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Big Contributor of Phase Noise in Hysteresis Buffer (Read 10943 times)

vp1953

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Re: Big Contributor of Phase Noise in Hysteresis Buffer
Reply #15 - Sep 20^th, 2010, 6:36pm

Hi Pancho

Quote:

Contribution of fricker noise to sideband noise could be larger for sharp transition since conversion gain is larger.

After thinking about this a little bit, I completely agree with you - this could be the reason. Basically stationary noise sources get convolved with response of the circuit to give your usb noise behaviour.

If flicker noise comes down with with increasing W, and USB noise increases with W, then the spectral components (fourier components, not PSD) at the output of your hysteretic invertor must increase by factor between varying between W^1/2 and W (a first order calculation). Is this the case for your circuit?

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Lex Senior Member Offline Posts: 201 Eindhoven, Holland	Re: Big Contributor of Phase Noise in Hysteresis Buffer Reply #16 - Sep 22^nd, 2010, 4:11am I fear that the results of the upconversion of 1/f noise of the switches are not that accurate. Did you checked the papers from Klumperink on this specific topic?
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pancho_hideboo

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Re: Big Contributor of Phase Noise in Hysteresis Buffer
Reply #17 - Sep 22^nd, 2010, 6:34am

Lex wrote on Sep 22^nd, 2010, 4:11am:

I fear that the results of the upconversion of 1/f noise of the switches are not that accurate.
Did you checked the papers from Klumperink on this specific topic?

See http://www.designers-guide.org/Forum/YaBB.pl?num=1285083976

Fricker noise contribution is treated as upconversion from DC in any slave small noise analysis subjected to master large signal steady state analysis.

What are you fearing.

Indeed we can never evaluate sideband noise of very small offset frequency from carrier accurately even if we use any commercial simulator.
http://www.designers-guide.org/Forum/YaBB.pl?num=1050465395/20#20
http://www.designers-guide.org/Forum/YaBB.pl?num=1050465395/26#26
http://www.designers-guide.org/Forum/YaBB.pl?num=1263835149/6#6
http://www.designers-guide.org/Forum/YaBB.pl?num=1260521995/5#5

« Last Edit: Sep 22^nd, 2010, 12:11pm by pancho_hideboo »

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