›› 2012, Vol. 25 ›› Issue (5): 17-.

• 论文 • 上一篇    下一篇

基于ΣΔ调制的D类放大器系统设计与仿真

高爱国   

  1. (中国人民解放军92853部队 4分队,辽宁 葫芦岛 125106)
  • 出版日期:2012-05-15 发布日期:2012-05-24
  • 作者简介:高爱国(1984—),男,硕士,助理工程师。研究方向:通信信号处理。

System Design and Simulation of Class D Amplifier Using ΣΔ Modulator

 GAO Ai-Guo   

  1. (Fourth Divisions,Unit 92853,PLA,Huludao 125106,China)
  • Online:2012-05-15 Published:2012-05-24

摘要:

针对传统D类放大器脉宽调制技术引起的电磁干扰问题,将一个5阶低通ΣΔ调制器应用于一种带反馈闭环结构的D类放大器中。通过建立ΣΔ调制D类放大器的非理想模型,考察输出信号的功率谱特性。仿真分析表明,该模型能够有效抑制低频段的噪声和谐波失真,在基带内实现较高的信噪比,应用于D类功放,与传统脉宽调制方式相比,有效地改善电磁干扰性能。

关键词: D类放大器, &Sigma, &Delta, 调制, 电磁干扰, 功率谱密度

Abstract:

In view of the fact that pulse width modulation may cause electromagnetic interference (EMI) in Class D Amplifier,this article applies a five-order low pass Σ Δ modulator to A class D amplifier with a feedback loop structure.The output signal spectrum properties are studied by establishing a nonideal model of class D amplifier.Simulation results show that this model can reduce the noise and harmonic distortion in low frequency band,achieve higher signal-to-noise ratio in baseband.Its application in the class D amplifiers can improve the electromagnetic interference performance effectively compared with traditional pulse width modulation.

Key words: class D amplifier;Σ&Delta, modulation;EMI;power spectrum density

中图分类号: 

  • TN722.7