Optimizing frequency compensation in chopper offset-stabilized amplifiers with symmetrical RC notch filters

The paper presents three approaches for frequency compensation in chopper offset-stabilized amplifiers with symmetrical passive RC notch filter with two cutoff frequencies. The filter has two cutoff frequencies: the chopping frequency itself and the fifth harmonic of the chopping frequency. The frequency compensation network is connected either at the input of the notch filter, or at its output, or between its two sections. The large signal transient response is evaluated in terms of the overshoot/undershoot and the settling time. Three circuits using these techniques were fabricated and evaluated. The approach that uses the frequency compensation network connected between the sections of the filter has the best results, except for the chopping ripple rejection.