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Design >> Analog Design >> How to calculate the noise of this SC-amplifier?
https://designers-guide.org/forum/YaBB.pl?num=1329406952

Message started by Jacki on Feb 16^th, 2012, 7:42am

Title: How to calculate the noise of this SC-amplifier?
Post by Jacki on Feb 16^th, 2012, 7:42am

Hello,

I am calculating the integrated noise of this SC-amplifier as shown in the figure. At the beginning, I just calculated the noise at the output of "Voutn" and "Voutp". But my boss tells me I should calculate the noise at the "Voutn' " and "Voutp' ", and his opinion is at that point, it is the real noise of the SC-amplifier.

I check a lot of books and papers, all of the authors calculate the noise at the points "Voutn" and "Voutp". Now if I want to calculate the noise at the points "Voutn' " and "Voutp' ", what I should add? From the clock cycle, it is a new period, and the OTA is open loop. Should I add both the OTA noise and sampling noise of switch again? Also at least from my simulation experience, the integrated noise of OTA in open loop (in continuous time simulation) is very high. From the simulation, I compare the integrated noise of the SC-amplifier at "Voutn/Voutp" and "Voutn'/Voutp' ", the former one has smaller noise, almost 1/3 integrated noise of the latter one, and the noise has the unit square volt "V2".

Anybody can give me some hints? Thank you very much![img][/img]