Differences Between Passive Buzzer and Active Buzzer

How to distinguish passive buzzer and active buzzer?

There are several ways to distinguish passive buzzer and active buzzer.

1. The most simple method is to watch their different appearances.If you can see a drive board,it is passive buzzer.If the buzzer is completely covered by black adhesive,it is active buzzer.

2. Another method. Using an battery with a piece of electric wire,seperately touch the connection terminals of buzzer.If the buzzer makes sound like "Chi" in every touch,it is passive buzzer. If it just makes sound for one time or soundless, it is active buzzer.

3. Controllable sound is one feature of passive buzzer.It can make sound in different frequences.However,it must be drived by square wave and then will make sound.

   While active buzzer don't need square wave,it will make sound at the time being offered DC power. That's because there is oscillator in active buzzer while no osillator in passive buzzer.

4. Most passive buzzers has small size. In the market,there are more pasive buzzers than active buzzers. Active buzzer is more expensive than passive buzzer.