NTC Thermistors

NTC – negative temperature coefficient – thermistors are used as a type of resistor in electrical circuits. Negative temperature coefficient means that as the temperature of a circuit rises, the resistance level decreases. While this may appear as counterintuitive, NTC thermistors serve a specific purpose when circuits are first powered up, enabling them to work effectively. NTC thermistors are also sometimes called current protection devices or power thermistors.

What are NTC thermistors used for?

NTC thermistors are used as inrush current limiters, helping to protect electrical circuits from being destroyed by the vast electrical current that flows in the fractions of a second after a device is switched on.

How do NTC thermistors work?

NTC thermistors have high levels of resistance at room temperature. When electrical current is flowing, NTC thermistors heat up, which reduces their resistance and allows a safe level of current to flow.

What are the benefits of using NTC thermistors?

Unlike some other types of resistor, NTC thermistors limit the flow of current, but enable enough to current to flow so that there is no drop in power or in the performance of the device in question.

What’s the difference between NTC and PTC thermistors?

Whereas the resistance of NTC thermistors decreases as the temperature rises, with a PTC – positive temperature coefficient – thermistor, the opposite occurs, with resistance increasing alongside the temperature.