How to improve the psrr of a bandgap circuit?

[holddreams]

How to improve the psrr of a bandgap circuit?
Does the psrr depend mainly on the opamp?

 

[snoop835]

Use cascode

 

[sunking]

big L

 

[wchu01]

To my knowledge, the bandgap reference is quit okay on PSRR, it is the circuit which you connect up to it that is the issue at hand. I think if some form of better current mirror i.e (cascode config) is used to increase the impedance seen from the supply to the circuit which the bandgap reference is connected to, the PSRR would improved.

 

[marshel]

Use cascode current biasing, if not enough, use RC filter after the bandgap generation.

 

[wwwzhenghao]

i agree:cascode architecture is best.

 

[snoop835]

By putting small value of coupling capacitor can also improve psrr at higher frequency. This journal might be useful

-cheers-

 

[nickoo]

1)casecode structure (impractical for low supply)
2)big L
3)RC filter is not used widely
4)local supply is better stucture but need more area