A Method for Improving Shock Vibration Performance of Silicon Microresonant Accelerometer

Abstract

The invention discloses a method for improving the shock vibration performance of a silicon micro-resonance accelerometer, comprising a silicon micro-resonance accelerometer, a differential detection comb, a front-end reading circuit, a damping control circuit, a signal coupling circuit and a push-pull driving comb. The method senses the displacement of the mass block through a differential detection comb connected to the mass block and a front-end reading circuit, and acts on the damping control circuit, and the generated control signal acts on the push-pull driving comb through the signal coupling circuit and drives the comb to the mass block. produce electrostatic force. The present invention utilizes integral negative feedback to realize the amplitude-frequency characteristic of the damping control circuit in which the amplitude increases linearly with the frequency in the system bandwidth range, constructs the attenuation characteristic of the amplitude in the high frequency band, and can suppress the circuit noise by adjusting the turning point of the amplitude-frequency characteristic of the damping control circuit; The damping control circuit constitutes a negative feedback control to effectively improve the system damping, reduce the excitation response of the mass block resonance mode, and improve the shock and vibration performance of the silicon micro-resonance accelerometer.

Description

technical field [0001] The invention belongs to the technical field of micro-electromechanical systems (MEMS) and micro-inertia, relates to a silicon micro-resonance accelerometer, in particular to a method for improving the shock vibration performance of a silicon micro-resonance accelerometer. Background technique [0002] Silicon micro accelerometer is a micro-mechanical inertial device developed based on MEMS (Micro Electromechanical system) technology. Compared with traditional inertial sensors, MEMS devices manufactured by micro-machining technology and integrated circuit (IC) technology have volume It has the advantages of small size, light weight, low power consumption, high integration, easy realization of intelligence, and mass production, and has been widely used in civilian and military fields. [0003] As a kind of micro-electromechanical accelerometer, the silicon micro-resonant accelerometer is sensitive to the magnitude of the acceleration by detecting the ch...

AI Technical Summary

Problems solved by technology

When the silicon microresonant accelerometer works in a mechanical environment with random vibration and short-term impact signals, its resonant modal response will be more easily excited and have a larger response amplitude due to the high Q value characteristics of the mass block And longer decay time, which reduces the response and recovery ability of the silicon microresonant accelerometer in the shock vibration environment, affecting the shock vibration performance of the silicon microresonant accelerometer

In view of the above problems, in the application of capacitive micromachined accelerometers of silicon microaccelerometers, a solution often used is to introduce a PD controller to form a negative feedback control to improve the damping coefficient of the mass block, but the differential control term in the PD controller It has extremely high sensitivity to high-frequency signals, making the controller very sensitive to high-frequency noise signals, increasing the output noise level of the controller, thereby introducing unnecessary loop noise to the silicon micro-accelerometer and reducing the resolution of the system

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