Comprehensive Harmonic Domain Simulation of a Thermally Driven MEMS Accelerometer with Full Noise Characterization

M. Szermer, J. Nazdrowicz (Lodz Univ. of Techn., Poland), M. Tuszyńska (Cracow Univ. of Techn., Poland)

This paper presents a high fidelity, harmonic domain, thermoelectromechanical simulation framework for capacitive MEMS accelerometers, integrating nonlinear mechanical dynamics, temperature dependent parameter drift, capacitive transduction, electronic readout behavior, and multi source physical noise. A complete noise synthesis module combines mechanical Brownian noise, dielectric driven capacitive noise, and electronic frontend noise, yielding realistic spectral and statistical noise characteristics. The model provides diagnostic plots covering displacement response, output voltage, noise decomposition, FFT, PSD, SNR(f), histogram statistics, NEA, and temperature induced bias drift. The simulation results are quantitatively validated against the ADXL355 commercial accelerometer, demonstrating acceptable agreement in noise density (22.6 µg/√Hz), NEA magnitude, and frequency dependent SNR, with a peak SNR of 47.8 dB under 50 Hz harmonic excitation. The proposed unified framework enables rapid design exploration, cross domain sensitivity analysis, and testing of thermal compensation strategies under realistic operating conditions.