Audio signal output control device that suppresses pop sound

摘要

The potential of a smoothing capacitor for a speaker is smoothly changed by controlling the potential with use of a PWM signal and switching between outputting the PWM signal and an actual audio signal, thereby suppressing a pop sound. The scale of circuitry is reduced and cost is lowered by implementing a PWM circuit in a one-chip microcontroller. Noise is eliminated by outputting a pulse that has been divided in the PWM signal generation stage.