MUTE DETECTING CIRCUIT

PURPOSE:To provide a mute detection circuit having a click sound eliminated at the time of muting an audio output signal. CONSTITUTION:A comparator 2 which compares an audio output signal 1 with a prescribed reference voltage, a mute signal generating circuit 5 which generates a mute start command and a mute release command, and a controller 3 which controls the timing of muting are provided. When the mute start command is outputted from the mute signal generating circuit 5, the controller 3 waits for muting. Muting is applied by the output of the comparator at the time when the DC voltage component of the audio output signal 1 is eliminated, and thereby, the variation of the DC voltage component is reduced to eliminate the click sound.