Capacitance-to-Voltage Electronic Front Ends for MEMS Capacitive Accelerometer: A Review

This paper presents a comprehensive review of the capacitance to voltage (C/V) electronic front-end topology for the Micro-Electro-Mechanical Systems (MEMS) capacitive accelerometers. The C/V front-ends can be roughly classified into continuous-time C/V converter and discrete-time C/V converter, which are further divided into four types: continuous-time voltage-mode (CT-VM) C/V converter, continuous-time current-mode (CT-CM) C/V converter, discrete-time voltage-control (DT-VC) C/V converter and discrete-time charge-control (DT-CC) C/V converter. The features of different C/V converters and the essential design equations are presented to provide the designer with guidelines for choosing the most suitable topology. Besides, the trade-off relationships among C/V converter’s performance are illustrated, and the primary non-ideal characteristics that exist in C/V converter, such as gain error, offset, noise, non-linearity and charge injection are analyzed. The different assistant techniques for C/V converter are given to address these non-ideal problems, and the C/V front-ends can not only achieve low process sensitivity and high resolution but also obtain low power consumption and high-power efficiency.