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Design >> Analog Design >> Output-referred Offset in switched capacitor amplifier
https://designers-guide.org/forum/YaBB.pl?num=1567631566

Message started by vm511 on Sep 4^th, 2019, 2:12pm

Title: Output-referred Offset in switched capacitor amplifier
Post by vm511 on Sep 4^th, 2019, 2:12pm

I am simulating a switched capacitor amplifier without offset cancellation. (In one phase, the input capacitor is connected to the input and in the other to VCM). On adding an artificial input offset using VDC at the input of the amplifier, I would expect the output referred offset to be multiplied by the factor of closed loop gain which is 10 in my case. However, it shows up as a gain of 66dB which is the loop gain (Abeta).
A- Open loop Gain
beta- feedback factor 1/10

Can somebody help with this? Thanks!