Analysis of Circuit Noise in Integral Electronics Piezoelectric Accelerometer

Integral electronics piezoelectric (IEPE) accelerometers are the vibration acceleration sensors using piezoelectric effect. Analyze the main noise sources of IEPE accelerometer circuit. With the noise model of E-n - I-n the internal noise is equivalent to input, realizing the direct comparison of the input noise and signal, and easily getting the noise effect on the signal. Propose the transformation principle of Y - Delta to the T network noise analysis to reduce the difficulty of the noise analysis. Deduce the formula of the circuit background noise in IEPE accelerometer in the broadband. The comparison of noise analysis values of theoretical and obtained by PSpice software proves a good correlation and shows the correctness and effectiveness of the formulas. Meanwhile, put forward the methods of total noise reduction in different frequencies based on the deduced noise formula of the contributions of various noise sources at the input to the total noise. The studies provide a theoretical basis for IEPE accelerometer circuit design in low noise, parameter selection and performance optimization.