Development Of Gas-Sensing Materials Test System Based On ARM

Gas sensors are widely used in toxic gas detection, industrial control and other fields.With the increasing gas detection requirements in industrial control, the measurementtechnology of gas sensing has become the new direction. Computer technology, especially thedevelopment of microcomputer technology, has become an increasingly control of such astemperature, flow and pressure parameters for a number of industrial control systems. Thepaper has studied the sensing mechanism of gas sensors, and designed a new type ofgas-sensitive materials test system. The LPC2138of ARM7architecture is the core of system,and it has powerful data calculation processing and control capability. In addition, theLPC2138integrated many hardware circuit interfaces, so the system is cheaper and smallerthan others. There are two parts, the hardware and the software. The hardware parts include:high-current power, testing system based on ARM, signal acquisition circuit, etc. Thesoftware parts include: the A/D converter program, the LCD program, PC program, etc. Thebasic principle is that the resistance of the sensors changes with the outside temperature. Thissystem has the advantages of high sensitivity, small and low-power. PC has the powerfulmonitoring and managing capabilities, while the microcontroller is fast and flexible controlfeatures. How to implement the communication between PC and MCU is a very importantpractical significance. The microcontroller completes control and data acquisition in the fieldof automation. The host computer will complete data acquisition, display, analysis, processing,printing and so on. Communications by serial interface RS-232to USB through FT232are beused. Development of new gas sensing materials or changing the structure can improve theperformance of the semiconductor materials. At present, the new gas-sensing materialscontain nano-materials, mesoporous materials, composite materials, and organicsemiconductor materials, etc. Because of the large surface area and surface activity, it hasbeen widely used in the development of gas sensors. This paper has designed a new,high-precision smart gas sensing measurement system. This paper has done test and analysisof gas-sensitive samples prepared by the system.