A New Structure for a CMOS Audio Power AMP with Extremely Low THD and Low Power Consumption

一种新型的超低THD,低功耗CMOS音频功率放大器(英文)

A new system-corrected CMOS audio power AMP is presented. Consisting of four single-end OPAs,this structure is a pseudo-differential system. Compared to conventional CMOS power AMPs, it has the merits of low power consumption, extremely low THD,easy compensation, and good driving capability. With 1st silicon 0.25μm 1P4M CMOS technology and a 3V power supply,the output range can be 4Vpp when driving an 8Ω‖ 300pF load, while its power dissipation is less than 3mW. The THD is better than 0. 003% at 1kHz. A new over-current protection circuit, which can effectively protect the power output circuits on the chip, is also demonstrated.

提出了一种新型的系统矫正结构CMOS音频功率放大器.该放大器是由4个单端运放组成的伪差分结构.相对于传统的CMOS功率放大器,它具有低功耗、超低THD、易于补偿、驱动能力强等优点.采用1stsilicon0.25μm1P4M工艺制备,在3V电源电压下,驱动8Ω‖300pF的负载,其输出摆幅可以达到4Vpp,静态功耗小于3mW.在1kHz的正弦波激励下,其THD小于0.003%.还提出了一种新型的过流保护电路,可以对片内大功率输出级电路进行有效的保护.