System Design of Nonideal Fourth-Order Sigma-Delta Micromachined Accelerometer

摘要

The paper describes the system design for a nonideal capacitive micromichined accelerometer in MATLAB/SIMULINK. In this paper, a fourth-order sigma-delta micromachined accelerometer system design is represented, which includes the electrode movement and circuit noise. By simulation and comparison with the ideal 4th-order sigma-delta accelerometer in MATLAB, we have found that the SNR is essentially influenced by the electrode movement. Moreover the influence of the electrode stiffness K_e is researched. We have also researched the effects of the kT/C noise and the front-end amplifier noise. This nonideal accelerometer system can represent more accurate simulation result.