Headphone stereo control circuit

Abstract

A headphone stereo control circuit includes a pre-power amplifier IC 1 wherein a motor speed control circuit 2, a motor driving transistor 3, a pre-amplifier 4 and a main amplifier 5 are mounted. In the headphone stereo control circuit, a headphone motor 6 is connected to the motor output pin P1of the motor driving transistor 3; a stereo head to the stereo head input pin P2 of the pre-amplifier 4; a tuner circuit 8 to the tuner input pin P3 of the main amplifier 5; and a speaker 9 to the main amplifier output pin P4 of the main amplifier 5. Further, a pin P8 for common use in effecting pre-amplifier.speed control is provided, the pin for common use being capable of applying supply voltage simultaneously to the motor speed control circuit 2 and the pre-amplifier 4, so that the supply voltage is supplied via a single-pole change-over switch 12 to the pin P8 for common use in effecting pre-amplifier.speed control.

Dependencies are inferred from the claim text.