D类音频功率放大器的关键技术  

Key techniques of class D audio power amplifier

作　　者：朱高峰[1] 吴黎明[1] 王桂棠[1] 张艳蕾[1] 

机构地区：[1]广东工业大学信息工程学院,广州510643

出　　处：《声学技术》2006年第5期452-456,共5页Technical Acoustics

基　　金：广东省科技计划项目(2005B10201017)

摘　　要：随着移动音频设备的迅速发展,传统的模拟线性放大器已不能满足大功率输出同时发热量少的要求,而D类放大器能克服以上缺点,但其引入的失真通常大于线性放大器,研究适合的控制方法以改善D类放大器的保真度,是近年来声学技术和音频功率放大领域研究的热点。本文除了介绍D类放大器的基本原理之外,还着重分析了几种新型的关键控制技术以及元器件选择、电磁兼容、电路板布局方面需要重视的一些问题。With the rapid development of mobile audio equipment, conventional linear amplifiers can no longer meet the requirements of large power with low heat radiation. In this respect, class D ampli-fier has good performance as a switching power amplifier. However its distortion is greater than amplifiers. New control techniques to improve fidelity of class D amplifier have been studied in recent years. In this paper, the principle of D amplifiers is presented. Some control techniques including component selection, electromagnetic compatibility, and PCB layout are discussed. Using these techniques, efficiency of 90% can be achieved, and distortion can be made below 0.5%.

关 键 词：PWM(脉冲宽度调制) THD(谐波畸变率) 单周控制 动态补偿 EMI(电磁干扰) 

分 类 号：TN72[电子电信—电路与系统]