What is thermistor?

Well, Today's article all about the thermistor, obviously, it's not a new word but often all are called as the temperature sensor. 

  Now a days, using this sensor getting very common, that means that much of familiar and powerful one. The thermistor is a word collection of Thermal and resistor. 

 What is thermistor:

  A thermistor is a non-linear resistor and it's a variable resistor too. It is an element with an electrical resistance that changes significantly in the response to temperature. 

According to the working of a thermistor bifurcated into two types, those are quietly opposite fundamental types

1. NTC type
2. PTC type

1. NTC TYPE:

    NTC shorted from Negative Temperature coefficient. In this when the temperature is increased then resistances of a thermistor is decreased. This is formally known as a temperature sensor. 

  The NTC type is used when a change in resistance over a wide temperature range is required. They are often used as temperature sensors in the range of -55°C to 200°C, although they can be produced to measure much lower or higher temperatures.

 The following image for NTC thermistor.


thermistor symbol


ntc thermistor graph

 The above image is showing temperature vs resistance of the thermistor. When the temperature rises the resistance is decreasing. 


2. PTC type:

   PTC is shorted from positive temperature coefficient. When the temperature rises resistance of a thermistor is also increases. These are mainly used for protecting the overcurrent conditions.

The PTC type used when a sudden change in resistance at a certain temperature is required. They exhibit a sudden increase in resistance above a defined temperature, called the switch, transition of “Curie” temperature. The most common switching temperatures are in the range of 60°C to 120°C. They are often used for self-regulating heating elements and self-resetting over-current protection

The PTC type thermistor image as shown in below, 

PTC thermistor symbol
Thermistors are inexpensive, easily-obtainable temperature sensors constructed using semiconductor metal oxides, and are available with either  NTC of resistance or PTC of resistance.





    

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