Low frequency noise measurement system for MnCoNi type NTC thermistor

摘要

Thermistor converts the change in incoming infrared light into the change in its resistivity,which can then be converted to the changes of an electric signal.Thermistors based on transition metal oxides of Mn3O4,Co3O4 and NiO(MCNO)are characterized by having high thermal constant and adjustable resistivity with concentration of metal oxides.Infrared detectors(IR)manufactured from this type of thermistors can be used at ambient temperature even in the presence of thermal noise,and are widely used in various industrial and advanced applications.Sometimes this kind of infrared detectors generate a false alarm.The random noise signal of the inner thermistor is the main source of the false alarm.This paper deals with the measurement of the low frequency voltage noise of the MCNO thermistor.A measurement set-up was built,and the fitted parameters of the digitized noise signal were given for further analyzing the characteristics of the thermistor.