Ultrasim: convergence problem in transient analysis

[Vitamin-C]

Ultrasim question

Anyone is using ultrasim for 5000+ transistor simulation?
Do you encounter convergence problem in transient analysis?
I have tried nearly all the option, sim_mode, trtol, speed ....
and can't make it converge.
It does running at the beginning but at a centain instant, the convergence problem will happen?

any share is welcomed!

 

[cristianb]

Re: Ultrasim question

What kind of circuit do you have into this 500+simulation because varios convergence problem can be linked with diffent circuit types and what is specific convergence error message that you get from USIM?