一种低功耗多模式AB类音频放大器的设计  

Design of a Low Power Multi-Mode Class AB Audio Amplifier

作　　者：徐凯英 丁宁 孔祥艺 黄立朝 XU Kaiying;DING Ning;KONG Xiangyi;HUANG Lichao(China Electronics Technology Group Corporation No.58 Research Institute,Wuxi 214035,China)

机构地区：[1]中国电子科技集团公司第五十八研究所,江苏无锡214035

出　　处：《电子与封装》2022年第11期48-51,共4页Electronics & Packaging

摘　　要：音频放大器需要兼容耳机和扬声器2种模式,当AB类音频放大器工作在耳机模式时,主运放关断,仅使用从运放驱动耳机负载,可有效降低放大器的功耗。改进后的AB类音频放大器扬声器模式输出功率为3 W,耳机模式静态功耗为32.5 m W,全模式总谐波失真(THD)为0.02%,失真率低、音效品质高。芯片新增了过流保护模块,能够适应不同的负载环境,在小型电子设备中具有良好的应用前景。An audio amplifier needs to be compatible with both headphone and speaker modes. When a class AB audio amplifier is in the headphone mode, the main operational amplifier is switched off, only the slave operational amplifier drives the headphone load, and the power consumption of the amplifier can be significantly decreased. The improved class AB audio amplifier has a speaker mode output power of 3 W, a static power consumption of 32.5 m W in the headphone mode, and a total harmonic distortion(THD) of 0.02%in the two modes. The audio amplifier has low distortion rate and high quality sound. The over-current protect circuit is added to protect the chip in different load conditions, and the chip can be widely used in small electronic devices.

关 键 词：AB类音频放大器 多模式 低功耗 过流保护 低失真 

分 类 号：TN433[电子电信—微电子学与固体电子学]