Linear comparators

Dear all,

I would like to know if there is an electrical device / circuit that can implement the following comparison function: have two ac voltage inputs (one is the reference, like comparator) and give the highest (or lowest) signal at the output: in contrast to common comparator, which outputs HIGH or LOW depending on the differential input. Could you tell me if such a device exists, or is it possible to build such a circuit?

Thanks in advance!


It’s unclear what feature of the AC waveforms mentioned you wish to compare (peak value, average value, frequency, etc.) or what the scale of the signals in question is. Converting the property of interest to a DC representation and applying these to a suitable linear comparator should yield a signal useful for controlling a DPDT relay, analog mux, or similar signal selection device.


Many thanks for your reply. I would like to compare the amplitudes of two signals, and have the signal with higher amplitude at the output (not a DC output).