Thermistor Basics: NTC vs PTC Thermistors Explained

This page covers thermistor basics, including a comparison of NTC and PTC thermistor types. We’ll also mention some prominent thermistor manufacturers. A thermistor is a semiconductor device whose resistance changes depending on temperature.

It’s also known as a thermal resistor. Thermistors come in various sizes and shapes, such as rods, discs, and beads.

There are two main types of thermistors: NTC (Negative Temperature Coefficient) and PTC (Positive Temperature Coefficient).

NTC Thermistors

In NTC thermistors, resistance decreases as temperature increases. These are typically made of oxides of nickel, manganese, copper, cobalt, and other materials.

They are mainly used for temperature control and measurement applications. NTC thermistors are heated either by the external surroundings or through the internal flow of current.

This resistance change results in a current or voltage change. This change is then fed as input to an electronic system, where it’s processed based on the application.

PTC Thermistors

In PTC thermistors, resistance increases as temperature increases. They are often made of barium titanate.

They are often used to protect electronic circuits from high temperatures. This effect can be observed in electric motors overloaded due to short circuits or other issues.

Thermistor Manufacturers

Here are some well-known thermistor manufacturers:

1. AMWEI
2. EPCOS
3. Murata Electronics - Thermistor Manufacturer
4. Selco Products Co.
5. Semitec
6. Spectrum Control
7. US Sensors Corp.
8. Semitec
9. Vishay - Thermistor Manufacturer
10. GE