Thermistors are temperature-sensing elements made of semiconductor material that has been sintered in order to display large changes in resistance in proportion to small changes in temperature. This resistance can be measured by using a small and measured direct current, or dc, passed through the thermistor in order to measure the voltage drop produced. These solid state temperature sensors actually act like electrical resistors that are temperature sensitive. That is where the name, a clear combination of the words thermal and resistor, comes from. Ametherm specializes in NTC, or negative temperature coefficient, thermistors.
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