Research Of High-Power Digital Class D Amplifier Based On DSP

In recent years, China's audio power amplifier industry develop rapidly, domestic production technology improve quickly. With the continuous development of digital audio technology and the demand for Hi-Fi stereo digital audio power amplifier, the development and design also has become more and more attention. Therefore, the source of digital signal processing of digital enlarge technique directly have great application prospect.This paper study the Switching power amplifier(class D) of the audio amplification field. When class D amplifiers works at switch status, transistor as control element is in low power consumption and high power amplifier efficiency which is up to 90%.So it can greatly reduce energy loss and the volume of amplifier. Class D audio power amplifier have broad prospects for development compared to traditional analog amplifier.In the first, this paper analyzes the status of the audio amplification field and introduce simply several types of audio amplifier currently on the market, prominent the advantage of Class D amplifiers. then analysis the basic principle and the topologic structure of Class D power amplifier, elicit the system research of digital Class D power amplifier. At the systemic design of digital power amplifier, This paper analyze the Novel digital former frequency-divisional processing, research a former digital FIR filter network and implement digital filtering in a digital signal processor named TMS320C5402. Take the digital audio signal into PWM modulator after the former frequency-divisional processing, implement the conversion of PCM to PWM in PWM modulation. At last, make a systemic analysis of the power output stage and low-pass filter.Finally, through the MATLAB simulation on the part of system digital filtering and audio signal power amplifier, the results show the feasibility of system and the advantage of Class D power amplifier.