In the data acquisition part, MCU is used to control MCU with A/D channel. The voltage or current that changes with the measured temperature is collected, and after A/D conversion, the data is processed by a single chip microcomputer, and the measured temperature is displayed by a display circuit. Thermocouple has the advantages of wide temperature range and small size, but it also has the disadvantages of low output voltage, easy to be affected by wire loop noise and large drift