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Simulators >> Circuit Simulators >> SOI Convergence Problems
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Message started by emad on May 24^th, 2009, 11:43am

Title: SOI Convergence Problems
Post by emad on May 24^th, 2009, 11:43am

Hello everyone:

I have convergence problems for DC and Tran using SOI devices. Even for a simple circuit like an inverter, it wouldn't converge unless I use trapezoidal and make tolerances really loose. Is this normal? Any ideas on how to improve convergence of SOI circuits?

Thanks

Title: Re: SOI Convergence Problems
Post by Geoffrey_Coram on May 26^th, 2009, 5:41am

What models -- BSIMSOI?

I don't expect trapezoidal is helping your DC convergence (unless it's pseudo-tran); I guess I'd be surprised if changing the tolerances makes DC work better, either -- once you're close, Newton's method should work quite well to reduce the error, unless there's some error in the derivatives of the model (and if you're far away so Newton isn't quadratically converging, then increasing tolerances isn't likely to help).