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Simulators >> Circuit Simulators >> Exceeding blowup limit 1GV!
https://designers-guide.org/forum/YaBB.pl?num=1178197048

Message started by jefkat on May 3^rd, 2007, 5:57am

Title: Exceeding blowup limit 1GV!
Post by jefkat on May 3^rd, 2007, 5:57am

Hi folks,
I was running a transient sim on a DAC when Spectre quit saying voltage at a node exceeded 1GV (the blowup limit). I dont have a nuclear reactor inside my DAC so this must be some simulator thing. Can anyone please tell me how to avoid these kind of pesky things?
thanks much for your taking time to reply.
shaf

Title: Re: Exceeding blowup limit 1GV!
Post by ACWWong on May 3^rd, 2007, 7:19am

classic example of this is an ideal current source, where the current has no where (except via gmin) to go and thus creating blow up voltages... investigate the nodes reported in the spectre log.

Title: Re: Exceeding blowup limit 1GV!
Post by Ken Kundert on May 3^rd, 2007, 8:28am

I have also seen this when there is a negative time constant (due to a negative resistor or the like) causing exponential growth. Try setting diagnose=yes on the options to find the problem.

-Ken

Title: Re: Exceeding blowup limit 1GV!
Post by jefkat on May 4^th, 2007, 12:28am

Thanks a lot guys!