基于NTC的体温测量系统设计

Design of Temperature Measurement System Based on Negative Temperature Coeffcient

目的设计一款基于NTC热敏电阻的便携式体温测量设备。方法基于恒流源,以NTC热敏电阻为体温传感器,采用高精度差分式ADC芯片将模拟信号变为数字信号,送入单片机分析处理,同时给出各部分误差的来源以及误差校准方案,最后对设备进行实验验证。结果实验结果表明,经过误差校准后的体温测量设备测量误差小于±0.1℃,完全满足医用电子体温计的使用标准。结论此系统提出一种全新的设计方案,并且具有较强的稳定性和实用性;同时校准方案中所阐述的实时校准方法,对研究电子体温计的校准方法提供了一定的参考价值。

Objective To design of a portable temperature measurement equipment based on NTC thermistor.Methods Firstly,based on the constant current source,negative temperature coeffcient(NTC)thermistor was chosen as the body temperature sensor,and high-precision differential analog digital converter(ADC)chip was used to convert analog signal to digital signal.Then,the digital signal was sent into the microcontroller analysis and processing,the error source of various parts and calibration scheme were given.Finally,the equipment was experimentally verified.Results The experimental results showed that the measurement error of the body temperature measurement equipment after the error calibration was less than±0.1℃,which fully met the standard of medical electronic thermometer.Conclusion This system presents a new design scheme with strong stability and practicability.At the same time,the real-time calibration method mentioned in the calibration scheme also provides some reference value for further study of electronic thermometer calibration.