Audio power amplifier with noise prevention at turn-on and turn-off

摘要

An audio power amplifier is provided that includes circuitry to prevent popping noises when the amplifier is turned on and turned off. The amplifier can be powered with a single-ended voltage power supply, and thus may be used within systems such as personal computer. The amplifier includes a control circuit that prevents the fast charging of the output AC coupling capacitor when the amplifier is turned on and turned off. The control circuit controls a driver stage such that the output transistors turn on slowly when power is first applied, and such that the output transistors turn off quickly when the supply voltage is removed.