The Study Of Measurement System Of Diffusion Silicon Pressure Sensor

In this paper,piezoresistive pressure sensor measurement system has been studied in depth,including the following aspects:?1?Analysis of piezoresistive pressure sensor working principle,and the temperature sensor as an auxiliary sensor for two-dimensional temperature calibration experiment,confirmed its existence of temperature drift phenomenon,the actual use of certain measures must be taken to solve this problem,in order to ensure that it has a stable measurement performance.?2?This text has designed a constant current source based on TL431,this constant current source has very good stability,can guarantee steady supply of the piezoresistive pressure sensor.In order to solve the shortcoming of the piezoresistive pressure sensor's input and output nonlinearity,this paper uses the curve fitting method to do the non-linear correction.The experimental results show that the linearity of the piezoresistive pressure sensor is greatly improved.?3?In this paper,the software algorithm is used to solve the temperature drift problem of piezoresistive pressure sensor.To solve this problem,a data fusion model based on differential evolution algorithm?DE?to optimize BP neural network algorithm is established.DE ensures that the optimization algorithm searches for the best in the global scope Solution,solve the BP easy to fall into the local minimum defects.The data fusion of the piezoresistive pressure sensor with this model shows that the temperature coefficient of sensitivity decreases from 1.88×10^-3 to1.98×10^-4,and the relative error of the temperature additional error decreases from 9.6%To0.912%.The experimental results show that the DE-BP model can effectively improve the temperature drift of the piezoresistive pressure sensor.?4?At the end of this paper,a complete intelligent pressure measurement system is designed.The DE-BP model is used internally for temperature compensation,which greatly improves the stability of the measurement results.The system design includes hardware part and software part.The hardware part of the STM32F103 microcontroller as the core processor,designed signal acquisition circuit,amplifier,A/D converter module,alarm circuit,serial communication circuit,and LCD display module.The software part includes the core temperature compensation algorithm,as well as various module subroutines.After the overall design of the system is completed,the software and hardware are jointly debugged and continuously optimized,and then the overall performance of the system is tested in a practical test.The experimental results show that the intelligent pressure measurement system designed in this paper can effectively suppress the influence of temperature and has good performance.The overall performance is far superior to the original piezoresistive pressure sensor.