Haptic driver for piezo with integrated 105-V boost converter in QFN package

The DRV8662 is a single-chip piezo haptic driver with integrated 105 V boost switch, integrated power diode, and integrated fully-differential amplifier. This versatile device is capable of driving both high-voltage and low-voltage piezo haptic actuators. The input signal can be either differential or single-ended. The DRV8662 supports four GPIO-controlled gains: 28.8 dB, 34.8 dB, 38.4 dB, and 40.7 dB.

The boost voltage is set using two external resistors, and the boost current limit is programmable via the R EXT resistor. The boost converter architecture will not allow the demand on the supply current to exceed the limit set by the R EXT resistor; therefore, the DRV8662 is well-suited for portable applications. This feature also allows the user to optimize the DRV8662 circuit for a given inductor based on the desired performance requirements.

A typical start-up time of 1.5 ms makes the DRV8662 an ideal piezo driver for fast haptic responses. Thermal overload protection prevents the device from being damaged when over driven.