基于STM32F103的智能温度变送器设计  

作　　者：陈剑 吴桂峰 

机构地区：[1]扬州大学电气与能源动力工程学院,江苏扬州225000

出　　处：《科技创新与应用》2022年第1期92-94,98,共4页Technology Innovation and Application

摘　　要：传统温度仪表存在测量精度低、数据传输距离较近以及非智能等缺点,文章针对这些缺点设计了一种一体化智能温度变送器。该温度变送器以STM32F103微处理器为核心,外接24位高精度模数转换芯片AD7794,采用16位DA芯片AD5421实现4~20mA环路电流输出,通过对采样电路的设计可实现多种热电偶(带冷结补偿)及热电阻(三线式或四线式连接)信号的采集和处理;同时外加调制解调芯片AD5700实现HART通信。整个电路设计简洁、精度较高、稳定性好,具有一定的实用价值和应用前景。The traditional temperature instrument has the disadvantages of low measurement accuracy,short data transmission distance and non intelligence.Aiming at these disadvantages,this paper designs an integrated intelligent temperature transmitter.The temperature transmitter takes STM32F103 microprocessor as the core,external 24 bit high-precision analog-to-digital conversion chip AD7794,and uses 16 bit DA chip AD5421 to realize 4~20mA loop current output.Through the design of the sampling circuit,the signal acquisition and processing of various thermocouples(with cold junction compensation)and thermal resistors(three-wire or four-wire connection)can be realized.At the same time,the modulation and demodulation chip AD5700 is added to realize HART communication.The whole circuit has simple design,high precision and good stability,so it has certain practical value and application prospect.

关 键 词：温度变送器 高精度 环路输出 HART协议 

分 类 号：TP212.11[自动化与计算机技术—检测技术与自动化装置]