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Simulators >> RF Simulators >> VCO jitter
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Message started by lianggu on Apr 23^rd, 2008, 12:36pm

Title: VCO jitter
Post by lianggu on Apr 23^rd, 2008, 12:36pm

When I use (74) and (78) in "predicting the phase noise and jitter of PLL based frequency synthesizers" to calculate VCO jitter, however, the result is very different from what I get when I use (14) in JSSC 2006, p. 1806.
I am very confused. Which one is right?

Title: Re: VCO jitter
Post by pancho_hideboo on Apr 24^th, 2008, 12:10am

lianggu wrote on Apr 23^rd, 2008, 12:36pm:

Who can understand your question ?

"predicting the phase noise and jitter of PLL based frequency synthesizers" is paper's title in JSSC 2006, p.1806 ?
If so, you should show author's name and number of JSSC or published month.

What are (74), (78) and (14) ?
Are they equation's number ?

Do you refer to the following paper and equations in it ?
I can't find (74) and (78) in it.

TITLE: Phase noise and jitter in CMOS ring oscillators
ISSUE: IEEE Journal of Solid-State Circuits, vol. 41, pp. 1803 - 1816, August 2006
AUTHORS: Asad A. Abidi
BIBLIOGRAPHIC ENTRY:
A. A. Abidi, "Phase noise and jitter in CMOS ring oscillators," IEEE Journal of Solid-State Circuits, vol. 41, pp. 1803 - 1816, August 2006.

Title: Re: VCO jitter
Post by lianggu on Apr 25^th, 2008, 9:44am

"predicting the phase noise and jitter of PLL based frequency synthesizers" is NOT a JSSC paper. it is posted on this website. Ken Kundert is the author. Its version is 4g, August 2006. Equations (74) and (78) in this pater give a method how to calculate VCO jitter based on phase noise.

Abidi's "Phase noise and jitter in CMOS ring oscillators", JSSC 2006, p1803-p1816 gives another equation (14) to calculate VCO jitter based on phase noise.

But I can not get the same results when I use Ken's and Abidi's methods.