vivkr
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Hi Rajesh,
It would be quite hard to find a paper on this subject. There was a paper by Sansen and others in JSSC titled "CMRR and PSRR of ..." but I don't have the exact link to it. Perhaps you can try searching on IEEE Xplore for JSSC papers by Sansen. It is a brief paper.
Some information may be found in the JSSC paper by B K Ahuja "An improved frequency compensation technique ...", Dec. 1983.
I assume you are talking of fully differential amps. Basically, you can improve PSRR by increasing the impedance between the supplies and the output => more impedance => swing reduction or need for more gain. This is typically the standard tradeoff, and also holds well for cascoding.
If a differential amplifier is designed in such a manner that any excitation from the supply shows up as an identical disturbance on both halves of the differential path (magnitude and phase), then you have a high PSRR. So, you need excellent matching.
Also, in single-ended amps, there are other effects at work. These suffer from inherent asymmetries that reduce PSRR. For instance, in a current mirror, VGS is the same for both halves, but VDS not, and this will cause reduction in PSRR. In a 2-stage amp, you have poor PSRR beyond the unity-gain bandwidth (see Ahuja paper).
Regards Vivek
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