A 120–330V, Sub-μA, 4-Channel Driver for Microrobotic Actuators with Wireless-Optical Power Delivery and over 99% Current Efficiency

This work presents a 4-channel, mm-scale, electrostatic and piezoelectric actuator driver that uses <; 1 μA total quiescent bias current and can drive actuator loads up to 120-330V at frequencies over 1kHz. The driver achieves over 99% current efficiency and can operate untethered with an integrated photovoltaic array driven by a collimated or diffuse optical power source. The circuit is tested with an off-chip boost circuit, generating over 1.5kV with 85% power efficiency at 45mW load. The system uses a simple 4-bit CMOS logic level interface with 100 kHz clock to actuate high voltage channels; on-chip photovoltaics also power the digital controller, and I/O bus.