Internal Temperature Sensor Details

[Bryan]

I am looking for details on the internal temperature sensor on the nRF51822. I would like to use it to get a general ambient reading of the air around the device. Basically, I need to know if this temp sensor can be used for this function. If so, I need accuracy details. Thanks.

[Marc Nicholas]

Hi Bryan,

I think you may want to reconsider this.

The temperature sensor reads the die temperature of the nRF51822. The die temperature will not be the ambient temperature of the surroundings.

Now, you might be thinking "oh, I'll just offset it". That doesn't work either as the die temperature varies a fair bit based on what the chip is doing (and likely some other voodoo).

Finally, I believe some revisions of the chip have buggy silicon. I could be wrong on this point, but I'm almost certain one of the PANs mentions this.

Hope that helps.

-marc

[Ole Morten]

I have nothing further to add here, since Marc is spot on. :-)

The PANs could be worked around, but as Marc says, there are other problems causing this to not be a good idea if you want an accurate measurement.

[Bryan]

Thanks! That is the response I actually expected. I just needed confirmation to pass on to the hw guy.

[Ole Morten]

Great! If you found Marc's answer useful, I'd be happy if you could click the "Accept as answer" button below it, to show appreciation. :-)

[kk]

HI,Ole. If I only measure the temperature when in sleeping mode ,will the data be reliabled?