Piezoelectric buzzers and precautions for their use

Piezoelectric buzzer, mainly composed of piezoelectric sheet, PCB assembly (PCB is passive and active, active contains oscillation circuit), shell.
PCB components: epoxy copper-clad single panel, in the passive buzzer mainly play a fixed lead to connect the fixed enameled wire and the wire or pin (the wire product is directly soldered on the piezoelectric sheet to lead out), the active buzzer is more oscillation unit;
Shell: generally injection molding by ABS, PPO, LCP, PBT materials, and different temperature-resistant materials are selected according to the customer's welding method. In the buzzer, it mainly plays the role of protection and amplification of all components (piezoelectric passive product housing frequency and structural design and circuit frequency matching are extremely important).
Precautions when using piezo buzzers:
1. Do not use the buzzer in a temperature environment other than the marked working temperature (when the buzzer works outside the marked working temperature, the performance of the piezoelectric sheet and the shell changes, and the sound is small);
2. Welding according to the welding method of the logo (the usual welding methods of the buzzer are: manual welding, wave soldering, reflow soldering. Wave soldering and reflow soldering is a modern automatic welding technology, wave soldering is mainly for plug-in product welding, reflow soldering is mainly for SMD product welding, because the temperature of these two welding methods is higher, so the buzzer components must be selected temperature-resistant materials. Of course, products suitable for wave soldering and reflow soldering can also be welded by manual welding;
3. Avoid foreign objects entering the buzzer pronunciation hole (foreign matter entering the buzzer pronunciation hole may affect the vibration of the diaphragm, and the sound is small or abnormal);
4. Non-waterproof buzzer, should avoid installing the buzzer in places that may come into contact with water (non-waterproof buzzer, water will cause rust, short circuit and vibration obstruction of product parts after water enters);