If i have a Buck Regulator switching at 200KHz and i want to sample the Voltage and current using OpAmp in tha path connected to ADC(12 bit).
What would be the sampling frequency to measure the signal by ADC?
what shall be the Bandwidth of the OpAmp for Voltage and for current sense?
If somebody could provide some rule of thumb i could work further
P.S. : In my understanding sampling freq be >2 the switching freq. voltage sense would require lower BW OpAmp as it is slow, i also get confused either to choose the Opamp based on cross over freq or switching freq.