带啸叫检测与抑制功能的音频功率放大器的设计

摘要

The design is based on ampliifer chip TPA3112D1,and the MAX262 is used to design and produce an audio ampliifer with the function of howling detection and suppression to achieve the detection of whistle signals and suppression.The system consists of six modules:pick up circuit module,pre-ampliifer module,howling detection module,howling suppression modules,power ampliifer modules and power modules.This system is characterized by the largest real-time monitoring module whistle howling detection frequencies,programmable iflters through the microcontrol er chip MAX262 howling suppression modules designed to realize the band-stop iflter speech signal processing,and is able to iflter characteristic parameters,such as the center frequency,quality factor and other programmable settings to reduce the complexity of the external circuit.%本设计基于TPA3112—DEMO板，利用MAX262设计并制作一个带啸叫检测与抑制功能的音频放大器，实现了对啸叫信号的检测与抑制功能。系统主要分为六个模块：拾音电路模块、前级放大模块、啸叫检测模块、啸叫抑制模块、功率放大电路模块以及电源模块。系统最大特点是由啸叫检测模块实时监测啸叫频率点，通过单片机控制由可编程滤波器芯片MAX262设计的啸叫抑制模块，实现对语音信号的带阻滤波处理，并能对滤波的特性参数如中心频率、品质因数等进行可编程设置，减少了外围电路的复杂度。