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I need help choosing a thermistor. I’m not sure what I need to look for. Let’s say I have this circuit measuring temperature:

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I have a range of temperatures from 0 to 10 degrees that I need to measure. I need outputs between 0 to 5 volts based on those temperatures.

I can’t seem to find how to choose a thermistor. I have found how to calculate the resistance of the fixed resistor to maximise sensitivity and range. I would choose a resistance that is the same as the thermistor when the thermistor is at a nominal temperature...

Thanks.

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The most suitable thermistors for temperature measurement are NTC types. The sensitivity is similar for most types (Beta in the range of 4000, give or take). If your range is 5°C +/- 5°C you might have an output of 2.5V +/-0.3V. If you want more like 0-5V you'll have to offset and amplify it.

Physical characteristics have to match the requirements- leaded, SMT, waterproof etc.

Other than that, the main thing is to pick an accuracy that is good enough and a resistance that is high enough that self-heating does not cause too much error, and not so high that whatever is reading it has problems (for example, an ADC might specify no more than 2.5K source impedance*. If the latter is a problem then a buffer amplifier can be added.

* the maximum source impedance is 1/(1/R + 1/Rtm) where Rtm is the resistance at the minimum temperature (maximum resistance).

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