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The different between this two thermistor and where to find their datasheet? Answered

Hi Instructables members',
Can anyone tell me the different between this two thermistor and it application circuit:
1 - Thermistor_50s (see attached picture)
2 - Ptc_thermistor_500-800r_hmz13-05m650rn (see attached picture)

Thank you in advance



will give you some general background to help you understand the different types.

Exact differences may actually be simply their resistance.

Biggest issue - as Iceng says PTC positive temp coeffecient

NTC Negative ....

All the rest is about current and resistance.

Hi @rickharris,

Thank you for your valuable feedback. I am in-progress making this china inverter. Please refer to another question I just post. Here is the link >>


For the driver stage yup it is PTC and the power stage it was NTC. But which value shall I use?


I don't know. The symbol on the left is for a thermistor but the symbol on the right isn't it is as far as I can see just a resistor.

Without knowing the circuit requirements the resistance you need is difficult to establish. You need more information from the original designer.

:) Finally I found the info. The 50S (50 second) that require PTC to turn on circuitry in KA7500 driver module to drive an external cooling device to maintain the air temperature. And NTC/10K serves as an inrush current (instantaneous input current drawn by an electrical device when first turned on). Thanks for the link given, its help me to understand about the thermistor application.


3 years ago

Ptc => Positive-temperature-coefficient.

The days of data from China are no longer.

Hi @iceng,

Thank you for your valuable reply. Please refer to the reply I left for @rickharris.