RE: Simulation resolution weirdness

There are limitations and imperfections in all circuit simulators. (You
didn't mention which simulator program you are using, which might help
others to help you.) Some programs are better than others. These problems
can be finicky and difficult to avoid.

Yours sounds like a "numerical oscillation" problem, which occasionally
happens in SPICE or SPICE-like simulators. In your case, it apparently
happens to be made worse by certain time resolution settings. There are
likely some controls (such as the Method=Gear vs. Trap setting in SPICE)
that may help here.

Regards,
Andy

> ----------
> From: mark.browne@nokia.com[SMTP:mark.browne@nokia.com]
> Sent: Tue, 19 September 2000, 05:25
> To: ibis-users@eda.org
> Subject: Simulation resolution weirdness
>
> Hi all,
>
> I am fairly new to using IBIS, so I am hoping that the symptoms that I am
> getting will strike a chord with someone out there.
>
> I have run the same simulation several times, changing only the time
> resolution each time. When the resolution is set to 20ps, the results
> look
> fine. However, at 15ps the resultant waveform is just an increasing
> oscillation, and at 10ps it look like a range of mountains.
>
> Obviously I am misusing the method somehow - all I need is for someone to
> tell me how.
>
> Any ideas?
>
> Mark Browne
> Senior Engineer
> Nokia UK Ltd.
>
 
Received on Tue Sep 19 05:16:08 2000