A sigma-delta difference-of-squares RMS-to-DC converter and method for performing such a conversion in which a square of an analog feedback signal is combined differentially with a square of an analog input signal, thereby producing an analog product signal that includes at least one signal component corresponding to a difference between such signal squares. This analog product signal is filtered and digitized to produce a digital output signal to be available for use downstream in or with the host system, with such digital output signal also being converted to the analog feedback signal.
