Classification of buzzer:
1. According to the principle of driving mode, it can be divided into active buzzer (including driving circuit) and passive buzzer (external drive);
2, according to the different construction methods, it can be divided into electromagnetic buzzer and piezoelectric buzzer;
3. According to the different packaging, it can be divided into: DIPBUZZER (needle insertion buzzer) and SMDBUZZER (patch buzzer);
4. According to the different electric current, it can be divided into DC buzzer and AC buzzer. Among them, DC is the most common piezoelectric buzzer, which uses piezoelectric material, that is, when the piezoelectric material is deformed due to external force, the piezoelectric material will generate electric charge. Similarly, when electrified, the piezoelectric material will deform.
Electromagnetic buzzer is mainly used to make use of the characteristics of magnetic field produced by electrified conductor. It uses a fixed permanent magnet and electrified conductor to produce magnetic force to push the drum fixed on the coil.
Due to the different pronunciation principles of the two buzzers, the piezoelectric structure is simple and durable, but the tone is single, and it is suitable for alarms and other equipment. The electromagnetic type is used for voice, music and other equipment because of its good timbre.