Towards a smart adaptive feedback circuit for microsensors

Integrating electronic circuits with micro-electromechanical systems (MEMS) will enable them to be smart, versatile, and potentially portable due to the intelligence of electronic circuitry, high sensitivity of MEMS device, and size of electrical components. We present a smart sensor system that utilizes a circuit's compact real-time instrumentation and readout with a MEMS resonator's high sensitivity detection of target analytes. The purpose of the feedback circuit is its integration with a developed in-plane III-V optical resonator system for chemical and biological detection. A resonator sensor utilizes the high sensitivity of cantilever's resonant frequency shift to absorbed mass. Using an integrated system, it will facilitate the testing and data acquisition by replacing multiple macro instrumentation modules. The feedback circuit is based on an optimization algorithm, which is implemented with mixed-signal design using discrete IC components on a circuit board, to track the resonant frequency of a cantilever.