远距离温度信息传输稳定性研究

Research on the Stability of Remote Temperature Information Transmission

数字式温度传感器DS18B20在工农业已得到广泛的应用。针对DS18B20进行远距离温度采集时会出现温度信息不稳定的现象,对DS18B20通信协议以及温度信息传输的原理进行了研究,发现导线的分布电容和电磁干扰是影响温度信号远距离传输不稳定的主要因素。提出了改变导线的上拉阻值和采用屏蔽技术的解决方案。实测结果表明,该解决方案可显著提高远距离温度采集传输的稳定性,进而保证温度采集系统的可靠性。

Although digital temperature sensor DS18B20 has been widely used in industry and agriculture, the unable phenomenon of temperature information occurs when collecting temperature remotely. The communication protocol of DS18B20 and the principle of temperature information transmission are researched. It is found that the distributed capacitance of the wire and electromagnetic interference are the main factors cause the instability. The solution of changing the pull-up resistance of the wire and using shield technology is proposed. The result of practical test indicates that this solution significantly increases the stability of the remote temperature acquisition and transmission, thus ensures the reliability of the temperature acquisition system.