一种二阶滤波全数字功放器的设计与实现  

Design and implementation of a two order filter full digital power amplifier

作　　者：钟卫连 杨建红[2] 王忠诚[2] 

机构地区：[1]怀化职业技术学院,湖南怀化418000 [2]怀化商业学校,湖南怀化418000

出　　处：《电声技术》2017年第6期52-55,78,共5页Audio Engineering

摘　　要：为了减小功耗,提高效率,实现电路的集成化、小巧化和贴片化,提出了一种全数字功率放大器设计方案。采用RT9107为功率芯片,再配置优质的二阶低通滤波器,就能构成高性能的双声道全数字功率放大器。该功放器采用I2S总线输入,PWM信号输出方式,不但具有元件少,体积小的特点,而且还实现了音频信号的全数字处理。实践表明,此功率放大器的最大输出功率可达2×18 W,总谐波失真度加噪声(THD+N)在3%以下,电路效率可达90%以上,频率响应可达20 Hz^20 k Hz。In order to reduce power consumption,improve efficiency and realize the integration, compact and SMD of the circuit,a scheme of all digital power amplifier has been proposed. The RT9107 is used as the power chip, with configuring high-quality two order low-pass filter,can constitute a double channel high performance digital power amplifier. The power amplifier using I^2S bus input and PWM signal output, not only has less components, small volume features, but also to achieve a full digital audio signal processingo The practice shows that the power amplifier output power can be up to 2 × 18 W,Total Harmonic Distortion ＋ Noise （THD ＋ N）under 3% , Circuit efficiency up to 90% , Frequency response up to 20Hz 20kHz.

关 键 词：数字功放 RT9107 PWM信号 I^2S总线 I^2C总线 二阶滤波 

分 类 号：TN722.5[电子电信—电路与系统]