FAN8831: Sinusoidal Piezoelectric Actuator Driver with Step-Up DC-DC Converter

The FAN8831 is a single-chip piezoelectric actuator driver consisting of step-up DC-DC converter with integrated 36 V boost switch and a full-bridge output stage. The device is capable of driving a Piezo bi-directionally at 120 V peak to peak from a single 3 V lithium cell. The step-up DC-DC converter operates in critical conduction mode (CRM) and is optimized to work in a coupled inductor configuration to provide output voltages in excess of 60 V. Over-voltage protection, over -current protection, and thermal shutdown are all provided. An internal ready is used to enable the full-bridge gate driver when step-up DC-DC converter output voltage reaches the proper level with hysteresis. The boost voltage is set using external resistors, and step-up current limit is programmable via the external resistor at OCP pin. The output H-bridge features four integrated 75 V P and N-channel for sine wave drive of the Piezo actuator.

Features

• Step-Up DC-DC Converter
• Integrated Step-up Power Switch up to 36 V
• Wide Operating Voltage Range of 2.7 to 5.5 V
• Adjustable Step-up Output Voltage
• Adjustable Step-up Current Limit
• Zero Current Detector (ZCD)
• Internal Soft-Start
• Built-in Protection Circuit
  • Over Voltage Protection (OVP)
  • Thermal Shutdown (TSD)
• Over Voltage Protection (OVP)
• Thermal Shutdown (TSD)
• Piezo Actuator Driver
• Integrated Full-Bridge Switches (V_DS=75 V)
• Digitally implemented Sine Modulator
• Package Information
• Small 4.0 mm × 4.0 mm MLP

Application Notes