Re: [ng-spice] Readline Response
>
>
> On Wed, 25 Aug 1999, Michele Quarantelli wrote:
>
> > Traditional transient analysis is based on a direct integration
> > of circuit equations using some kind of BDF. This approach definitively
>cov
> ers
> > most of the designer's need. However, when dealing with high frequency (>
> > 100Meg) systems where signals with very different time scales exist the
> > analysis has to be carried out with a very fine time-step to "catch" the
> > fastest signal and long enough to cover the entire low frequency signal
> > spectrum (e.g. a mixer working at 900meg downconverting a 200k signal).
> > The traditional approach in this case doesn't fit very well ...
> > Different algorithms have been developed to solve the time domain steady
>st
> ate
> > condition of a circuit and I mentioned some of them up above ... I'm sure
>y
> ou
> > have heard of commercial simulators like Spectre, Harmonica, etc ...
>which
> > implement some of the above algorithms.
> > It would be nice to have some of them included ...
> Yes, have heard of them but never used Spectre or Harmonica and do not
> know the algorithms you mention, someone else knows them ?
>
>
> > A final note: I'm currently comparing the last release of Berkeley Spice
> > (spice3f5fix) against ng-spice. During op simulation of a LNA amplifier
> > (including a grounded MOS device as a capacitor) I saw ng-spice
>converging
> to
> > the wrong solution (i.e. vds not equal to zero) !!! I was using MOSIS
>BSIM3
> v1
> > model so I re-compiled the bsim3v1 code (with some modification ... of
>cour
> se)
> > and ... same result !!! At this point I'm quite concerned with ng-spice
> > reliability ... Anyone having the same problem ?
> ng-spice reliability is still to be tested. We changed the code in various
> parts, and probably exploited an hidden bug (or inserted a new one). Can
> you send to the list the netlist and modelcards so that we can perform our
> simulations and try to discover the bug ?
>
Unfortunately I cannot release the netlist so far, but I'll try with some
other circuit to see if I fall into the same pit.
> Anyway: did you compiled in the bsim3v1 code included in spice3f5fix or
> another one ? I had the same problem linkng all three B3SOI models in a
> single executable: the PD model did not converged for one test circuit,
> while the spice compiled with the PD model only converged. May be I have
> not understood something in device code.
>
I used the bsim3 code from spice3f5fix plus I added the test for compatibility
with Cider implementation.
>
> > Also how do I access the develpment release ? I tried anonymous cvs but
>it
> > didn't work .
>
> the login is anonymous and password: guest
> you need to: export
> CVSROOT=:pserver:anonymous@ieee.ing.uniroma1.it:/var/services/cvsroot
>
> then launch the command:
>
> cvs login
>
> if it does not works, try:
>
> cvs -d :pserver:anonymous@ieee.ing.uniroma1.it:/var/services/cvsroot login
>
> you will be requested for a password: guest,
>
> and then you can do your job (there is no confirmation for the login
> procedure).
>
> Paolo
>
OK I will try again ... I'll let you know.
Michele
Partial thread listing:
- Re: [ng-spice] Readline Response, (continued)