Improved Interface Circuits for CMUT Chemical Sensors

Capacitive Micromachined Ultrasonic Transducer (CMUT) chemical sensors have demonstrated outstanding sensitivity for chemical sensing in air. In order to achieve good low limit of detection and good sensor reliability, attention must be paid to the interface circuits. In this work, we demonstrate how a transistor-based oscillator circuit can be used to achieve low noise, small size and low power consumption for CMUT chemical sensor arrays. We show how to optimize these circuits, and show how they can be enabled and disabled to allow multiplexing in time.