Abstract: A signal detector includes, in part, first and second peak detectors, a comparator and an amplifier. The first peak detector generates a first signal in response to receiving an incoming signal. The second peak detector generates a second signal in response to receiving a threshold signal. The comparator generates an output signal representing the detected signal in response to the first and second signals. The amplifier amplifies the difference between the second signal and a reference voltage and, in response, generates a control signal that controls the gain of the first and second peak detectors. Each of the first and second peak detectors optionally include a differential amplifier and a pair of common-gate amplifiers each coupled to one of the output terminals of its associated differential amplifier. An RC network may be coupled to a common terminal of the first and second common gate amplifiers of each peak detector.