AN2282 - Analog - Resonant Bridge Oscillators for Piezoelectric Buzzers

This Application Note shows an example of a piezoelectric resonator with an excitation throughout its frequency range using the PSoC® 1 device. This technique allows the user to obtain the maximum output power for a given supply voltage. The oscillators have no CPU overhead during operation.

개요

Piezoelectric buzzers are widely used in various embedded systems including alarm systems, vending machines, kiosks, access control devices, entertainment systems, home appliances, and medical equipment. In most cases, only a 3.0- to 5.0-volt supply is available, which makes it more difficult to obtain a loud audio signal because piezoelectric materials usually require higher operating voltages. Combining a bridge buzzer together with resonant frequency excitation renders higher power supply voltage usage and increases the generated sound pressure level.