[SI-LIST] : W-element Simulation

Doug Day (day_d@sanjose.vlsi.com)
Sun, 28 Sep 1997 09:25:40 -0700

I am currently trying to simulate a package with a W-element model.
I have borken the model into 4 sections for convenience (it is a 4
row BGA) This yields very small delays for each segment (4 - 6 ps).
When I simulate I get the following error on my console:

hspice ttlio3.sp > ! t
sqrt: DOMAIN error
sqrt: DOMAIN error
sqrt: DOMAIN error
time: command terminated abnormally.

THe number of times "sqrt: DOMAIN error" is repeated seems to have a direct
relationship to the data in my .rlc file. I can change some numbers and get it
to occur more times but can not get it go away.

I believe that it is either related the short delay I am using and possibly
a time step error but I am not sure.

Has anyone else seen errors similar to this?

Thanks

**************************************************
Douglas Day
Applications Engineering Manager
High Speed Interface
Communications Products Division
VLSI Technology Inc.
TEL: 408-434-7660
FAX: 408-434-7866
*************************************************