vivkr
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I am trying to simulate a very highly accurate circuit, and am not very sure if the errors I see are due to the circuit or the simulator. My circuit is a switched-capacitor filter.
I tightened all the accuracy parameters considerably (reltol, abstol) and set relref to "pointlocal". I am also using gear2 integration method to prevent trapezoidal ringing.
However, I see the following dialog
"Convergence difficulties resulted in error requirements being unsatisfied".
I don't know how much simulator error I have now, and hence it is very difficult to get a reliable estimate for the error in the charge-transfer process.
I looked up the guidelines in the "Designer's Guide to Spice & Spectre" and try to use as many of those as I can to achieve better convergence. I cannot use "gmin" as I have a charge-transfer going on, but I use "cmin".
Could someone suggest some tips for improving convergence and accuracy in Spectre transient analysis?
Many thanks and Best Regards Vivek
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