[IBIS] Re: hspice vs IBIS model correlation at different capacitive loads

From: Andrew Ingraham <a.ingraham_at_.....>
Date: Wed Jan 04 2006 - 09:30:51 PST
> I think he is saying that the oscillations happen
> because of the feedback in the buffer is trying to
> settle to a steady state condition.
>
> If so, legacy IBIS can not model your buffer, since
> there are no provisions for describing feedback.

Yes.

Although it depends on the feedback.

Linear negative feedback, such as used on op-amps to reduce output
impedance, should work OK, I think.  It's probably also possible that some
forms of feedback to reduce variations in drive strength (for example),
ought to be somewhat compatible with conventional IBIS.  But things like
positive feedback to give hysteresis, don't play well in IBIS.

Regards,
Andy


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Received on Wed Jan 4 09:30:58 2006

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