1. What is a PTC Thermistor? 

Positive Temperature Coefficient Thermistor -

PTC Thermistors are an electronic component where the resistance remains almost constant near room temperatures. However, when the temperature exceeds a constant temperature, the resistance suddenly increases. 

2. Feautures

The distinctive characteristics of "PTC" can be acquired by adding a small amount rare earth elements into barium titanate (BaTiO3) .

Electrodes are formed in ceramics which use barium titanate as the main ingredient to create POSISTOR, and lead types and chip types are widely used.

 The three characteristics of PTC can be illustrated as in the following:

a). Resistance - Temperature Characteristic

b). Static Characteristic (Voltage-Current Characteristic)

c). Dynamic Characteristic (Current - Time Characteristic)

We would have a detailed introduction for PTC's three  characteristics in the next  chapter