A linearization scheme of thermistor temperature sensor
Hua Yang, Hao Liang, Yuanji Song, Fei Sun, Shengmei Liu, Xiangdong Wang · 2022
The method of using the detection of temperature gradient is a new method to achieve turbulence observation. Most of the currently used temperature sensors are negative temperature coefficient nonlinear thermistors, but the degree of linearization of thermistor temperature sensors is an important factor affecting the accuracy of turbulence observation. In this paper, a low-cost two-stage linearization scheme for thermistor temperature sensors is proposed to address this problem. The first stage is a hardware linearization circuit based on the OPA2277 integrated operational amplifier. The second-stage linearization adopts the fitting between the first-stage output voltage and the real temperature based on the fourth-order fitting temperature calibration method. This linearization scheme trades off fast response to temperature and measurement accuracy. The linearization scheme based on this thermistor temperature sensor is in the temperature range of 0~32°C, and the maximum absolute temperature error is only 0.056°C, which is much smaller than the linearization scheme in the existing literature.