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Simulators >> Circuit Simulators >> Very slow transient simulation in Spectre with VerilogA model.
https://designers-guide.org/forum/YaBB.pl?num=1453126767

Message started by Jacki on Jan 18^th, 2016, 6:19am

Title: Very slow transient simulation in Spectre with VerilogA model.
Post by Jacki on Jan 18^th, 2016, 6:19am

Hi,

I am doing the transient simulation with a VerilogA model. The VerilogA model is simple, just read in a data file, and do a transition filter when the clock rising edge is coming. The clock is around 10 MHz, not fast, but the data file is a vector includes hundreds of thousands "0" or "1". When I run this VerilogA model in Spectre, it is very slow, I couldn't find the reason. I try to set up cmin, but it doesn't help. About gmin, I want to keep the default value. It is a very simple circuit. Can anybody advise the potential reason causing such slow simulation (around 1 hour run for only 2 ms transient simulation). Even I loose the accuracy from convergence to liberal, it doesn't speed up too much.
Jacki

Title: Re: Very slow transient simulation in Spectre with VerilogA model.
Post by Geoffrey_Coram on Jan 18^th, 2016, 8:10am

If you're using the module you were having trouble with in your previous thread, you might be having a problem when trying to read from a file ($fscanf) on every timepoint.

You may also be misusing the transition filter.

It would probably be best if you could post the module, as you have it now, so we won't be guessing blindly.