Sunday, May 11, 2014

Piezo Buzzer

Piezo buzzer is an electronic device commonly used to produce sound. Light weight, simple construction and low price make it usable in various applications like car/truck reversing indicator, computers, call bells etc. Piezo buzzer is based on the inverse principle of piezo electricity discovered in 1880 by Jacques and Pierre Curie. It is the phenomena of generating electricity when mechanical pressure is applied to certain materials and the vice versa is also true. Such materials are called piezo electric materials. Piezo electric materials are either naturally available or manmade. Piezo ceramic is class of manmade material, which poses piezo electric effect and is widely used to make disc, the heart of piezo buzzer. When subjected to an alternating electric field they stretch or compress, in accordance with the frequency of the signal there by producing sound.


The above image shows a very commonly used piezo buzzer also called piezo transducer operating at DC voltage. Encapsulated in a cylindrical plastic coating, it has a hole on the top face for sound to propagate. A yellow metallic disc which plays an important role in the producing sound can be seen through the hole.

Piezo buzzers are small electronic devices that emit sounds when driven by low voltages and currents. They are also called piezoelectric buzzers. They usually have two electrodes and a diaphragm. The diaphragm is made from a metal plate and piezoelectric material such as a ceramic plate.


Operation
Piezo buzzers operate using the piezoelectric effect. A voltage that is applied to the leads causes the piezoelectric element to shrink or stretch. This makes the diaphragm vibrate as it bends, thereby producing sound waves. Piezo electric elements are made from crystals, such as quartz or Rochelle salts.


Sounds
The sounds emitted may be extremely low or ear-piercing. They may be made loud enough to cause hearing loss. These sounds include noises such as buzzing, chirping, ringing, sirens, and beeps.

1 comment:

  1. how can i increase the volume and how can i control the beep sound with different levels of volume
    using arduino please help me code

    ReplyDelete