segabird
Member level 1
I have run a PSS/Pnoise analysis for my sampling & hold circuit. The
structure of circuit is switched capacitor, flip around with a
gain-boosted amplifier. When printing noise summary, I found the top 8
noise contributers (they generated 70% of total noise) are not from
main amplifier, but from gain boost amplifier (AUX amplifier). It's
pretty much way out of my imagination, the noisy amplifier is on the
signal loop though. My PSS/Pnoise setting up are like following:
PSS: 80M beat frequency, number harmonics: 20; time of stable: 300n,
maxacfreq: 1.6G
Pnoise: start: 1, stop: 40M (Nyquist); Max Sideband: 20; Timedomain:
time point 7.1n (hold end point)
To interpret the Pnoise results, I did a noise analysis with a linear
test bench for amplifier (main amplifier with AUX one) only, there most
noise contributers are input and current soure transistors at main
amplifier. It's very interesting that AUX amplifier has shown almost
nothing with total noise this time. Does anyone has any idea with it?
Thanks a lot.
structure of circuit is switched capacitor, flip around with a
gain-boosted amplifier. When printing noise summary, I found the top 8
noise contributers (they generated 70% of total noise) are not from
main amplifier, but from gain boost amplifier (AUX amplifier). It's
pretty much way out of my imagination, the noisy amplifier is on the
signal loop though. My PSS/Pnoise setting up are like following:
PSS: 80M beat frequency, number harmonics: 20; time of stable: 300n,
maxacfreq: 1.6G
Pnoise: start: 1, stop: 40M (Nyquist); Max Sideband: 20; Timedomain:
time point 7.1n (hold end point)
To interpret the Pnoise results, I did a noise analysis with a linear
test bench for amplifier (main amplifier with AUX one) only, there most
noise contributers are input and current soure transistors at main
amplifier. It's very interesting that AUX amplifier has shown almost
nothing with total noise this time. Does anyone has any idea with it?
Thanks a lot.