In order to further depress noise in signal bandwidth

a fifth-order MEMS accelerometer closed-loop control system based on Sigma-Delta modulator（∑-△M） with multi-feedback loops and resonators（MFLR） is proposed

this system through adding additional local feedback to shape the quantization noise structure of MEMS accelerometer is fully differential structure which is manufactured on SOI wafer with structure layer thickness of60 μm and substrate layer thickness of 400 μm

manufacturing procedure includes lithography

sputtering

deep reactive ion etching

etc.Matlab/Simulink model of overall closed-loop control system

is firstly set up

then

system parameters are set by unit circle analysis method.System simulation show that power spectral density（PSD）simulation of the system is derived.The amplitude of input is 1 g

and frequency of signal is 128 Hz

noise is—136.2 dB which is 7.9 dB lower than traditional 5 th-order closed-loop control system based on ∑-△M with MF topology

at range signal bandwidth of 0

5

00 Hz.A four-layer printed circuit board（PCB） prototype of this system is built to validate functionality of the system and tested.