Termisztorok

Termisztorok, a portmanteau of "thermal resistor," are passive electronic components whose electrical resistance is highly dependent on temperature. Unlike ordinary resistors which exhibit a relatively small change in resistance with temperature, thermistors are designed to have a significant and predictable change. This makes them very useful for temperature sensing and measurement.

There are two main types of thermistors: NTC (Negative Temperature Coefficient) and PTC (Positive Temperature Coefficient). In NTC thermistors, the resistance decreases as the temperature increases. This is due to the presence of more charge carriers becoming available for conduction at higher temperatures. Conversely, in PTC thermistors, the resistance increases as the temperature increases. This behavior is often achieved using ceramic materials and can be more abrupt around a specific temperature point.

Thermistors are widely used in various applications. They serve as temperature sensors in automotive systems to monitor engine coolant and oil temperatures, in medical devices for precise temperature monitoring, and in household appliances like ovens and refrigerators. They can also be used as inrush current limiters in power supplies, where their resistance is high at room temperature, limiting current during startup, and then decreases as they heat up, allowing normal operation. Their sensitivity, relatively low cost, and ease of use make them a popular choice for many temperature-related applications.