Thermistors

Effect of Temperature on Resistance:
Temperature affects the value of the resistance. Pure metals such as copper and aluminum resistant high temperature because the temperature increase caused power electronics and so increase the free speed, therefore, increasingly colliding with the metal ions are becoming more and more resistance to the passage of these electronics.
Altobeiran can change the resistance temperature change by a factor called the coefficient of thermal resistance that has the symbol α.
Is the amount of change in the value of the conductor resistance of 1 ohm when I change the temperature one degree Celsius

There are two types of thermistors:
1 / resistance of the positive thermal coefficient (PTC)A resistance increase in value of increasing the temperature, certain types of semiconductors when the temperature rises in 1950 to 150 m e. e., it increases its resistance suddenly.
Has been to take advantage of this property in the manufacture of thermal resistors with the positive coefficient of thermal resistance (PTC).

2 / resistance with a negative thermal coefficient (NTC):A resistance is worth less with increasing temperature and are made of carbon, semiconductors and called these materials Balmouselat hot any materials that increase the conductivity hight temperature shows the curve change resistance of these materials with temperature, and take the temperature, which is running the equipment to resist thermal coefficient Negative thermal resistance term starts from the 1950 percentage, up to 400 m and e. about using these types of resistors in the electrical measuring devices and transducers used to measure small temperature

 

 

Thermistor Characteristics