A phase comparator suitable for integrated circuit fabrication is disclosed wherein each one of a pair of differential amplifiers periodically couples an input signal to the output of the comparator through a degenerative feedback arranged high gain amplifier selectively in accordance with a periodic reference signal. During one-half period of the reference signal, the input signal is coupled to the output of the comparator with a gain of substantially +1 and during the other half period of the reference signal the input signal is coupled to the output of the comparator with a gain of substantially -1. With such an arrangement the output voltage produced at the output of the phase comparator has an average value substantially proportional to the phase angle between the reference signal and the input signal. The use of a switched pair of differential amplifiers together with a degenerative feedback arranged high gain amplifier provides for a phase comparator suitable for integrated circuit fabrication.