音频功放芯片中AB类输出运放的设计  

Design of Class AB Output Amplifier in Audio Power Amps

作　　者：李鸿基[1] 龚敏[1] 

机构地区：[1]四川大学微电子技术四川省重点实验室,四川成都610065

出　　处：《现代电子技术》2007年第20期192-194,共3页Modern Electronics Technique

摘　　要：采用0．6μmDPDM工艺，设计出一款在静态功耗、失调电压、输出摆幅、输出功率、THD、速度和带宽等各方面性能都比较优良的AB类CMOS输出运算放大器，其主要应用于音频功放芯片。采用推挽式功率管输出，其主体部分采用折叠式共源共栅差分电路结构，偏置部分采用外部电流源供电，并使用共源共栅电流镜结构。供电电压为3～5V，在5V下的静态功耗为6mW。能驱动32Ω耳机，其最大输出功率是90mW。仿真结果表明，电路性能优良。A class AB CMOS output amplifier with excellent performance in aspect of power consumption,offset voltage, output voltage swing, output power,THD, speed and band -width is designed using CSMC 0.6 μm DPDM process. It is mostly applied in Audio Power Amps CMOS chip. And it is built up with a pair of PMOS and NMOS push - pull output structure, principal part of a folded cascod differentia circuit structure and the bias of cascod circuit - mirror structure using exterior circuit source. The supply voltage range from 3 V to 5 V,and the power consumption is 6 mW under the supply of 5 V. It can drive 90 mW to a headphone of 32 load. The simulating performance is nice.

关 键 词：AB类 音频功放 推挽式 折叠式共源共栅 共源共栅电流镜 

分 类 号：TN41[电子电信—微电子学与固体电子学] TP33[自动化与计算机技术—计算机系统结构]