[SI-LIST] Re: About IBIS error from IBIS check
- From: "Ingraham, Andrew" <Andrew.Ingraham@xxxxxx>
- To: <si-list@xxxxxxxxxxxxx>, <JackWCLin@xxxxxxxxxxxx>
- Date: Wed, 6 Nov 2002 08:12:12 -0500
Jack,
When the IBIS model has V-T curves, ibischk does a quick check to make
sure the steady-state points on the V-T curves are consistent with the
I-V curves.
The initial V-T point represents steady-state (before transient edge has
begun), and the final V-T point ought to be far enough out so that it
has stabilized and reached steady-state as well.
ibischk takes the equivalent load that the IBIS model specifies for the
V-T curves, and applies them to the I-V curves. Their intersections
should be the initial and final V-T points. If they aren't, it
generally means the V-T and I-V data are not consistent with one
another.
An error is flagged if they are not within a certain percentage of
signal. Earlier ibischk programs check the percentage of absolute
voltage, which doesn't work well when the voltage is near zero ... small
voltage differences become huge percentages, and fail the check when
nothing is really wrong. In that case, also check the absolute
voltages. In your case, 2.23V (from V-T) and 2.10V (from I-V) are far
enough different so that you should be concerned.
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 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
Other related posts:
