From owner-ibis-users@eda.org Tue Oct 23 10:41:47 2001 Received: by server.eda.org (8.12.0.Beta7/8.12.0.Beta7) id f9NHevEY005696; Tue, 23 Oct 2001 10:40:57 -0700 (PDT) Content-Class: urn:content-classes:message MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Subject: RE: GND/PWR Clamp Data Collection X-MimeOLE: Produced By Microsoft Exchange V6.0.4712.0 Date: Tue, 23 Oct 2001 13:40:44 -0400 Message-ID: X-MS-Has-Attach: X-MS-TNEF-Correlator: Thread-Topic: GND/PWR Clamp Data Collection Thread-Index: AcFb5ZzQ2+IXnSACSbiLcaxjMwCPYgAArLPi From: "Ingraham, Andrew" To: "ibis-users" X-OriginalArrivalTime: 23 Oct 2001 17:40:45.0032 (UTC) FILETIME=[D7DF2E80:01C15BE9] Content-Transfer-Encoding: 8bit X-MIME-Autoconverted: from quoted-printable to 8bit by server.eda.org id f9NHep7n005693 Sender: owner-ibis-users@eda.org Precedence: bulk Tom Dagostino points out another angle on this question. Perhaps the difference in Clamp curves is seen when the buffer is hi-Z, and the internal node that would have been used to drive the buffer, is pulled high or low. You'd think that this shouldn't have very much effect on the static characteristics of a CMOS buffer. But perhaps some buffers have lots of leakage or something, where you do see this effect. In that case, I figure you ought to take the extremes of both situations and incorporate them into your IBIS curves. After all, both cases will happen in real life. If you are working from a SPICE model, hopefully the model represents reality! Regards, Andy