This work presents a 4-channel, mm-scale, electro-static and piezoelectric actuator driver that uses< 1 µA total quiescent bias current and can drive actuator loads up to 120-330 V at frequencies over 1kHz. The driver achieves over 99% current efficiency and can operate untethered with an integrated photovoltaic array powered by a collimated or diffuse optical power source. The circuit is demonstrated also as a driver for an off-chip boost circuit, generating over 1.5 kV 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.
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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 < 1μA 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.
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- Award ID(s):
- 1711077
- NSF-PAR ID:
- 10181246
- Date Published:
- Journal Name:
- IEEE Symposium on VLSI Circuits (VLSI)
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1109/VLSICircuits18222.2020.9162908
