摘要
在现代化的工业现场,常用热电偶测试高温,测试结果送至主控机。由于热电偶的热电势与温度呈非线性关系,所以必须对热电偶进行线性化处理以保持测试精度。该系统通过高精度模/数转换器AD7705对热电偶电动势进行采样、放大,并在单片机内采用一定算法实现对热电偶的线性化处理,再通过数/模转换器AD421进行数/模转换产生4mA～20mA电流,送主控中心。
Thermocouple is used frequently in high-temperature test in the modernized industry scene,then the test results are delivered to master control machine. As the non-linear relationship between thermoelectric potential and temperature, it must be carried out on the thermocouple linear processing in order to maintain accuracy of test. This article is for the linearization of thermocouple. The general idea is to study high-precision A/D converter AD7705, which samples and enlarges the thermoelectric potential from the thermocouple, to use a certain algorithm for the linearization processing in the microeontroller, and to convert the data to produce the 4 mA-20mA current through high precision A/D converter AD421.
出处
《微计算机信息》
2009年第23期88-89,共2页
Control & Automation
关键词
热电偶
线性化
AD转换
DA转换
单片机
Thermocouple
Linearization
AD conversion
DA conversion
Single-chip-micro-computer
