Structural Analysis And Circuit Design Of MEMS High-g Piezoresistive Accelerameter

MEMS high-g piezoresistive accelerometer is widely used in impact testing,explosion,fuze and other field,it is indispensable measurement devices for the missile penetration,impact test and other experiment.Because MEMS high-g piezoresistive accelerometer often apply in poor environment,so MEMS high-g accelerometer should have high range,relatively wide bandwidth and good reliability.Researching and developing high-performance high-g accelerometers has important strategic significance in enhancing the national defense strength and breaking the foreign blockade.The paper based on MEMS high-g piezoresistive accelerometer,its main contents are as follows:(1)The piezoresistive effect is deeply studied,and the high-g piezoresistive accelerometer is discussed,which mainly includes the structure,working principle,processing technology and packaging.(2)The dynamic characteristics of MEMS high-g piezoresistive accelerometer are analyzed theoretically.The high-g piezoresistive accelerometer is equivalent to the spring-damping-mass system,and the natural frequency of the system and the air damping is analyzed deeply.The damping ratio calculation formula is derived,and the damping ratio of the influencing factors is analyzed.(3)The finite element simulation of ANSYS software is used for the MEMS piezoresistive accelerometer,the accelerometer material character is analyzed deeply,and the finite element model is established,and the static simulation is carried out.The vibration model of the accelerometer is analyzed by modal simulation,and the harmonic response analysis and transient dynamic simulation analysis are carried out to verify the rationality of the structure.The influence of wet etching on the structure of the accelerometer was analyzed by transient dynamic simulation.The position of the varistor is determined and the output voltage and acceleration of the sensor are established through MATLAB,and the sensitivity is analyzed.(4)The external conditioning circuit of MEMS high-g accelerameter was designed,and the zero output test were carried out.