The structure principle of buzzer
Structure principle 1. Piezoelectric buzzer is mainly composed of multi-vibrator, piezoelectric buzzer, impedance matching device and resonance box, shell and so on. Some piezoelectric buzzer housing is also equipped with light-emitting diodes. The multivibrator is composed of a transistor or an integrated circuit. When the power supply is connected (1.5~15V DC working voltage), the multivibrator starts to vibrate and outputs an audio signal of 1.5~2.5kHZ, and the impedance matching device drives the piezoelectric buzzer to sound. The piezoelectric buzzer is made of lead zirconate titanate or lead magnesium niobate piezoelectric ceramic material. Silver electrodes are plated on both sides of the ceramic sheet, after polarization and aging treatment, and then with yellow.