NTC thermistors

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The thermistor is an element that detects temperature. It is made of a semiconductor material that captures all temperature changes. They have negative temperature coefficients. In this case, the resistance of the thermistor decreases when the temperature increases, this one is then also called NTC thermistor.

When the Joule effect (heating due to the passage of current) is negligible, we can express a relation between the resistance of the NTC and its temperature by the following relation:

The temperatures are  in degrees Kelvin, B and T0 are constants of the component..

NTCs are made from oxides of transition metals (manganese, cobalt, copper and nickel). These oxides are semiconductors.


Characteristics:

NTCs can be used in a wide temperature range, from -200 ° C to + 1000 ° C, and they are available in different versions: glass beads, discs, bars, pellets, washers, chips etc.

 The nominal resistances range from a few ohms to a hundred kohms. The response time depends on the volume of material used.

NTCs are used for temperature measurement and control, transient pulse suppression, liquid flow measurement.



 
Resistance versus temperature plot for a thermistor.


Advantages :

The reasons for the popularity of thermistors for measuring temperature are as follows:

  • Greater change in resistance per degree of temperature providing better resolution.
  • High level of reproducibility and stability.
  • Excellent interchangeability.
  • Small size means quick response to temperature changes.


The applications of NTCs :

 They are used in a wide variety of applications including: 

  • fuse replacement.
  • automotive cabin heaters.
  • temperature controlled oscillators.
  • 3D printhead heaters .
  • lithium-ion battery protection circuits.
  •  peak current limitations for a power supply
  • voltage stabilization.
  • thermometric probe.






sources:
https://www.omega.fr/prodinfo/thermistances.html
http://www.composelec.com/thermistance.php
https://www.conrad.fr/o/resistances-ntc-thermistance-0241510?price_max=2.74&price_min=0.18


Comments

  1. SaritaJune 11, 2021 at 4:06 AM

    The NTC Thermistors market is expected to grow at a faster pace since they are an integral part of many types of equipment where temperature plays a role. Since temperature monitoring and control are used across a wide gamut of industries and there is an increase in investment across these sectors, the thermistor market is set to grow at an alarming rate. See More @ https://www.valuemarketresearch.com/report/ntc-thermistors-market

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