ 2
log|F 2 J L |-----| |
max
| L L | K | |
N = ------------------------------
log K
@end example
@end ifnottex
The URC line is made up strictly of resistor and capacitor segments
unless the ISPERL parameter is given a nonzero value, in which case the
capacitors are replaced with reverse biased diodes with a zero-bias
junction capacitance equivalent to the capacitance replaced, and with a
saturation current of ISPERL amps per meter of transmission line and an
optional series resistance equivalent to RSPERL ohms per meter.
2000-05-22 22:23:26 +02:00
@multitable @columnfractions .1 .45 .1 .15 .1 .1
@item name @tab parameter
@tab units @tab default @tab example
@item K @tab Propagation Constant
@tab - @tab 2.0 @tab 1.2
@item FMAX @tab Maximum Frequency of interest
@tab Hz @tab 1.0G @tab 6.5Meg
@item RPERL @tab Resistance per unit length
@tab Z/m @tab 1000 @tab 10
@item CPERL @tab Capacitance per unit length
@tab F/m @tab 1.0e-15 @tab 1pF
@item ISPERL @tab Saturation Current per unit length
@tab A/m @tab 0 @tab -
@item RSPERL @tab Diode Resistance per unit length
@tab Z/m @tab 0 @tab -
2000-04-27 22:03:57 +02:00
@end multitable
@node Transistors and Diodes, , Transmission Lines, Circuit Elements and Models
@section Transistors and Diodes
The area factor used on the diode, BJT, JFET, and MESFET devices
determines the number of equivalent parallel devices of a specified
model. The affected parameters are marked with an asterisk under the
heading 'area' in the model descriptions below. Several geometric
factors associated with the channel and the drain and source diffusions
can be specified on the MOSFET device line.
Two different forms of initial conditions may be specified for some
devices. The first form is included to improve the dc convergence for
circuits that contain more than one stable state. If a device is
specified OFF, the dc operating point is determined with the terminal
voltages for that device set to zero. After convergence is obtained,
the program continues to iterate to obtain the exact value for the
terminal voltages. If a circuit has more than one dc stable state, the
OFF option can be used to force the solution to correspond to a desired
state. If a device is specified OFF when in reality the device is
conducting, the program still obtains the correct solution (assuming the
solutions converge) but more iterations are required since the program
must independently converge to two separate solutions. The .NODESET
control line serves a similar purpose as the OFF option. The .NODESET
option is easier to apply and is the preferred means to aid convergence.
The second form of initial conditions are specified for use with the
transient analysis. These are true 'initial conditions' as opposed to
the convergence aids above. See the description of the .IC control line
and the .TRAN control line for a detailed explanation of initial
conditions.
@menu
* Junction Diodes::
* Diode Model (D)::
* Bipolar Junction Transistors (BJTs)::
* BJT Models (NPN/PNP)::
* Junction Field-Effect Transistors (JFETs)::
* JFET Models (NJF/PJF)::
* MOSFETs::
* MOSFET Models (NMOS/PMOS)::
* MESFETs::
* MESFET Models (NMF/PMF)::
@end menu
@node Junction Diodes, Diode Model (D), Transistors and Diodes, Transistors and Diodes
@subsection Junction Diodes
General form:
@example
DXXXXXXX N+ N- MNAME <AREA> <OFF> <IC=VD> <TEMP=T>
@end example
Examples:
@example
DBRIDGE 2 10 DIODE1
DCLMP 3 7 DMOD 3.0 IC=0.2
@end example
N+ and N- are the positive and negative nodes, respectively. MNAME is
the model name, AREA is the area factor, and OFF indicates an (optional)
starting condition on the device for dc analysis. If the area factor is
omitted, a value of 1.0 is assumed. The (optional) initial condition
specification using IC=VD is intended for use with the UIC option on the
.TRAN control line, when a transient analysis is desired starting from
other than the quiescent operating point. The (optional) TEMP value is
the temperature at which this device is to operate, and overrides the
temperature specification on the .OPTION control line.
@node Diode Model (D), Bipolar Junction Transistors (BJTs), Junction Diodes, Transistors and Diodes
@subsection Diode Model (D)
The dc characteristics of the diode are determined by the parameters IS
and N. An ohmic resistance, RS, is included. Charge storage effects
are modeled by a transit time, TT, and a nonlinear depletion layer
capacitance which is determined by the parameters CJO, VJ, and M. The
temperature dependence of the saturation current is defined by the
parameters EG, the energy and XTI, the saturation current temperature
exponent. The nominal temperature at which these parameters were
measured is TNOM, which defaults to the circuit-wide value specified on
the .OPTIONS control line. Reverse breakdown is modeled by an
exponential increase in the reverse diode current and is determined by
the parameters BV and IBV (both of which are positive numbers).
2000-05-22 22:26:26 +02:00
@multitable @columnfractions .1 .45 .15 .15 .15 .1
2000-04-27 22:03:57 +02:00
@item name @tab parameter @tab units @tab default @tab example @tab area
@item IS @tab saturation current @tab A @tab 1.0e-14 @tab 1.0e-14 @tab *
@item RS @tab ohmic resistance @tab Z @tab 0 @tab 10 @tab *
@item N @tab emission coefficient @tab - @tab 1 @tab 1.0
@item TT @tab transit-time @tab sec @tab 0 @tab 0.1ns
@item CJO @tab zero-bias junction capacitance
@tab F @tab 0 @tab 2pF @tab *
@item VJ @tab junction potential @tab V @tab 1 @tab 0.6
@item M @tab grading coefficient @tab - @tab 0.5 @tab 0.5
@item EG @tab activation energy
@tab eV @tab 1.11 @tab 1.11 Si; 0.69 Sbd; 0.67 Ge
@item XTI @tab saturation-current temp. exp
@tab - @tab 3.0 @tab 3.0 jn; 2.0 Sbd
@item KF @tab flicker noise coefficient @tab - @tab 0
@item AF @tab flicker noise exponent @tab - @tab 1
@item FC @tab coefficient for forward-bias
@tab - @tab 0.5 @tab depletion capacitance formula
@item BV @tab reverse breakdown voltage @tab V @tab infinite @tab 40.0
@item IBV @tab current at breakdown voltage @tab A @tab 1.0e-3
@item TNOM @tab parameter measurement temperature @tab C @tab 27 @tab 50
@end multitable
@node Bipolar Junction Transistors (BJTs), BJT Models (NPN/PNP), Diode Model (D), Transistors and Diodes
@subsection Bipolar Junction Transistors (BJTs)
General form:
@example
QXXXXXXX NC NB NE <NS> MNAME <AREA> <OFF> <IC=VBE, VCE> <TEMP=T>
@end example
Examples:
@example
Q23 10 24 13 QMOD IC=0.6, 5.0
Q50A 11 26 4 20 MOD1
@end example
NC, NB, and NE are the collector, base, and emitter nodes, respectively.
NS is the (optional) substrate node. If unspecified, ground is used.
MNAME is the model name, AREA is the area factor, and OFF indicates an
(optional) initial condition on the device for the dc analysis. If the
area factor is omitted, a value of 1.0 is assumed. The (optional)
initial condition specification using IC=VBE, VCE is intended for use
with the UIC option on the .TRAN control line, when a transient analysis
is desired starting from other than the quiescent operating point. See
the .IC control line description for a better way to set transient
initial conditions. The (optional) TEMP value is the temperature at
which this device is to operate, and overrides the temperature
specification on the .OPTION control line.
@node BJT Models (NPN/PNP), Junction Field-Effect Transistors (JFETs), Bipolar Junction Transistors (BJTs), Transistors and Diodes
@subsection BJT Models (NPN/PNP)
The bipolar junction transistor model in SPICE is an adaptation of the
integral charge control model of Gummel and Poon. This modified
Gummel-Poon model extends the original model to include several effects
at high bias levels. The model automatically simplifies to the simpler
Ebers-Moll model when certain parameters are not specified. The
parameter names used in the modified Gummel-Poon model have been chosen
to be more easily understood by the program user, and to reflect better
both physical and circuit design thinking.
The dc model is defined by the parameters IS, BF, NF, ISE, IKF, and NE
which determine the forward current gain characteristics, IS, BR, NR,
ISC, IKR, and NC which determine the reverse current gain
characteristics, and VAF and VAR which determine the output conductance
for forward and reverse regions. Three ohmic resistances RB, RC, and RE
are included, where RB can be high current dependent. Base charge
storage is modeled by forward and reverse transit times, TF and TR, the
forward transit time TF being bias dependent if desired, and nonlinear
depletion layer capacitances which are determined by CJE, VJE, and MJE
for the B-E junction , CJC, VJC, and MJC for the B-C junction and CJS,
VJS, and MJS for the C-S (Collector-Substrate) junction. The
temperature dependence of the saturation current, IS, is determined by
the energy-gap, EG, and the saturation current temperature exponent,
XTI. Additionally base current temperature dependence is modeled by the
beta temperature exponent XTB in the new model. The values specified
are assumed to have been measured at the temperature TNOM, which can be
specified on the .OPTIONS control line or overridden by a specification
on the .MODEL line.
The BJT parameters used in the modified Gummel-Poon model are listed
below. The parameter names used in earlier versions of SPICE2 are still
accepted.
Modified Gummel-Poon BJT Parameters.
2000-05-22 22:26:26 +02:00
@multitable @columnfractions .1 .45 .15 .15 .15 .1
2000-04-27 22:03:57 +02:00
@item name @tab parameter @tab units @tab default @tab example @tab area
@item IS @tab transport saturation current @tab A @tab 1.0e-16 @tab
1.0e-15 @tab *
@item BF @tab ideal maximum forward beta @tab - @tab 100 @tab 100
@item NF @tab forward current emission coefficient @tab - @tab 1.0 @tab 1
@item VAF @tab forward Early voltage @tab V @tab infinite @tab 200
@item IKF @tab corner for forward beta current roll-off @tab A @tab
infinite @tab 0.01 @tab *
@item ISE @tab B-E leakage saturation current @tab A @tab 0 @tab 1.0e-13
@tab *
@item NE @tab B-E leakage emission coefficient @tab - @tab 1.5 @tab 2
@item BR @tab ideal maximum reverse beta @tab - @tab 1 @tab 0.1
@item NR @tab reverse current emission coefficient @tab - @tab 1
@tab 1
@item VAR @tab reverse Early voltage @tab V @tab infinite @tab 200
@item IKR @tab corner for reverse beta high current roll-off
@tab A @tab infinite @tab 0.01 @tab *
@item ISC @tab B-C leakage saturation current @tab A @tab 0 @tab 1.0e-13
@tab *
@item NC @tab B-C leakage emission coefficient @tab - @tab 2 @tab 1.5
@item RB @tab zero bias base resistance @tab Z @tab 0 @tab 100 @tab *
@item IRB @tab current where base resistance falls halfway to its min
value @tab A @tab infinite @tab 0.1 @tab *
@item RBM @tab minimum base resistance at high currents @tab Z @tab RB
10 @tab *
@item RE @tab emitter resistance @tab Z @tab 0 @tab 1 @tab *
@item RC @tab collector resistance @tab Z @tab 0 @tab 10 @tab *
@item CJE @tab B-E zero-bias depletion capacitance @tab F @tab 0 @tab
2pF @tab *
@item VJE @tab B-E built-in potential @tab V @tab 0.75 @tab 0.6
@item MJE @tab B-E junction exponential factor @tab - @tab 0.33 @tab 0.33
@item TF @tab ideal forward transit time @tab sec @tab 0 @tab 0.1ns
@item XTF @tab coefficient for bias dependence of TF @tab - @tab 0
@item VTF @tab voltage describing VBC dependence of TF @tab V @tab infinite
@item ITF @tab high-current parameter for effect on TF @tab A @tab 0
@tab *
@item PTF @tab excess phase at freq=1.0/(TF*2PI) Hz @tab deg @tab 0
@item CJC @tab B-C zero-bias depletion capacitance @tab F @tab 0 @tab
2pF @tab *
@item VJC @tab B-C built-in potential @tab V @tab 0.75 @tab 0.5
@item MJC @tab B-C junction exponential factor @tab - @tab 0.33 @tab 0.5
@item XCJC @tab fraction of B-C depletion capacitance connected to
internal base node @tab - @tab 1
@item TR @tab ideal reverse transit time @tab sec @tab 0 @tab 10ns
@item CJS @tab zero-bias collector-substrate capacitance @tab F @tab 0
@tab 2pF @tab *
@item VJS @tab substrate junction built-in potential @tab V @tab 0.75
@item MJS @tab substrate junction exponential factor @tab - @tab 0 @tab 0.5
@item XTB @tab forward and reverse beta temperature exponent @tab - @tab
0
@item EG @tab energy gap for temperature effect on IS @tab eV @tab 1.11
@item XTI @tab temperature exponent for effect on IS @tab - @tab 3
@item KF @tab flicker-noise coefficient @tab - @tab 0
@item AF @tab flicker-noise exponent @tab - @tab 1
@item FC @tab coefficient for forward-bias depletion capacitance formula
@tab - @tab 0.5 @tab o
2000-05-22 22:23:26 +02:00
@item TNOM @tab Parameter measurement temperature @tab <20> C @tab 27 @tab 50
2000-04-27 22:03:57 +02:00
@end multitable
@node Junction Field-Effect Transistors (JFETs), JFET Models (NJF/PJF), BJT Models (NPN/PNP), Transistors and Diodes
@subsection Junction Field-Effect Transistors (JFETs)
General form:
@example
JXXXXXXX ND NG NS MNAME <AREA> <OFF> <IC=VDS, VGS> <TEMP=T>
@end example
Examples:
@example
J1 7 2 3 JM1 OFF
@end example
ND, NG, and NS are the drain, gate, and source nodes, respectively.
MNAME is the model name, AREA is the area factor, and OFF indicates an
(optional) initial condition on the device for dc analysis. If the area
factor is omitted, a value of 1.0 is assumed. The (optional) initial
condition specification, using IC=VDS, VGS is intended for use with the
UIC option on the .TRAN control line, when a transient analysis is
desired starting from other than the quiescent operating point. See the
.IC control line for a better way to set initial conditions. The
(optional) TEMP value is the temperature at which this device is to
operate, and overrides the temperature specification on the .OPTION
control line.
@node JFET Models (NJF/PJF), MOSFETs, Junction Field-Effect Transistors (JFETs), Transistors and Diodes
@subsection JFET Models (NJF/PJF)
The JFET model is derived from the FET model of Shichman and Hodges.
The dc characteristics are defined by the parameters VTO and BETA, which
determine the variation of drain current with gate voltage, LAMBDA,
which determines the output conductance, and IS, the saturation current
of the two gate junctions. Two ohmic resistances, RD and RS, are
included. Charge storage is modeled by nonlinear depletion layer
capacitances for both gate junctions which vary as the -1/2 power of
junction voltage and are defined by the parameters CGS, CGD, and PB.
Note that in Spice3f and later, a fitting parameter B has been added.
For details, see [9].
2000-05-22 22:26:26 +02:00
@multitable @columnfractions .1 .45 .15 .15 .15 .1
2000-04-27 22:03:57 +02:00
@item name @tab parameter @tab units @tab default @tab example @tab area
@item VTO @tab threshold voltage (@math{V_T0}) @tab V @tab -2.0 @tab -2.0
@item BETA @tab transconductance parameter (B)
@tab A/V@math{^2} @tab 1.0e-4 @tab 1.0e-3 @tab *
@item LAMBDA @tab channel-length modulation parameter (L)
@tab 1/V @tab 0 @tab 1.0e-4
@item RD @tab drain ohmic resistance @tab Z @tab 0 @tab 100 @tab *
@item RS @tab source ohmic resistance @tab Z @tab 0 @tab 100 @tab *
@item CGS @tab zero-bias G-S junction capacitance (@math{C_gs})
@tab F @tab 0 @tab 5pF @tab *
@item CGD @tab zero-bias G-D junction capacitance (@math{C_gs})
@tab F @tab 0 @tab 1pF @tab *
@item PB @tab gate junction potential @tab V @tab 1 @tab 0.6
@item IS @tab gate junction saturation current (@math{I_S})
@tab A @tab 1.0e-14 @tab 1.0e-14 @tab *
@item B @tab doping tail parameter @tab - @tab 1 @tab 1.1
@item KF @tab flicker noise coefficient @tab - @tab 0
@item AF @tab flicker noise exponent @tab - @tab 1
@item FC @tab coefficient for forward-bias depletion capacitance formula
@tab - @tab 0.5
@item TNOM @tab parameter measurement temperature
@tab <20> C @tab 27 @tab 50
@end multitable
@node MOSFETs, MOSFET Models (NMOS/PMOS), JFET Models (NJF/PJF), Transistors and Diodes
@subsection MOSFETs
General form:
@example
MXXXXXXX ND NG NS NB MNAME <L=VAL> <W=VAL> <AD=VAL> <AS=VAL>
+ <PD=VAL> <PS=VAL> <NRD=VAL> <NRS=VAL> <OFF>
+ <IC=VDS, VGS, VBS> <TEMP=T>
@end example
Examples:
@example
M1 24 2 0 20 TYPE1
M31 2 17 6 10 MODM L=5U W=2U
M1 2 9 3 0 MOD1 L=10U W=5U AD=100P AS=100P PD=40U PS=40U
@end example
ND, NG, NS, and NB are the drain, gate, source, and bulk (substrate)
nodes, respectively. MNAME is the model name. L and W are the channel
length and width, in meters. AD and AS are the areas of the drain and
source diffusions, in meters@math{^2}. Note that the suffix U specifies
microns (1e-6 m) and P sq-microns (1e-12 m@math{^2}). If any of L, W,
AD, or AS are not specified, default values are used. The use of
defaults simplifies input file preparation, as well as the editing
required if device geometries are to be changed. PD and PS are the
perimeters of the drain and source junctions, in meters. NRD and NRS
designate the equivalent number of squares of the drain and source
diffusions; these values multiply the sheet resistance RSH specified on
the .MODEL control line for an accurate representation of the parasitic
series drain and source resistance of each transistor. PD and PS
default to 0.0 while NRD and NRS to 1.0. OFF indicates an (optional)
initial condition on the device for dc analysis. The (optional) initial
condition specification using IC=VDS, VGS, VBS is intended for use with
the UIC option on the .TRAN control line, when a transient analysis is
desired starting from other than the quiescent operating point. See the
.IC control line for a better and more convenient way to specify
transient initial conditions. The (optional) TEMP value is the
temperature at which this device is to operate, and overrides the
temperature specification on the .OPTION control line. The temperature
specification is ONLY valid for level 1, 2, 3, and 6 MOSFETs, not for
level 4 or 5 (BSIM) devices.
@node MOSFET Models (NMOS/PMOS), MESFETs, MOSFETs, Transistors and Diodes
@subsection MOSFET Models (NMOS/PMOS)
SPICE provides four MOSFET device models, which differ in the
formulation of the I-V characteristic. The variable LEVEL specifies the
model to be used:
@table @code
@item LEVEL=1
Shichman-Hodges
@item LEVEL=2
MOS2 (as described in [1])
@item LEVEL=3
MOS3, a semi-empirical model(see [1])
@item LEVEL=4
BSIM (as described in [3])
@item LEVEL=5
new BSIM (BSIM2; as described in [5])
@item LEVEL=6
MOS6 (as described in [2])
@end table
The dc characteristics of the level 1 through level 3 MOSFETs are
defined by the device parameters VTO, KP, LAMBDA, PHI and GAMMA. These
parameters are computed by SPICE if process parameters (NSUB, TOX, ...)
are given, but userspecified values always override. VTO is positive
(negative) for enhancement mode and negative (positive) for depletion
mode N-channel (P-channel) devices. Charge storage is modeled by three
constant capacitors, CGSO, CGDO, and CGBO which represent overlap
capacitances, by the nonlinear thin-oxide capacitance which is
distributed among the gate, source, drain, and bulk regions, and by the
nonlinear depletion-layer capacitances for both substrate junctions
divided into bottom and periphery, which vary as the MJ and MJSW power
of junction voltage respectively, and are determined by the parameters
CBD, CBS, CJ, CJSW, MJ, MJSW and PB. Charge storage effects are modeled
by the piecewise linear voltages-dependent capacitance model proposed by
Meyer. The thin-oxide charge-storage effects are treated slightly
different for the LEVEL=1 model. These voltage-dependent capacitances
are included only if TOX is specified in the input description and they
are represented using Meyer's formulation.
There is some overlap among the parameters describing the junctions,
e.g. the reverse current can be input either as IS (in A) or as JS (in
A/m@math{^2}). Whereas the first is an absolute value the second is
multiplied by AD and AS to give the reverse current of the drain and
source junctions respectively. This methodology has been chosen since
there is no sense in relating always junction characteristics with AD
and AS entered on the device line; the areas can be defaulted. The same
idea applies also to the zero-bias junction capacitances CBD and CBS (in
F) on one hand, and CJ (in F/m@math{^2}) on the other. The parasitic
drain and source series resistance can be expressed as either RD and RS
(in ohms) or RSH (in ohms/sq.), the latter being multiplied by the
number of squares NRD and NRS input on the device line.
A discontinuity in the MOS level 3 model with respect to the KAPPA
parameter has been detected (see [10]). The supplied fix has been
implemented in Spice3f2 and later. Since this fix may affect parameter
fitting, the option "BADMOS3" may be set to use the old implementation
(see the section on simulation variables and the ".OPTIONS" line).
SPICE level 1, 2, 3 and 6 parameters:
2000-05-22 22:23:26 +02:00
@multitable @columnfractions .1 .45 .15 .15 .15
@item name @tab parameter
@tab units @tab default @tab example
@item LEVEL @tab model index
@tab - @tab 1
@item VTO @tab zero-bias threshold voltage (@math{V_T0})
@tab V @tab 0.0 @tab 1.0
@item KP @tab transconductance parameter
@tab @math{A/V^2} @tab 2.0e-5 @tab 3.1e-5
@item GAMMA @tab bulk threshold parameter
@tab @math{V^1/2} @tab 0.0 @tab 0.37
@item PHI @tab surface potential (U)
@tab V @tab 0.6 @tab 0.65
@item LAMBDA @tab channel-length modulation (MOS1 and MOS2 only) (L)
@tab 1/V @tab 0.0 @tab 0.02
@item RD @tab drain ohmic resistance
@tab Z @tab 0.0 @tab 1.0
@item RS @tab source ohmic resistance
@tab Z @tab 0.0 @tab 1.0
@item CBD @tab zero-bias B-D junction capacitance
@tab F @tab 0.0 @tab 20fF
@item CBS @tab zero-bias B-S junction capacitance
@tab F @tab 0.0 @tab 20fF
@item IS @tab bulk junction saturation current (@math{I_S})
@tab A @tab 1.0e-14 @tab 1.0e-15
@item PB @tab bulk junction potential
@tab V @tab 0.8 @tab 0.87
@item CGSO @tab gate-source overlap capacitance per meter channel width
@tab F/m @tab 0.0 @tab 4.0e-11
@item CGDO @tab gate-drain overlap capacitance per meter channel width
@tab F/m @tab 0.0 @tab 4.0e-11
@item CGBO @tab gate-bulk overlap capacitance per meter channel length
@tab F/m @tab 0.0 @tab 2.0e-10
@item RSH @tab drain and source diffusion sheet resistance
@tab Z/[] @tab 0.0 @tab 10.0
@item CJ @tab zero-bias bulk junction bottom cap. per sq-meter of junction area
@tab @math{F/m^2} @tab 0.0 @tab 2.0e-4
@item MJ @tab bulk junction bottom grading coeff.
@tab - @tab 0.5 @tab 0.5
@item CJSW @tab zero-bias bulk junction sidewall cap. per meter of junction perimeter
@tab F/m @tab 0.0 @tab 1.0e-9
@item MJSW @tab bulk junction sidewall grading coeff.
@tab - @tab 0.50(level1), 0.33(level2, 3)
@item JS @tab bulk junction saturation current per sq-meter of junction area
@tab @math{A/m^2} @tab 1.0e-8
@item TOX @tab oxide thickness
@tab meter @tab 1.0e-7 @tab 1.0e-7
@item NSUB @tab substrate doping
@tab @math{1/cm^3} @tab 0.0 @tab 4.0e15
@item NSS @tab surface state density
@tab @math{1/cm^2} @tab 0.0 @tab 1.0e10
@item NFS @tab fast surface state density
@tab @math{1/cm^2} @tab 0.0 @tab 1.0e10
@item TPG @tab type of gate material:
+1 opp. to substrate, -1 same as substrate, 0 Al gate
@tab - @tab 1.0
@item XJ @tab metallurgical junction depth
@tab meter @tab 0.0 @tab 1M
@item LD @tab lateral diffusion
@tab meter @tab 0.0 @tab 0.8M
@item UO @tab surface mobility
@tab @math{cm^2/Vs} @tab 600 @tab 700
@item UCRIT @tab critical field for mobility degradation (MOS2 only)
@tab V/cm @tab 1.0e4 @tab 1.0e4
@item UEXP @tab critical field exponent in mobility degradation (MOS2 only)
@tab - @tab 0.0 @tab 0.1
@item UTRA @tab transverse field coeff. (mobility) (deleted for MOS2)
@tab - @tab 0.0 @tab 0.3
@item VMAX @tab maximum drift velocity of carriers
@tab m/s @tab 0.0 @tab 5.0e4
@item NEFF @tab total channel-charge (fixed and mobile) coefficient (MOS2 only)
@tab - @tab 1.0 @tab 5.0
@item KF @tab flicker noise coefficient
@tab - @tab 0.0 @tab 1.0e-26
@item AF @tab flicker noise exponent
@tab - @tab 1.0 @tab 1.2
@item FC @tab coefficient for forward-bias depletion capacitance formula
@tab - @tab 0.5
@item DELTA @tab width effect on threshold voltage (MOS2 and MOS3)
@tab - @tab 0.0 @tab 1.0
@item THETA @tab mobility modulation (MOS3 only)
@tab 1/V @tab 0.0 @tab 0.1
@item ETA @tab static feedback (MOS3 only)
@tab - @tab 0.0 @tab 1.0
@item KAPPA @tab saturation field factor (MOS3 only)
@tab - @tab 0.2 @tab 0.5
@item TNOM @tab parameter measurement temperature
@tab <20> C @tab 27 @tab 50
@end multitable
2000-04-27 22:03:57 +02:00
The level 4 and level 5 (BSIM1 and BSIM2) parameters are all values
obtained from process characterization, and can be generated
automatically. J. Pierret [4] describes a means of generating a
'process' file, and the program Proc2Mod provided with SPICE3 converts
this file into a sequence of BSIM1 ".MODEL" lines suitable for inclusion
in a SPICE input file. Parameters marked below with an * in the l/w
column also have corresponding parameters with a length and width
dependency. For example, VFB is the basic parameter with units of
Volts, and LVFB and WVFB also exist and have units of Volt-Mmeter The
formula
@tex
$$
P = P_0 + { P_L \over L_{\rm effective} } + { P_W \over W_{\rm effective} }
$$
@end tex
@ifnottex
@example
P P
L W
P = P + ---------- + ----------
0
L W
effective effective
@end example
@end ifnottex
is used to evaluate the parameter for the actual device specified with
@tex
$$
L_{\rm effective} = L_{\rm input} - DL
$$
@end tex
@ifnottex
@example
L = L - DL
effective input
@end example
@end ifnottex
and
@tex
$$
W_{\rm effective} = W_{\rm input} - DW
$$
@end tex
@ifnottex
@example
W = W - DW
effective input
@end example
@end ifnottex
Note that unlike the other models in SPICE, the BSIM model is designed
for use with a process characterization system that provides all the
parameters, thus there are no defaults for the parameters, and leaving
one out is considered an error. For an example set of parameters and
the format of a process file, see the SPICE2 implementation notes[3].
For more information on BSIM2, see reference [5].
SPICE BSIM (level 4) parameters.
@example
name parameter units l/w
VFB flat-band voltage V *
PHI surface inversion potential V *
1/2
K1 body effect coefficient V *
K2 drain/source depletion charge-sharing coefficient - *
ETA zero-bias drain-induced barrier-lowering coefficient - *
2
MUZ zero-bias mobility cm /V-s
DL shortening of channel Mm
DW narrowing of channel Mm
-1
U0 zero-bias transverse-field mobility degradation coefficient V *
U1 zero-bias velocity saturation coefficient Mm/V *
2 2
X2MZ sens. of mobility to substrate bias at v =0 cm /V -s *
ds -1
X2E sens. of drain-induced barrier lowering effect to substrate bias V *
-1
X3E sens. of drain-induced barrier lowering effect to drain bias at V =V V *
ds dd -2
X2U0 sens. of transverse field mobility degradation effect to substrate bias V *
-2
X2U1 sens. of velocity saturation effect to substrate bias MmV *
2 2
MUS mobility at zero substrate bias and at V =V cm /V -s
ds dd 2 2
X2MS sens. of mobility to substrate bias at V =V cm /V -s *
ds dd 2 2
X3MS sens. of mobility to drain bias at V =V cm /V -s *
ds dd -2
X3U1 sens. of velocity saturation effect on drain bias at V =V MmV *
ds dd
TOX gate oxide thickness Mm
o
TEMP temperature at which parameters were measured C
VDD measurement bias range V
CGDO gate-drain overlap capacitance per meter channel width F/m
CGSO gate-source overlap capacitance per meter channel width F/m
CGBO gate-bulk overlap capacitance per meter channel length F/m
XPART gate-oxide capacitance-charge model flag N0 zero-bias subthreshold slope coefficient - *
NB sens. of subthreshold slope to substrate bias - *
ND sens. of subthreshold slope to drain bias - *
RSH drain and source diffusion sheet resistance Z/[]
2
JS source drain junction current density A/m
PB built in potential of source drain junction V
MJ Grading coefficient of source drain junction PBSW built in potential of source, drain junction sidewall V
MJSW grading coefficient of source drain junction sidewall 2
CJ Source drain junction capacitance per unit area F/m
CJSW source drain junction sidewall capacitance per unit length F/m
WDF source drain junction default width m
DELL Source drain junction length reduction m
@end example
XPART = 0 selects a 40/60 drain/source charge partition in saturation,
while XPART=1 selects a 0/100 drain/source charge partition.
ND, NG, and NS are the drain, gate, and source nodes, respectively.
MNAME is the model name, AREA is the area factor, and OFF indicates an
(optional) initial condition on the device for dc analysis. If the area
factor is omitted, a value of 1.0 is assumed. The (optional) initial
condition specification, using IC=VDS, VGS is intended for use with the
UIC option on the .TRAN control line, when a transient analysis is
desired starting from other than the quiescent operating point. See the
.IC control line for a better way to set initial conditions.
@node MESFETs, MESFET Models (NMF/PMF), MOSFET Models (NMOS/PMOS), Transistors and Diodes
@subsection MESFETs
General form:
@example
ZXXXXXXX ND NG NS MNAME <AREA> <OFF> <IC=VDS, VGS>
@end example
Examples:
@example
Z1 7 2 3 ZM1 OFF
@end example
@node MESFET Models (NMF/PMF), , MESFETs, Transistors and Diodes
@subsection MESFET Models (NMF/PMF)
The MESFET model is derived from the GaAs FET model of Statz et al. as
described in [11]. The dc characteristics are defined by the parameters
VTO, B, and BETA, which determine the variation of drain current with
gate voltage, ALPHA, which determines saturation voltage, and LAMBDA,
which determines the output conductance. The formula are given by:
@tex
$$
\cases{I_d = {B (V_{gs} - V_T)^2 \over 1 + b(V_{gs} - V_T)}
\left| 1 - \left| 1 - A {V_{ds} \over 3 } \right|^3 \right|
(1 + L V_{ds}) & for $0 < V_{ds} < 3/A$ \cr
I_d = {B (V_{gs} - V_T)^2 \over 1 + b(V_{gs} - V_T)}
(1 + L V_{ds}) & for $V_{ds} > 3/A$ \cr}
$$
@end tex
@ifnottex
@example
3
2
B (V -V ) | | V | | 3
gs T ds _
I = --------------- |1 - |1-A---| |(1 + L V ) for 0 < V <
d ds ds
1 + b(V - V ) | | 3 | | A
gs T
2
B (V -V ) 3
gs T _
I = ---------------(1 + L V ) for V >
d ds ds
1 + b(V - V ) A
gs T
@end example
@end ifnottex
Two ohmic resistances, RD and RS, are included. Charge storage is
modeled by total gate charge as a function of gate-drain and gate-source
voltages and is defined by the parameters CGS, CGD, and PB.
@example
name parameter units default example area
1 VTO pinch-off voltage V -2.0 -2.0
2
2 BETA transconductance parameter A/V 1.0e-4 1.0e-3 *
3 B doping tail extending parameter 1/V 0.3 0.3 *
4 ALPHA saturation voltage parameter 1/V 2 2 *
5 LAMBDA channel-length modulation
parameter 1/V 0 1.0e-4
6 RD drain ohmic resistance Z 0 100 *
7 RS source ohmic resistance Z 0 100 *
8 CGS zero-bias G-S junction capacitance F 0 5pF *
9 CGD zero-bias G-D junction capacitance F 0 1pF *
10 PB gate junction potential V 1 0.6
11 KF flicker noise coefficient - 0
12 AF flicker noise exponent - 1
13 FC coefficient for forward-bias - 0.5
depletion capacitance formula
@end example
@node Analyses and Output Control, Interactive Interpreter, Circuit Elements and Models, Top
@chapter Analyses and Output Control
The following command lines are for specifying analyses or plots within
the circuit description file. Parallel commands exist in the
interactive command interpreter (detailed in the following section).
Specifying analyses and plots (or tables) in the input file is useful
for batch runs. Batch mode is entered when either the -b option is
given or when the default input source is redirected from a file. In
batch mode, the analyses specified by the control lines in the input
file (e.g. ".ac", ".tran", etc.) are immediately executed (unless
".control" lines exists; see the section on the interactive command
interpretor). If the -r rawfile option is given then all data generated
is written to a Spice3 rawfile. The rawfile may be read by either the
interactive mode of Spice3 or by nutmeg; see the previous section for
details. In this case, the .SAVE line (see below) may be used to record
the value of internal device variables (see Appendix B).
If a rawfile is not specified, then output plots (in "line-printer"
form) and tables can be printed according to the .PRINT, .PLOT, and
.FOUR control lines, described next. .PLOT, .PRINT, and .FOUR lines are
meant for compatibility with Spice2.
@menu
* Simulator Variables (.OPTIONS)::
* Initial Conditions::
* Analyses::
* Batch Output::
@end menu
@node Simulator Variables (.OPTIONS), Initial Conditions, Analyses and Output Control, Analyses and Output Control
@section Simulator Variables (.OPTIONS)
Various parameters of the simulations available in Spice3 can be altered
to control the accuracy, speed, or default values for some devices.
These parameters may be changed via the "set" command (described later
in the section on the interactive front-end) or via the ".OPTIONS" line:
General form:
@example
.OPTIONS OPT1 OPT2 ... (or OPT=OPTVAL ...)
@end example
Examples:
@example
.OPTIONS RELTOL=.005 TRTOL=8
@end example
The options line allows the user to reset program control and user
options for specific simulation purposes. Additional options for Nutmeg
may be specified as well and take effect when Nutmeg reads the input
file. Options specified to Nutmeg via the 'set' command are also passed
on to SPICE3 as if specified on a .OPTIONS line. See the following
section on the interactive command interpreter for the parameters which
may be set with a .OPTIONS line and the format of the 'set' command.
Any combination of the following options may be included, in any order.
'x' (below) represents some positive number.
@vtable @code
@item ABSTOL=x
resets the absolute current error tolerance of the program. The default
value is 1 picoamp.
@item BADMOS3
Use the older version of the MOS3 model with the "kappa" discontinuity.
@item CHGTOL=x
resets the charge tolerance of the program. The default value is
1.0e-14.
@item DEFAD=x
resets the value for MOS drain diffusion area; the default is 0.0.
@item DEFAS=x
resets the value for MOS source diffusion area; the default is 0.0.
@item DEFL=x
resets the value for MOS channel length; the default is 100.0
micrometer.
@item DEFW=x
resets the value for MOS channel width; the default is 100.0 micrometer.
@item GMIN=x
resets the value of GMIN, the minimum conductance allowed by the
program. The default value is 1.0e-12.
@item ITL1=x
resets the dc iteration limit. The default is 100.
@item ITL2=x
resets the dc transfer curve iteration limit. The default is 50.
@item ITL3=x
resets the lower transient analysis iteration limit. the default value
is 4. (Note: not implemented in Spice3).
@item ITL4=x
resets the transient analysis timepoint iteration limit. the default is
10.
@item ITL5=x
resets the transient analysis total iteration limit. the default is
5000. Set ITL5=0 to omit this test. (Note: not implemented in Spice3).
@item KEEPOPINFO
Retain the operating point information when either an AC, Distortion, or
Pole-Zero analysis is run. This is particularly useful if the circuit
is large and you do not want to run a (redundant) ".OP" analysis.
@item METHOD=name
sets the numerical integration method used by SPICE. Possible names are
"Gear" or "trapezoidal" (or just "trap"). The default is trapezoidal.
@item PIVREL=x
resets the relative ratio between the largest column entry and an
acceptable pivot value. The default value is 1.0e-3. In the numerical
pivoting algorithm the allowed minimum pivot value is determined by
EPSREL=AMAX1(PIVREL*MAXVAL, PIVTOL) where MAXVAL is the maximum element
in the column where a pivot is sought (partial pivoting).
@item PIVTOL=x
resets the absolute minimum value for a matrix entry to be accepted as a
pivot. The default value is 1.0e-13.
@item RELTOL=x
resets the relative error tolerance of the program. The default value
is 0.001 (0.1%).
@item TEMP=x
Resets the operating temperature of the circuit. The default value is
27 deg C (300 deg K). TEMP can be overridden by a temperature
specification on any temperature dependent instance.
@item TNOM=x
resets the nominal temperature at which device parameters are measured.
The default value is 27 deg C (300 deg K). TNOM can be overridden by a
specification on any temperature dependent device model.
@item TRTOL=x
resets the transient error tolerance. The default value is 7.0. This
parameter is an estimate of the factor by which SPICE overestimates the
actual truncation error.
@item TRYTOCOMPACT
Applicable only to the LTRA model. When specified, the simulator tries
to condense LTRA transmission lines' past history of input voltages and
currents.
@item VNTOL=x
resets the absolute voltage error tolerance of the program. The default
value is 1 microvolt.
@end vtable
In addition, the following options have the listed effect when operating
in spice2 emulation mode:
@table @code
@item ACCT
causes accounting and run time statistics to be printed
@item LIST
causes the summary listing of the input data to be printed
@item NOMOD
suppresses the printout of the model parameters
@item NOPAGE
suppresses page ejects
@item NODE
causes the printing of the node table.
@item OPTS
causes the option values to be printed.
@end table
@node Initial Conditions, Analyses, Simulator Variables (.OPTIONS), Analyses and Output Control
@section Initial Conditions
@menu
* Specify Initial Node Voltage Guesses::
* Set Initial Conditions::
@end menu
@node Specify Initial Node Voltage Guesses, Set Initial Conditions, Initial Conditions, Initial Conditions
@subsection .NODESET: Specify Initial Node Voltage Guesses
General form:
@example
.NODESET V(NODNUM)=VAL V(NODNUM)=VAL ...
@end example
Examples:
@example
.NODESET V(12)=4.5 V(4)=2.23
@end example
The Nodeset line helps the program find the dc or initial transient
solution by making a preliminary pass with the specified nodes held to
the given voltages. The restriction is then released and the iteration
continues to the true solution. The .NODESET line may be necessary for
convergence on bistable or a-stable circuits. In general, this line
should not be necessary.
@node Set Initial Conditions, , Specify Initial Node Voltage Guesses, Initial Conditions
@subsection .IC: Set Initial Conditions
General form:
@example
.IC V(NODNUM)=VAL V(NODNUM)=VAL ...
@end example
Examples:
@example
.IC V(11)=5 V(4)=-5 V(2)=2.2
@end example
The IC line is for setting transient initial conditions. It has two
different interpretations, depending on whether the UIC parameter is
specified on the .TRAN control line. Also, one should not confuse this
line with the .NODESET line. The .NODESET line is only to help dc
convergence, and does not affect final bias solution (except for
multi-stable circuits). The two interpretations of this line are as
follows:
@enumerate
@item
When the UIC parameter is specified on the .TRAN line, then the node
voltages specified on the .IC control line are used to compute the
capacitor, diode, BJT, JFET, and MOSFET initial conditions. This is
equivalent to specifying the IC=... parameter on each device line, but
is much more convenient. The IC=... parameter can still be specified
and takes precedence over the .IC values. Since no dc bias (initial
transient) solution is computed before the transient analysis, one
should take care to specify all dc source voltages on the .IC control
line if they are to be used to compute device initial conditions.
@item
When the UIC parameter is not specified on the .TRAN control line, the
dc bias (initial transient) solution is computed before the transient
analysis. In this case, the node voltages specified on the .IC control
line is forced to the desired initial values during the bias solution.
During transient analysis, the constraint on these node voltages is
removed. This is the preferred method since it allows SPICE to compute
a consistent dc solution.
@end enumerate
@node Analyses, Batch Output, Initial Conditions, Analyses and Output Control
@section Analyses
@menu
* AC Small-Signal AC Analysis::
* DC Transfer Function::
* DISTRO Distortion Analysis::
* NOISE Noise Analysis::
* OP Operating Point Analysis::
* PZ Pole-Zero Analysis::
* SENS; DC or Small-Signal AC Sensitivity Analysis::
* TF Transfer Function Analysis::
* TRAN Transient Analysis::
@end menu
@node AC Small-Signal AC Analysis, DC Transfer Function, Analyses, Analyses
@subsection .AC: Small-Signal AC Analysis
General form:
@example
.AC DEC ND FSTART FSTOP
.AC OCT NO FSTART FSTOP
.AC LIN NP FSTART FSTOP
@end example
Examples:
@example
.AC DEC 10 1 10K
.AC DEC 10 1K 100MEG
.AC LIN 100 1 100HZ
@end example
DEC stands for decade variation, and ND is the number of points per
decade. OCT stands for octave variation, and NO is the number of points
per octave. LIN stands for linear variation, and NP is the number of
points. FSTART is the starting frequency, and FSTOP is the final
frequency. If this line is included in the input file, SPICE performs
an AC analysis of the circuit over the specified frequency range. Note
that in order for this analysis to be meaningful, at least one
independent source must have been specified with an ac value.
@node DC Transfer Function, DISTRO Distortion Analysis, AC Small-Signal AC Analysis, Analyses
@subsection .DC: DC Transfer Function
General form:
@example
.DC SRCNAM VSTART VSTOP VINCR [SRC2 START2 STOP2 INCR2]
@end example
Examples:
@example
.DC VIN 0.25 5.0 0.25
.DC VDS 0 10 .5 VGS 0 5 1
.DC VCE 0 10 .25 IB 0 10U 1U
@end example
The DC line defines the dc transfer curve source and sweep limits (again
with capacitors open and inductors shorted). SRCNAM is the name of an
independent voltage or current source. VSTART, VSTOP, and VINCR are the
starting, final, and incrementing values respectively. The first
example causes the value of the voltage source VIN to be swept from 0.25
Volts to 5.0 Volts in increments of 0.25 Volts. A second source (SRC2)
may optionally be specified with associated sweep parameters. In this
case, the first source is swept over its range for each value of the
second source. This option can be useful for obtaining semiconductor
device output characteristics. See the second example circuit
description in Appendix A.
@node DISTRO Distortion Analysis, NOISE Noise Analysis, DC Transfer Function, Analyses
@subsection .DISTO: Distortion Analysis
General form:
@example
.DISTO DEC ND FSTART FSTOP <F2OVERF1>
.DISTO OCT NO FSTART FSTOP <F2OVERF1>
.DISTO LIN NP FSTART FSTOP <F2OVERF1>
@end example
Examples:
@example
.DISTO DEC 10 1kHz 100Mhz
.DISTO DEC 10 1kHz 100Mhz 0.9
@end example
The Disto line does a small-signal distortion analysis of the circuit.
A multi-dimensional Volterra series analysis is done using
multi-dimensional Taylor series to represent the nonlinearities at the
operating point. Terms of up to third order are used in the series
expansions.
If the optional parameter F2OVERF1 is not specified, .DISTO does a
harmonic analysis - i.e., it analyses distortion in the circuit using
only a single input frequency @math{F_1}, which is swept as specified by
arguments of the .DISTO command exactly as in the .AC command. Inputs
at this frequency may be present at more than one input source, and
their magnitudes and phases are specified by the arguments of the
DISTOF1 keyword in the input file lines for the input sources (see the
description for independent sources). (The arguments of the DISTOF2
keyword are not relevant in this case).
The analysis produces information about the A.C. values of all node
voltages and branch currents at the harmonic frequencies @math{2F_1} and
@math{3F_1}, vs. the input frequency @math{F_1} as it is swept. (A
value of 1 (as a complex distortion output) signifies
@math{\cos(2J(2F_1)t)} at @math{2F_1} and @math{\cos(2J(3F_1)t)} at
@math{3F_1}, using the convention that 1 at the input fundamental
frequency is equivalent to @math{\cos(2JF_1t)}.) The distortion
component desired (@math{2F_1} or @math{3F_1}) can be selected using
commands in nutmeg, and then printed or plotted. (Normally, one is
interested primarily in the magnitude of the harmonic components, so the
magnitude of the AC distortion value is looked at). It should be noted
that these are the A.C. values of the actual harmonic components, and
are not equal to HD2 and HD3. To obtain HD2 and HD3, one must divide by
the corresponding A.C. values at @math{F_1}, obtained from an .AC line.
This division can be done using nutmeg commands.
If the optional F2OVERF1 parameter is specified, it should be a real
number between (and not equal to) 0.0 and 1.0; in this case, .DISTO does
a spectral analysis. It considers the circuit with sinusoidal inputs at
two different frequencies @math{F_1} and F_2. @math{F_1} is swept
according to the .DISTO control line options exactly as in the .AC
control line. @math{F_2} is kept fixed at a single frequency as @math{F_1}
sweeps - the value at which it is kept fixed is equal to F2OVERF1 times
FSTART. Each independent source in the circuit may potentially have two
(superimposed) sinusoidal inputs for distortion, at the frequencies
@math{F_1} and F_2. The magnitude and phase of the @math{F_1} component
are specified by the arguments of the DISTOF1 keyword in the source's
input line (see the description of independent sources); the magnitude
and phase of the @math{F_2} component are specified by the arguments of the
DISTOF2 keyword. The analysis produces plots of all node
voltages/branch currents at the intermodulation product frequencies
@math{F_1 + F_2}, @math{F_1 - F_2}, and @math{(2 F_1) - F_2}, vs the
swept frequency @math{F_1}. The IM product of interest may be selected
using the setplot command, and displayed with the print and plot
commands. It is to be noted as in the harmonic analysis case, the
results are the actual AC voltages and currents at the intermodulation
frequencies, and need to be normalized with respect to .AC values to
obtain the IM parameters.
If the DISTOF1 or DISTOF2 keywords are missing from the description of
an independent source, then that source is assumed to have no input at
the corresponding frequency. The default values of the magnitude and
phase are 1.0 and 0.0 respectively. The phase should be specified in
degrees.
It should be carefully noted that the number F2OVERF1 should ideally be
an irrational number, and that since this is not possible in practice,
efforts should be made to keep the denominator in its fractional
representation as large as possible, certainly above 3, for accurate
results (i.e., if F2OVERF1 is represented as a fraction @math{A/B},
where @math{A} and @math{B} are integers with no common factors,
@math{B} should be as large as possible; note that @math{A < B} because
F2OVERF1 is constrained to be @math{< 1}). To illustrate why, consider
the cases where F2OVERF1 is 49/100 and 1/2. In a spectral analysis, the
outputs produced are at @math{F_1 + F_2}, @math{F_1 - F_2} and @math{2
F_1 - F_2}. In the latter case, @math{F_1 - F_2 = F_2}, so the result
at the @math{F_1 - F_2} component is erroneous because there is the
strong fundamental @math{F_2} component at the same frequency. Also,
@math{F_1 + F_2 = 2 F_1 - F_2} in the latter case, and each result is
erroneous individually. This problem is not there in the case where
F2OVERF1 = 49/100, because @math{F_1-F_2 = 51/100} @math{F_1 < > 49/100}
@math{F_1 = F_2}. In this case, there are two very closely spaced
frequency components at @math{F_2} and @math{F_1 - F_2}. One of the
advantages of the Volterra series technique is that it computes
distortions at mix frequencies expressed symbolically (i.e. @math{n F_1
+ m F_2}), therefore one is able to obtain the strengths of distortion
components accurately even if the separation between them is very small,
as opposed to transient analysis for example. The disadvantage is of
course that if two of the mix frequencies coincide, the results are not
merged together and presented (though this could presumably be done as a
postprocessing step). Currently, the interested user should keep track
of the mix frequencies himself or herself and add the distortions at
coinciding mix frequencies together should it be necessary.
@node NOISE Noise Analysis, OP Operating Point Analysis, DISTRO Distortion Analysis, Analyses
@subsection .NOISE: Noise Analysis
General form:
@example
.NOISE V(OUTPUT <,REF>) SRC ( DEC | LIN | OCT ) PTS FSTART FSTOP
+ <PTS_PER_SUMMARY>
@end example
Examples:
@example
.NOISE V(5) VIN DEC 10 1kHZ 100Mhz
.NOISE V(5,3) V1 OCT 8 1.0 1.0e6 1
@end example
The Noise line does a noise analysis of the circuit. OUTPUT is the node
at which the total output noise is desired; if REF is specified, then
the noise voltage V(OUTPUT) - V(REF) is calculated. By default, REF is
assumed to be ground. SRC is the name of an independent source to which
input noise is referred. PTS, FSTART and FSTOP are .AC type parameters
that specify the frequency range over which plots are desired.
PTS_PER_SUMMARY is an optional integer; if specified, the noise
contributions of each noise generator is produced every PTS_PER_SUMMARY
frequency points.
The .NOISE control line produces two plots - one for the Noise Spectral
Density curves and one for the total Integrated Noise over the specified
frequency range. All noise voltages/currents are in squared units
(V@math{^2} /Hz and A@math{^2}/Hz for spectral density, V@math{^2} and
A@math{^2} for integrated noise).
@node OP Operating Point Analysis, PZ Pole-Zero Analysis, NOISE Noise Analysis, Analyses
@subsection .OP: Operating Point Analysis
General form:
@example
.OP
@end example
The inclusion of this line in an input file directs SPICE to determine
the dc operating point of the circuit with inductors shorted and
capacitors opened. Note: a DC analysis is automatically performed prior
to a transient analysis to determine the transient initial conditions,
and prior to an AC small-signal, Noise, and Pole-Zero analysis to
determine the linearized, small-signal models for nonlinear devices (see
the KEEPOPINFO variable above).
@node PZ Pole-Zero Analysis, SENS; DC or Small-Signal AC Sensitivity Analysis, OP Operating Point Analysis, Analyses
@subsection .PZ: Pole-Zero Analysis
General form:
@example
.PZ NODE1 NODE2 NODE3 NODE4 CUR POL
.PZ NODE1 NODE2 NODE3 NODE4 CUR ZER
.PZ NODE1 NODE2 NODE3 NODE4 CUR PZ
.PZ NODE1 NODE2 NODE3 NODE4 VOL POL
.PZ NODE1 NODE2 NODE3 NODE4 VOL ZER
.PZ NODE1 NODE2 NODE3 NODE4 VOL PZ
@end example
Examples:
@example
.PZ 1 0 3 0 CUR POL
.PZ 2 3 5 0 VOL ZER
.PZ 4 1 4 1 CUR PZ
@end example
CUR stands for a transfer function of the type (output voltage)/(input
current) while VOL stands for a transfer function of the type (output
voltage)/(input voltage). POL stands for pole analysis only, ZER for
zero analysis only and PZ for both. This feature is provided mainly
because if there is a nonconvergence in finding poles or zeros, then, at
least the other can be found. Finally, NODE1 and NODE2 are the two
input nodes and NODE3 and NODE4 are the two output nodes. Thus, there
is complete freedom regarding the output and input ports and the type of
transfer function.
In interactive mode, the command syntax is the same except that the
first field is PZ instead of .PZ. To print the results, one should use
the command 'print all'.
@node SENS; DC or Small-Signal AC Sensitivity Analysis, TF Transfer Function Analysis, PZ Pole-Zero Analysis, Analyses
@subsection .SENS: DC or Small-Signal AC Sensitivity Analysis
General form:
@example
.SENS OUTVAR
.SENS OUTVAR AC DEC ND FSTART FSTOP
.SENS OUTVAR AC OCT NO FSTART FSTOP
.SENS OUTVAR AC LIN NP FSTART FSTOP
@end example
Examples:
@example
.SENS V(1,OUT)
.SENS V(OUT) AC DEC 10 100 100k
.SENS I(VTEST)
@end example
The sensitivity of OUTVAR to all non-zero device parameters is
calculated when the SENS analysis is specified. OUTVAR is a circuit
variable (node voltage or voltage-source branch current). The first
form calculates sensitivity of the DC operating-point value of OUTVAR.
The second form calculates sensitivity of the AC values of OUTVAR. The
parameters listed for AC sensitivity are the same as in an AC analysis
(see ".AC" above). The output values are in dimensions of change in
output per unit change of input (as opposed to percent change in output
or per percent change of input).
@node TF Transfer Function Analysis, TRAN Transient Analysis, SENS; DC or Small-Signal AC Sensitivity Analysis, Analyses
@subsection .TF: Transfer Function Analysis
General form:
@example
.TF OUTVAR INSRC
@end example
Examples:
@example
.TF V(5, 3) VIN
.TF I(VLOAD) VIN
@end example
The TF line defines the small-signal output and input for the dc
small-signal analysis. OUTVAR is the smallsignal output variable and
INSRC is the small-signal input source. If this line is included, SPICE
computes the dc small-signal value of the transfer function
(output/input), input resistance, and output resistance. For the first
example, SPICE would compute the ratio of V(5, 3) to VIN, the
small-signal input resistance at VIN, and the smallsignal output
resistance measured across nodes 5 and 3.
@node TRAN Transient Analysis, , TF Transfer Function Analysis, Analyses
@subsection .TRAN: Transient Analysis
General form:
@example
.TRAN TSTEP TSTOP <TSTART <TMAX>>
@end example
Examples:
@example
.TRAN 1NS 100NS
.TRAN 1NS 1000NS 500NS
.TRAN 10NS 1US
@end example
TSTEP is the printing or plotting increment for lineprinter output. For
use with the post-processor, TSTEP is the suggested computing increment.
TSTOP is the final time, and TSTART is the initial time. If TSTART is
omitted, it is assumed to be zero. The transient analysis always begins
at time zero. In the interval <zero, TSTART>, the circuit is analyzed
(to reach a steady state), but no outputs are stored. In the interval
<TSTART, TSTOP>, the circuit is analyzed and outputs are stored. TMAX
is the maximum stepsize that SPICE uses; for default, the program
chooses either TSTEP or (TSTOP-TSTART)/50.0, whichever is smaller. TMAX
is useful when one wishes to guarantee a computing interval which is
smaller than the printer increment, TSTEP.
UIC (use initial conditions) is an optional keyword which indicates that
the user does not want SPICE to solve for the quiescent operating point
before beginning the transient analysis. If this keyword is specified,
SPICE uses the values specified using IC=... on the various elements as
the initial transient condition and proceeds with the analysis. If the
.IC control line has been specified, then the node voltages on the .IC
line are used to compute the initial conditions for the devices. Look
at the description on the .IC control line for its interpretation when
UIC is not specified.
@node Batch Output, , Analyses, Analyses and Output Control
@section Batch Output
@menu
* SAVE::
* PRINT::
* PLOT::
* FOUR Fourier Analysis of Transient Analysis Output::
@end menu
@node SAVE, PRINT, Batch Output, Batch Output
@subsection .SAVE Lines
General form:
@example
.SAVE vector vector vector ...
@end example
Examples:
@example
.SAVE i(vin) input output
.SAVE @@m1[id]
@end example
The vectors listed on the .SAVE line are recorded in the rawfile for use
later with spice3 or nutmeg (nutmeg is just the data-analysis half of
spice3, without the ability to simulate). The standard vector names are
accepted. If no .SAVE line is given, then the default set of vectors
are saved (node voltages and voltage source branch currents). If .SAVE
lines are given, only those vectors specified are saved. For more
discussion on internal device data, see Appendix B. See also the
section on the interactive command interpretor for information on how to
use the rawfile.
@node PRINT, PLOT, SAVE, Batch Output
@subsection .PRINT Lines
General form:
@example
.PRINT PRTYPE OV1 <OV2 ... OV8>
@end example
Examples:
@example
.PRINT TRAN V(4) I(VIN)
.PRINT DC V(2) I(VSRC) V(23, 17)
.PRINT AC VM(4, 2) VR(7) VP(8, 3)
@end example
The Print line defines the contents of a tabular listing of one to eight
output variables. PRTYPE is the type of the analysis (DC, AC, TRAN,
NOISE, or DISTO) for which the specified outputs are desired. The form
for voltage or current output variables is the same as given in the
previous section for the print command; Spice2 restricts the output
variable to the following forms (though this restriction is not enforced
by Spice3):
@table @code
@item V(N1<,N2>)
specifies the voltage difference between nodes N1 and N2. If N2 (and
the preceding comma) is omitted, ground (0) is assumed. See the print
command in the previous section for more details. For compatibility
with spice2, the following five additional values can be accessed for
the ac analysis by replacing the "V" in V(N1,N2) with:
@example
VR - real part
VI - imaginary part
VM - magnitude
VP - phase
VDB - 20 log10(magnitude)
@end example
@item I(VXXXXXXX)
specifies the current flowing in the independent voltage source named
VXXXXXXX. Positive current flows from the positive node, through the
source, to the negative node. For the ac analysis, the corresponding
replacements for the letter I may be made in the same way as described
for voltage outputs.
@end table
Output variables for the noise and distortion analyses have a different
general form from that of the other analyses.
There is no limit on the number of .PRINT lines for each type of
analysis.
@node PLOT, FOUR Fourier Analysis of Transient Analysis Output, PRINT, Batch Output
@subsection .PLOT Lines
General form:
@example
.PLOT PLTYPE OV1 <(PLO1, PHI1)> <OV2 <(PLO2, PHI2)> ... OV8>
@end example
Examples:
@example
.PLOT DC V(4) V(5) V(1)
.PLOT TRAN V(17, 5) (2, 5) I(VIN) V(17) (1, 9)
.PLOT AC VM(5) VM(31, 24) VDB(5) VP(5)
.PLOT DISTO HD2 HD3(R) SIM2
.PLOT TRAN V(5, 3) V(4) (0, 5) V(7) (0, 10)
@end example
The Plot line defines the contents of one plot of from one to eight
output variables. PLTYPE is the type of analysis (DC, AC, TRAN, NOISE,
or DISTO) for which the specified outputs are desired. The syntax for
the OVI is identical to that for the .PRINT line and for the plot
command in the interactive mode.
The overlap of two or more traces on any plot is indicated by the letter
X.
When more than one output variable appears on the same plot, the first
variable specified is printed as well as plotted. If a printout of all
variables is desired, then a companion .PRINT line should be included.
There is no limit on the number of .PLOT lines specified for each type of analysis.
@node FOUR Fourier Analysis of Transient Analysis Output, , PLOT, Batch Output
@subsection .FOUR: Fourier Analysis of Transient Analysis Output
General form:
@example
.FOUR FREQ OV1 <OV2 OV3 ...>
@end example
Examples:
@example
.FOUR 100K V(5)
@end example
The Four (or Fourier) line controls whether SPICE performs a Fourier
analysis as a part of the transient analysis. FREQ is the fundamental
frequency, and OV1, desired. The Fourier analysis is performed over the
interval <TSTOP-period, TSTOP>, where TSTOP is the final time specified
for the transient analysis, and period is one period of the fundamental
frequency. The dc component and the first nine harmonics are
determined. For maximum accuracy, TMAX (see the .TRAN line) should be
set to period/100.0 (or less for very high-Q circuits).
@node Interactive Interpreter, Bibliography, Analyses and Output Control, Top
@chapter Interactive Interpreter
Spice3 consists of a simulator and a front-end for data analysis and
plotting. The front-end may be run as a separate "stand-alone" program
under the name Nutmeg.
Nutmeg will read in the "raw" data output file created by spice -r or
with the write command in an interactive Spice3 session. Nutmeg or
interactive Spice3 can plot data from a simulation on a graphics
terminal or a workstation display. Most of the commands available in
the interactive Spice3 front end are available in nutmeg; where this is
not the case, Spice-only commands have been marked with an asterisk
("*"). Note that the raw output file is different from the data that
Spice2 writes to the standard output, which may also be produced by
spice3 with the "-b" command line option.
Spice and Nutmeg use the X Window System for plotting if they find the
environment variable DISPLAY. Otherwise, a graphics-terminal
independent interface (MFB) is used. If you are using X on a
workstation, the DISPLAY variable should already be set; if you want to
display graphics on a system different from the one you are running
Spice3 or Nutmeg on, DISPLAY should be of the form "machine:0.0". See
the appropriate documentation on the X Window Sytem for more details.
Command Synopsis
@example
spice [ -n ] [ -t term ] [ -r rawfile] [ -b ] [ -i ] [ input file ... ]
nutmeg [ - ] [ -n ] [ -t term ] [ datafile ... ]
@end example
Options are:
@table @code
@item -
Don't try to load the default data file ("rawspice.raw") if no other
files are given. Nutmeg only.
@item -n (or -N)
Don't try to source the file ".spiceinit" upon startup. Normally spice
and nutmeg try to find the file in the current directory, and if it is
not found then in the user's home directory.
@item -t term (or -T term)
The program is being run on a terminal with mfb name term.
@item -b (or -B)
Run in batch mode. Spice3 reads the default input source (e.g.
keyboard) or reads the given input file and performs the analyses
specified; output is either Spice2-like line-printer plots ("ascii
plots") or a spice rawfile. See the following section for details.
Note that if the input source is not a terminal (e.g. using the IO
redirection notation of "<") Spice3 defaults to batch mode (-i
overrides). This option is valid for Spice3 only.
@item -s (or -S)
Run in server mode. This is like batch mode, except that a temporary
rawfile is used and then written to the standard output, preceded by a
line with a single "@@", after the simulation is done. This mode is used
by the spice daemon. This option is valid for Spice3 only.
@item -i (or -I)
Run in interactive mode. This is useful if the standard input is not a
terminal but interactive mode is desired. Command completion is not
available unless the standard input is a terminal, however. This option
is valid for Spice3 only.
@item -r rawfile (or -P rawfile)
Use rawfile as the default file into which the results of the simulation
are saved. This option is valid for Spice3 only.
@end table
Further arguments to spice are taken to be Spice3 input files, which are
read and saved (if running in batch mode then they are run immediately).
Spice3 accepts most Spice2 input file, and output ascii plots, fourier
analyses, and node printouts as specified in .plot, .four, and .print
cards. If an out parameter is given on a .width card, the effect is the
same as set width = .... Since Spice3 ascii plots do not use multiple
ranges, however, if vectors together on a .plot card have different
ranges they are not provide as much information as they would in Spice2.
The output of Spice3 is also much less verbose than Spice2, in that the
only data printed is that requested by the above cards.
For nutmeg, further arguments are taken to be data files in binary or
ascii format (see sconvert(1)) which are loaded into nutmeg. If the
file is in binary format, it may be only partially completed (useful for
examining Spice2 output before the simulation is finished). One file
may contain any number of data sets from different analyses.
@menu
* Expressions::
* Command Interpretation::
* Commands::
* Variables::
* Bugs::
@end menu
@node Expressions, Command Interpretation, Interactive Interpreter, Interactive Interpreter
@section Expressions, Functions, and Constants
Spice and Nutmeg data is in the form of vectors: time, voltage, etc.
Each vector has a type, and vectors can be operated on and combined
algebraicly in ways consistent with their types. Vectors are normally
created when a data file is read in (see the load command below), and
when the initial datafile is loaded. They can also be created with the
let command.
An expression is an algebraic formula involving vectors and scalars (a
scalar is a vector of length 1) and the following operations:
@example
+ - * / ^ %
@end example
% is the modulo operator, and the comma operator has two meanings: if it
is present in the argument list of a userdefinable function, it serves
to separate the arguments. Otherwise, the term @code{x , y} is
synonymous with @code{x + j(y)}.
Also available are the logical operations & (and), | (or), ! (not), and
the relational operations <, >, >=, <=, =, and <> (not equal). If used
in an algebraic expression they work like they would in C, producing
values of 0 or 1. The relational operators have the following synonyms:
@example
gt >
lt <
ge >=
le <=
ne <>
eq =
and &
or |
not !
@end example
These are useful when < and > might be confused with IO redirection
(which is almost always).
The following functions are available:
@ftable @code
@item mag(vector)
The magnitude of vector
@item ph(vector)
The phase of vector
@item j(vector)
i (sqrt(-1)) times vector
@item real(vector)
The real component of vector
@item imag(vector)
The imaginary part of vector
@item db(vector)
20 log10(mag(vector))
@item log(vector)
The logarithm (base 10) of vector
@item ln(vector)
The natural logarithm (base e) of vector
@item exp(vector)
e to the vector power
@item abs(vector)
The absolute value of vector.
@item sqrt(vector)
The square root of vector.
@item sin(vector)
The sine of vector.
@item cos(vector)
The cosine of vector.
@item tan(vector)
The tangent of vector.
@item atan(vector)
The inverse tangent of vector.
@item norm(vector)
The vector normalized to 1 (i.e, the largest magnitude of any component
is 1).
@item rnd(vector)
A vector with each component a random integer between 0 and the absolute
value of the vectors's corresponding com ponent.
@item mean(vector)
The result is a scalar (a length 1 vec tor) that is the mean of the
elements of vector.
@item vector(number)
The result is a vector of length number, with elements 0, 1, ... number
- 1. If number is a vector then just the first element is taken, and if
it isn't an in teger then the floor of the magnitude is used.
@item length(vector)
The length of vector.
@item interpolate(plot.vector)
The result of interpolating the named vector onto the scale of
the current plot. This function uses the variable polydegree to
determine the degree of interpolation.
@item deriv(vector)
Calculates the derivative of the given vector. This uses numeric
differentia tion by interpolating a polynomial and may not produce
satisfactory results (particularly with iterated differentiation). The
implementation only caculates the dirivative with respect to the real
componant of that vector's scale.
@end ftable
A vector may be either the name of a vector already defined or a
floating-point number (a scalar). A number may be written in any format
acceptable to SPICE, such as 14.6Meg or -1.231e-4. Note that you can
either use scientific notation or one of the abbreviations like MEG or
G, but not both. As with SPICE, a number may have trailing alphabetic
characters after it.
The notation expr [num] denotes the num'th element of expr. For
multi-dimensional vectors, a vector of one less dimension is returned.
Also for multi-dimensional vectors, the notation expr[m][n] will return
the nth element of the mth subvector. To get a subrange of a vector,
use the form expr[lower, upper].
To reference vectors in a plot that is not the current plot (see the
setplot command, below), the notation plotname.vecname can be used.
Either a plotname or a vector name may be the wildcard all. If the
plotname is all, matching vectors from all plots are specified, and if
the vector name is all, all vectors in the specified plots are
referenced. Note that you may not use binary operations on expressions
involving wildcards - it is not obvious what all + all should denote,
for instance. Thus some (contrived) examples of expressions are:
@example
cos(TIME) + db(v(3))
sin(cos(log([1 2 3 4 5 6 7 8 9 10])))
TIME * rnd(v(9)) - 15 * cos(vin#branch) ^ [7.9e5 8]
not ((ac3.FREQ[32] & tran1.TIME[10]) gt 3)
@end example
Vector names in spice may have a name such as @@name[param], where name
is either the name of a device instance or model. This denotes the
value of the param parameter of the device or model. See Appendix B for
details of what parameters are available. The value is a vector of
length 1. This function is also available with the show command, and is
available with variables for convenience for command scripts.
There are a number of pre-defined constants in nutmeg. They are:
@vtable @code
@item pi
J (3.14159...)
@item e
The base of natural logarithms (2.71828...)
@item c
The speed of light (299,792,500 m/sec)
@item i
The square root of -1
@item kelvin
Absolute 0 in Centigrade (-273.15 <20> C)
@item echarge
The charge on an electron (1.6021918e-19 C)
@item boltz
Boltzman's constant (1.3806226e-23)
@item planck
Planck's constant (h = 6.626200e-34)
@end vtable
These are all in MKS units. If you have another variable with a name
that conflicts with one of these then it takes precedence.
@menu
* Command Interpretation::
* Commands::
* Variables::
* Bugs::
@end menu
@node Command Interpretation, Commands, Expressions, Interactive Interpreter
@section Command Interpretation
If a word is typed as a command, and there is no built-in command with
that name, the directories in the sourcepath list are searched in order
for the file. If it is found, it is read in as a command file (as if it
were sourced). Before it is read, however, the variables argc and argv
are set to the number of words following the filename on the command
line, and a list of those words respectively. After the file is
finished, these variables are unset. Note that if a command file calls
another, it must save its argv and argc since they are altered. Also,
command files may not be re-entrant since there are no local variables.
(Of course, the procedures may explicitly manipulate a stack...) This
way one can write scripts analogous to shell scripts for nutmeg and
Spice3.
Note that for the script to work with Spice3, it must begin with a blank
line (or whatever else, since it is thrown away) and then a line with
.control on it. This is an unfortunate result of the source command
being used for both circuit input and command file execution. Note also
that this allows the user to merely type the name of a circuit file as a
command and it is automatically run. The commands are executed
immediately, without running any analyses that may be spicified in the
circuit (to execute the analyses before the script executes, include a
"run" command in the script).
There are various command scripts installed in
/usr/local/lib/spice/scripts (or whatever the path is on your machine),
and the default sourcepath includes this directory, so you can use these
command files (almost) like builtin commands.
@node Commands, Variables, Command Interpretation, Interactive Interpreter
@section Commands
@menu
* AC::
* Alias::
* Alter::
* Asciiplot::
* Aspice::
* Bug::
* Cd::
* Destroy::
* DC::
* Define::
* Delete::
* Diff::
* Display::
* Echo::
* Edit::
* Fourier::
* Hardcopy::
* Help::
* History::
* Iplot::
* Jobs::
* Let::
* Linearize::
* Listing::
* Load::
* Op::
* Plot::
* Print::
* Quit::
* Rehash::
* Reset::
* Reshape::
* Resume::
* Rspice::
* Run::
* Rusage::
* Save::
* Sens::
* Set::
* Setcirc::
* Setplot::
* Settype::
* Shell::
* Shift::
* Show::
* Showmod::
* Source::
* Status::
* Step::
* Stop::
* Tf::
* Trace::
* Tran::
* Transpose::
* Unalias::
* Undefine::
* Unset::
* Version::
* Where::
* Write::
* Xgraph::
* While - End::
* Repeat - End::
* Dowhile - End::
* Foreach - End::
* If - Then - Else::
* Label::
* Goto::
* Continue::
* Break::
@end menu
@node AC, Alias, Commands, Commands
@subsection Ac*: Perform an AC, small-signal frequency response analysis
General Form:
@example
ac ( DEC | OCT | LIN ) N Fstart Fstop
@end example
Do an ac analysis. See the previous sections of this manual for more
details.
@node Alias, Alter, AC, Commands
@subsection Alias: Create an alias for a command
General Form:
@example
alias [word] [text ...]
@end example
Causes word to be aliased to text. History substitutions may be used,
as in C-shell aliases.
@node Alter, Asciiplot, Alias, Commands
@subsection Alter*: Change a device or model parameter
General Form:
@example
alter device value
alter device parameter value [ parameter value ]
@end example
Alter changes the value for a device or a specified parameter of a
device or model. The first form is used by simple devices which have
one principal value (resistors, capacitors, etc.) where the second form
is for more complex devices (bjt's, etc.). Model parameters can be
changed with the second form if the name contains a "#".
For specifying vectors as values, start the vector with "[", followed by
the values in the vector, and end with "]". Be sure to place a space
between each of the values and before and after the "[" and "]".
@node Asciiplot, Aspice, Alter, Commands
@subsection Asciiplot: Plot values using old-style character plots
General Form:
@example
asciiplot plotargs
@end example
Produce a line printer plot of the vectors. The plot is sent to the
standard output, so you can put it into a file with asciiplot args ... >
file. The set options width, height, and nobreak determine the width
and height of the plot, and whether there are page breaks, respectively.
Note that you will have problems if you try to asciiplot something with
an X-scale that isn't monotonic (i.e, something like sin(TIME) ),
because asciiplot uses a simple-minded linear interpolation.
@node Aspice, Bug, Asciiplot, Commands
@subsection Aspice: Asynchronous spice run
General Form:
@example
aspice input-file [output-file]
@end example
Start a SPICE-3 run, and when it is finished load the resulting data.
The raw data is kept in a temporary file. If output-file is specified
then the diagnostic output is directed into that file, otherwise it is
thrown away.
@node Bug, Cd, Aspice, Commands
@subsection Bug: Mail a bug report
General Form:
@example
bug
@end example
Send a bug report. Please include a short summary of the problem, the
version number and name of the operating system that you are running,
the version of Spice that you are running, and the relevant spice input
file. (If you have defined BUGADDR, the mail is delivered to there.)
@node Cd, Destroy, Bug, Commands
@subsection Cd: Change directory
General Form:
@example
cd [directory]
@end example
Change the current working directory to directory, or to the user's home
directory if none is given.
@node Destroy, DC, Cd, Commands
@subsection Destroy: Delete a data set
General Form:
@example
destroy [plotnames | all]
@end example
Release the memory holding the data for the specified runs.
@node DC, Define, Destroy, Commands
@subsection Dc*: Perform a DC-sweep analysis
General Form:
@example
dc Source-Name Vstart Vstop Vincr [ Source2 Vstart2 Vstop2 Vincr2 ]
@end example
Do a dc transfer curve analysis. See the previous sections of this
manual for more details.
@node Define, Delete, DC, Commands
@subsection Define: Define a function
General Form:
@example
define function(arg1, arg2, ...) expression
@end example
Define the user-definable function with the name function and arguments
arg1, arg2, ... to be expression, which may involve the arguments. When
the function is later used, the arguments it is given are substituted
for the formal arguments when it is parsed. If expression is not
present, any definition for function is printed, and if there are no
arguments to define then all currently active definitions are printed.
Note that you may have different functions defined with the same name
but different arities.
Some useful definitions are:
@example
define max(x,y) (x > y) * x + (x <= y) * y
define min(x,y) (x < y) * x + (x >= y) * y
@end example
@node Delete, Diff, Define, Commands
@subsection Delete*: Remove a trace or breakpoint
General Form:
@example
delete [ debug-number ... ]
@end example
Delete the specified breakpoints and traces. The debug numbers are
those shown by the status command (unless you do status > file, in which
case the debug numbers are not printed).
@node Diff, Display, Delete, Commands
@subsection Diff: Compare vectors
General Form:
@example
diff plot1 plot2 [vec ...]
@end example
Compare all the vectors in the specified plots, or only the named
vectors if any are given. There are different vectors in the two plots,
or any values in the vectors differ significantly the difference is
reported. The variable diff_abstol, diff_reltol, and diff_vntol are
used to determine a significant difference.
@node Display, Echo, Diff, Commands
@subsection Display: List known vectors and types
General Form:
@example
display [varname ...]
@end example
Prints a summary of currently defined vectors, or of the names
specified. The vectors are sorted by name unless the variable nosort is
set. The information given is the name of the vector, the length, the
type of the vector, and whether it is real or complex data.
Additionally, one vector is labeled [scale]. When a command such as
plot is given without a vs argument, this scale is used for the X-axis.
It is always the first vector in a rawfile, or the first vector defined
in a new plot. If you undefine the scale (i.e, let TIME = []), one of
the remaining vectors becomes the new scale (which is undetermined).
@node Echo, Edit, Display, Commands
@subsection Echo: Print text
General Form:
@example
echo [text...]
@end example
Echos the given text to the screen.
@node Edit, Fourier, Echo, Commands
@subsection Edit*: Edit the current circuit
General Form:
@example
edit [ file ]
@end example
Print the current Spice3 input file into a file, call up the editor on
that file and allow the user to modify it, and then read it back in,
replacing the original file. If a filename is given, then edit that
file and load it, making the circuit the current one.
@node Fourier, Hardcopy, Edit, Commands
@subsection Fourier: Perform a fourier transform
General Form:
@example
fourier fundamental_frequency [value ...]
@end example
Does a fourier analysis of each of the given values, using the first 10
multiples of the fundamental frequency (or the first nfreqs, if that
variable is set - see below). The output is like that of the .four
Spice3 line. The values may be any valid expression. The values are
interpolated onto a fixed-space grid with the number of points given by
the fourgridsize variable, or 200 if it is not set. The interpolation
is of degree polydegree if that variable is set, or 1. If polydegree is
0, then no interpolation is done. This is likely to give erroneous
results if the time scale is not monotonic, though.
@node Hardcopy, Help, Fourier, Commands
@subsection Hardcopy: Save a plot to a file for printing
General Form:
@example
hardcopy file plotargs
@end example
Just like plot, except creates a file called file containing the plot.
The file is an image in plot(5) format, and can be printed by either the
plot(1) program or lpr with the -g flag.
@node Help, History, Hardcopy, Commands
@subsection Help: Print summaries of Spice3 commands
General Form:
@example
help [all] [command ...]
@end example
Prints help. If the argument all is given, a short description of
everything you could possibly type is printed. If commands are given,
descriptions of those commands are printed. Otherwise help for only a
few major commands is printed.
@node History, Iplot, Help, Commands
@subsection History: Review previous commands
General Form:
@example
history [number]
@end example
Print out the history, or the last number commands typed at the
keyboard. Note: in Spice3 version 3a7 and earlier, all commands
(including ones read from files) were saved.
@node Iplot, Jobs, History, Commands
@subsection Iplot*: Incremental plot
General Form:
@example
iplot [ node ...]
@end example
Incrementally plot the values of the nodes while Spice3 runs. The iplot
command can be used with the where command to find trouble spots in a
transient simulation.
@node Jobs, Let, Iplot, Commands
@subsection Jobs: List active asynchronous spice runs
General Form:
@example
jobs
@end example
Report on the asynchronous SPICE-3 jobs currently running. Nutmeg
checks to see if the jobs are finished every time you execute a command.
If it is done then the data is loaded and becomes available.
@node Let, Linearize, Jobs, Commands
@subsection Let: Assign a value to a vector
General Form:
@example
let name = expr
@end example
Creates a new vector called name with the value specified by expr, an
expression as described above. If expr is [] (a zero-length vector)
then the vector becomes undefined. Individual elements of a vector may
be modified by appending a subscript to name (ex. name[0]). If there
are no arguments, let is the same as display.
@node Linearize, Listing, Let, Commands
@subsection Linearize*: Interpolate to a linear scale
General Form:
@example
linearize vec ...
@end example
Create a new plot with all of the vectors in the current plot, or only
those mentioned if arguments are given. The new vectors are
interpolated onto a linear time scale, which is determined by the values
of tstep, tstart, and tstop in the currently active transient analysis.
The currently loaded input file must include a transient analysis (a
tran command may be run interactively before the last reset,
alternately), and the current plot must be from this transient analysis.
This command is needed because Spice3 doesn't output the results from a
transient analysis in the same manner that Spice2 did.
@node Listing, Load, Linearize, Commands
@subsection Listing*: Print a listing of the current circuit
General Form:
@example
listing [logical] [physical] [deck] [expand]
@end example
If the logical argument is given, the listing is with all continuation
lines collapsed into one line, and if the physical argument is given the
lines are printed out as they were found in the file. The default is
logical. A deck listing is just like the physical listing, except
without the line numbers it recreates the input file verbatim (except
that it does not preserve case). If the word expand is present, the
circuit is printed with all subcircuits expanded.
@node Load, Op, Listing, Commands
@subsection Load: Load rawfile data
General Form:
@example
load [filename] ...
@end example
Loads either binary or ascii format rawfile data from the files named.
The default filename is rawspice.raw, or the argument to the -r flag if
there was one.
@node Op, Plot, Load, Commands
@subsection Op*: Perform an operating point analysis
General Form:
@example
op
@end example
Do an operating point analysis. See the previous sections of this
manual for more details.
@node Plot, Print, Op, Commands
@subsection Plot: Plot values on the display
General Form:
@example
plot exprs [ylimit ylo yhi] [xlimit xlo xhi] [xindices xilo xihi]
[xcompress comp] [xdelta xdel] [ydelta ydel] [xlog] [ylog] [loglog]
[vs xname] [xlabel word] [ylabel word] [title word] [samep]
[linear]
@end example
Plot the given exprs on the screen (if you are on a graphics terminal).
The xlimit and ylimit arguments determine the high and low x- and
y-limits of the axes, respectively. The xindices arguments determine
what range of points are to be plotted - everything between the xilo'th
point and the xihi'th point is plotted. The xcompress argument
specifies that only one out of every comp points should be plotted. If
an xdelta or a ydelta parameter is present, it specifies the spacing
between grid lines on the X- and Y-axis. These parameter names may be
abbreviated to xl, yl, xind, xcomp, xdel, and ydel respectively.
The xname argument is an expression to use as the scale on the
x-axis. If xlog or ylog are present then the X or Y scale, respectively,
is logarithmic (loglog is the same as specifying both). The xlabel and
ylabel arguments cause the specified labels to be used for the X and Y
axes, respectively.
If samep is given, the values of the other parameters (other than xname)
from the previous plot, hardcopy, or asciiplot command is used unless
re-defined on the command line.
The title argument is used in the place of the plot name at the bottom
of the graph.
The linear keyword is used to override a default logscale plot (as in
the output for an AC analysis).
Finally, the keyword polar to generate a polar plot. To produce a smith
plot, use the keyword smith. Note that the data is transformed, so for
smith plots you will see the data transformed by the function
(x-1)/(x+1). To produce a polar plot with a smith grid but without
performing the smith transform, use the keyword smithgrid.
@node Print, Quit, Plot, Commands
@subsection Print: Print values
General Form:
@example
print [col] [line] expr ...
@end example
Prints the vector described by the expression expr. If the col argument
is present, print the vectors named side by side. If line is given, the
vectors are printed horizontally. col is the default, unless all the
vectors named have a length of one, in which case line is the default.
The options width, length, and nobreak are effective for this command
(see asciiplot). If the expression is all, all of the vectors available
are printed. Thus print col all > file prints everything in the file in
SPICE2 format. The scale vector (time, frequency) is always in the
first column unless the variable noprintscale is true.
@node Quit, Rehash, Print, Commands
@subsection Quit: Leave Spice3 or Nutmeg
General Form:
@example
quit
@end example
Quit nutmeg or spice.
@node Rehash, Reset, Quit, Commands
@subsection Rehash: Reset internal hash tables
General Form:
@example
rehash
@end example
Recalculate the internal hash tables used when looking up UNIX commands,
and make all UNIX commands in the user's PATH available for command
completion. This is useless unless you have set unixcom first (see
above).
@node Reset, Reshape, Rehash, Commands
@subsection Reset*: Reset an analysis
General Form:
@example
reset
@end example
Throw out any intermediate data in the circuit (e.g, after a breakpoint
or after one or more analyses have been done already), and re-parse the
input file. The circuit can then be re-run from it's initial state,
overriding the affect of any set or alter commands. In Spice-3e and
earlier versions this was done automatically by the run command.
@node Reshape, Resume, Reset, Commands
@subsection Reshape: Alter the dimensionality or dimensions of
a vector
General Form:
@example
reshape vector vector ...
or
reshape vector vector ... [ dimension, dimension, ... ]
or
reshape vector vector ... [ dimension ][ dimension ] ...
@end example
This command changes the dimensions of a vector or a set of vectors.
The final dimension may be left off and it will be filled in
automatically. If no dimensions are specified, then the dimensions of
the first vector are copied to the other vectors. An error message of
the form 'dimensions of x were inconsistent' can be ignored.
@node Resume, Rspice, Reshape, Commands
@subsection Resume*: Continue a simulation after a stop
General Form:
@example
resume
@end example
Resume a simulation after a stop or interruption (control-C).
@node Rspice, Run, Resume, Commands
@subsection Rspice: Remote spice submission
General Form:
@example
rspice input file
@end example
Runs a SPICE-3 remotely taking the input file as a SPICE-3 input file,
or the current circuit if no argument is given. Nutmeg or Spice3 waits
for the job to complete, and passes output from the remote job to the
user's standard output. When the job is finished the data is loaded in
as with aspice. If the variable rhost is set, nutmeg connects to this
host instead of the default remote Spice3 server machine. This command
uses the "rsh" command and thereby requires authentication via a
".rhosts" file or other equivalent method. Note that "rsh" refers to
the "remote shell" program, which may be "remsh" on your system; to
override the default name of "rsh", set the variable remote_shell. If
the variable rprogram is set, then rspice uses this as the pathname to
the program to run on the remote system.
Note: rspice will not acknowledge elements that have been changed via
the "alter" or "altermod" commands.
@node Run, Rusage, Rspice, Commands
@subsection Run*: Run analysis from the input file
General Form:
@example
run [rawfile]
@end example
Run the simulation as specified in the input file. If there were any of
the control lines .ac, .op, .tran, or .dc, they are executed. The
output is put in rawfile if it was given, in addition to being available
interactively. In Spice-3e and earlier versions, the input file would
be re-read and any affects of the set or alter commands would be
reversed. This is no longer the affect.
@node Rusage, Save, Run, Commands
@subsection Rusage: Resource usage
General Form:
@example
rusage [resource ...]
@end example
Print resource usage statistics. If any resources are given, just print
the usage of that resource. Most resources require that a circuit be
loaded. Currently valid resources are:
elapsed The amount of time elapsed since the last rusage
elaped call.
faults Number of page faults and context switches (BSD only).
space Data space used.
time CPU time used so far.
temp Operating temperature.
tnom Temperature at which device parameters were measured.
equations Circuit Equations
time Total Analysis Time
totiter Total iterations
accept Accepted timepoints
rejected Rejected timepoints
loadtime Time spent loading the circuit matrix and RHS.
reordertime Matrix reordering time
lutime L-U decomposition time
solvetime Matrix solve time
trantime Transient analysis time
tranpoints Transient timepoints
traniter Transient iterations
trancuriters Transient iterations for the last time point*
tranlutime Transient L-U decomposition time
transolvetime Transient matrix solve time
everything All of the above.
* listed incorrectly as "Transient iterations per point".
@node Save, Sens, Rusage, Commands
@subsection Save*: Save a set of outputs
General Form:
@example
save [all | output ...]
.save [all | output ...]
@end example
Save a set of outputs, discarding the rest. If a node has been
mentioned in a save command, it appears in the working plot after a run
has completed, or in the rawfile if spice is run in batch mode. If a
node is traced or plotted (see below) it is also saved. For backward
compatibility, if there are no save commands given, all outputs are
saved.
When the keyword "all" appears in the save command, all default values
(node voltages and voltage source currents) are saved in addition to any
other values listed.
@node Sens, Set, Save, Commands
@subsection Sens*: Run a sensitivity analysis
General Form:
@example
sens output_variable
sens output_variable ac ( DEC | OCT | LIN ) N Fstart Fstop
@end example
Perform a Sensitivity analysis. output_variable is either a node
voltage (ex. "v(1)" or "v(A,out)") or a current through a voltage source
(ex. "i(vtest)"). The first form calculates DC sensitivities, the
second form calculates AC sensitivies. The output values are in
dimensions of change in output per unit change of input (as opposed to
percent change in output or per percent change of input).
@node Set, Setcirc, Sens, Commands
@subsection Set: Set the value of a variable
General Form:
@example
set [word]
set [word = value] ...
@end example
Set the value of word to be value, if it is present. You can set any
word to be any value, numeric or string. If no value is given then the
value is the boolean 'true'.
The value of word may be inserted into a command by writing $word. If a
variable is set to a list of values that are enclosed in parentheses
(which must be separated from their values by white space), the value of
the variable is the list.
The variables used by nutmeg are listed in the following section.
@node Setcirc, Setplot, Set, Commands
@subsection Setcirc*: Change the current circuit
General Form:
@example
setcirc [circuit name]
@end example
The current circuit is the one that is used for the simulation commands
below. When a circuit is loaded with the source command (see below) it
becomes the current circuit.
@node Setplot, Settype, Setcirc, Commands
@subsection Setplot: Switch the current set of vectors
General Form:
@example
setplot [plotname]
@end example
Set the current plot to the plot with the given name, or if no name is
given, prompt the user with a menu. (Note that the plots are named as
they are loaded, with names like tran1 or op2. These names are shown by
the setplot and display commands and are used by diff, below.) If the
"New plot" item is selected, the current plot becomes one with no
vectors defined.
Note that here the word "plot" refers to a group of vectors that are the
result of one SPICE run. When more than one file is loaded in, or more
than one plot is present in one file, nutmeg keeps them separate and
only shows you the vectors in the current plot.
@node Settype, Shell, Setplot, Commands
@subsection Settype: Set the type of a vector
General Form:
@example
settype type vector ...
@end example
Change the type of the named vectors to type. Type names can be found
in the manual page for sconvert.
@node Shell, Shift, Settype, Commands
@subsection Shell: Call the command interpreter
General Form:
@example
shell [ command ]
@end example
Call the operating system's command interpreter; execute the specified
command or call for interactive use.
@node Shift, Show, Shell, Commands
@subsection Shift: Alter a list variable
General Form:
@example
shift [varname] [number]
@end example
If varname is the name of a list variable, it is shifted to the left by
number elements (i.e, the number leftmost elements are removed). The
default varname is argv, and the default number is 1.
@node Show, Showmod, Shift, Commands
@subsection Show*: List device state
General Form:
@example
show devices [ : parameters ] , ...
@end example
The show command prints out tables summarizing the operating condition
of selected devices (much like the spice2 operation point summary). If
device is missing, a default set of devices are listed, if device is a
single letter, devices of that type are listed; if device is a
subcircuit name (beginning and ending in ":") only devices in that
subcircuit are shown (end the name in a double-":" to get devices within
sub-subcircuits recursively). The second and third forms may be
combined ("letter:subcircuit:") or "letter:subcircuit::") to select a
specific type of device from a subcircuit. A device's full name may be
specified to list only that device. Finally, devices may be selected by
model by using the form "#modelname" or ":subcircuit#modelname" or
"letter:subcircuit#modelname".
If no parameters are specified, the values for a standard set of
parameters are listed. If the list of parameters contains a "+", the
default set of parameters is listed along with any other specified
parameters.
For both devices and parameters, the word "all" has the obvious meaning.
Note: there must be spaces separating the ":" that divides the device
list from the parameter list.
@node Showmod, Source, Show, Commands
@subsection Showmod*: List model parameter values
General Form:
@example
showmod models [ : parameters ] , ...
@end example
The showmod command operates like the show command (above) but prints
out model parameter values. The applicable forms for models are a
single letter specifying the device type letter, "letter:subckt:",
"modelname", ":subckt:modelname", or "letter:subcircuit:modelname".
@node Source, Status, Showmod, Commands
@subsection Source: Read a Spice3 input file
General Form:
@example
source file
@end example
For Spice3: Read the Spice3 input file file. Nutmeg and Spice3 commands
may be included in the file, and must be enclosed between the lines
.control and .endc. These commands are executed immediately after the
circuit is loaded, so a control line of ac ... works the same as the
corresponding .ac card. The first line in any input file is considered
a title line and not parsed but kept as the name of the circuit. The
exception to this rule is the file .spiceinit. Thus, a Spice3 command
script must begin with a blank line and then with a acters *# is
considered a control line. This makes it possible to imbed commands in
Spice3 input files that are ignored by earlier versions of Spice2
For Nutmeg: Reads commands from the file filename. Lines beginning with
the character * are considered comments and ignored.
@node Status, Step, Source, Commands
@subsection Status*: Display breakpoint information
General Form:
@example
status
@end example
Display all of the traces and breakpoints currently in effect.
@node Step, Stop, Status, Commands
@subsection Step*: Run a fixed number of timepoints
General Form:
@example
step [number]
@end example
Iterate number times, or once, and then stop.
@node Stop, Tf, Step, Commands
@subsection Stop*: Set a breakpoint
General Form:
@example
stop [ after n] [ when value cond value ] ...
@end example
Set a breakpoint. The argument after n means stop after n iteration
number n, and the argument when value cond value means stop when the
first value is in the given relation with the second value, the possible
relations being
@example
eq or = equal to
ne or <> not equal to
gt or > greater than
lt or < less than
ge or >= greater than or equal to
le or <= less than or equal to
@end example
IO redirection is disabled for the stop command, since the relational
operations conflict with it (it doesn't produce any output anyway). The
values above may be node names in the running circuit, or real values.
If more than one condition is given, e.g. stop after 4 when @math{v(1) > 4}
when @math{v(2) < 2}, the conjunction of the conditions is implied.
@node Tf, Trace, Stop, Commands
@subsection Tf*: Run a Transfer Function analysis
General Form:
@example
tf output_node input_source
@end example
The tf command performs a transfer function analysis, returning the
transfer function (output/input), output resistance, and input
resistance between the given output node and the given input source.
The analysis assumes a small-signal DC (slowly varying) input.
@node Trace, Tran, Tf, Commands
@subsection Trace*: Trace nodes
General Form:
@example
trace [ node ...]
@end example
For every step of an analysis, the value of the node is printed.
Several traces may be active at once. Tracing is not applicable for all
analyses. To remove a trace, use the delete command.
@node Tran, Transpose, Trace, Commands
@subsection Tran*: Perform a transient analysis
General Form:
@example
tran Tstep Tstop [ Tstart [ Tmax ] ] [ UIC ]
@end example
Perform a transient analysis. See the previous sections of this manual
for more details.
@node Transpose, Unalias, Tran, Commands
@subsection Transpose: Swap the elements in a multi-dimensional data set
General Form:
@example
transpose vector vector ...
@end example
This command transposes a multidimensional vector. No analysis in
Spice3 produces multidimensional vectors, although the DC transfer curve
may be run with two varying sources. You must use the "reshape" command
to reform the one-dimensional vectors into two dimensional vectors. In
addition, the default scale is incorrect for plotting. You must plot
versus the vector corresponding to the second source, but you must also
refer only to the first segment of this second source vector. For
example (circuit to produce the tranfer characteristic of a MOS
transistor):
@example
spice3 > dc vgg 0 5 1 vdd 0 5 1
spice3 > plot i(vdd)
spice3 > reshape all [6,6]
spice3 > transpose i(vdd) v(drain)
spice3 > plot i(vdd) vs v(drain)[0]
@end example
@node Unalias, Undefine, Transpose, Commands
@subsection Unalias: Retract an alias
General Form:
@example
unalias [word ...]
@end example
Removes any aliases present for the words.
@node Undefine, Unset, Unalias, Commands
@subsection Undefine: Retract a definition
General Form:
@example
undefine function
@end example
Definitions for the named user-defined functions are deleted.
@node Unset, Version, Undefine, Commands
@subsection Unset: Clear a variable
General Form:
@example
unset [word ...]
@end example
Clear the value of the specified variable(s) (word).
@node Version, Where, Unset, Commands
@subsection Version: Print the version of Spice
General Form:
@example
version [version id]
@end example
Print out the version of nutmeg that is running. If there are
arguments, it checks to make sure that the arguments match the current
version of SPICE. (This is mainly used as a Command: line in rawfiles.)
@node Where, Write, Version, Commands
@subsection Where: Identify troublesome node or device
General Form:
@example
where
@end example
When performing a transient or operating point analysis, the name of the
last node or device to cause non-convergence is saved. The where
command prints out this information so that you can examine the circuit
and either correct the problem or make a bug report. You may do this
either in the middle of a run or after the simulator has given up on the
analysis. For transient simulation, the iplot command can be used to
monitor the progress of the analysis. When the analysis slows down
severly or hangs, interrupt the simulator (with control-C) and issue the
where command. Note that only one node or device is printed; there may
be problems with more than one node.
@node Write, Xgraph, Where, Commands
@subsection Write: Write data to a file
General Form:
@example
write [file] [exprs]
@end example
Writes out the expressions to file.
First vectors are grouped together by plots, and written out as such
(i.e, if the expression list contained three vectors from one plot and
two from another, then two plots are written, one with three vectors and
one with two). Additionally, if the scale for a vector isn't present,
it is automatically written out as well.
The default format is ascii, but this can be changed with the set
filetype command. The default filename is rawspice.raw, or the argument
to the -r flag on the command line, if there was one, and the default
expression list is all.
@node Xgraph, While - End, Write, Commands
@subsection Xgraph: use the xgraph(1) program for plotting.
General Form:
@example
xgraph file [exprs] [plot options]
@end example
The spice3/nutmeg xgraph command plots data like the plot command but
via xgraph, a popular X11 plotting program.
If file is either "temp" or "tmp" a temporary file is used to hold the
data while being plotted. For available plot options, see the plot
command. All options except for polar or smith plots are supported.
@section Control Structures
@node While - End, Repeat - End, Xgraph, Commands
@subsection While - End
General Form:
@example
while condition
statement
...
end
@end example
While condition, an arbitrary algebraic expression, is true, execute the
statements.
@node Repeat - End, Dowhile - End, While - End, Commands
@subsection Repeat - End
General Form:
@example
repeat [number]
statement
...
end
@end example
Execute the statements number times, or forever if no argument is given.
@node Dowhile - End, Foreach - End, Repeat - End, Commands
@subsection Dowhile - End
General Form:
@example
dowhile condition
statement
...
end
@end example
The same as while, except that the condition is tested after the
statements are executed.
@node Foreach - End, If - Then - Else, Dowhile - End, Commands
@subsection Foreach - End
General Form:
@example
foreach var value ...
statement
...
end
@end example
The statements are executed once for each of the values, each time with
the variable var set to the current one. (var can be accessed by the
$var notation - see below).
@node If - Then - Else, Label, Foreach - End, Commands
@subsection If - Then - Else
General Form:
@example
if condition
statement
...
else
statement
...
end
@end example
If the condition is non-zero then the first set of statements are
executed, otherwise the second set. The else and the second set of
statements may be omitted.
@node Label, Goto, If - Then - Else, Commands
@subsection Label
General Form:
@example
label word
@end example
If a statement of the form goto word is encountered, control is
transferred to this point, otherwise this is a no-op.
@node Goto, Continue, Label, Commands
@subsection Goto
General Form:
@example
goto word
@end example
If a statement of the form label word is present in the block or an
enclosing block, control is transferred there. Note that if the label
is at the top level, it must be before the goto statement (i.e, a
forward goto may occur only within a block).
@node Continue, Break, Goto, Commands
@subsection Continue
General Form:
@example
continue
@end example
If there is a while, dowhile, or foreach block enclosing this statement,
control passes to the test, or in the case of foreach, the next value is
taken. Otherwise an error results.
@node Break, , Continue, Commands
@subsection Break
General Form:
@example
break
@end example
If there is a while, dowhile, or foreach block enclosing this statement,
control passes out of the block. Otherwise an error results.
Of course, control structures may be nested. When a block is entered
and the input is the terminal, the prompt becomes a number of >'s
corresponding to the number of blocks the user has entered. The current
control structures may be examined with the debugging command cdump.
@node Variables, Bugs, Commands, Interactive Interpreter
@section Variables
The operation of both Nutmeg and Spice3 may be affected by setting
variables with the "set" command. In addition to the variables
mentioned below, the set command in Spice3 also affect the behaviour of
the simulator via the options previously described under the section on
".OPTIONS".
The variables meaningful to nutmeg which may be altered by the set
command are:
@vtable @code
@item diff_abstol
The absolute tolerance used by the diff command. appendwrite Append to
the file when a write command is is sued, if one already exists.
@item colorN
These variables determine the colors used, if X is being run on a color
display. N may be between 0 and 15. Color 0 is the background, color 1
is the grid and text color, and colors 2 through 15 are used in order
for vectors plot ted. The value of the color variables should be names
of colors, which may be found in the file /usr/lib/rgb.txt.
@item combplot
Plot vectors by drawing a vertical line from each point to the X-axis,
as opposed to joining the points. Note that this option is subsumed in
the plottype option, below.
@item cpdebug
Print cshpar debugging information (must be com plied with the -DCPDEBUG
flag). Unsupported in the current release.
@item debug
If set then a lot of debugging information is printed (must be compiled
with the -DFTEDEBUG flag). Unsupported in the current release.
@item device
The name (@code{/dev/tty??}) of the graphics device. If this variable
isn't set then the user's terminal is used. To do plotting on another
monitor you probably have to set both the device and term variables.
(If device is set to the name of a file, nutmeg dumps the graphics
control codes into this file -- this is useful for saving plots.)
@item echo
Print out each command before it is executed.
@item filetype
This can be either ascii or binary, and determines what format are. The
default is ascii.
@item fourgridsize
How many points to use for interpolating into when doing fourier
analysis.
@item gridsize
If this variable is set to an integer, this number is used as the number
of equally spaced points to use for the Y axis when plotting. Otherwise
the current scale is used (which may not have equally spaced points).
If the current scale isn't strictly monotonic, then this option has no
effect.
@item hcopydev
If this is set, when the hardcopy com mand is run the resulting file is
au tomatically printed on the printer named hcopydev with the command
@code{lpr -Phcopydev -g file}.
@item hcopyfont
This variable specifies the font name for hardcopy output plots. The
value is device dependent.
@item hcopyfontsize
This is a scaling factor for the font used in hardcopy plots.
@item hcopydevtype
This variable specifies the type of the printer output to use in the
hardcopy command. If hcopydevtype is not set, plot (5) format is
assumed. The stan dard distribution currently recognizes postscript as
an alternative output for mat. When used in conjunction with hcopydev,
hcopydevtype should specify a format supported by the printer.
@item height
The length of the page for asciiplot and print col.
@item history
The number of events to save in the his tory list.
@item lprplot5
This is a printf(3s) style format string used to specify the command to
use for sending plot(5)-style plots to a printer or plotter. The first
parameter sup plied is the printer name, the second parameter supplied
is a file name con taining the plot. Both parameters are strings. It
is trivial to cause Spice3 to abort by supplying a unreasonable format
string.
@item lprps
This is a printf(3s) style format string used to specify the command to
use for sending PostScript plots to a printer or plotter. The first
parameter supplied is the printer name, the second parame ter supplied
is a file name containing the plot. Both parameters are strings. It is
trivial to cause Spice3 to abort by supplying a unreasonable format
string.
@item nfreqs
The number of frequencies to compute in the fourier command. (Defaults
to 10.)
@item nobreak
Don't have asciiplot and print col break between pages.
@item noasciiplotvalue
Don't print the first vector plotted to the left when doing an
asciiplot.
@item noclobber
Don't overwrite existing files when do ing IO redirection.
@item noglob
Don't expand the global characters `*', `?', `[', and `]'. This is the
default.
@item nogrid
Don't plot a grid when graphing curves (but do label the axes).
@item nomoremode
If nomoremode is not set, whenever a large amount of data is being
printed to the screen (e.g, the print or asciiplot commands), the output
is stopped every screenful and continues when a carriage return is
typed. If nomoremode is set then data scrolls off the screen without
check.
@item nonomatch
If noglob is unset and a global expres sion cannot be matched, use the
global characters literally instead of com plaining.
@item nosort
Don't have display sort the variable names.
@item noprintscale
Don't print the scale in the leftmost column when a print col command is
given.
@item numdgt
The number of digits to print when printing tables of data (fourier,
print col). The default precision is 6 digits. On the VAX,
approximately 16 decimal digits are avail able using double precision,
so numdgt should not be more than 16. If the number is negative, one
fewer digit is printed to ensure constant widths in tables.
@item plottype
This should be one of normal, comb, or point:chars. normal, the
default, causes points to be plotted as parts of connected lines. comb
causes a comb plot to be done (see the description of the combplot vari
able above). point causes each point to be plotted separately - the
chars are a list of characters that are used for each vector plotted.
If they are omitted then a de fault set is used.
@item polydegree
The degree of the polynomial that the plot command should fit to the
data. If polyde gree is N, then nutmeg fits a degree N po lynomial to
every set of N points and draw 10 intermediate points in between each
end point. If the points aren't monotonic, then it tries rotating the
curve and reduc ing the degree until a fit is achieved.
@item polysteps
The number of points to interpolate between every pair of points
available when doing curve fitting. The default is 10.
@item program
The name of the current program (argv[0]).
@item prompt
The prompt, with the character `!' replaced by the current event number.
@item rawfile
The default name for rawfiles created.
@item diff_reltol
The relative tolerance used by the diff command.
@item remote_shell
Overrides the name used for generating rspice runs (default is
"rsh").
@item rhost
The machine to use for remote SPICE-3 runs, in stead of the default one
(see the description of the rspice command, below).
@item rprogram
The name of the remote program to use in the rspice command.
@item slowplot
Stop between each graph plotted and wait for the user to type return
before continuing.
@item sourcepath
A list of the directories to search when a source command is given. The
default is the current directory and the standard spice library
(/usr/local/lib/spice, or whatever LIBPATH is #defined to in the Spice3
source.
@item spicepath
The program to use for the aspice command. The default is
/cad/bin/spice.
@item term
The mfb name of the current terminal.
@item units
If this is degrees, then all the trig functions will use degrees instead
of radians.
@item unixcom
If a command isn't defined, try to execute it as a UNIX command.
Setting this option has the ef fect of giving a rehash command, below.
This is useful for people who want to use nutmeg as a login shell.
@item verbose
Be verbose. This is midway between echo and de bug / cpdebug.
@item diff _vntol
The absolute voltage tolerance used by the diff command.
@item width
The width of the page for asciiplot and print col.
@item x11lineararcs
Some X11 implementations have poor arc drawing. If you set this option,
Spice3 will plot using an approximation to the curve using straight
lines.
@item xbrushheight
The height of the brush to use if X is being run.
@item xbrushwidth
The width of the brush to use if X is being run.
@item xfont
The name of the X font to use when plot ting data and entering labels.
The plot may not look good if this is a variable-width font.
@end vtable
There are several set variables that Spice3 uses but Nutmeg does
not. They are:
@vtable @code
@item editor
The editor to use for the edit command.
@item modelcard
The name of the model card (normally
@item noaskquit
Do not check to make sure that there are no circuits suspended and no
plots un saved. Normally Spice3 warns the user when he tries to quit if
this is the case.
@item nobjthack
Assume that BJTs have 4 nodes.
@item noparse
Don't attempt to parse input files when they are read in (useful for
debugging). Of course, they cannot be run if they are not parsed.
nosubckt Don't expand subcircuits.
@item renumber
Renumber input lines when an input file has .include's. subend The card
to end subcircuits (normally
@item subinvoke
The prefix to invoke subcircuits (nor mally x). substart The card to
begin subcircuits (normally
@end vtable
@section MISCELLANEOUS
If there are subcircuits in the input file, Spice3 expands instances of
them. A subcircuit is delimited by the cards .subckt and .ends, or
whatever the value of the variables substart and subend is,
respectively. An instance of a subcircuit is created by specifying a
device with type 'x' - the device line is written
@example
xname node1 node2 ... subcktname
@end example
where the nodes are the node names that replace the formal parameters on
the .subckt line. All nodes that are not formal parameters are
prepended with the name given to the instance and a ':', as are the
names of the devices in the subcircuit. If there are several nested
subcircuits, node and device names look like subckt1:subckt2:...:name.
If the variable subinvoke is set, then it is used as the prefix that
specifies instances of subcircuits, instead of 'x'.
Nutmeg occasionally checks to see if it is getting close to running out
of space, and warns the user if this is the case. (This is more likely
to be useful with the SPICE front end.)
C-shell type quoting with "" and '', and backquote substitution may be
used. Within single quotes, no further substitution (like history
substitution) is done, and within double quotes, the words are kept
together but further substitution is done. Any text between backquotes
is replaced by the result of executing the text as a command to the
shell.
Tenex-style ('set filec' in the 4.3 C-shell) command, filename, and
keyword completion is possible: If EOF (control-D) is typed after the
first character on the line, a list of the commands or possible
arguments is printed (If it is alone on the line it exits nutmeg). If
escape is typed, then nutmeg trys to complete what the user has already
typed. To get a list of all commands, the user should type <space> ^D.
The values of variables may be used in commands by writing $varname
where the value of the variable is to appear. The special variables $$
and $< refer to the process ID of the program and a line of input which
is read from the terminal when the variable is evaluated, respectively.
If a variable has a name of the form $&word, then word is considered a
vector (see above), and its value is taken to be the value of the
variable. If $foo is a valid variable, and is of type list, then the
expression $foo[low-high] represents a range of elements. Either the
upper index or the lower may be left out, and the reverse of a list may
be obtained with $foo[len-0]. Also, the notation $?foo evaluates to 1
if the variable foo is defined, 0 otherwise, and $#foo evaluates to the
number of elements in foo if it is a list, 1 if it is a number or
string, and 0 if it is a boolean variable.
History substitutions, similar to C-shell history substitutions, are
also available - see the C-shell manual page for all of the details.
The characters ~, @{, and @} have the same effects as they do in the
C-Shell, i.e., home directory and alternative expansion. It is possible
to use the wildcard characters *, ?, [, and ] also, but only if you
unset noglob first. This makes them rather useless for typing algebraic
expressions, so you should set noglob again after you are done with
wildcard expansion. Note that the pattern [^abc] matchs all characters
except a, b, and c.
IO redirection is available - the symbols >, >>, >&, >>&, and < have the
same effects as in the C-shell.
You may type multiple commands on one line, separated by semicolons.
If you want to use a different mfbcap file than the default (usually
~cad/lib/mfbcap), you have to set the environment variable SPICE_MFBCAP
before you start nutmeg or spice. The -m option and the mfbcap variable
no longer work.
If X is being used, the cursor may be positioned at any point on the
screen when the window is up and characters typed at the keyboard are
added to the window at that point. The window may then be sent to a
printer using the xpr(1) program.
Nutmeg can be run under VAX/VMS, as well as several other operating
systems. Some features like command completion, expansion of *, ?, and
[], backquote substitution, the shell command, and so forth do not work.
On some systems you have to respond to the -moreprompt during plot with
a carriage return instead of any key as you can do on UNIX.
@node Bugs, , Variables, Interactive Interpreter
@section Bugs
The label entry facilities are primitive. You must be careful to type
slowly when entering labels -- nutmeg checks for input once every
second, and can get confused if characters arrive faster.
If you redefine colors after creating a plot window with X, and then
cause the window to be redrawn, it does not redraw in the correct
colors.
When defining aliases like
@example
alias pdb plot db( '!:1' - '!:2' )
@end example
you must be careful to quote the argument list substitutions in this
manner. If you quote the whole argument it might not work properly.
In a user-defined function, the arguments cannot be part of a name that
uses the plot.vec syntax. For example:
@example
define check(v(1)) cos(tran1.v(1))
@end example
does not work.
If you type plot all all, or otherwise use a wildcard reference for one
plot twice in a command, the effect is unpredictable.
The asciiplot command doesn't deal with log scales or the delta
keywords.
Often the names of terminals recognized by MFB are different from those
in /etc/termcap. Thus you may have to reset your terminal type with the
command
@example
set term = termname
@end example
where termname is the name in the mfbcap file.
The hardcopy command is useless on VMS and other systems without the
plot command, unless the user has a program that understands plot(5)
format.
Spice3 recognizes all the notations used in SPICE2 .plot cards, and
translates vp(1) into ph(v(1)), and so forth. However, if there are
spaces in these names it won't work. Hence v(1, 2) and (-.5, .5) aren't
recognized.
BJTs can have either 3 or 4 nodes, which makes it difficult for the
subcircuit expansion routines to decide what to rename. If the fourth
parameter has been declared as a model name, then it is assumed that
there are 3 nodes, otherwise it is considered a node. To disable this,
you can set the variable "nobjthack" which forces BJTs to have 4 nodes
(for the purposes of subcircuit expansion, at least).
The @@name[param] notation might not work with trace, iplot, etc. yet.
The first line of a command file (except for the .spiceinit file) should
be a comment, otherwise SPICE may create an empty circuit.
Files specified on the command line are read before .spiceinit is read.
@node Bibliography, Example Circuits, Interactive Interpreter, Top
@chapter Bibliography
[1] A. Vladimirescu and S. Liu, The Simulation of MOS Integrated
Circuits Using SPICE2 ERL Memo No. ERL M80/7, Electronics Research
Laboratory University of California, Berkeley, October 1980
[2] T. Sakurai and A. R. Newton, A Simple MOSFET Model for Circuit
Analysis and its application to CMOS gate delay analysis and
series-connected MOSFET Structure ERL Memo No. ERL M90/19, Electronics
Research Labora tory, University of California, Berkeley, March 1990
[3] B. J. Sheu, D. L. Scharfetter, and P. K. Ko, SPICE2
Implementation of BSIM ERL Memo No. ERL M85/42, Electronics Research
Labora tory University of California, Berkeley, May 1985
[4] J. R. Pierret, A MOS Parameter Extraction Program for the BSIM
Model ERL Memo Nos. ERL M84/99 and M84/100, Electronics Research
Laboratory University of California, Berkeley, November 1984
[5] Min-Chie Jeng, Design and Modeling of Deep Submicrometer MOSFETSs
ERL Memo Nos. ERL M90/90, Electronics Research Labora tory University of
California, Berkeley, October 1990
[6] Soyeon Park, Analysis and SPICE implementation of High Temperature
Effects on MOSFET, Master's thesis, University of California, Berkeley,
December 1986.
[7] Clement Szeto, Simulator of Temperature Effects in MOS FETs
(STEIM), Master's thesis, University of California, Berkeley, May 1988.
[8] J.S. Roychowdhury and D.O. Pederson, Efficient Tran sient
Simulation of Lossy Interconnect, Proc. of the 28th ACM/IEEE Design
Automation Confer ence, June 17-21 1991, San Francisco
[9] A. E. Parker and D. J. Skellern, An Improved FET Model for Computer
Simulators, IEEE Trans CAD, vol. 9, no. 5, pp. 551-553, May 1990.
[10] R. Saleh and A. Yang, Editors, Simulation and Modeling, IEEE
Circuits and Devices, vol. 8, no. 3, pp. 7-8 and 49, May 1992
[11] H.Statz et al., GaAs FET Device and Circuit Simulation in SPICE,
IEEE Transactions on Electron Devices, V34, Number 2, February, 1987
pp160-169.
@node Example Circuits, Model and Device Parameters, Bibliography, Top
@chapter Example Circuits
@menu
* Differential Pair::
* MOSFET Characterization::
* RTL Inverter::
* Four-Bit Binary Adder::
* Transmission-Line Inverter::
@end menu
@node Differential Pair, MOSFET Characterization, Example Circuits, Example Circuits
@section Differential Pair
The following deck determines the dc operating point of a simple
differential pair. In addition, the ac small-signal response is computed
over the frequency range 1Hz to 100MEGHz.
@example
SIMPLE DIFFERENTIAL PAIR
VCC 7 0 12
VEE 8 0 -12
VIN 1 0 AC 1
RS1 1 2 1K
RS2 6 0 1K
Q1 3 2 4 MOD1
Q2 5 6 4 MOD1
RC1 7 3 10K
RC2 7 5 10K
RE 4 8 10K
.MODEL MOD1 NPN BF=50 VAF=50 IS=1.E-12 RB=100 CJC=.5PF TF=.6NS
.TF V(5) VIN
.AC DEC 10 1 100MEG
.END
@end example
@node MOSFET Characterization, RTL Inverter, Differential Pair, Example Circuits
@section MOSFET Characterization
The following deck computes the output characteristics of a MOSFET
device over the range 0-10V for VDS and 0-5V for VGS.
@example
MOS OUTPUT CHARACTERISTICS
.OPTIONS NODE NOPAGE
VDS 3 0
VGS 2 0
M1 1 2 0 0 MOD1 L=4U W=6U AD=10P AS=10P
* VIDS MEASURES ID, WE COULD HAVE USED VDS, BUT ID WOULD BE NEGATIVE
VIDS 3 1
.MODEL MOD1 NMOS VTO=-2 NSUB=1.0E15 UO=550
.DC VDS 0 10 .5 VGS 0 5 1
.END
@end example
@node RTL Inverter, Four-Bit Binary Adder, MOSFET Characterization, Example Circuits
@section RTL Inverter
The following deck determines the dc transfer curve and the transient
pulse response of a simple RTL inverter. The input is a pulse from 0 to
5 Volts with delay, rise, and fall times of 2ns and a pulse width of
30ns. The transient interval is 0 to 100ns, with printing to be done
every nanosecond.
@example
SIMPLE RTL INVERTER
VCC 4 0 5
VIN 1 0 PULSE 0 5 2NS 2NS 2NS 30NS
RB 1 2 10K
Q1 3 2 0 Q1
RC 3 4 1K
.MODEL Q1 NPN BF 20 RB 100 TF .1NS CJC 2PF
.DC VIN 0 5 0.1
.TRAN 1NS 100NS
.END
@end example
@node Four-Bit Binary Adder, Transmission-Line Inverter, RTL Inverter, Example Circuits
@section Four-Bit Binary Adder
The following deck simulates a four-bit binary adder, using several
subcircuits to describe various pieces of the overall circuit.
@example
ADDER - 4 BIT ALL-NAND-GATE BINARY ADDER
*** SUBCIRCUIT DEFINITIONS
.SUBCKT NAND 1 2 3 4
* NODES: INPUT(2), OUTPUT, VCC
Q1 9 5 1 QMOD
D1CLAMP 0 1 DMOD
Q2 9 5 2 QMOD
D2CLAMP 0 2 DMOD
RB 4 5 4K
R1 4 6 1.6K
Q3 6 9 8 QMOD
R2 8 0 1K
RC 4 7 130
Q4 7 6 10 QMOD
DVBEDROP 10 3 DMOD
Q5 3 8 0 QMOD
.ENDS NAND
.SUBCKT ONEBIT 1 2 3 4 5 6
* NODES: INPUT(2), CARRY-IN, OUTPUT, CARRY-OUT, VCC
X1 1 2 7 6 NAND
X2 1 7 8 6 NAND
X3 2 7 9 6 NAND
X4 8 9 10 6 NAND
X5 3 10 11 6 NAND
X6 3 11 12 6 NAND
X7 10 11 13 6 NAND
X8 12 13 4 6 NAND
X9 11 7 5 6 NAND
.ENDS ONEBIT
.SUBCKT TWOBIT 1 2 3 4 5 6 7 8 9
* NODES: INPUT - BIT0(2) / BIT1(2), OUTPUT - BIT0 / BIT1,
* CARRY-IN, CARRY-OUT, VCC
X1 1 2 7 5 10 9 ONEBIT
X2 3 4 10 6 8 9 ONEBIT
.ENDS TWOBIT
.SUBCKT FOURBIT 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15
* NODES: INPUT - BIT0(2) / BIT1(2) / BIT2(2) / BIT3(2),
* OUTPUT - BIT0 / BIT1 / BIT2 / BIT3, CARRY-IN, CARRY-OUT, VCC
X1 1 2 3 4 9 10 13 16 15 TWOBIT
X2 5 6 7 8 11 12 16 14 15 TWOBIT
.ENDS FOURBIT
*** DEFINE NOMINAL CIRCUIT
.MODEL DMOD D
.MODEL QMOD NPN(BF=75 RB=100 CJE=1PF CJC=3PF)
VCC 99 0 DC 5V
VIN1A 1 0 PULSE(0 3 0 10NS 10NS 10NS 50NS)
VIN1B 2 0 PULSE(0 3 0 10NS 10NS 20NS 100NS)
VIN2A 3 0 PULSE(0 3 0 10NS 10NS 40NS 200NS)
VIN2B 4 0 PULSE(0 3 0 10NS 10NS 80NS 400NS)
VIN3A 5 0 PULSE(0 3 0 10NS 10NS 160NS 800NS)
VIN3B 6 0 PULSE(0 3 0 10NS 10NS 320NS 1600NS)
VIN4A 7 0 PULSE(0 3 0 10NS 10NS 640NS 3200NS)
VIN4B 8 0 PULSE(0 3 0 10NS 10NS 1280NS 6400NS)
X1 1 2 3 4 5 6 7 8 9 10 11 12 0 13 99 FOURBIT
RBIT0 9 0 1K
RBIT1 10 0 1K
RBIT2 11 0 1K
RBIT3 12 0 1K
RCOUT 13 0 1K
*** (FOR THOSE WITH MONEY (AND MEMORY) TO BURN)
.TRAN 1NS 6400NS
.END
@end example
@node Transmission-Line Inverter, , Four-Bit Binary Adder, Example Circuits
@section Transmission-Line Inverter
The following deck simulates a transmission-line inverter. Two
transmission-line elements are required since two propagation modes are
excited. In the case of a coaxial line, the first line (T1) models the
inner conductor with respect to the shield, and the second line (T2)
models the shield with respect to the outside world.
@example
TRANSMISSION-LINE INVERTER
V1 1 0 PULSE(0 1 0 0.1N)
R1 1 2 50
X1 2 0 0 4 TLINE
R2 4 0 50
.SUBCKT TLINE 1 2 3 4
T1 1 2 3 4 Z0=50 TD=1.5NS
T2 2 0 4 0 Z0=100 TD=1NS
.ENDS TLINE
.TRAN 0.1NS 20NS
.END
@end example
@node Model and Device Parameters, , Example Circuits, Top
@chapter Model and Device Parameters
The following tables summarize the parameters available on each of the
devices and models in (note that for some systems with limited memory,
output parameters are not available). There are several tables for each
type of device supported by . Input parameters to instances and models
are parameters that can occur on an instance or model definition line in
the form "keyword=value" where "keyword" is the parameter name as given
in the tables. Default input parameters (such as the resistance of a
resistor or the capacitance of a capacitor) obviously do not need the
keyword specified.
Output parameters are those additional parameters which are available
for many types of instances for the output of operating point and
debugging information. These parameters are specified as
"@@device[keyword]" and are available for the most recent point computed
or, if specified in a ".save" statement, for an entire simulation as a
normal output vector. Thus, to monitor the gate-to-source capacitance
of a MOSFET, a command
@example
save @@m1[cgs]
@end example
given before a transient simulation causes the specified capacitance
value to be saved at each timepoint, and a subsequent command such as
@example
plot @@m1[cgs]
@end example
produces the desired plot. (Note that the show command does not use
this format).
Some variables are listed as both input and output, and their output
simply returns the previously input value, or the default value after
the simulation has been run. Some parameter are input only because the
output system can not handle variables of the given type yet, or the
need for them as output variables has not been apparent. Many such
input variables are available as output variables in a different format,
such as the initial condition vectors that can be retrieved as
individual initial condition values. Finally, internally derived values
are output only and are provided for debugging and operating point
output purposes.
Please note that these tables do not provide the detailed information
available about the parameters provided in the section on each device
and model, but are provided as a quick reference guide.
@menu
* Uniform RC line::
* Arbitrary Source::
* Bipolar Junction Transistor::
* BSIM1 Berkeley Short Channel IGFET Model::
* BSIM2 Berkeley Short Channel IGFET Model::
* Fixed capacitor::
* Current controlled current source::
* Linear current controlled current source::
* Current controlled ideal switch::
* Junction Diode model::
* Inductor::
* Mutual inductors::
* Independent current source::
* Junction Field effect transistor::
* Lossy transmission line::
* GaAs MESFET model::
* Level 1 MOSfet model::
* Level 2 MOSfet model::
* Level 3 MOSfet model::
* Level 6 MOSfet model::
* Simple linear resistor::
* Ideal voltage controlled switch::
* Lossless transmission line::
* Voltage controlled current source::
* Voltage controlled voltage source::
* Independent voltage source::
@end menu
@node Uniform RC line, Arbitrary Source, Model and Device Parameters, Model and Device Parameters
@section URC: Uniform R.C. line
------------------------------------------------------------
| URC - instance parameters (input-output) |
|-----------------------------------------------------------+
| l Length of transmission line |
| n Number of lumps |
------------------------------------------------------------
------------------------------------------------------------
| URC - instance parameters (output-only) |
|-----------------------------------------------------------+
| pos_node Positive node of URC |
| neg_node Negative node of URC |
| gnd Ground node of URC |
------------------------------------------------------------
------------------------------------------------------------
| URC - model parameters (input-only) |
|-----------------------------------------------------------+
| urc Uniform R.C. line model |
------------------------------------------------------------
------------------------------------------------------------
| URC - model parameters (input-output) |
|-----------------------------------------------------------+
| k Propagation constant |
| fmax Maximum frequency of interest |
| rperl Resistance per unit length |
| cperl Capacitance per unit length |
| isperl Saturation current per length |
| rsperl Diode resistance per length |
------------------------------------------------------------
@node Arbitrary Source, Bipolar Junction Transistor, Uniform RC line, Model and Device Parameters
@section ASRC: Arbitrary Source
------------------------------------------------------------
| ASRC - instance parameters (input-only) |
|-----------------------------------------------------------+
| i Current source |
| v Voltage source |
------------------------------------------------------------
------------------------------------------------------------
| ASRC - instance parameters (output-only) |
|-----------------------------------------------------------+
| i Current through source |
| v Voltage across source |
| pos_node Positive Node |
| neg_node Negative Node |
------------------------------------------------------------
@node Bipolar Junction Transistor, BSIM1 Berkeley Short Channel IGFET Model, Arbitrary Source, Model and Device Parameters
@section BJT: Bipolar Junction Transistor
------------------------------------------------------------
| BJT - instance parameters (input-only) |
|-----------------------------------------------------------+
| ic Initial condition vector |
------------------------------------------------------------
------------------------------------------------------------
| BJT - instance parameters (input-output) |
|-----------------------------------------------------------+
| off Device initially off |
| icvbe Initial B-E voltage |
| icvce Initial C-E voltage |
| area Area factor |
| temp instance temperature |
------------------------------------------------------------
------------------------------------------------------------
| BJT - instance parameters (output-only) |
|-----------------------------------------------------------+
| colnode Number of collector node |
| basenode Number of base node |
| emitnode Number of emitter node |
| substnode Number of substrate node |
------------------------------------------------------------
| colprimenode Internal collector node |
| baseprimenode Internal base node |
| emitprimenode Internal emitter node |
| ic Current at collector node |
|-----------------------------------------------------------+
ib Current at base node
| ie Emitter current |
| is Substrate current |
| vbe B-E voltage |
------------------------------------------------------------
| vbc B-C voltage |
| gm Small signal transconductance |
| gpi Small signal input conductance - pi |
| gmu Small signal conductance - mu |
|-----------------------------------------------------------+
| gx Conductance from base to internal base |
| go Small signal output conductance |
| geqcb d(Ibe)/d(Vbc) |
| gccs Internal C-S cap. equiv. cond. |
------------------------------------------------------------
| geqbx Internal C-B-base cap. equiv. cond. |
| cpi Internal base to emitter capactance |
| cmu Internal base to collector capactiance |
| cbx Base to collector capacitance |
|-----------------------------------------------------------+
| ccs Collector to substrate capacitance |
| cqbe Cap. due to charge storage in B-E jct. |
| cqbc Cap. due to charge storage in B-C jct. |
| cqcs Cap. due to charge storage in C-S jct. |
| cqbx Cap. due to charge storage in B-X jct. |
| continued |
------------------------------------------------------------
------------------------------------------------------------
| BJT - instance output-only parameters - continued
|-----------------------------------------------------------+
| cexbc Total Capacitance in B-X junction |
| qbe Charge storage B-E junction |
| qbc Charge storage B-C junction |
| qcs Charge storage C-S junction |
| qbx Charge storage B-X junction |
| p Power dissipation |
------------------------------------------------------------
------------------------------------------------------------
| BJT - model parameters (input-output) |
|-----------------------------------------------------------+
| npn NPN type device |
| pnp PNP type device |
| is Saturation Current |
| bf Ideal forward beta |
------------------------------------------------------------
| nf Forward emission coefficient |
| vaf Forward Early voltage |
| va (null) |
| ikf Forward beta roll-off corner current |
|-----------------------------------------------------------+
| ik (null) |
| ise B-E leakage saturation current |
| ne B-E leakage emission coefficient |
| br Ideal reverse beta |
------------------------------------------------------------
| nr Reverse emission coefficient |
| var Reverse Early voltage |
| vb (null) |
| ikr reverse beta roll-off corner current |
|-----------------------------------------------------------+
| isc B-C leakage saturation current |
| nc B-C leakage emission coefficient |
| rb Zero bias base resistance |
| irb Current for base resistance=(rb+rbm)/2 |
------------------------------------------------------------
| rbm Minimum base resistance |
| re Emitter resistance |
| rc Collector resistance |
| cje Zero bias B-E depletion capacitance |
|-----------------------------------------------------------+
| vje B-E built in potential |
| pe (null) |
| mje B-E junction grading coefficient |
| me (null) |
------------------------------------------------------------
| tf Ideal forward transit time |
| xtf Coefficient for bias dependence of TF |
| vtf Voltage giving VBC dependence of TF |
| itf High current dependence of TF |
|-----------------------------------------------------------+
| ptf Excess phase |
| cjc Zero bias B-C depletion capacitance |
| vjc B-C built in potential |
| continued |
------------------------------------------------------------
------------------------------------------------------------
| BJT - model input-output parameters - continued
|-----------------------------------------------------------+
| pc (null) |
| mjc B-C junction grading coefficient |
| mc (null) |
| xcjc Fraction of B-C cap to internal base |
------------------------------------------------------------
| tr Ideal reverse transit time |
| cjs Zero bias C-S capacitance |
| ccs Zero bias C-S capacitance |
| vjs Substrate junction built in potential |
|-----------------------------------------------------------+
| ps (null) |
| mjs Substrate junction grading coefficient |
| ms (null) |
| xtb Forward and reverse beta temp. exp. |
------------------------------------------------------------
| eg Energy gap for IS temp. dependency |
| xti Temp. exponent for IS |
| fc Forward bias junction fit parameter |
| tnom Parameter measurement temperature |
| kf Flicker Noise Coefficient |
| af Flicker Noise Exponent |
------------------------------------------------------------
------------------------------------------------------------
| BJT - model parameters (output-only) |
|-----------------------------------------------------------+
| type NPN or PNP |
| invearlyvoltf Inverse early voltage:forward |
| invearlyvoltr Inverse early voltage:reverse |
| invrollofff Inverse roll off - forward |
------------------------------------------------------------
| invrolloffr Inverse roll off - reverse |
| collectorconduct Collector conductance |
| emitterconduct Emitter conductance |
| transtimevbcfact Transit time VBC factor |
| excessphasefactor Excess phase fact. |
------------------------------------------------------------
@node BSIM1 Berkeley Short Channel IGFET Model, BSIM2 Berkeley Short Channel IGFET Model, Bipolar Junction Transistor, Model and Device Parameters
@section BSIM1: Berkeley Short Channel IGFET Model
------------------------------------------------------------
| BSIM1 - instance parameters (input-only) |
|-----------------------------------------------------------+
| ic Vector of DS,GS,BS initial voltages |
------------------------------------------------------------
------------------------------------------------------------
| BSIM1 - instance parameters (input-output) |
|-----------------------------------------------------------+
| l Length |
| w Width |
| ad Drain area |
| as Source area |
------------------------------------------------------------
| pd Drain perimeter |
| ps Source perimeter |
| nrd Number of squares in drain |
| nrs Number of squares in source |
|-----------------------------------------------------------+
| off Device is initially off |
| vds Initial D-S voltage |
| vgs Initial G-S voltage |
| vbs Initial B-S voltage |
------------------------------------------------------------
------------------------------------------------------------
| BSIM1 - model parameters (input-only) |
|-----------------------------------------------------------+
| nmos Flag to indicate NMOS |
| pmos Flag to indicate PMOS |
------------------------------------------------------------
------------------------------------------------------------
| BSIM1 - model parameters (input-output) |
|-----------------------------------------------------------+
| vfb Flat band voltage |
lvfb Length dependence of vfb
| wvfb Width dependence of vfb |
| phi Strong inversion surface potential |
------------------------------------------------------------
| lphi Length dependence of phi |
| wphi Width dependence of phi |
| k1 Bulk effect coefficient 1 |
| lk1 Length dependence of k1 |
|-----------------------------------------------------------+
| wk1 Width dependence of k1 |
| k2 Bulk effect coefficient 2 |
| lk2 Length dependence of k2 |
| wk2 Width dependence of k2 |
------------------------------------------------------------
| eta VDS dependence of threshold voltage |
| leta Length dependence of eta |
| weta Width dependence of eta |
| x2e VBS dependence of eta |
| lx2e Length dependence of x2e |
| continued |
------------------------------------------------------------
---------------------------------------------------------------------
| BSIM1 - model input-output parameters - continued|
|--------------------------------------------------------------------+
|wx2e Width dependence of x2e |
|x3e VDS dependence of eta |
|lx3e Length dependence of x3e |
|wx3e Width dependence of x3e |
---------------------------------------------------------------------
|dl Channel length reduction in um |
|dw Channel width reduction in um |
|muz Zero field mobility at VDS=0 VGS=VTH |
|x2mz VBS dependence of muz |
|--------------------------------------------------------------------+
|lx2mz Length dependence of x2mz |
|wx2mz Width dependence of x2mz |
mus Mobility at VDS=VDD VGS=VTH, channel length modulation
|lmus Length dependence of mus |
---------------------------------------------------------------------
|wmus Width dependence of mus |
|x2ms VBS dependence of mus |
|lx2ms Length dependence of x2ms |
|wx2ms Width dependence of x2ms |
|--------------------------------------------------------------------+
|x3ms VDS dependence of mus |
|lx3ms Length dependence of x3ms |
|wx3ms Width dependence of x3ms |
|u0 VGS dependence of mobility |
---------------------------------------------------------------------
|lu0 Length dependence of u0 |
|wu0 Width dependence of u0 |
|x2u0 VBS dependence of u0 |
|lx2u0 Length dependence of x2u0 |
|--------------------------------------------------------------------+
|wx2u0 Width dependence of x2u0 |
|u1 VDS depence of mobility, velocity saturation |
|lu1 Length dependence of u1 |
|wu1 Width dependence of u1 |
---------------------------------------------------------------------
|x2u1 VBS depence of u1 |
|lx2u1 Length depence of x2u1 |
|wx2u1 Width depence of x2u1 |
|x3u1 VDS depence of u1 |
|--------------------------------------------------------------------+
|lx3u1 Length dependence of x3u1 |
|wx3u1 Width depence of x3u1 |
|n0 Subthreshold slope |
ln0 Length dependence of n0
---------------------------------------------------------------------
|wn0 Width dependence of n0 |
|nb VBS dependence of subthreshold slope |
|lnb Length dependence of nb |
|wnb Width dependence of nb |
|--------------------------------------------------------------------+
|nd VDS dependence of subthreshold slope |
|lnd Length dependence of nd |
|wnd Width dependence of nd |
| continued |
---------------------------------------------------------------------
---------------------------------------------------------------------------
| BSIM1 - model input-output parameters - continued |
|--------------------------------------------------------------------------+
|tox Gate oxide thickness in um |
|temp Temperature in degree Celcius |
|vdd Supply voltage to specify mus |
|cgso Gate source overlap capacitance per unit channel width(m) |
---------------------------------------------------------------------------
|cgdo Gate drain overlap capacitance per unit channel width(m) |
|cgbo Gate bulk overlap capacitance per unit channel length(m) |
|xpart Flag for channel charge partitioning |
|rsh Source drain diffusion sheet resistance in ohm per square |
|--------------------------------------------------------------------------+
|js Source drain junction saturation current per unit area |
|pb Source drain junction built in potential |
mj Source drain bottom junction capacitance grading coefficient
|pbsw Source drain side junction capacitance built in potential |
---------------------------------------------------------------------------
|mjsw Source drain side junction capacitance grading coefficient |
|cj Source drain bottom junction capacitance per unit area |
|cjsw Source drain side junction capacitance per unit area |
|wdf Default width of source drain diffusion in um |
|dell Length reduction of source drain diffusion |
---------------------------------------------------------------------------
@node BSIM2 Berkeley Short Channel IGFET Model, Fixed capacitor, BSIM1 Berkeley Short Channel IGFET Model, Model and Device Parameters
@section BSIM2: Berkeley Short Channel IGFET Model
------------------------------------------------------------
| BSIM2 - instance parameters (input-only) |
|-----------------------------------------------------------+
| ic Vector of DS,GS,BS initial voltages |
------------------------------------------------------------
------------------------------------------------------------
| BSIM2 - instance parameters (input-output) |
|-----------------------------------------------------------+
| l Length |
| w Width |
| ad Drain area |
| as Source area |
------------------------------------------------------------
| pd Drain perimeter |
| ps Source perimeter |
| nrd Number of squares in drain |
| nrs Number of squares in source |
|-----------------------------------------------------------+
| off Device is initially off |
| vds Initial D-S voltage |
| vgs Initial G-S voltage |
| vbs Initial B-S voltage |
------------------------------------------------------------
------------------------------------------------------------
| BSIM2 - model parameters (input-only) |
|-----------------------------------------------------------+
| nmos Flag to indicate NMOS |
| pmos Flag to indicate PMOS |
------------------------------------------------------------
------------------------------------------------------------
| BSIM2 - model parameters (input-output) |
|-----------------------------------------------------------+
|vfb Flat band voltage |
|lvfb Length dependence of vfb |
|wvfb Width dependence of vfb |
|phi Strong inversion surface potential |
------------------------------------------------------------
|lphi Length dependence of phi |
|wphi Width dependence of phi |
|k1 Bulk effect coefficient 1 |
|lk1 Length dependence of k1 |
|-----------------------------------------------------------+
|wk1 Width dependence of k1 |
|k2 Bulk effect coefficient 2 |
|lk2 Length dependence of k2 |
|wk2 Width dependence of k2 |
------------------------------------------------------------
|eta0 VDS dependence of threshold voltage at VDD=0
|leta0 Length dependence of eta0 |
|weta0 Width dependence of eta0 |
|etab VBS dependence of eta |
|-----------------------------------------------------------+
|letab Length dependence of etab |
|wetab Width dependence of etab |
|dl Channel length reduction in um |
|dw Channel width reduction in um |
------------------------------------------------------------
|mu0 Low-field mobility, at VDS=0 VGS=VTH |
|mu0b VBS dependence of low-field mobility |
|lmu0b Length dependence of mu0b |
|wmu0b Width dependence of mu0b |
|-----------------------------------------------------------+
|mus0 Mobility at VDS=VDD VGS=VTH |
|lmus0 Length dependence of mus0 |
|wmus0 Width dependence of mus |
|musb VBS dependence of mus |
------------------------------------------------------------
|lmusb Length dependence of musb |
|wmusb Width dependence of musb |
|mu20 VDS dependence of mu in tanh term |
|lmu20 Length dependence of mu20 |
|-----------------------------------------------------------+
|wmu20 Width dependence of mu20 |
|mu2b VBS dependence of mu2 |
|lmu2b Length dependence of mu2b |
|wmu2b Width dependence of mu2b |
------------------------------------------------------------
|mu2g VGS dependence of mu2 |
| continued |
------------------------------------------------------------
------------------------------------------------------------
| BSIM2 - model input-output parameters - continued
|-----------------------------------------------------------+
| lmu2g Length dependence of mu2g |
| wmu2g Width dependence of mu2g |
| mu30 VDS dependence of mu in linear term |
| lmu30 Length dependence of mu30 |
------------------------------------------------------------
| wmu30 Width dependence of mu30 |
| mu3b VBS dependence of mu3 |
| lmu3b Length dependence of mu3b |
| wmu3b Width dependence of mu3b |
|-----------------------------------------------------------+
| mu3g VGS dependence of mu3 |
| lmu3g Length dependence of mu3g |
| wmu3g Width dependence of mu3g |
| mu40 VDS dependence of mu in linear term |
------------------------------------------------------------
| lmu40 Length dependence of mu40 |
| wmu40 Width dependence of mu40 |
| mu4b VBS dependence of mu4 |
| lmu4b Length dependence of mu4b |
|-----------------------------------------------------------+
| wmu4b Width dependence of mu4b |
| mu4g VGS dependence of mu4 |
| lmu4g Length dependence of mu4g |
| wmu4g Width dependence of mu4g |
------------------------------------------------------------
| ua0 Linear VGS dependence of mobility |
| lua0 Length dependence of ua0 |
| wua0 Width dependence of ua0 |
| uab VBS dependence of ua |
|-----------------------------------------------------------+
| luab Length dependence of uab |
| wuab Width dependence of uab |
| ub0 Quadratic VGS dependence of mobility |
| lub0 Length dependence of ub0 |
------------------------------------------------------------
| wub0 Width dependence of ub0 |
| ubb VBS dependence of ub |
| lubb Length dependence of ubb |
| wubb Width dependence of ubb |
|-----------------------------------------------------------+
| u10 VDS depence of mobility |
| lu10 Length dependence of u10 |
wu10 Width dependence of u10
| u1b VBS depence of u1 |
------------------------------------------------------------
| lu1b Length depence of u1b |
| wu1b Width depence of u1b |
| u1d VDS depence of u1 |
| lu1d Length depence of u1d |
|-----------------------------------------------------------+
| wu1d Width depence of u1d |
| n0 Subthreshold slope at VDS=0 VBS=0 |
| ln0 Length dependence of n0 |
| continued |
------------------------------------------------------------
------------------------------------------------------------------------
| BSIM2 - model input-output parameters - continued |
|-----------------------------------------------------------------------+
|wn0 Width dependence of n0 |
|nb VBS dependence of n |
|lnb Length dependence of nb |
|wnb Width dependence of nb |
------------------------------------------------------------------------
|nd VDS dependence of n |
|lnd Length dependence of nd |
|wnd Width dependence of nd |
|vof0 Threshold voltage offset AT VDS=0 VBS=0 |
|-----------------------------------------------------------------------+
|lvof0 Length dependence of vof0 |
|wvof0 Width dependence of vof0 |
|vofb VBS dependence of vof |
|lvofb Length dependence of vofb |
------------------------------------------------------------------------
|wvofb Width dependence of vofb |
|vofd VDS dependence of vof |
|lvofd Length dependence of vofd |
|wvofd Width dependence of vofd |
|-----------------------------------------------------------------------+
|ai0 Pre-factor of hot-electron effect. |
|lai0 Length dependence of ai0 |
|wai0 Width dependence of ai0 |
|aib VBS dependence of ai |
------------------------------------------------------------------------
|laib Length dependence of aib |
|waib Width dependence of aib |
|bi0 Exponential factor of hot-electron effect. |
|lbi0 Length dependence of bi0 |
|-----------------------------------------------------------------------+
|wbi0 Width dependence of bi0 |
|bib VBS dependence of bi |
|lbib Length dependence of bib |
|wbib Width dependence of bib |
------------------------------------------------------------------------
|vghigh Upper bound of the cubic spline function. |
|lvghigh Length dependence of vghigh |
|wvghigh Width dependence of vghigh |
|vglow Lower bound of the cubic spline function. |
|-----------------------------------------------------------------------+
|lvglow Length dependence of vglow |
|wvglow Width dependence of vglow |
|tox Gate oxide thickness in um |
|temp Temperature in degree Celcius |
------------------------------------------------------------------------
|vdd Maximum Vds |
|vgg Maximum Vgs |
|vbb Maximum Vbs |
|cgso Gate source overlap capacitance per unit channel width(m)
|-----------------------------------------------------------------------+
|cgdo Gate drain overlap capacitance per unit channel width(m)|
|cgbo Gate bulk overlap capacitance per unit channel length(m)|
|xpart Flag for channel charge partitioning |
| continued |
------------------------------------------------------------------------
---------------------------------------------------------------------------
| BSIM2 - model input-output parameters - continued |
|--------------------------------------------------------------------------+
|rsh Source drain diffusion sheet resistance in ohm per square |
|js Source drain junction saturation current per unit area |
|pb Source drain junction built in potential |
mj Source drain bottom junction capacitance grading coefficient
| |
---------------------------------------------------------------------------
|pbsw Source drain side junction capacitance built in potential |
|mjsw Source drain side junction capacitance grading coefficient |
|cj Source drain bottom junction capacitance per unit area |
|cjsw Source drain side junction capacitance per unit area |
|wdf Default width of source drain diffusion in um |
|dell Length reduction of source drain diffusion |
---------------------------------------------------------------------------
@node Fixed capacitor, Current controlled current source, BSIM2 Berkeley Short Channel IGFET Model, Model and Device Parameters
@section Capacitor: Fixed capacitor
------------------------------------------------------------
| Capacitor - instance parameters (input-output) |
|-----------------------------------------------------------+
| capacitance Device capacitance |
| ic Initial capacitor voltage |
| w Device width |
| l Device length |
------------------------------------------------------------
------------------------------------------------------------
| Capacitor - instance parameters (output-only) |
|-----------------------------------------------------------+
| i Device current |
| p Instantaneous device power |
------------------------------------------------------------
------------------------------------------------------------
| Capacitor - model parameters (input-only) |
|-----------------------------------------------------------+
| c Capacitor model |
------------------------------------------------------------
------------------------------------------------------------
| Capacitor - model parameters (input-output) |
|-----------------------------------------------------------+
| cj Bottom Capacitance per area |
| cjsw Sidewall capacitance per meter |
| defw Default width |
| narrow width correction factor |
------------------------------------------------------------
@node Current controlled current source, Linear current controlled current source, Fixed capacitor, Model and Device Parameters
@section CCCS: Current controlled current source
------------------------------------------------------------
| CCCS - instance parameters (input-output) |
|-----------------------------------------------------------+
| gain Gain of source |
| control Name of controlling source |
------------------------------------------------------------
------------------------------------------------------------
| CCCS - instance parameters (output-only) |
|-----------------------------------------------------------+
| neg_node Negative node of source |
| pos_node Positive node of source |
| i CCCS output current |
| v CCCS voltage at output |
| p CCCS power |
------------------------------------------------------------
@node Linear current controlled current source, Current controlled ideal switch, Current controlled current source, Model and Device Parameters
@section CCVS: Linear current controlled current source
------------------------------------------------------------
| CCVS - instance parameters (input-output) |
|-----------------------------------------------------------+
| gain Transresistance (gain) |
| control Controlling voltage source |
------------------------------------------------------------
------------------------------------------------------------
| CCVS - instance parameters (output-only) |
|-----------------------------------------------------------+
| pos_node Positive node of source |
| neg_node Negative node of source |
| i CCVS output current |
| v CCVS output voltage |
| p CCVS power |
------------------------------------------------------------
@node Current controlled ideal switch, Junction Diode model, Linear current controlled current source, Model and Device Parameters
@section CSwitch: Current controlled ideal switch
------------------------------------------------------------
| CSwitch - instance parameters (input-only) |
|-----------------------------------------------------------+
| on Initially closed |
| off Initially open |
------------------------------------------------------------
------------------------------------------------------------
| CSwitch - instance parameters (input-output) |
|-----------------------------------------------------------+
| control Name of controlling source |
------------------------------------------------------------
------------------------------------------------------------
| CSwitch - instance parameters (output-only) |
|-----------------------------------------------------------+
| pos_node Positive node of switch |
| neg_node Negative node of switch |
| i Switch current |
| p Instantaneous power |
------------------------------------------------------------
------------------------------------------------------------
| CSwitch - model parameters (input-output) |
|-----------------------------------------------------------+
| csw Current controlled switch model |
| it Threshold current |
| ih Hysterisis current |
| ron Closed resistance |
| roff Open resistance |
------------------------------------------------------------
------------------------------------------------------------
| CSwitch - model parameters (output-only) |
|-----------------------------------------------------------+
| gon Closed conductance |
| goff Open conductance |
------------------------------------------------------------
@node Junction Diode model, Inductor, Current controlled ideal switch, Model and Device Parameters
@section Diode: Junction Diode model
------------------------------------------------------------
| Diode - instance parameters (input-output) |
|-----------------------------------------------------------+
| off Initially off |
| temp Instance temperature |
| ic Initial device voltage |
| area Area factor |
------------------------------------------------------------
------------------------------------------------------------
| Diode - instance parameters (output-only) |
|-----------------------------------------------------------+
| vd Diode voltage |
| id Diode current |
| c Diode current |
| gd Diode conductance |
------------------------------------------------------------
| cd Diode capacitance |
| charge Diode capacitor charge |
| capcur Diode capacitor current |
| p Diode power |
------------------------------------------------------------
------------------------------------------------------------
| Diode - model parameters (input-only) |
|-----------------------------------------------------------+
| d Diode model |
------------------------------------------------------------
------------------------------------------------------------
| Diode - model parameters (input-output) |
|-----------------------------------------------------------+
| is Saturation current |
| tnom Parameter measurement temperature |
| rs Ohmic resistance |
| n Emission Coefficient |
------------------------------------------------------------
| tt Transit Time |
| cjo Junction capacitance |
| cj0 (null) |
| vj Junction potential |
|-----------------------------------------------------------+
| m Grading coefficient |
| eg Activation energy |
| xti Saturation current temperature exp. |
| kf flicker noise coefficient |
------------------------------------------------------------
| af flicker noise exponent |
| fc Forward bias junction fit parameter |
| bv Reverse breakdown voltage |
| ibv Current at reverse breakdown voltage |
------------------------------------------------------------
------------------------------------------------------------
| Diode - model parameters (output-only) |
|-----------------------------------------------------------+
| cond Ohmic conductance |
------------------------------------------------------------
@node Inductor, Mutual inductors, Junction Diode model, Model and Device Parameters
@section Inductor: Inductors
------------------------------------------------------------
| Inductor - instance parameters (input-output) |
|-----------------------------------------------------------+
| inductance Inductance of inductor |
| ic Initial current through inductor |
------------------------------------------------------------
-------------------------------------------------------------
| Inductor - instance parameters (output-only) |
|------------------------------------------------------------+
|flux Flux through inductor |
|v Terminal voltage of inductor |
|volt |
|i Current through the inductor |
|current |
p instantaneous power dissipated by the inductor
| |
-------------------------------------------------------------
@node Mutual inductors, Independent current source, Inductor, Model and Device Parameters
@section mutual: Mutual inductors
------------------------------------------------------------
| mutual - instance parameters (input-output) |
|-----------------------------------------------------------+
| k Mutual inductance |
| coefficient (null) |
| inductor1 First coupled inductor |
| inductor2 Second coupled inductor |
------------------------------------------------------------
@node Independent current source, Junction Field effect transistor, Mutual inductors, Model and Device Parameters
@section Isource: Independent current source
------------------------------------------------------------
| Isource - instance parameters (input-only) |
|-----------------------------------------------------------+
| pulse Pulse description |
| sine Sinusoidal source description |
| sin Sinusoidal source description |
| exp Exponential source description |
------------------------------------------------------------
| pwl Piecewise linear description |
| sffm single freq. FM description |
| ac AC magnitude,phase vector |
| c Current through current source |
| distof1 f1 input for distortion |
| distof2 f2 input for distortion |
------------------------------------------------------------
------------------------------------------------------------
| Isource - instance parameters (input-output) |
|-----------------------------------------------------------+
| dc DC value of source |
| acmag AC magnitude |
| acphase AC phase |
------------------------------------------------------------
------------------------------------------------------------
| Isource - instance parameters (output-only) |
|-----------------------------------------------------------+
| neg_node Negative node of source |
| pos_node Positive node of source |
acreal AC real part
| acimag AC imaginary part |
------------------------------------------------------------
| function Function of the source |
| order Order of the source function |
| coeffs Coefficients of the source |
| v Voltage across the supply |
| p Power supplied by the source |
------------------------------------------------------------
@node Junction Field effect transistor, Lossy transmission line, Independent current source, Model and Device Parameters
@section JFET: Junction Field effect transistor
------------------------------------------------------------
| JFET - instance parameters (input-output) |
|-----------------------------------------------------------+
| off Device initially off |
| ic Initial VDS,VGS vector |
| area Area factor |
| ic-vds Initial D-S voltage |
| ic-vgs Initial G-S volrage |
| temp Instance temperature |
------------------------------------------------------------
---------------------------------------------------------------
| JFET - instance parameters (output-only) |
|--------------------------------------------------------------+
|drain-node Number of drain node |
|gate-node Number of gate node |
|source-node Number of source node |
|drain-prime-node Internal drain node |
---------------------------------------------------------------
|source-prime-nodeInternal source node |
|vgs Voltage G-S |
|vgd Voltage G-D |
|ig Current at gate node |
|--------------------------------------------------------------+
|id Current at drain node |
|is Source current |
|igd Current G-D |
|gm Transconductance |
---------------------------------------------------------------
|gds Conductance D-S |
|ggs Conductance G-S |
|ggd Conductance G-D |
|qgs Charge storage G-S junction |
|--------------------------------------------------------------+
|qgd Charge storage G-D junction |
cqgs Capacitance due to charge storage G-S junction
| |
cqgd Capacitance due to charge storage G-D junction
|p Power dissipated by the JFET |
---------------------------------------------------------------
------------------------------------------------------------
| JFET - model parameters (input-output) |
|-----------------------------------------------------------+
| njf N type JFET model |
| pjf P type JFET model |
| vt0 Threshold voltage |
| vto (null) |
------------------------------------------------------------
| beta Transconductance parameter |
| lambda Channel length modulation param. |
| rd Drain ohmic resistance |
| rs Source ohmic resistance |
| cgs G-S junction capactance |
| continued |
------------------------------------------------------------
------------------------------------------------------------
| JFET - model input-output parameters - continued
|-----------------------------------------------------------+
| cgd G-D junction cap |
| pb Gate junction potential |
| is Gate junction saturation current |
| fc Forward bias junction fit parm. |
------------------------------------------------------------
| b Doping tail parameter |
| tnom parameter measurement temperature |
| kf Flicker Noise Coefficient |
| af Flicker Noise Exponent |
------------------------------------------------------------
------------------------------------------------------------
| JFET - model parameters (output-only) |
|-----------------------------------------------------------+
| type N-type or P-type JFET model |
| gd Drain conductance |
| gs Source conductance |
------------------------------------------------------------
@node Lossy transmission line, GaAs MESFET model, Junction Field effect transistor, Model and Device Parameters
@section LTRA: Lossy transmission line
------------------------------------------------------------
| LTRA - instance parameters (input-only) |
|-----------------------------------------------------------+
| ic Initial condition vector:v1,i1,v2,i2 |
------------------------------------------------------------
------------------------------------------------------------
| LTRA - instance parameters (input-output) |
|-----------------------------------------------------------+
| v1 Initial voltage at end 1 |
| v2 Initial voltage at end 2 |
| i1 Initial current at end 1 |
| i2 Initial current at end 2 |
------------------------------------------------------------
------------------------------------------------------------
| LTRA - instance parameters (output-only) |
|-----------------------------------------------------------+
| pos_node1 Positive node of end 1 of t-line |
| neg_node1 Negative node of end 1 of t.line |
| pos_node2 Positive node of end 2 of t-line |
| neg_node2 Negative node of end 2 of t-line |
------------------------------------------------------------
------------------------------------------------------------
| LTRA - model parameters (input-output) |
|-----------------------------------------------------------+
|ltra LTRA model |
|r Resistance per metre |
|l Inductance per metre |
|g (null) |
------------------------------------------------------------
|c Capacitance per metre |
|len length of line |
|nocontrol No timestep control |
|steplimit always limit timestep to 0.8*(delay of line)
| continued |
------------------------------------------------------------
-----------------------------------------------------------------------------------
| LTRA - model input-output parameters - continued |
|----------------------------------------------------------------------------------+
|nosteplimit don't always limit timestep to 0.8*(delay of line) |
|lininterp use linear interpolation |
|quadinterp use quadratic interpolation |
|mixedinterp use linear interpolation if quadratic results look unacceptable |
-----------------------------------------------------------------------------------
|truncnr use N-R iterations for step calculation in LTRAtrunc |
|truncdontcut don't limit timestep to keep impulse response calculation errors low
|compactrel special reltol for straight line checking |
|compactabs special abstol for straight line checking |
-----------------------------------------------------------------------------------
------------------------------------------------------------
| LTRA - model parameters (output-only) |
|-----------------------------------------------------------+
| rel Rel. rate of change of deriv. for bkpt |
| abs Abs. rate of change of deriv. for bkpt |
------------------------------------------------------------
@node GaAs MESFET model, Level 1 MOSfet model, Lossy transmission line, Model and Device Parameters
@section MES: GaAs MESFET model
------------------------------------------------------------
| MES - instance parameters (input-output) |
|-----------------------------------------------------------+
| area Area factor |
| icvds Initial D-S voltage |
| icvgs Initial G-S voltage |
------------------------------------------------------------
------------------------------------------------------------
| MES - instance parameters (output-only) |
|-----------------------------------------------------------+
|off Device initially off |
|dnode Number of drain node |
|gnode Number of gate node |
|snode Number of source node |
------------------------------------------------------------
|dprimenode Number of internal drain node |
|sprimenode Number of internal source node |
|vgs Gate-Source voltage |
|vgd Gate-Drain voltage |
|-----------------------------------------------------------+
|cg Gate capacitance |
|cd Drain capacitance |
|cgd Gate-Drain capacitance |
|gm Transconductance |
------------------------------------------------------------
|gds Drain-Source conductance |
|ggs Gate-Source conductance |
|ggd Gate-Drain conductance |
|cqgs Capacitance due to gate-source charge storage
|-----------------------------------------------------------+
|cqgd Capacitance due to gate-drain charge storage|
|qgs Gate-Source charge storage |
|qgd Gate-Drain charge storage |
|is Source current |
| continued |
------------------------------------------------------------
------------------------------------------------------------
| MES - instance output-only parameters - continued
|-----------------------------------------------------------+
| p Power dissipated by the mesfet |
-----------------------------------------------------------
------------------------------------------------------------
| MES - model parameters (input-only) |
|-----------------------------------------------------------+
| nmf N type MESfet model |
| pmf P type MESfet model |
------------------------------------------------------------
------------------------------------------------------------
| MES - model parameters (input-output) |
|-----------------------------------------------------------+
| vt0 Pinch-off voltage |
| vto (null) |
| alpha Saturation voltage parameter |
| beta Transconductance parameter |
------------------------------------------------------------
| lambda Channel length modulation parm. |
| b Doping tail extending parameter |
| rd Drain ohmic resistance |
| rs Source ohmic resistance |
|-----------------------------------------------------------+
| cgs G-S junction capacitance |
| cgd G-D junction capacitance |
| pb Gate junction potential |
| is Junction saturation current |
------------------------------------------------------------
| fc Forward bias junction fit parm. |
| kf Flicker noise coefficient |
| af Flicker noise exponent |
------------------------------------------------------------
------------------------------------------------------------
| MES - model parameters (output-only) |
|-----------------------------------------------------------+
| type N-type or P-type MESfet model |
| gd Drain conductance |
| gs Source conductance |
| depl_cap Depletion capacitance |
| vcrit Critical voltage |
------------------------------------------------------------
@node Level 1 MOSfet model, Level 2 MOSfet model, GaAs MESFET model, Model and Device Parameters
@section Mos1: Level 1 MOSfet model with Meyer capacitance model
------------------------------------------------------------
| Mos1 - instance parameters (input-only) |
|-----------------------------------------------------------+
| off Device initially off |
| ic Vector of D-S, G-S, B-S voltages |
------------------------------------------------------------
------------------------------------------------------------
| Mos1 - instance parameters (input-output) |
|-----------------------------------------------------------+
| l Length |
| w Width |
| ad Drain area |
| as Source area |
------------------------------------------------------------
| pd Drain perimeter |
| ps Source perimeter |
| nrd Drain squares |
| nrs Source squares |
|-----------------------------------------------------------+
| icvds Initial D-S voltage |
| icvgs Initial G-S voltage |
| icvbs Initial B-S voltage |
| temp Instance temperature |
------------------------------------------------------------
------------------------------------------------------------
| Mos1 - instance parameters (output-only) |
|-----------------------------------------------------------+
| id Drain current |
| is Source current |
| ig Gate current |
| ib Bulk current |
------------------------------------------------------------
| ibd B-D junction current |
| ibs B-S junction current |
| vgs Gate-Source voltage |
| vds Drain-Source voltage |
|-----------------------------------------------------------+
| vbs Bulk-Source voltage |
| vbd Bulk-Drain voltage |
| dnode Number of the drain node |
| gnode Number of the gate node |
------------------------------------------------------------
| snode Number of the source node |
| bnode Number of the node |
| dnodeprime Number of int. drain node |
| snodeprime Number of int. source node |
|-----------------------------------------------------------+
| von |
| vdsat Saturation drain voltage |
| sourcevcrit Critical source voltage |
| drainvcrit Critical drain voltage |
| rs Source resistance |
| continued |
------------------------------------------------------------
--------------------------------------------------------------
| Mos1 - instance output-only parameters - continued
|-------------------------------------------------------------+
|sourceconductanceConductance of source |
|rd Drain conductance |
|drainconductance Conductance of drain |
|gm Transconductance |
--------------------------------------------------------------
|gds Drain-Source conductance |
|gmb Bulk-Source transconductance |
|gmbs |
|gbd Bulk-Drain conductance |
|-------------------------------------------------------------+
|gbs Bulk-Source conductance |
|cbd Bulk-Drain capacitance |
|cbs Bulk-Source capacitance |
|cgs Gate-Source capacitance |
--------------------------------------------------------------
|cgd Gate-Drain capacitance |
|cgb Gate-Bulk capacitance |
|cqgs Capacitance due to gate-source charge storage
|cqgd Capacitance due to gate-drain charge storage|
|-------------------------------------------------------------+
|cqgb Capacitance due to gate-bulk charge storage |
|cqbd Capacitance due to bulk-drain charge storage|
cqbs Capacitance due to bulk-source charge storage
|cbd0 Zero-Bias B-D junction capacitance |
--------------------------------------------------------------
|cbdsw0 |
|cbs0 Zero-Bias B-S junction capacitance |
|cbssw0 |
|qgs Gate-Source charge storage |
|-------------------------------------------------------------+
|qgd Gate-Drain charge storage |
|qgb Gate-Bulk charge storage |
|qbd Bulk-Drain charge storage |
|qbs Bulk-Source charge storage |
|p Instaneous power |
--------------------------------------------------------------
------------------------------------------------------------
| Mos1 - model parameters (input-only) |
|-----------------------------------------------------------+
| nmos N type MOSfet model |
| pmos P type MOSfet model |
------------------------------------------------------------
------------------------------------------------------------
| Mos1 - model parameters (input-output) |
|-----------------------------------------------------------+
| vto Threshold voltage |
| vt0 (null) |
| kp Transconductance parameter |
| gamma Bulk threshold parameter |
------------------------------------------------------------
| phi Surface potential |
| lambda Channel length modulation |
| rd Drain ohmic resistance |
| continued |
------------------------------------------------------------
------------------------------------------------------------
| Mos1 - model input-output parameters - continued
|-----------------------------------------------------------+
| rs Source ohmic resistance |
| cbd B-D junction capacitance |
| cbs B-S junction capacitance |
| is Bulk junction sat. current |
------------------------------------------------------------
| pb Bulk junction potential |
| cgso Gate-source overlap cap. |
| cgdo Gate-drain overlap cap. |
| cgbo Gate-bulk overlap cap. |
|-----------------------------------------------------------+
| rsh Sheet resistance |
| cj Bottom junction cap per area |
| mj Bottom grading coefficient |
| cjsw Side junction cap per area |
------------------------------------------------------------
| mjsw Side grading coefficient |
| js Bulk jct. sat. current density |
| tox Oxide thickness |
| ld Lateral diffusion |
|-----------------------------------------------------------+
| u0 Surface mobility |
| uo (null) |
| fc Forward bias jct. fit parm. |
| nsub Substrate doping |
------------------------------------------------------------
| tpg Gate type |
| nss Surface state density |
| tnom Parameter measurement temperature |
| kf Flicker noise coefficient |
| af Flicker noise exponent |
------------------------------------------------------------
------------------------------------------------------------
| Mos1 - model parameters (output-only) |
|-----------------------------------------------------------+
| type N-channel or P-channel MOS |
------------------------------------------------------------
@node Level 2 MOSfet model, Level 3 MOSfet model, Level 1 MOSfet model, Model and Device Parameters
@section Mos2: Level 2 MOSfet model with Meyer capacitance model
------------------------------------------------------------
| Mos2 - instance parameters (input-only) |
|-----------------------------------------------------------+
| off Device initially off |
| ic Vector of D-S, G-S, B-S voltages |
------------------------------------------------------------
------------------------------------------------------------
| Mos2 - instance parameters (input-output) |
|-----------------------------------------------------------+
| l Length |
| w Width |
| ad Drain area |
| as Source area |
------------------------------------------------------------
| pd Drain perimeter |
| ps Source perimeter |
| nrd Drain squares |
| nrs Source squares |
|-----------------------------------------------------------+
| icvds Initial D-S voltage |
| icvgs Initial G-S voltage |
| icvbs Initial B-S voltage |
| temp Instance operating temperature |
------------------------------------------------------------
------------------------------------------------------------
| Mos2 - instance parameters (output-only) |
|-----------------------------------------------------------+
| id Drain current |
| cd |
| ibd B-D junction current |
| ibs B-S junction current |
------------------------------------------------------------
| is Source current |
| ig Gate current |
| ib Bulk current |
| vgs Gate-Source voltage |
|-----------------------------------------------------------+
| vds Drain-Source voltage |
| vbs Bulk-Source voltage |
| vbd Bulk-Drain voltage |
| dnode Number of drain node |
------------------------------------------------------------
| gnode Number of gate node |
| snode Number of source node |
| bnode Number of bulk node |
| dnodeprime Number of internal drain node |
|-----------------------------------------------------------+
| snodeprime Number of internal source node |
| von |
| vdsat Saturation drain voltage |
| sourcevcrit Critical source voltage |
| drainvcrit Critical drain voltage |
| continued |
------------------------------------------------------------
--------------------------------------------------------------
| Mos2 - instance output-only parameters - continued
|-------------------------------------------------------------+
|rs Source resistance |
|sourceconductanceSource conductance |
|rd Drain resistance |
|drainconductance Drain conductance |
--------------------------------------------------------------
|gm Transconductance |
|gds Drain-Source conductance |
|gmb Bulk-Source transconductance |
|gmbs |
|-------------------------------------------------------------+
|gbd Bulk-Drain conductance |
|gbs Bulk-Source conductance |
|cbd Bulk-Drain capacitance |
|cbs Bulk-Source capacitance |
--------------------------------------------------------------
|cgs Gate-Source capacitance |
|cgd Gate-Drain capacitance |
|cgb Gate-Bulk capacitance |
|cbd0 Zero-Bias B-D junction capacitance |
|-------------------------------------------------------------+
|cbdsw0 |
|cbs0 Zero-Bias B-S junction capacitance |
|cbssw0 |
cqgs Capacitance due to gate-source charge storage
| |
--------------------------------------------------------------
|cqgd Capacitance due to gate-drain charge storage|
|cqgb Capacitance due to gate-bulk charge storage |
|cqbd Capacitance due to bulk-drain charge storage|
|cqbs Capacitance due to bulk-source charge storage
|-------------------------------------------------------------+
|qgs Gate-Source charge storage |
|qgd Gate-Drain charge storage |
|qgb Gate-Bulk charge storage |
|qbd Bulk-Drain charge storage |
|qbs Bulk-Source charge storage |
|p Instantaneous power |
--------------------------------------------------------------
------------------------------------------------------------
| Mos2 - model parameters (input-only) |
|-----------------------------------------------------------+
| nmos N type MOSfet model |
| pmos P type MOSfet model |
------------------------------------------------------------
------------------------------------------------------------
| Mos2 - model parameters (input-output) |
|-----------------------------------------------------------+
| vto Threshold voltage |
| vt0 (null) |
| kp Transconductance parameter |
| gamma Bulk threshold parameter |
------------------------------------------------------------
| phi Surface potential |
| lambda Channel length modulation |
| rd Drain ohmic resistance |
| rs Source ohmic resistance |
|-----------------------------------------------------------+
| cbd B-D junction capacitance |
| cbs B-S junction capacitance |
| is Bulk junction sat. current |
| pb Bulk junction potential |
------------------------------------------------------------
| cgso Gate-source overlap cap. |
| cgdo Gate-drain overlap cap. |
| cgbo Gate-bulk overlap cap. |
| rsh Sheet resistance |
|-----------------------------------------------------------+
| cj Bottom junction cap per area |
| mj Bottom grading coefficient |
| cjsw Side junction cap per area |
| mjsw Side grading coefficient |
------------------------------------------------------------
| js Bulk jct. sat. current density |
| tox Oxide thickness |
| ld Lateral diffusion |
| u0 Surface mobility |
|-----------------------------------------------------------+
| uo (null) |
| fc Forward bias jct. fit parm. |
| nsub Substrate doping |
| tpg Gate type |
------------------------------------------------------------
| nss Surface state density |
| delta Width effect on threshold |
| uexp Crit. field exp for mob. deg. |
| ucrit Crit. field for mob. degradation |
|-----------------------------------------------------------+
| vmax Maximum carrier drift velocity |
| xj Junction depth |
| neff Total channel charge coeff. |
| nfs Fast surface state density |
------------------------------------------------------------
| tnom Parameter measurement temperature |
| kf Flicker noise coefficient |
| af Flicker noise exponent |
------------------------------------------------------------
------------------------------------------------------------
| Mos2 - model parameters (output-only) |
|-----------------------------------------------------------+
| type N-channel or P-channel MOS |
------------------------------------------------------------
@node Level 3 MOSfet model, Level 6 MOSfet model, Level 2 MOSfet model, Model and Device Parameters
@section Mos3: Level 3 MOSfet model with Meyer capacitance model
------------------------------------------------------------
| Mos3 - instance parameters (input-only) |
|-----------------------------------------------------------+
| off Device initially off |
------------------------------------------------------------
------------------------------------------------------------
| Mos3 - instance parameters (input-output) |
|-----------------------------------------------------------+
| l Length |
| w Width |
| ad Drain area |
| as Source area |
------------------------------------------------------------
| pd Drain perimeter |
| ps Source perimeter |
| nrd Drain squares |
| nrs Source squares |
|-----------------------------------------------------------+
| icvds Initial D-S voltage |
| icvgs Initial G-S voltage |
| icvbs Initial B-S voltage |
| ic Vector of D-S, G-S, B-S voltages |
| temp Instance operating temperature |
------------------------------------------------------------
------------------------------------------------------------
| Mos3 - instance parameters (output-only) |
|-----------------------------------------------------------+
| id Drain current |
| cd Drain current |
| ibd B-D junction current |
| ibs B-S junction current |
------------------------------------------------------------
| is Source current |
| ig Gate current |
| ib Bulk current |
| vgs Gate-Source voltage |
|-----------------------------------------------------------+
| vds Drain-Source voltage |
| vbs Bulk-Source voltage |
| vbd Bulk-Drain voltage |
| dnode Number of drain node |
------------------------------------------------------------
| gnode Number of gate node |
| snode Number of source node |
| bnode Number of bulk node |
| dnodeprime Number of internal drain node |
| snodeprime Number of internal source node |
| continued |
------------------------------------------------------------
--------------------------------------------------------------
| Mos3 - instance output-only parameters - continued
|-------------------------------------------------------------+
|von Turn-on voltage |
|vdsat Saturation drain voltage |
|sourcevcrit Critical source voltage |
|drainvcrit Critical drain voltage |
--------------------------------------------------------------
|rs Source resistance |
|sourceconductanceSource conductance |
|rd Drain resistance |
|drainconductance Drain conductance |
|-------------------------------------------------------------+
|gm Transconductance |
|gds Drain-Source conductance |
|gmb Bulk-Source transconductance |
|gmbs Bulk-Source transconductance |
--------------------------------------------------------------
|gbd Bulk-Drain conductance |
|gbs Bulk-Source conductance |
|cbd Bulk-Drain capacitance |
|cbs Bulk-Source capacitance |
|-------------------------------------------------------------+
|cgs Gate-Source capacitance |
|cgd Gate-Drain capacitance |
|cgb Gate-Bulk capacitance |
cqgs Capacitance due to gate-source charge storage
| |
--------------------------------------------------------------
|cqgd Capacitance due to gate-drain charge storage|
|cqgb Capacitance due to gate-bulk charge storage |
|cqbd Capacitance due to bulk-drain charge storage|
|cqbs Capacitance due to bulk-source charge storage
|-------------------------------------------------------------+
|cbd0 Zero-Bias B-D junction capacitance |
|cbdsw0 Zero-Bias B-D sidewall capacitance |
|cbs0 Zero-Bias B-S junction capacitance |
|cbssw0 Zero-Bias B-S sidewall capacitance |
--------------------------------------------------------------
|qbs Bulk-Source charge storage |
|qgs Gate-Source charge storage |
|qgd Gate-Drain charge storage |
|qgb Gate-Bulk charge storage |
|qbd Bulk-Drain charge storage |
|p Instantaneous power |
--------------------------------------------------------------
------------------------------------------------------------
| Mos3 - model parameters (input-only) |
|-----------------------------------------------------------+
| nmos N type MOSfet model |
| pmos P type MOSfet model |
------------------------------------------------------------
------------------------------------------------------------
| Mos3 - model parameters (input-output) |
|-----------------------------------------------------------+
| vto Threshold voltage |
| vt0 (null) |
| kp Transconductance parameter |
| gamma Bulk threshold parameter |
------------------------------------------------------------
| phi Surface potential |
| rd Drain ohmic resistance |
| rs Source ohmic resistance |
| cbd B-D junction capacitance |
|-----------------------------------------------------------+
| cbs B-S junction capacitance |
| is Bulk junction sat. current |
| pb Bulk junction potential |
| cgso Gate-source overlap cap. |
------------------------------------------------------------
| cgdo Gate-drain overlap cap. |
| cgbo Gate-bulk overlap cap. |
| rsh Sheet resistance |
| cj Bottom junction cap per area |
|-----------------------------------------------------------+
| mj Bottom grading coefficient |
| cjsw Side junction cap per area |
| mjsw Side grading coefficient |
| js Bulk jct. sat. current density |
------------------------------------------------------------
| tox Oxide thickness |
| ld Lateral diffusion |
| u0 Surface mobility |
| uo (null) |
|-----------------------------------------------------------+
| fc Forward bias jct. fit parm. |
| nsub Substrate doping |
| tpg Gate type |
| nss Surface state density |
------------------------------------------------------------
| vmax Maximum carrier drift velocity |
| xj Junction depth |
| nfs Fast surface state density |
| xd Depletion layer width |
|-----------------------------------------------------------+
| alpha Alpha |
| eta Vds dependence of threshold voltage |
| delta Width effect on threshold |
| input_delta (null) |
------------------------------------------------------------
| theta Vgs dependence on mobility |
| kappa Kappa |
| tnom Parameter measurement temperature |
| kf Flicker noise coefficient |
| af Flicker noise exponent |
------------------------------------------------------------
------------------------------------------------------------
| Mos3 - model parameters (output-only) |
|-----------------------------------------------------------+
| type N-channel or P-channel MOS |
------------------------------------------------------------
@node Level 6 MOSfet model, Simple linear resistor, Level 3 MOSfet model, Model and Device Parameters
@section Mos6: Level 6 MOSfet model with Meyer capacitance model
------------------------------------------------------------
| Mos6 - instance parameters (input-only) |
|-----------------------------------------------------------+
| off Device initially off |
| ic Vector of D-S, G-S, B-S voltages |
------------------------------------------------------------
------------------------------------------------------------
| Mos6 - instance parameters (input-output) |
|-----------------------------------------------------------+
| l Length |
| w Width |
| ad Drain area |
| as Source area |
------------------------------------------------------------
| pd Drain perimeter |
| ps Source perimeter |
| nrd Drain squares |
| nrs Source squares |
|-----------------------------------------------------------+
| icvds Initial D-S voltage |
| icvgs Initial G-S voltage |
| icvbs Initial B-S voltage |
| temp Instance temperature |
------------------------------------------------------------
------------------------------------------------------------
| Mos6 - instance parameters (output-only) |
|-----------------------------------------------------------+
| id Drain current |
| cd Drain current |
| is Source current |
| ig Gate current |
------------------------------------------------------------
| ib Bulk current |
| ibs B-S junction capacitance |
| ibd B-D junction capacitance |
| vgs Gate-Source voltage |
|-----------------------------------------------------------+
| vds Drain-Source voltage |
| vbs Bulk-Source voltage |
| vbd Bulk-Drain voltage |
| dnode Number of the drain node |
------------------------------------------------------------
| gnode Number of the gate node |
| snode Number of the source node |
| bnode Number of the node |
| dnodeprime Number of int. drain node |
| snodeprime Number of int. source node |
| continued |
------------------------------------------------------------
--------------------------------------------------------------
| Mos6 - instance output-only parameters - continued
|-------------------------------------------------------------+
|rs Source resistance |
|sourceconductanceSource conductance |
|rd Drain resistance |
|drainconductance Drain conductance |
--------------------------------------------------------------
|von Turn-on voltage |
|vdsat Saturation drain voltage |
|sourcevcrit Critical source voltage |
|drainvcrit Critical drain voltage |
|-------------------------------------------------------------+
|gmbs Bulk-Source transconductance |
|gm Transconductance |
|gds Drain-Source conductance |
|gbd Bulk-Drain conductance |
--------------------------------------------------------------
|gbs Bulk-Source conductance |
|cgs Gate-Source capacitance |
|cgd Gate-Drain capacitance |
|cgb Gate-Bulk capacitance |
|-------------------------------------------------------------+
|cbd Bulk-Drain capacitance |
|cbs Bulk-Source capacitance |
|cbd0 Zero-Bias B-D junction capacitance |
|cbdsw0 |
--------------------------------------------------------------
|cbs0 Zero-Bias B-S junction capacitance |
|cbssw0 |
|cqgs Capacitance due to gate-source charge storage
|cqgd Capacitance due to gate-drain charge storage|
|-------------------------------------------------------------+
|cqgb Capacitance due to gate-bulk charge storage |
|cqbd Capacitance due to bulk-drain charge storage|
cqbs Capacitance due to bulk-source charge storage
|qgs Gate-Source charge storage |
--------------------------------------------------------------
|qgd Gate-Drain charge storage |
|qgb Gate-Bulk charge storage |
|qbd Bulk-Drain charge storage |
|qbs Bulk-Source charge storage |
|p Instaneous power |
--------------------------------------------------------------
------------------------------------------------------------
| Mos6 - model parameters (input-only) |
|-----------------------------------------------------------+
| nmos N type MOSfet model |
| pmos P type MOSfet model |
------------------------------------------------------------
------------------------------------------------------------
| Mos6 - model parameters (input-output) |
|-----------------------------------------------------------+
| vto Threshold voltage |
| vt0 (null) |
| kv Saturation voltage factor |
| nv Saturation voltage coeff. |
------------------------------------------------------------
| kc Saturation current factor |
| nc Saturation current coeff. |
| nvth Threshold voltage coeff. |
| ps Sat. current modification par. |
|-----------------------------------------------------------+
| gamma Bulk threshold parameter |
| gamma1 Bulk threshold parameter 1 |
| sigma Static feedback effect par. |
| phi Surface potential |
------------------------------------------------------------
| lambda Channel length modulation param. |
| lambda0 Channel length modulation param. 0 |
| lambda1 Channel length modulation param. 1 |
| rd Drain ohmic resistance |
|-----------------------------------------------------------+
| rs Source ohmic resistance |
| cbd B-D junction capacitance |
| cbs B-S junction capacitance |
| is Bulk junction sat. current |
------------------------------------------------------------
| pb Bulk junction potential |
| cgso Gate-source overlap cap. |
| cgdo Gate-drain overlap cap. |
| cgbo Gate-bulk overlap cap. |
|-----------------------------------------------------------+
| rsh Sheet resistance |
| cj Bottom junction cap per area |
| mj Bottom grading coefficient |
| cjsw Side junction cap per area |
------------------------------------------------------------
| mjsw Side grading coefficient |
| js Bulk jct. sat. current density |
| ld Lateral diffusion |
| tox Oxide thickness |
|-----------------------------------------------------------+
| u0 Surface mobility |
| uo (null) |
| fc Forward bias jct. fit parm. |
| tpg Gate type |
------------------------------------------------------------
| nsub Substrate doping |
| nss Surface state density |
| tnom Parameter measurement temperature |
------------------------------------------------------------
------------------------------------------------------------
| Mos6 - model parameters (output-only) |
|-----------------------------------------------------------+
| type N-channel or P-channel MOS |
------------------------------------------------------------
@node Simple linear resistor, Ideal voltage controlled switch, Level 6 MOSfet model, Model and Device Parameters
@section Resistor: Simple linear resistor
------------------------------------------------------------
| Resistor - instance parameters (input-output) |
|-----------------------------------------------------------+
| resistance Resistance |
| temp Instance operating temperature |
| l Length |
| w Width |
------------------------------------------------------------
------------------------------------------------------------
| Resistor - instance parameters (output-only) |
|-----------------------------------------------------------+
| i Current |
| p Power |
------------------------------------------------------------
------------------------------------------------------------
| Resistor - model parameters (input-only) |
|-----------------------------------------------------------+
| r Device is a resistor model |
------------------------------------------------------------
------------------------------------------------------------
| Resistor - model parameters (input-output) |
|-----------------------------------------------------------+
| rsh Sheet resistance |
| narrow Narrowing of resistor |
| tc1 First order temp. coefficient |
| tc2 Second order temp. coefficient |
| defw Default device width |
| tnom Parameter measurement temperature |
------------------------------------------------------------
@node Ideal voltage controlled switch, Lossless transmission line, Simple linear resistor, Model and Device Parameters
@section Switch: Ideal voltage controlled switch
------------------------------------------------------------
| Switch - instance parameters (input-only) |
|-----------------------------------------------------------+
| on Switch initially closed |
| off Switch initially open |
------------------------------------------------------------
------------------------------------------------------------
| Switch - instance parameters (input-output) |
|-----------------------------------------------------------+
| pos_node Positive node of switch |
| neg_node Negative node of switch |
------------------------------------------------------------
------------------------------------------------------------
| Switch - instance parameters (output-only) |
|-----------------------------------------------------------+
| cont_p_node Positive contr. node of switch |
| cont_n_node Positive contr. node of switch |
| i Switch current |
| p Switch power |
------------------------------------------------------------
------------------------------------------------------------
| Switch - model parameters (input-output) |
|-----------------------------------------------------------+
| sw Switch model |
| vt Threshold voltage |
| vh Hysteresis voltage |
| ron Resistance when closed |
| roff Resistance when open |
------------------------------------------------------------
------------------------------------------------------------
| Switch - model parameters (output-only) |
|-----------------------------------------------------------+
| gon Conductance when closed |
| goff Conductance when open |
------------------------------------------------------------
@node Lossless transmission line, Voltage controlled current source, Ideal voltage controlled switch, Model and Device Parameters
@section Tranline: Lossless transmission line
------------------------------------------------------------
| Tranline - instance parameters (input-only) |
|-----------------------------------------------------------+
| ic Initial condition vector:v1,i1,v2,i2 |
------------------------------------------------------------
------------------------------------------------------------
| Tranline - instance parameters (input-output) |
|-----------------------------------------------------------+
| z0 Characteristic impedance |
| zo (null) |
| f Frequency |
| td Transmission delay |
------------------------------------------------------------
| nl Normalized length at frequency given |
| v1 Initial voltage at end 1 |
| v2 Initial voltage at end 2 |
| i1 Initial current at end 1 |
| i2 Initial current at end 2 |
------------------------------------------------------------
------------------------------------------------------------
| Tranline - instance parameters (output-only) |
|-----------------------------------------------------------+
| rel Rel. rate of change of deriv. for bkpt |
| abs Abs. rate of change of deriv. for bkpt |
| pos_node1 Positive node of end 1 of t. line |
| neg_node1 Negative node of end 1 of t. line |
------------------------------------------------------------
| pos_node2 Positive node of end 2 of t. line |
| neg_node2 Negative node of end 2 of t. line |
| delays Delayed values of excitation |
------------------------------------------------------------
@node Voltage controlled current source, Voltage controlled voltage source, Lossless transmission line, Model and Device Parameters
@section VCCS: Voltage controlled current source
------------------------------------------------------------
| VCCS - instance parameters (input-only) |
|-----------------------------------------------------------+
| ic Initial condition of controlling source |
------------------------------------------------------------
------------------------------------------------------------
| VCCS - instance parameters (input-output) |
|-----------------------------------------------------------+
| gain Transconductance of source (gain) |
------------------------------------------------------------
------------------------------------------------------------
| VCCS - instance parameters (output-only) |
|-----------------------------------------------------------+
| pos_node Positive node of source |
| neg_node Negative node of source |
| cont_p_node Positive node of contr. source |
| cont_n_node Negative node of contr. source |
------------------------------------------------------------
| i Output current |
| v Voltage across output |
| p Power |
------------------------------------------------------------
@node Voltage controlled voltage source, Independent voltage source, Voltage controlled current source, Model and Device Parameters
@section VCVS: Voltage controlled voltage source
------------------------------------------------------------
| VCVS - instance parameters (input-only) |
|-----------------------------------------------------------+
| ic Initial condition of controlling source |
------------------------------------------------------------
------------------------------------------------------------
| VCVS - instance parameters (input-output) |
|-----------------------------------------------------------+
| gain Voltage gain |
------------------------------------------------------------
------------------------------------------------------------
| VCVS - instance parameters (output-only) |
|-----------------------------------------------------------+
| pos_node Positive node of source |
| neg_node Negative node of source |
| cont_p_node Positive node of contr. source |
cont_n_node Negative node of contr. source
------------------------------------------------------------
| i Output current |
| v Output voltage |
| p Power |
------------------------------------------------------------
@node Independent voltage source, , Voltage controlled voltage source, Model and Device Parameters
@section Vsource: Independent voltage source
------------------------------------------------------------
| Vsource - instance parameters (input-only) |
|-----------------------------------------------------------+
| pulse Pulse description |
| sine Sinusoidal source description |
| sin Sinusoidal source description |
| exp Exponential source description |
------------------------------------------------------------
| pwl Piecewise linear description |
| sffm Single freq. FM descripton |
| ac AC magnitude, phase vector |
| distof1 f1 input for distortion |
| distof2 f2 input for distortion |
------------------------------------------------------------
------------------------------------------------------------
| Vsource - instance parameters (input-output) |
|-----------------------------------------------------------+
| dc D.C. source value |
| acmag A.C. Magnitude |
| acphase A.C. Phase |
------------------------------------------------------------
------------------------------------------------------------
| Vsource - instance parameters (output-only) |
|-----------------------------------------------------------+
| pos_node Positive node of source |
| neg_node Negative node of source |
| function Function of the source |
| order Order of the source function |
------------------------------------------------------------
| coeffs Coefficients for the function |
| acreal AC real part |
| acimag AC imaginary part |
| i Voltage source current |
| p Instantaneous power |
------------------------------------------------------------
@bye
