数字音频功率放大器优化设计

摘要

The component part of the digital audio amplifer is analysed in system in this paper.The technology of NBDD,dead-time and degenerative feedback is adopted to the pcmd pulse code modulation device,swithing amplifier and lower pass filter and so on.By optimizing design for pulse coding modulator,driving way,switch amplifier and low-pass filter,the distortion degree is less than 0.05%,signal-to-noise ratio is more than 110dB,the efficiency can reach 93%.%对数字音频放大器各组成环节进行了系统的分析,将双边带三电平自然采样法脉宽调制技术、Dead-Time技术、负反馈技术等引入脉冲编码调制器、开关放大器、低通滤波器等环节。通过对脉冲编码调制器、驱动方式、开关放大器、低通滤波器的优化设计,整机失真度低于0.05%,信噪比大于110 dB,效率达到了93%。