(Sorry if this is a repeat ... my first reply doesn't seem to be getting to the list, so I'm sending it again.) Your IBIS model faithfully duplicates what the SPICE model did under those circumstances. It is probably just a warning (not an error), letting you know that the currents were on the high side for real silicon, but it doesn't necessarily mean something is wrong. That part of the SPICE-to-IBIS translation is stressing the silicon in a way that it may not normally be used. If you were happy with the SPICE model before, then be happy with the IBIS model too. On the other hand, this experience has probably taught you that your old trusty SPICE model was probably somewhat limited in its handling of extreme overshoots. Most of the time this isn't an issue for anybody, because the model (even though its clamp currents may have been impractically large) did direct the simulation to do the right thing (i.e., clamp the voltage), and the waveform might be essentially the same whether the clamping current was 0.7A or 70A. IBIS won't care (in spite of its warning). However, in some cases the time-domain results might not correlate well with real silicon, and then you would want to fix the SPICE model. The justification for fixing it is NOT because the IBIS model causes those warnings. It's because the SPICE model wasn't accurate in the first place. Regards, Andy ------------------------------------------------------------------ To unsubscribe from si-list: si-list-request@xxxxxxxxxxxxx with 'unsubscribe' in the Subject field or to administer your membership from a web page, go to: //www.freelists.org/webpage/si-list For help: si-list-request@xxxxxxxxxxxxx with 'help' in the Subject field List FAQ wiki page is located at: http://si-list.org/wiki/wiki.pl?Si-List_FAQ List technical documents are available at: http://www.si-list.org List archives are viewable at: //www.freelists.org/archives/si-list or at our remote archives: http://groups.yahoo.com/group/si-list/messages Old (prior to June 6, 2001) list archives are viewable at: http://www.qsl.net/wb6tpu