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Design >> Mixed-Signal Design >> Phase noise analysis
https://designers-guide.org/forum/YaBB.pl?num=1190840524

Message started by pll_boy on Sep 26^th, 2007, 2:02pm

Title: Phase noise analysis
Post by pll_boy on Sep 26^th, 2007, 2:02pm

hi all,

i have a oscillator followed by frequency multiplier, i wanted to know the phase noise chaterstics at output of frequency multiplier.

i use cadence for simulation of my circuit,

problem is chosing the oscillator i am getting diffrent Phase noise charaterstic when i choose 1)oscillator as oscillator
2)frequency multiplier output as oscillator
can u tell me what is the write output(oscillator) to choose

Title: Re: Phase noise analysis
Post by Stefan on Sep 26^th, 2007, 11:55pm

That's not a problem, that's a feature !
Are you sure you're having a frequency _multiplier_ ?
In general a frequency multiplier is another PLL which would have it's own phase noise characteristics ...

Title: Re: Phase noise analysis
Post by pll_boy on Sep 27^th, 2007, 11:45am

Thanks stefen
I am measuring phase noise at output of frequency multplier
problem is when in PSS analysis i have to chose oscillator node,
so my Question is what oscillator nodes i have to choose in pss analysis,is it oscillator output or frequency multiplier output(for both i am getting diffrent phase noise results what is the correct one)
and why

Title: Re: Phase noise analysis
Post by Stefan on Oct 3^rd, 2007, 3:07am

Okay let's ask different .. how did you implement your frequency multiplier ?