Microcontroller drives piezoelectric buzzer at high voltage through one pin

摘要

A previous Design Idea demonstrates how you can use a microcontroller to drive a piezoelectric buzzer at a high alternating voltage through a four-MOSFET circuit that interfaces to two of its I/O pins (Reference 1). This expanded Design Idea provides a modi' fication of the previous circuit to save one of the I/O pins of the microcon' trailer. Q4's gate connects to Q2's drain rather than a second I/O pin (Figure 1).