[SOLVED] How to determine the parameter of OPAMP for Bandgap

[jiangwp]

For a BandGap, there must be OP.

But how are the parameters(Gain, BandWidth, noise, psrr, cmrr, SlewRate) determied.

 

[ambreesh]

First have a very low-offset amplifier.
Also have high gain.
Your amplifier output shall drive the gate of PMOS, that pumps the PTAT current in the resistor and diode chain. Thus your opamp architecture must pass the complete supply ripple to gate of the PMOS this way supply ripple would be common mode signal.
Depending on the application you have to think on the noise aspect of it. BGR are noisy circuits.
Hope it helps.