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Simulators >> Circuit Simulators >> The time in log file doesn't change while simulation is still running.
https://designers-guide.org/forum/YaBB.pl?num=1573291329

Message started by Leila Sharifi on Nov 9^th, 2019, 1:22am

Title: The time in log file doesn't change while simulation is still running.
Post by Leila Sharifi on Nov 9^th, 2019, 1:22am

Hi,

I am simulating a second-order delta-sigma modulator.
my problem is that the simulation suddenly stops without reporting an error. in fact, simulation is still running but the time in log file doesn't change (even after several days!).

The sampling frequency is 2 MHz. I am going to simulate a 4096-point FFT. So I applied an input at the frequency of ((11*2 MHz)/4096).
the maxstep and minstep are set to 10n and 0.1p respectively.

when I reduce the number of FFT points, I don't face this problem. but to have an accurate FFT, I need to simulate it with more points.
for more information, I am using ideal switches in the circuit with Ron=1.5k and Roff=1G.

Could someone guide me for the same, please?

Thank you.

Title: Re: The time in log file doesn't change while simulation is still running.
Post by Ken Kundert on Nov 10^th, 2019, 8:56pm

How ideal are the switches? My experience is that you are usually better off using mos0 transistors to model switches than trying to use idealized switches with switched-capacitor circuits.

-Ken