K型热电偶冷端补偿方案

Design of K-Thermocouple cold-junction compensation

回流焊是SMT行业中的关键工序,而印制板焊接的温度曲线却差异很大。国内SMT行业已经认识到这点,相继开发出各种温度曲线记录器,但受到SMT工艺中环境温度的制约,测量精度一直难以提高。本文在理论分析和实践的基础上提出一种简单可靠的热电偶冷端温度补偿方案,可以将测量精度由±2℃提高至±0.5℃。

The reflow soldering is the key working procedure for SMT,but the temperature curves of printed circuit board are widely divergent.The homeland SMT industry has been awared the importance of these curves and excogitated such kinds of thermograph.Base on theory analysis and practice summarize,this article gives a high reliable cold-junction compensation scheme,which can improve the system error from ±2℃ to ±0.5℃.