RE: [SI-LIST] : IBIS Subcommittee Formed to Review Spice to

Kellee Crisafulli (
Mon, 07 Jun 1999 12:18:33 -0700


I have a comment on Weston's comment on the number of data points.
I disagree on one point. Instead of increasing the number of points generated
in the IBIS file the spice to IBIS tool should improve the quality of the

I can hand build files with 50 points that out perform files with 400 points.
The big gain is that the FILE SIZE is reduced with higher accuracy.
Large IBIS files will take up many megabytes on 1000's of hard drives.
The V/I and V/T tables are the largest part of IBIS files.
Increasing them 4 x will generally increase the file size 3 x or more.

>The third thing that I changed was the number of points in the time
>waveforms from 50 to 101. I have to remove one point to comply with the
>golden parser, but I get better detail. On the issue of number of points in
>a curve or waveform, I think the user should be able to define any degree of
>granularity and the IBIS creator tool should have an algorithm to remove
>points in linear regions. If the resulting curve still has too many points,
>then increase the linearity tolerance and try it again.

Best wishes...