公开(公告)号：US06967530B2

公开(公告)日：2005-11-22

申请号：US10789468

申请日：2004-02-27

申请人： Jun-Ichi Omata ,  Yuji Yamanaka ,  Tomomi Oda

发明人： Jun-Ichi Omata ,  Yuji Yamanaka ,  Tomomi Oda

IPC分类号： H03F3/181 ,  H03F3/30 ,  H03F3/45 ,  H03F3/68 ,  H03F3/72 ,  H03F1/14

CPC分类号： H03F3/3022 ,  H03F3/45183 ,  H03F3/68 ,  H03F3/72 ,  H03F2200/03 ,  H03F2203/45366 ,  H03F2203/45504 ,  H03F2203/45506 ,  H03F2203/7212

摘要： A circuit for a power amplifier is disclosed which amplifies and outputs an audio signal by amplifying an input audio signal using first and second differential circuits, and driving a push-pull output transistor with the outputs from the first and second differential circuits. The circuit includes a signal generating part generating 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 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 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.

摘要翻译： 公开了一种用于功率放大器的电路，其通过使用第一和第二差分电路放大输入音频信号来放大并输出音频信号，并且利用来自第一和第二差分电路的输出来驱动推挽输出晶体管。 该电路包括产生断开定时信号的信号产生部分，用于根据开关控制信号和第一和第二差分电路的正反馈回路来断开第一和第二差分电路的减小激活电流的偏置电流。 开关部分设置在第一和第二差分电路的每个正反馈回路中，以响应断开定时信号断开正反馈回路。 偏置部分通过减少偏置电流来减小第一和第二差分电路的激活电流来停止第一和第二差分电路的操作。