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PMOS and NMOS folded cascode?

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tumati

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What are the advantages and disadvantages of PMOS input folded cascode vs. NMOS input cascode amplifier? PMOS has smaller flicker noise. What else?
 

An input folded cascode has a better output swing but it has a lower bandwith, larger power consumption, bigger IC area and lower gain than a NMOS telescopic cascode.

This you can find it in the book "Análisis and desig of analog integrated circuits" by Gray and Meyer and ...
 

pmos pm better than nmos because p2 due to nmos cascode is better
 

However, the designer usually prefer a folded cascode because it allow to implement a lower power supply even when the output swing still good (but is the technology of the transistor mainly that allows to lower porwer supply because the threshold voltage goes down).
 

PMOS's substrate can be short to source to eliminate body effect. So better PSRR and CMRR can be achieved. Is it?
 

PMOS is not good than NMOS.for it's large area.
 

The General practice is 1st stage of PMOS and second Stage of NMOS.
reasons
1) PMOS low input flicker noise.
2) Better Slew rate due to larger (Vgs- Vt) for PMOS
3) PMOS ..... can tie the sourse and the substrate connections

Nmos 2nd stage have higher Gm so the effect of 2nd pole due load cap is reduced.
 
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    adix

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