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Simulators >> Circuit Simulators >> How to set up and simulate a switched-capacitor CMFB?
https://designers-guide.org/forum/YaBB.pl?num=1334596276

Message started by Jacki on Apr 16^th, 2012, 10:11am

Title: How to set up and simulate a switched-capacitor CMFB?
Post by Jacki on Apr 16^th, 2012, 10:11am

Hello,

I am simulating a switched-capacitor amplifier, it is the simple and typical fully differential SC-amp, with the gain of 2. At the beginning, I use continuous CMFB, it works well. Now I am trying to use SC-CMFB as shown in the book (by Paul R. Gray), but I always have the problem of converge for both Trans. and PSS simulation. Then the simulation is crashed.

I am using Spectre, in transient simulation, I set the "skip dc", I use "gear2only", also I set ic "all".

Does anybody have the experience about simulating SC-CMFB?

Thank you.

Title: Re: How to set up and simulate a switched-capacitor CMFB?
Post by boe on Apr 16^th, 2012, 10:24am

Jacki,
A simulator crash is a tool bug.

- B O E

Title: Re: How to set up and simulate a switched-capacitor CMFB?
Post by Jacki on Apr 17^th, 2012, 9:17am

Hello Boe,

Thank you for your reply.

I solve the problem, because I am using the ideal switch from analogLib, I set the on-resistor and off-resistor as the default value, that is crazy. Now I change them to the reliable one. Spectre works.

Jacki