基于AT89C51单片机的高精度测温系统的研制

Design of a High Accuracy Measuring-temperature System Based on AT89C51

对特殊的环境温度进行测量,不仅要求测量的实时性,而且要求测量的精确度,使测量的温度达到既定的标准。因此作者介绍了一种应用铂电阻进行高精度的温度测量系统,系统中以Pt100铂电阻作为测温传感器,采用最小二乘法来消除测温系统的非线性,并应用24位Σ-Δ高性能模数转换器AD7714对所输入的模拟信号进行模/数转换。AD转换器AD7714的应用保证了0.001℃的测量分辨率,最小二乘法的非线性优化使系统的测量误差小于0.01%。

when measuring temperature in some special circumstances, the precision is an important guide line, so the measuring-temperature system must has a higher precision. A measuring-temperature system was introduced, in the system a kind of platinum resistor Pt100 is used as the temperature sensor and the least square method is applied to eliminate the non-linearity of Pt100 platinum resistor. In the system a 24 bit Σ-Δ analog to digital conversion AD7714 was applied, using AD7714 makes the resolving-rate of measuring system arrive at 0.001℃. The least square method optimization makes the measuring error less than 0.01%。