3-volt high-volume buzzer

Achieving high sound intensity from a piezoelectric buzzer is not easy when the available DC power supply is only 3V. The circuit below is not only highly efficient but also produces a very loud sound. This circuit combines a boost converter and a resonant feedback network. The voltage applied to the piezoelectric crystal is approximately 40 volts peak-to-peak. The result is a circuit that produces an attention-grabbing sound without consuming a large amount of current.