Experimental Research on the Stability of Negative Temperature Coefficient Thermistors

Four different types of negative temperature coefficient thermistors were tested at high temperatures for more than 1000 h to test their thermal stability. Moreover, these four types of negative temperature coefficient thermistors underwent up to 60 times for thermal shock testing. The thermistor temperature drift and change in B-value were observed throughout the testing. The findings reveal that adequate annealing can eliminate the stress of these newly designed thermistors. Additionally, long-term annealing produces sustained temperature drift in particular types of thermistors. The thermistors' temperature drift during the annealing process is typically less than 10 mK every 100 h. Thermal resistance drifts less than 5 mK after 60 instances of thermal shocks. The study makes manufacturing high-precision thermometers feasible, with test data ranging from 273.15 to 373.15 K.