I want to detect the peak of an arbitrary amplitude sine wave. If the amplitude were fixed, I could easily construct a comparator circuit to give me a pulse output when some target voltage is reached on the sinusoid's cycle.
In my application however, the signal can vary in amplitude from a minimum of 100mV to a maximum of 3V.
How would one construct a signal conditioning circuit so that I can always have a predictable peak amplitude output for feeding into a comparator? AGC? VGA? I'm not well versed in this type of circuitry so any insight is appreciated.