驻极体传声器(MIC)是一种把声信号转换成电信号的器件。常用于宣传广播、文艺演出、大型演讲及家庭影院等场合。一、基本结构驻极体式传声器的内部结构如图1所示。它的振膜前表面与外壳相连,振膜内侧与金属背极间设置一层绝缘衬圈,因振膜镀有一层金属膜,使振膜前表面与金属背极间形成电容。由于振膜自身带有极化电荷,两极间即有一定电压,当声波使振膜振动时,两极间距离改变,从而产生随声波变化的交变电压信号。二、连接方式驻极体式传声器与应用电路的连接方式有两种,如图2所示。源极输出方式需三根引出线。漏极D接 An electret microphone (MIC) is a device that converts acoustic signals into electrical signals. Commonly used in publicity radio, theatrical performances, major lectures and home theater and other occasions. First, the basic structure of the electret microphone’s internal structure shown in Figure 1. The front surface of the diaphragm is connected with the shell. An insulating ring is arranged between the inner side of the diaphragm and the metal back. Because the diaphragm is coated with a layer of metal film, a capacitance is formed between the front surface of the diaphragm and the metal back. As the diaphragm itself with a polarized charge, that is, there is a certain voltage between the two poles, when the sound wave so that the diaphragm vibration, the distance between the poles change, resulting in alternating voltage signal with the sound wave changes. Second, the connection electret microphones and application circuit connection in two ways, as shown in Figure 2. Source output mode requires three leads. Drain D then