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The NTC thermistor is a versatile component that can be used in a wide variety of applications where the measurand is temperature dependent.

The current-time and voltage-current characteristics are associated with self-heated thermistors. The resistance-temperature characteristic is applicable to thermistors operated with negligible self-heat.

Applications which depend on the resistance-temperature characteristic include temperature measurement, control, and compensation. Also are included those applications for which the temperature of the thermistor is related to some other physical phenomena.

Applications based on the voltage-current characteristic of a thermistor generally involve changes in the environmental conditions or circuit variations which, in turn, result in changes in the operating point on any given curve or family of curves.

The current-time characteristic of a thermistor depends on its heat capacity and dissipation constant as well as the circuit in which it is used. Applications which make use of the current-time characteristic include time delay and surge suppression.

Self heating is mentioned as a problem with thermistors, but it is also the basis of fluid flow measurements using thermistors. If the thermistor is biased so that there is some self heating and a fluid is moving past it, the fluid will carry away heat in proportion to the speed of the fluid.

PTC thermistors can be used as current-limiting devices for circuit protection, as replacements for fuses. Current through the device causes a small amount of resistive heating. If the current is large enough to generate more heat than the device can lose to its surroundings, the device heats up, causing its resistance to increase, and therefore causing even more heating. This creates a self-reinforcing effect that drives the resistance upwards, reducing the current and voltage available to the device.