I need an accurate thermometer for my research (-10~110 C), because the commercial ones are not programable . I would like to have a +-0.001 C accuracy one (maybe it is not possible at all ). But after checking around, all I have found are at best +-0.1 one (tmp117). I found some with 24bit ADC in it but only claim +-0.1 C accuracy ( TSYS01), which confuses me quite a lot, why a 24bit ADC can only achive a +-0.1 C accuracy?
Then I think it might be a good idea to build one. I have chosen a good NTC thermoresistor and a good 24bit ADC. What else do I need ? Maybe need a good bridge circuit to read the value of the NTC resistor and a stable voltage reference? Any better idea?
Note the reading doesn't have to be very fast. 0.24 Hz final reporting rate is fine.
So far the best commercial one I have found is this:
I think 0.001 c accuracy might not be possible...