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Simulators >> Circuit Simulators >> Iterative calculation of a mos-model
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Message started by Fabian H. on Oct 22^nd, 2013, 5:30am

Title: Iterative calculation of a mos-model
Post by Fabian H. on Oct 22^nd, 2013, 5:30am

Hello,

I use the software "IC-CAP" from "Agilent", hereby I access to a VerilogA-model of my MOS-transistor.
The external voltage and the flowing current is stored by IC-CAP. In addition, I save myself the calculated values at each call of my model, in a separate file.

The calculation of; cMOS-inverter, nMOS-inverter, CMOS ring oscillator; works well.

But I expect an iterative calculation of the currents and voltages. However, I can't find iterative calculation.
At each call of my model, a true current and voltage value is calculated.

How can I make the iterations visible?

Thank you very much

Title: Re: Iterative calculation of a mos-model
Post by Geoffrey_Coram on Nov 5^th, 2013, 8:35am

The Verilog-A system task $debug is supposed to print for every iteration.

$debug("vds = %g", V(d,s));

But if you have no internal nodes of your model, then it's entirely possible that the simulator just applies the voltages and computes the currents, no iterations necessary, at least for the sorts of simulations IC-CAP does for parameter extraction. I didn't know you could simulate a circuit with IC-CAP.

Title: Re: Iterative calculation of a mos-model
Post by Fabian H. on Nov 10^th, 2013, 11:36pm

Thank you

i used printf() , with debug() it works very good and i can see the iterations.