基于单片机的程控电压输出装置  

Programmable voltage output device based on microcomputer

作　　者：王嘉军 马善达 梁威 叶奔 季康 WANG Jiajun;MA Shanda;LIANG Wei;YE Ben;JI Kang(Jiangsu Rayer Medical Technology Co.,Ltd.,Wuxi 214000,China)

机构地区：[1]江苏瑞尔医疗科技有限公司,江苏无锡214000

出　　处：《电子设计工程》2021年第5期90-94,共5页Electronic Design Engineering

基　　金：2019年江苏省重点研发计划专项资金(社会发展)(BE2019781)。

摘　　要：在工业控制中,常常需要可定时的0~10 V电压信号来控制设备。因此,需要设计一种可程控、安全性高、准确性高的电压输出装置。文中以STC12C5A60S2单片机为主控芯片,通过485接口实现主控芯片与上位机的命令交互。利用单片机的定时器实现定时功能,结合DAC8562数模转换芯片,输出两路0~2.5 V的电压,并通过OPA277放大芯片实现4倍放大,从而实现0~10 V的电压。为了实现安全性,通过BL1551模拟开关,选择DAC8562中最接近理论电压的通道输出到OPA277实现放大,最后通过继电器模块输出电压。通过比较10组理论电压与实际电压,得出0~10 V的电压输出平均误差为0.016 V,通过比较10组理论定时时间和实际定时时间,得出定时的平均误差为7.4 ms,满足工业设备远程控制的要求。In industrial control,a timed 0~10 V voltage signal is often needed to control the equipment.Therefore,it is necessary to design a programmable voltage output device with high safety and accuracy.This paper takes STC12C5A60S2 micro⁃controller as the master control chip and realizes the command interaction between the master control chip and the host computer through the 485 interface.The timing function is realized by using the timer of the single⁃chip microcomputer,and the voltage output of 0~2.5 V is realized by combining the DAC8562 digital⁃to⁃analog conversion chip,and the voltage of 0~10 V is realized by four times of the OPA277 amplifier chip.In order to achieve safety,the analog switch BL1551 was used to select the channel in DAC8562 closest to the theoretical voltage and output it to OPA277 for amplification.Finally,the voltage was output through the relay model.By comparing 10 sets of theoretical voltage and actual voltage,the average error of voltage output of 0~10 V is 0.016 V.By comparing 10 sets of theoretical fixed time and actual fixed time,the average error of fixed time is 7.4 ms which can meet the remote control requirements of industrial equipment.

关 键 词：STC12C5A60S2 DAC8562 OPA277 模拟开关 继电器模块 

分 类 号：TN07[电子电信—物理电子学]