hi raja,
Quote:1.Why none of the book is discussing frequency response, normally how much phase margin people target?
Maybe, noone talks about bandgap frequency response because bandgap is a very slow circuit...
Quote:2.I feel op amp output is the best place to compensate, because by putting cap between vdd and opamp output any noise in the vdd won't enter in the circuit, but in one paper they claimed that this will cap will increase noise, can any one please explain this.
No, i agree with the paper...Placing a cap b/w opamp o/p node and VDD will directly couple any high frequency Noise into the ckt...thereby degrading PSRR at higher Frequencies...
Quote:3. How to decide error amp bandwidth?
I am myself not much sure about this....But i guess, you choose it depending on the noise profile of your supply, and the BW of the bandgap ckt.Maybe some senior can help...
--mayank