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Measurements >> Phase Noise and Jitter Measurements >> PLL phase noise simulatioon using spectreRF
https://designers-guide.org/forum/YaBB.pl?num=1299114250

Message started by Dinesh Agarwal on Mar 2^nd, 2011, 5:04pm

Title: PLL phase noise simulatioon using spectreRF
Post by Dinesh Agarwal on Mar 2^nd, 2011, 5:04pm

1. I could simulate the phase noise of PFD+CP+LP using PSS and Pnoise simulation.
2. In second case only PFD+Cp was included for same setup.

The result in both the cases are same. Is this right, i think there should some difference in twocases, as there is resistance thermal noise in LP

Pls comment

Title: Re: PLL phase noise simulatioon using spectreRF
Post by rajkumar palwai on Apr 10^th, 2011, 3:42am

Hi Dinesh,
What is the freq range of your pss+pnoise simulation? If u are simulating at low freq, then your CP flicker noise can be so dominant that you are unable to see the filter resistor thermal noise contribution.

regards
rajkumar