User:ReggiKunz697
From LVSKB
The piezo buzzer use piezoelectric ceramic piezoelectric effect to drive the vibration of the metal to make voice. Electromagnetic buzzer use the principle of electromagnetic,metal diaphragm will be sucked under power .while under no power,it use the elasticity of diaphragm to rebound, so the piezo buzzer use the square wave to drive, electromagnetic is 1/2 square wave driver.