基于HCPL-7860的隔离型信号采集与传输模块的设计

Design of an Acquisition and Transmission Module for Isolated Signal Base on HCPL-7860

为了可靠便捷地采集常用的工业信号,提出了以AD芯片HCPL-7860和微处理器PIC16F74为核心的隔离型多通道信号采集与传输模块。对HCPL-7860的特性及应用、四线制铂电阻PT100的测温原理、恒流源电路和交流信号的采集方法进行了分析和研究,给出了模块的硬件电路设计和软件设计。现场应用结果表明,该采集模块精度高,性能好,能准确可靠地采集工业常用的铂电阻测温信号,0～5V电压信号,4～20mA直流电流信号和-5A～+5A交流电流信号。

In order to acquire the common industrial signals reliably and conveniently, this paper puts forward an isolated multi-channel signal acquisition and transmission module based on AD chip HCPL-7860 and microprocessor PIC 16F74. The Characteristics and Applications of HCPL-7860,the temperature measurement principle of the four-wire platinum resistance PT 100,the constant current source circuit and the acquisition method of the AC signal are analyzed and researched ,and the hardware circuit design and software design of the signal acquisition module are presented.The field application result showed that the acquisition and transmission module can acquire the common industrial temperature signal,0-5V voltage signal,4-20mA DC current signal and -5A-＋5A DC current signal accurately and reliably with high precision and good performance.