Title :
Reducing distortion of audio class D (PWM) power amplifier by using feed-forward techniques
Author :
Zhu, Shuanghe ; Lin, Caizhang
Author_Institution :
Inst. of Telecommun. Eng., Air Force Eng. Univ., Xi´´an, China
Abstract :
The chief characteristics of an audio class D (PWM) power amplifier are higher efficiency and larger distortion that other amplifiers. This paper discusses the principle of reducing distortion for class D amplifiers by using a feed-forward error-null technique, and provides an experimental circuit. The theoretical analysis and experimental results show that the technique is effective in reducing the distortion of class D power amplifiers: the distortion has decreased from 1% to 0.1%, the output power of the amplifier is 10 watt, the efficiency is 90% and the prospect is good
Keywords :
audio-frequency amplifiers; feedforward; nonlinear distortion; power amplifiers; pulse width modulation; switching circuits; 10 W; 90 percent; AF power amplifiers; PWM power amplifier; audio power amplifier; class-D power amplifier; distortion reduction; feed-forward techniques; feedforward error-null technique; Delay effects; Feedback circuits; Feedforward systems; Frequency; Microwave circuits; Negative feedback; Nonlinear distortion; Power amplifiers; Pulse width modulation; Signal analysis;
Conference_Titel :
Circuits and Systems, 2000. IEEE APCCAS 2000. The 2000 IEEE Asia-Pacific Conference on
Conference_Location :
Tianjin
Print_ISBN :
0-7803-6253-5
DOI :
10.1109/APCCAS.2000.913580