Design of High Precision Band-Pass Sigma-Delta ADC in MEMS Gyroscope

In order to meet the demands of MEMS gyroscope for high precision and narrow bandwidth of ADC, a band-pass Sigma-Delta ADC with high precision is designed and verified by simulation. The oversampling rate (OSR) and center frequency are obtained through detecting and calculating the data of the gyroscope meter. As a result, The ADC structure of single-loop, six-order, and one-bit quantization is determined, and a suitable resonator is selected. The simulation results of the Simulink model of the ADC circuit show that the signal-to-noise ratio of the ADC can reach 132.2 dB and the effective number of bits can reach 21.70 bits, which satisfies the requirements of high precision and narrow bandwidth of the MEMS gyroscope. Thus, my design can help guide the design of transistor-level circuit for the band-pass Sigma-Delta ADC.