The Research Of Sensor Signal Conditioning Method And Test Equipment Solution

The main function of the sensor is to obtain information from the outside world.However,due to the semiconductor properties of the resistive sensor itself,there are some problems such as temperature drift,uniformity and non-linearity,which need to be compensated and calibrated in use.Although the traditional software and hardware calibration methods can compensate the signal to some extent,they still have many shortcomings.On the basis of the existing signal conditioning chip,the application solution of the autonomous signal conditioning chip is proposed,and several practical applications of the solution are described through typical applications.The application scheme of the autonomous signal conditioning chip and the traditional signal conditioning method have the characteristics of small size,low power consumption and high precision.The internal structure and corresponding functions of the autonomous signal conditioning chip are described in detail.The analog part of the chip mainly amplifies the signal,compensates the offset temperature coefficient and compensates the full-range temperature coefficient.The value of compensation will be converted into analog signal through DAC,and the input signal will be compensated before amplification.The digital part mainly has the register and the FLASH and so on memory,its main function is carries on the command operation and the communication.The digital part and the analog part describe how to calibrate the sensor signal from inside the chip.At the same time,in the actual use of the chip,design HKA2910 single-channel temperature compensation calibration software,can use at the bar menu prompt steps to modify the parameters of the register,by changing the parameters to generate fitting,first of all,through the input parameter calibration process,estimate the calibration process after successfully passed,for the main calibration operation,two calibration are passed,the output file final output compensation curve,finally write files to burn to the sensor control chip to complete the process.When a chip communicates with a computer,it needs to use a special interface board.By designing a single channel communication board,data communication and calibration compensation for a single resistance sensor are realized.However,in practical engineering applications,it is often necessary to unify a large number of automatic calibration scheme.By summarizing the experience of the single-channel communication board card,a multi-channel calibration board card is designed,which can realize the calibration of the 8-channel single-channel sensor,and is compatible with the current source and voltage source dual signal source input acquisition,and can realize a variety of connection modes of three-wire system,four-wire system and five-wire system with the sensor conditioning chip.At the same time,the industrial PC box with expandable boards is designed to expand the number of ways of calibration.Through the industrial PC box,the temperature box and pressure box can also be controlled,truly realizing the full automation of the calibration process,thus realizing the large-scale automatic calibration of resistance sensor.