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Modeling >> Semiconductor Devices >> Flicker Noise Under Switched Biasing
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Message started by aaron_do on May 17^th, 2008, 1:21am

Title: Flicker Noise Under Switched Biasing
Post by aaron_do on May 17^th, 2008, 1:21am

Hi all,

just wondering if anyone is familiar with flicker noise reduction using switched biasing. I have two questions...

1) Does the flicker noise reduction only occur for OFF/SAT or will it also occur for LIN/SAT assuming both result in IDS=0 during the OFF or LIN state?

2) It seems to only occur at quite low frequencies (1 kHz) compared to a normal flicker noise corner (1 MHz). Is that right?

thanks for any input,
Aaron

Title: Re: Flicker Noise Under Switched Biasing
Post by Geoffrey_Coram on May 19^th, 2008, 6:12am

1) You'll get some reduction due to the duty cycle, of course. But I think the main reduction won't be seen for LIN/SAT, because the channel still exists, and the trapped carriers aren't freed. When doing OFF/SAT, the channel disappears in OFF and the carriers are much more likely to come out of the traps than go in, so when the next SAT portion occurs, there are far fewer trapped carriers to be causing the flicker noise.