I would like to implement a thermistor on my PCB, So when it gets too warm, and the its resistrance decreases, then somehow it will cause an interrupt to the MCU, so i'll know about this warming.
Do you have any idea which will be low cost and very few components to design it?
There are 2 types of thermistor, NTC and PTC. The one you're saying is the NTC (negative temperature coefficient). This is normally used in temperature sensing. It decreases the resistance as the temperature rises, thus, negative. The temperature response of this device is logarithmic and that is why it is more stable in temperature sensing. On the other hand, the PTC has the reverse effect as far as temperature is concern. It increases its resistance as the temperature rises. But the temperature response has a significant difference with the NTC. The resistance only rises suddenly at the temperature threshold. Meaning, if it is rate at 85ºC, the resistance is low before 85 and increase to its max resistance as it reaches 85. The application for PTC is usually for resetable fuse.
So, it depends on your requirement. Choose which one you want and I will help in the design (of course, thru this forum. So that others can have an idea also).
right, you can read voltage instead of resistor in a properly set circuit. don't forget to amplify the signal before putting it into ADC, so that u will have a better resolution.
right, you can read voltage instead of resistor in a properly set circuit. don't forget to amplify the signal before putting it into ADC, so that u will have a better resolution.
"The resistance only rises suddenly at the temperature threshold. Meaning, if it is rate at 85ºC, the resistance is low before 85 and increase to its max resistance as it reaches 85ºC"
A PTC thermistor simply increase in resistance as the temperature rises.
Only special thermistors have the characteristics you mention.
Ideally (maybe straight from college books), PTC should work this way. The resistance should rise as the temperature rise. But, as the manufacturers said, it's quite difficult to dope the PTC in order to have in this manner. Normally, PTC are switching type.
I have ask murata before if they have a PTC that is linear with respect to temperature. They explained to me more on the chemistry side in which I don't understand a thing. In short, it's difficult for them to produced such PTC. I don't know with other suppliers.
Some notes also from wikipedia where the writer says that most PTC's are switching.
What is a uC's? uC is a microcontroller
I'd rather have a circuit with low cost componetns, preferably resistors, diodes or transistors (something which is available).
The net should have several examples or reading a thermistor using an ADC (Analog to Digital Converter).
Most uCs have them built it.
And what sensor are you talking about? the thermistor
p.s. i'm not writing from the account there is in where i work, so sorry for the double name.
I would like to implement a thermistor on my PCB, So when it gets too warm, and the its resistrance decreases, then somehow it will cause an interrupt to the MCU, so i'll know about this warming.
Rather confusing , you used a few too many its.
Are you saying you want the thermistor isolated from the PCB and measuring a different temperature ? That does not change the circuit.