There is disclosed a circuit and a process for detecting peak-to-peak voltage. The circuit comprises a first comparator having an output coupled to a first capacitor, a non-inverting input for receiving a high frequency AC waveform, and an inverting input, a second comparator having an output coupled to a second capacitor, and a first second input, an operational amplifier having a non-inverting input coupled to the inverting input of the first comparator, and an inverting input coupled to the first input. The process comprises charging a first capacitor when a high frequency AC waveform voltage is greater than a buffered voltage of the first capacitor, charging a second capacitor when an inverted buffered voltage of the second capacitor is greater than the high frequency AC waveform voltage, and outputting a voltage based on the buffered voltage of the first capacitor and the inverted buffered voltage of the second capacitor.