RE: [SI-LIST] : Convert an IBIS model to SPICE Model.

John Synesiou (
Thu, 2 Apr 1998 14:56:20 -0600


Your solution is one way to solve this problem in SPICE, but a far easier
method would be to use a SPICE simulators that can do behavioral modeling
using lookup tables. Some examples are SPICE 3 B-elements with if-then-else
extensions, or XSPICE extensions (many SPICE vendors offer XSPICE


John Synesiou
U.S. Power, Inc Phone (612)826-1111
6497 City West Parkway Fax (612)826-1003
Eden Prairie Date: 04/02/98
MN, 55344 Time: 2:44 PM

-----Original Message-----
From: owner-si-list@silab.Eng.Sun.COM
[mailto:owner-si-list@silab.Eng.Sun.COM] On Behalf Of D. C. Sessions
Sent: Thursday, April 02, 1998 8:53 AM
Subject: Re: [SI-LIST] : Convert an IBIS model to SPICE Model.

John Lin - TAO wrote:
> SI experts,
> How do I construct a SPICE model from an IBIS model?

That depends on the SPICE simulator. The syntax for
piecewise-linear transconductance elements differs
from one to another. Time-domain behavior is even
more interesting; basically, you have to take the
four V/T curves and back them through the V/I curves
to get turnon and turnoff profiles for the pullup
and pulldown devices, then make up a subcircuit
that modulates the transconductances to get the
same result.

D. C. Sessions