What are roles of capacitors in switched capacitor integrors

[sehun1119]

Hi, all,

I am studying SC Sigma Delta ADC, and have questions on an integrator part.

The switched capacitor integrator consists of OP-amp, switches and capacitors, and I wonder how the capacitors affect the performance of integrators or Sigma Delta Modulator.

To my knowledge, the transfer function of the integrator does not depend on their values of two capacitors but depends on the ratio of two capacitors.

Then, what other effects do these capacitors have on sigma delta ADC?
As long as the ratio of two capacitors are fine, does the sigma delta work fine?

Thank you in advance,

 

[A.Anand Srinivasan]

Re: What are roles of capacitors in switched capacitor integ

though only the ratio counts when it comes to different capacitor values the amount of charge to charge it becomes a constraint and also the leakage value varies.....

 

[pfd001]

KT/C noise is the limit of the capacitance value