3V powered headphone amplifier

The attached figure is a stereo headphone amplifier with a battery-powered +3V power supply voltage. The amplifier circuit is composed of a FET input dual op amp AD822 or AD823, which amplifies the signals of the left and right channels respectively. The operating power supply voltage range of this type of op amp is +3v---36v, and it is a full-swing op amp, which is very suitable for application at low power supply voltage.

The gain of the amplifier circuit is 2 times. The output voltage is about 2V. The output current is below 15mA. It can directly drive 32Ω headphones. The power supply current is 5mA when there is no load.