Miniature piezoelectric buzzer

摘要

The buzzor includes a flat cylindrical box (10) made of synthetic material, and a sound generator comprising a piezoelectric disc-shaped element (20) linked to the underside of a thin elastic disc (22). The piezoelectric element has a conductive layer formed on it by evaporation, and this is divided into an excitation electrode and a counter-electrode. These electrodes are connected to an oscillator circuit (16). Some of the components of the oscillator circuit may be formed on the same conductive layer which constitutes electrodes, the components being formed at the nodes of the oscillation which the disc undergoes.