Inertial sensor capacitance detection accelerometer

Abstract

The present invention provides an inertial sensor capacitance detection accelerometer. The input end of a preamplifier is connected with the signal output of an inertial detection element; the input end of an instant floating point analog-to-digital converter is connected with the output signal of the preamplifier; the output digital signals of the instant floating point analog-to-digital converter are transmitted to a digital loop filter, and then a one-digit quantizer outputs digital stream; and the digital stream passes an electrostatic force feedback unit to realize the closed loop operation. The negative feedback is realized through adoption of a sampling technology, and the linearity and the dynamic precision of the closed loop system are improved. The digital loop filter is employed to realize the shaping of quantification noise to reach the purpose of low noise and digital quantity output. Through adoption of a digital mode, the loop filter is able to avoid the integration saturation phenomenon generated by the simulation of the loop filter and reduce the layout design difficulty and the influence of the noise of simulation of the loop filter on the system. Through adoption of the instant floating point analog-to-digital converter, the inertial sensor capacitance detection accelerometer performs quantification to effectively improve the system noise performance.

Description

technical field [0001] The invention belongs to the technical field of inertial sensor detection, and in particular relates to an inertial sensor capacitance detection accelerometer. Background technique [0002] Inertial sensors generally include sensitive devices such as accelerometers and gyroscopes. When these inertial devices are affected by external forces, they will produce corresponding movements. It is necessary to measure the speed and acceleration of the sensor relative to the reference object. Take the MEMS (Micro-Electro-MechanicalSystem) accelerometer as an example. Compared with traditional acceleration detectors, MEMS accelerometers have the advantages of small size, low cost, high sensitivity, and easy integration. At the same time, they have the advantages of large dynamic range, good linearity, and high bandwidth during closed-loop operation, which makes their application scope more and more Extensive, such as in automobiles, smart phones, drilling explor...

AI Technical Summary

Problems solved by technology

Although the use of high-precision ADC reduces the quantization noise, the effective number of bits actually used in the closed loop is very

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