Hi all,
I am working on a project that requires temp sensing from room temp (~70F) to 212F, with my range of interest from 195F to 208F with a resolution of 0.1F or better.
While there are dedicated ICs such as the AD7711 that do the job, they tend to be expensive, and I am hoping to learn something while I work on this project.
The research I have done seems to suggest :
1. Place the thermistor in a voltage divider, where the reference resistor is the same value as the thermistor in the middle of my range of interest, in order to maximise sensitivity.
2. The output of the voltage divider is then passed through a Instrumentation Amp with the gain set to fill as much of the ADCs input window as possible.
3. In code use the Steinhart-Hart equation to convert the ADC output to a temperature.
Does this sound right? Or have I missed something?
I am working on a project that requires temp sensing from room temp (~70F) to 212F, with my range of interest from 195F to 208F with a resolution of 0.1F or better.
While there are dedicated ICs such as the AD7711 that do the job, they tend to be expensive, and I am hoping to learn something while I work on this project.
The research I have done seems to suggest :
1. Place the thermistor in a voltage divider, where the reference resistor is the same value as the thermistor in the middle of my range of interest, in order to maximise sensitivity.
2. The output of the voltage divider is then passed through a Instrumentation Amp with the gain set to fill as much of the ADCs input window as possible.
3. In code use the Steinhart-Hart equation to convert the ADC output to a temperature.
Does this sound right? Or have I missed something?