A high bandwidth, high voltage amplifier for driving fast piezoelectric actuator-based nanopositioners used in atomic force microscopes

Abstract

Some of the challenges of adapting high-voltage amplifier (HVA) designs and solutions for driving highly capacitive loads such as piezoelectric actuators (PEAs) fast include cost, implementation complexity, management of thermal load, and difficult customization. In this work, we develop an easy to implement HVA with 525 kHz small signal bandwidth, 6 App , and 110 Vpp HVA using a low-cost high voltage operational amplifier (HV-OPA) and a self-biasing power amplifier (PA). At 100 kHz, the phase lag is about -24∘ and the HVA can be configured for use with or without the PA stage to prioritize input tracking and output noise reduction or output stability improvement. When used to drive our custom high-speed atomic force microscope (HS-AFM) Z-scanner during imaging, compared to a conventional commercial HVA, our custom HVA is able to track topographical features at faster scan speeds.