| 摘要 |
A circuit for a power amplifier amplifies and outputs an audio signal by amplifying an input audio signal using first and second differential circuits (M41,M42,M51,M52), and driving a push-pull output transistor (M60,M62). A signal generating part generates a disconnection timing signal for disconnecting a bias current reducing activation currents of the first and second differential circuits based on a switch control signal, and positive feedback loops of the first and second differential circuits. A switch part (62,64) is disposed in each of the positive feedback loops of the first and second differential circuits, disconnecting the positive feedback loops in response to the disconnection timing signal. A bias part (M45,M55) stops the operation of the first and second differential circuits by reducing the activation currents of the first and second differential circuits by reduction of the bias currents. <IMAGE>
|
