Piezoceramic Buzzers
In order to increase sound pressure and obtain beautiful sound, the piezo element is usually enclosed into a resonance chamber to form a piezoelectric ceramic buzzer. The piezoelectric ceramic buzzer is widely used in articles for daily use, office/home automation apparatus, instruments and meters for detection, communications, and alarming devices, including toys, clocks and watches, telephones, fax machines, microwave ovens, multimeters, mobile phones, foggers, theft-proof locks, and etc.   1. Node support
2.End support
	fo: Resonant Frequency       t: Thickness       r: Radius of metal plate       E: Yong's modulus       P: Density       G: Poisson's ratio
Characteristics: high sound pressure, excellent sound quality, free of spark, low power, long lifetime.

Piezo Buzzer (External Drive Type)

Piezo Indicator (Built-in Circuit)