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Clarify use of 'optran' command

This commit is contained in:
Holger Vogt 2021-03-28 11:39:04 +02:00
parent 2ef3f66f96
commit 893ce7879f
1 changed files with 16 additions and 7 deletions
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README.optran
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@ -12,12 +12,28 @@ If this fails:
If this again fails, bail out. If this again fails, bail out.
Step 1 may be skipped by
option noopiter
Step 2 may be skipped by
option gminsteps=0
Step 3 may be skipped by
option srcsteps=0
In this branch a fourth method is added: In this branch a fourth method is added:
4) Start a transient simulation for a specific amount of time. 4) Start a transient simulation for a specific amount of time.
Keep all data local. Keep the matrix values as an Keep all data local. Keep the matrix values as an
operating point for the simulation following. operating point for the simulation following.
If this fails, finally stop. If this fails, finally stop.
Operating point by transient is initiated by the command 'optran'.
The first three entries will override noopiter, gminsteps, srcsteps.
A typical command may be
optran 0 0 0 50u 10m 0
(no initial iteration, no gmin stepping, no source stepping,
stepsize for optran 50 us, optran run until 10 ms, no supply ramping
The time for transient is determined a priori. If a transient The time for transient is determined a priori. If a transient
simulation follows, choose 100 time the TSTEP value. If an ac simulation follows, choose 100 time the TSTEP value. If an ac
or noise simulation follows, take the inverted starting or noise simulation follows, take the inverted starting
@ -26,14 +42,7 @@ frequency divided by 10 as the optran simulation time.
A method to stop the op transient simulation, when all nodes A method to stop the op transient simulation, when all nodes
have become stable, might be desirable, but has not yet been implemented. have become stable, might be desirable, but has not yet been implemented.
Step 1 may be skipped by
option noopiter
Step 2 may be skipped by
option gminsteps=0
Step 3 may be skipped by
option srcsteps=0
The transient op calculation uses the 'UIC' flag for its startup. The transient op calculation uses the 'UIC' flag for its startup.
Basically two applications come to mind: You may use this with Basically two applications come to mind: You may use this with