Thermistors are cheap, stable, accurate and durable temperature sensors. Unfortunately they’re also nonlinear so they can be more difficult to use than other technologies. Here is an example of how to use a simple voltage divider and the Steinhart-Hart equation to adapt a standard analog voltage input for a thermistor.

If you’re in a rush, focus on equations (1) and (9).

Full Document: 2011-02-02 Thermistor Calibration

C. Cigas 2010