Wholesale PTC Thermistors

PTC Thermistor: Positive Temperature Coefficient Thermistor

A PTC (Positive Temperature Coefficient) thermistor is a type of thermistor whose electrical resistance increases with an increase in temperature. This characteristic distinguishes it from NTC (Negative Temperature Coefficient) thermistors, where resistance decreases with temperature. Key Features of PTC Thermistors: Positive Temperature Coefficient: The most defining feature of PTC thermistors is their positive temperature coefficient. As the temperature rises, the resistance of a PTC thermistor increases, providing a predictable and measurable response to temperature changes. Applications:

• Overcurrent Protection: PTC thermistors are often employed as self-resetting fuses or overcurrent protection devices. When subjected to an overcurrent condition, the temperature of the PTC thermistor increases, causing a significant rise in resistance and limiting the current flow.
• Temperature Sensing: PTC thermistors are used in temperature-sensing applications where their resistance variation with temperature is utilized to measure or control temperature in electronic circuits.

Self-Heating Effect: PTC thermistors exhibit a self-heating effect. As current passes through them, their resistance increases, leading to an increase in heat generation. This self-heating effect can be harnessed in certain applications. Resettable Functionality: Due to their positive temperature coefficient, PTC thermistors can have resettable functionality. After an overcurrent event or a temperature excursion, they can return to a low-resistance state once the condition is removed. Varieties: PTC thermistors come in various shapes and configurations, including chip, disk, and bead forms. The specific design and application determine the appropriate type of PTC thermistor to be used. In summary, PTC thermistors are valuable components with a positive temperature coefficient, finding applications in overcurrent protection, temperature sensing, and other scenarios where their unique electrical characteristics can be utilized.