PSOC在高精度温度测量中的应用

Application of PSOC in high-precision temperature measurement

铂电阻是高精度温度测量的主要传感器之一,由于铂电阻的非线性使测量的精度受到影响。文中介绍利用一体化数字与模拟混合处理器PSOC实现高精度温度测量的方法,PSOC中包含温度测量所用到的主要元器件。设计采用流过恒流源的校准电阻与铂电阻比较的方法消除恒流源与模数转换器引起的测量误差,精确地测量出铂电阻的电阻值,再通过采用曲线拟合求得的高阶多项式计算出温度值。经理论推导和实际验证,利用PSOC进行RTD测量精度高,测量通道多,便于模块化和网络化,是一种值得深入研究和推广应用的高精度温度测量方法。

The platinum resistance is one of the primary sensors for high-precision temperature measurement on account of its nonlinear features resulting in the varying precision of the measurement. A high-precision measuring approach with the use of integrated digital and analog hybrid processor PSOC which includes the main components for temperature measurement. This design applies the method of contrasting the calibration resistance which flows through the current source and the platinum resistance to eliminate measuring errors caused by the current source and the ADCs. It can measure the value of the platinum resistance precisely and calculate the value of the temperature through the polynomial obtained by curve fitting. Deduced by the theory and proved by applications, this method using PSOC to implement RTD （resistance temperature detector） measurement has the merits of high precision, more measuring- channels, easier to realize modularization and networking. For these reasons above, it is a high-precision measuring approach which is worth doing further research and widespread use.