Interfacing NTC thermistor with 8 bit ADC

[Maverickmax]

Hi

Is there any example of interfacing with NTC themristor with 8 bit ADC before microcontroller chip?

What about the forumla converting the votlage reading into temperature?

My sensor measure 10k ohm at 25 degree....and the maximum range is 270 degree at about 800 ohm...

So I aint exactly sure how to measure the temperature from NTC thermistor.

Any help that meet my requirement will be rewarded with 50 points

Maverick Max

 

[thuvu]

Re: NTC themristor + ADC

It depends on the application. That's because NTC are not linear devices. But if you use them for a short range of temperature you can say that they are.

Check out the following pdf.

 

[thuvu]

Re: NTC themristor + ADC

and this

 

[thuvu]

NTC themristor + ADC

If you want to use it for a large range of temperatures and the accuracy of the ADC it's not enough for that you can "divide" this range to smaller ones. Then with a small DAC (ex 4bit) and an input amplifier(op amp) you can set different gains for each area in order to achive better accuracy.