基于非线性温度传感器的高精度测量方案设计

Design of High Precision Measurement Scheme Based on Nonlinear Temperature Sensor

针对NTC热敏电阻应用于高精度温度测量时,存在其R-T(电阻-温度)特性呈非线性关系以及温漂影响测量精度等问题,设计了一种高精度测量方案。该方案选用四线制与传感器连接,采用微小恒流源作为激励,自适应选择通道进行数据采集,并通过USB通信把数据传送到PC机进行数据拟合。经验证,设计的传感器功耗低至0.1μW,温度测量精度大于0.01℃,特别是在20~50℃区间,测量精度大于0.000 5℃,能够满足高精度测量的要求。此外,经测试,该设计方案还可以应用于压力、加速度等非线性传感器的高精度测量,适用范围广,测量精度高、稳定性好、操作简单。

For defects of R-T （resistance-temperature） characteristic is non-linear and temperature drift when NTC （negative temperature coefficient） thermistor was applied in high precision temperature measurement, a kind of high precision measuring device was designed. The scheme connected four wire system and sensor, tiny constant current source was used as the excitation, and the adaptive selection channel was used for data acquisition, and data was transfered to the PC for data fitting through the USB communication . After verification, the design of the sensor power consumption is as low as 0.1 μW, the temperature measurement accuracy is greater than 0.01 ℃, especially in the range of 20 ℃ to 50 ℃, the measurement accuracy is greater than 0.000 5 ℃, which can meet the requirements of high precision measurement. In addition, after testing, the design scheme can also be applied to the high precision measurement of the nonlinear pressure and acceleration sensor, and has wide application range, high measuring precision, good stability, simple operation, and has certain practical value.