intent to handle multiple isolated substrate regions. A previous
version of this was added to the master branch but that method had
too many issues and is being deprecated. This version is also very
experimental and is a work in progress.
restricted to its original intent, which is to replace the long name
formed from the plane short name and the "minfinity" coordinate.
This avoids issues with conflicting substrate names derived from a
real layer such as pwell. Also, the global substrate node name now
returns the variable name without the "$" in front if the variable
has not been set to anything. This avoids potential syntax errors
in the netlist.
include (1) specification of sidewall or surface to use for
each type individually, rather than a single method for all
types, and (2) specification of a linear model R = Ax + B for
the ratio limit when diodes are attached to the wire, where x
is the diode surface area (unitless, as this is a ratio).
checks. Added new command "antennacheck" and a routine that
adds feedback entries where violations are found. Extended the
syntax of the extraction section of the techfile to support the
antenna ratios and antenna calculation methods.
principle layer name, which should not happen (especially in the
case of space, where layers may be aliased to "space" to make them
ignored on input). Also: Implemented a "-<types>" option to the
"substrate" record in the techfile to declare types which shield
layers from the substrate. This allows types like pwell to be used
in different contexts, e.g., as part of the substrate, or as a P-well
in deep N-well, without requiring a different type. This works in
conjunction with the recently-implemented "+<types>" ID types for
devices. All of this may seem unnecessary but helps to reduce the
number of layers needing to be defined, and the subsequent complexity
of the DRC rulesets.
to be more robust and not depend on the ordering of the devices in
the techfile. The extraction method now keeps a mask of which
properties of the device (source/drain types, substrate type,
identifier type) have been found, and will look only for device
records that match what is known about the device. Added a device
identifier record which is the last record before parameters if the
record begins with "+". This allows marker layers to be placed
over a device such that it will extract with a different type.
This helps reduce the complexity of the techfile and allows
certain specialized devices like RF or ESD to be identified without
a separate layer type for the device.
Tim Edwards