Fully integrated piezo driver for haptic feedback
The DRV8662RGPT: It drives capacitive piezo actuators from a 3V to 5.5V supply rail, generating output voltages from 20V up to 200V — the range covers everything from smartphone button clickers to industrial touch-feedback panels. The 75mA output current capability is enough to charge and discharge the piezo element quickly for crisp haptic pulses, but the actual slew rate and peak force depend on the load capacitance.
Control interface and output stage
The DRV8662RGPT accepts both analog and PWM input signals, so it can be driven directly from a microcontroller's DAC output or a timer PWM pin without an external level shifter. The differential output configuration drives the piezo element with a bipolar waveform, which doubles the effective voltage swing across the actuator compared to a single-ended drive — useful for maximizing displacement from a given supply voltage. The integrated power MOSFET stage handles the high-voltage switching, and the 20-QFN package with exposed pad (4x4 mm) provides a thermal path to the PCB copper pour for heat dissipation.
Temperature range and environment
The surface-mount 20-VFQFN package with exposed pad requires a proper solder stencil design and reflow profile for the center thermal pad to achieve the rated thermal performance.