Design Of Multi-channel Thermal Resistance Temperature Measurement System Based On FPGA

The rapid development of electronic technology provides more advanced alternatives of device selection which are used to develop temperature measurement technology towards high precision and integration.Temperature measurement circuits are widely used in industry,agricultural production,aerospace,scientific research and other fields,it is also an important part in the development and production of space environment simulator.Space environment simulator which is mainly composed of test vessels,heat sinks,vacuum exhaust units,high and low temperature processes,test device platforms,and temperature sensors,devices,control units etc.is a multi-functional and comprehensive test equipment designed for simulating various environmental factors on the ground.This paper investigates the current situation of domestic and foreign research on space environment simulator,and finds some problems,like low accuracy due to temperature measurement,weak signal anti-interference ability,and the temperature measurement lead Vacuum tightness and other issues,then design a multi-channel thermal resistance temperature measurement system for space environment simulator to complete multipoint the temperature by using field programmable gate array(FPGA)devices,special thermal resistance A / D conversion chips,and intelligent information processing technology.The multi-channel thermal resistance temperature measurement system designed in this paper is suitable for high and low temperature measurement under normal temperature and vacuum environment to achieve multi-channel temperature data collection,and the writer uses parallel processing mode,including analog to digital conversion,filter processing,resistance value conversion,search index etc.to reduce system noise interference and improve data accuracy.The whole system adopts SPI communication bus technology,which is used to realize the communication between FPGA and A / D conversion chip and MPU,and realize the data interaction.This design mainly includes hardware circuit design and software design.Altium Designer17 software is used to complete the A / D data acquisition and conversion circuit,FPGA control circuit,SPI communication circuit schematic diagram and PCB design.The entire system circuit board is drawn by soldering components.Utilize the hardware description language Verilog HDL to complete the internal circuit design of the chip to realize the needs of each functional module;through software and hardware testing and analysis of the test data,verify the rationality and functionality of the system design and realize the collection of multi-channel thermal resistance temperature data.