Silicon substrate differential motion quartz acceleration sensor

Abstract

A silicon substrate differential motion quartz acceleration sensor comprises two silicon substrates which are installed in the opposite directions and two-end-fixed quartz tuning forks, the silicon substrates are clamped between an upper overload protection plate and a lower overload protection plate, a structure formed by the silicon substrates, the two-end-fixed quartz tuning forks, the upper overload protection plate and the lower overload protection plate is placed in a hole of a circuit board, the two-end-fixed quartz tuning forks penetrate through through holes of the upper overload protection plate and are connected to the circuit board through gold wires, an inverse piezoelectric effect exists in the two-end-fixed quartz tuning forks, a circuit is adopted to inspire vibration, when acceleration acts on mass blocks supported by flexibility silicon beams, a differential motion structure is formed by the two two-end-fixed quartz tuning forks, and an output signal of the sensor is the difference of the frequency of the two two-end-fixed quartz tuning forks. When the temperature changes, the two two-end-fixed quartz tuning forks are pulled or pressed simultaneously, frequency changes are identical, the temperature affect can be offset through the subtraction of the frequency changes, the silicon substrate differential motion quartz acceleration sensor has the advantages of being small in size, light in weight and high in digital signal output and resolution ratio.

Description

technical field [0001] The invention belongs to the technical field of micro-mechanical electronics, and in particular relates to a silicon-based differential quartz acceleration sensor. Background technique [0002] High-precision digital navigation systems have been widely used in aircraft, missiles, and underwater driving. As an important part of the digital navigation system, the acceleration sensor with frequency output characteristics has more and more strict requirements on its high precision and high resolution. The output of this type of accelerometer is a frequency signal without the loss of accuracy caused by digital-to-analog conversion. Sensors in this area mainly include silicon microresonant sensors and quartz resonant acceleration sensors. The processing technology of silicon microresonant sensor based on MEMS is complex and the resolution is low. Such acceleration sensors generally use electrostatic excitation, and the design of the excitation structure i...

AI Technical Summary

Problems solved by technology

The first type has a compact structure, the sensor is small in size, but there is a self-locking phenomenon, and there is no overload protection structure

The foundation of the second type is generally processed by traditional technology, the material is mostly metal, the dimensional stability is not high, and the sensor is bulky

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