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Design >> Analog Design >> A question on STB analysis of OSC
https://designers-guide.org/forum/YaBB.pl?num=1733144873

Message started by chang830 on Dec 2^nd, 2024, 5:07am

Title: A question on STB analysis of OSC
Post by chang830 on Dec 2^nd, 2024, 5:07am

Hi , I have a problem on simulation of xtal oscillator. When I simulatie a Santos xtal OSC, I use STB to get its gainmargin which I found it is -1.5dB.So it should not to oscillate, but I found it can oscillate corectly when I use transisent analysis. Can anyone explain this descranpcy?

Thanks a lot!

Title: Re: A question on STB analysis of OSC
Post by sheldon on Dec 2^nd, 2024, 10:39am

Chang,

Are you using stability analysis or periodic stability analysis?

Sheldon

Title: Re: A question on STB analysis of OSC
Post by chang830 on Dec 2^nd, 2024, 5:35pm

Dear Sheldon， I use stability analysis. I think in the beginning of the buildup, it is linear.