Industry News
What is buzzer?
2015-01-05 22:04:52

A buzzer or beeper is an audio signalling device, which may be mainly electronic type (piezoelectric, electromagnetic). Typical uses of buzzers and beepers include alarm system, timers and confirmation of user input such as a mouse click or keystroke.

Buzzer plays an important part as a man-machine interface.

The buzzers which apply piezoceramics are called "Piezoelectric Buzzer", generally called “piezo buzzer”, however, the formal name is “piezoelectric sound component




Produces lower frequency tones with smaller mechanical size;

More diverse frequency range with high SPL;



Lower consumption current (save power);

Don't produce magnetic field concerns;

No pin polarity;


Electromagnetic buzzers

Electromagnetic buzzers provide low frequencies in a compact size and with higher temperature ratings, comprised of a metal diaphragm, coil, magnet, pole, and yoke. When a voltage is applied to the buzzer via the pins, a magnetic field is generated via a coil, causing the magnet to move, and the metal diaphragm to vibrate. At the metal diaphragms’ resonant frequency, air pressure waves are created that the human ear interprets as sound. Electromagnetic buzzers are dependent on the polarity of the voltage source, so to be ensured the buzzer is correctly installed into the circuit. Typically these buzzers will have either a + sign on the case or pins will be different lengths to indicate voltage input polarity. The frequency response is less defined as those distinct peaks of amplitude of piezoelectric buzzers. This allows for these buzzers to produce a more dynamic range of frequencies with strong sound pressure.


Piezoelectric Sounders

Piezoelectric sounders are piezoelectric diaphragms assembled in plastic cases (resonant cavity) and is classified into External Drive Type and Self Drive Type.
They are widely used in applications from consumer products (such as home appliances) to automotive and industrial equipment.


Active Buzzers

Active buzzer is a self drive type buzzer / beeper with built-in oscillation circuit transistor and resistors. It generates consistent single tone sound just by applying D.C.voltage.
By using a suitable designed resonant system, this type can be used with high sound pressure level.