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Simulators >> RF Simulators >> pnoise of an oscillator
https://designers-guide.org/forum/YaBB.pl?num=1229578439

Message started by yomnat on Dec 17^th, 2008, 9:33pm

Title: pnoise of an oscillator
Post by yomnat on Dec 17^th, 2008, 9:33pm

Hi,
I'm trying to find the phase noise of a current-controlled oscillator using spectre. The controlling current comes from a bandgap-reference, but the reference current itself is modulating at a lower frequency (due to chopping).
What is the setup/spectre pss@pnoise setting required do this kind of analysis?

Freq(cco) = 1.6GHz
Freq(chopping) = 4MHz

Regards

Title: Re: pnoise of an oscillator
Post by sheldon on Dec 17^th, 2008, 11:20pm

Yomnat,

It sounds like you want to simulate a VCO, an autonomous circuit,
with a driven source, the chopping source. As mentioned in a recent
append Spectre RF will support this analysis from MMSIM71.

from the thread, http://www.designers-guide.org/Forum/YaBB.pl?num=1227668750

Spectre will support the autonomous QPSS ( and corresponding small
signal analyses, like PAC, PXF, PNOISE, etc ) in MMSIM7.1. You can
specify a guess frequency for the LO in the GUI, it is very much like
what you do for the autonomous PSS simulation.

Best Regards,

Sheldon