I want to measure dc current by measuring the small difference in voltage across a shunt resistor. The dc has ripple (output of a full wave rectifier). Before proceeding with construction I would like to be discuss an issue that comes to my mind, that is as follows.
The sample and hold circuit of the adc would measure the amplitude of the voltage at various points in time. Since the waveform is full wave rectified dc, the adc would "catch" the waveform at different points thus giving different values for each reading.
How can I mitigate this problem.