Digital thermometer with better than 0.5C resolution?
CuriousOne
Posts: 931
Hello.
I'm looking for digital, factory calibrated thermometer, which will have better than 0.5C accuracy in range of 15-95C. Does such ones exist? so far, I've found only MAX31723 to be close to required specs.
All interfaces will be OK, but SPI is preferred.
I'm looking for digital, factory calibrated thermometer, which will have better than 0.5C accuracy in range of 15-95C. Does such ones exist? so far, I've found only MAX31723 to be close to required specs.
All interfaces will be OK, but SPI is preferred.
Comments
PS, right now Parallax's is the deal of the day too!
Your thread title mentions "precision." The body talks about "accuracy." Those are two very different things. Which do you mean?
-Phil
Regarding the accuracy vs precision, according to picture in wiki, I need them both
It shows a typical (average?) accuracy of +/- 0.1 °C over a wide temperature range, bracketed by a bowtie curve at 3 standard deviations on each side. That would make it seem that if you were to draw a random specimen of the part from a parts bin, you would stand a pretty good chance of hitting your required accuracy. At least, at around room temperature. The spread is much higher at your high temperatures.
Another one to consider is the LM92, i2c interface, claiming +/- 0.33 °C limit of error at 30 °C. If you dig into the data sheet though, it is not so good as it moves away from room temperature.
Andrew mentioned the Sensirion products. You didn't mention needing RH, but Sensirion also offers the temperature-only STS21 (i2c interface) which claims a typical 0.2 °C "typical" tolerance over a fairly wide range.
What is the application or location? Sometimes you can improve the results with your own calibration, in which case you can get along with a generic (cheaper) sensor.
Sure, there are a lot of DIY ideas available online, but most of them are either way too simple and less precise, or precise, but way too expensive ($599 for thermal cycler DIY kit, and case is made from plywood ) So we want to build something that will have good accuracy and precision, but won't have aircraft prices.
I want to build it around BS2 oem and parallax usb datalogger.
The friend's son is not named Frankenstein is he? :-)