How to choose SMD buzzer?

SMD buzzer has a wide variety of different specifications. We need to know several main parameters (voltage, current, drive development mode, size, fixed working mode of connection). Of course, more importantly, the sound we want to obtain (sound pressure level, frequency level).
working voltage: electromagnetic buzzer, from 1.5 to 24V, piezoelectric from 3V to 220V are feasible, but the general piezoelectric or recommended more than 9V voltage, in order to obtain a larger sound.
Current consumption: The electromagnetic type depends on the voltage, from tens of milliamperes to hundreds of milliamperes. The piezoelectric type saves more power and can work normally with a few milliamperes. When the buzzer is started, it consumes three times the current immediately. about.
Driver: Both buzzers are self-excited. They can sound as long as they are connected to direct current (DC), because the drive circuit has been built in the buzzer. Because of the different operation principles, the electromagnetic buzzer needs to be driven by 1/2 square wave, while the piezoelectric buzzer needs to use square wave to have better sound output.
Size: Its size will affect the size of the control volume, the level of the frequency, the electromagnetic type is smaller from 7mm to the larger 25mm, and the piezoelectric type is developed from 12mm to 50mm or more.
Connection mode: Generally, there are pins, welding wires, patches, piezoelectric large ones and locking screws.
Sound Pressure: A distance of 10cm is usually used as the test standard. If the distance is doubled, it will attenuate by about 6dB. On the contrary, if the distance is doubled, it will increase by 6dB. The electromagnetic buzzer can reach the level of 85dB/10cm. The piezoelectric buzzer can be made very loud. Most common alarms are made of piezoelectric buzzers.
The above is the introduction of this small series SMD buzzer how to buy knowledge, I hope it can help you.