This paper presents system-level modeling and simulation of force-balance MEMS comb accelerometers. The work focuses on the theoretical principles of the sense element and the interface electronics at first. Based on that, the parametric model of the sense element is established in this paper, and the simulation results of this model match well with the theoretical results, which can prove we can use the parametric model of the sense element to establish the system-level model of force-balance MEMS comb accelerometers. The system-level model of force-balance MEMS comb accelerometers including the parametric model of the sense element and the interface electronics is established in MATLAB. The simulation results show that the designed force-balance comb accelerometer has high sensitivity, wide range, low nonlinear distortion and wide bandwidth.

This paper presents a quick system-level modeling and simulation of force-balance MEMS comb accelerometers. The derivation of the system-level model including the sense element and interface electronics is elaborated and the simulation results are obtained from COVENTOR and MATLAB respectively. The force-balance MEMS comb accelerometer, with the size of 1920 µm ´ 960 µm ´ 50 µm, the static capacitance of 2.25 pF, and the inertial mass of 5.47 µg, can endure with over load of 2000 g. Through the system-level simulation, the sensitivity is 100 mv/g, the full scale range is ± 50 g, the nonlinear distortion is smaller than 0.5 % and the system bandwidth is 2.2 kHz.

An equivalent electrical model of the MEMS comb accelerometer is presented in this paper, including the readout interface circuit. The accelerometer has only one proof mass, symmetrically suspended by four cantilevers. The displacement change of the proof mass is converted to the change of differential capacitance between the proof mass and adjacent fixed electrodes. In order to establish the mechanical characteristics of the accelerometer in this equivalent electrical model, we use the so-called analog behavioral modeling library to describe the mechanical part of the system. Through combining the electrical model of the acceleration sensor and the readout interface circuit, we get the system-level model of the MEMS comb accelerometer. The simulation results are in good accordance with theoretical analysis.