Eblock Thermometers FEZ Panda II

NETMF & Gadgeteer
1

Hi,

I´m new at this, and I need your help.
I´m using Fez Panda II board with thermometers and I have some doubts:

  • I have read that the temperature scale in Celsius for that sensor is [-22;56], but in other site is [-20,54], ¿which one I choose?
  • Other doubt is that I´m using it to measure the corporal temperature, but this value is not correct, it´s lower than the correct one. For example, with a typical digital termometer I have 36, and with the sensor I have 30. ¿Which is the problem?

Thank you very much, and I´m sorry about my English :slight_smile:

2

Did you put :

thermometer.SetLinearScale(-22, 56);

in your code ?
or

thermometer.SetLinearScale(-20, 54);

I just can’t find my eBlock to check by myself :frowning:

3

Those sensors are analog temperature sensors. You need to play a bit with the range until you are satisfied.

4

I don’ t use SetLinearScale because it returns a integer value, and I want a double value.
Like the sensor is analog (10 bits) I know that the function read() return a value between [0,1023] and this value is multiplied by ((56+22)/1024) - 22 . So I get a double value.
But the problem is the precission of measure, ¿can be used the thermometer to measure corporal temperature?

thank you again.

5

If you want precise calibrated temperature measurements, you’re better of with a digital temperature sensor like Maxim’s DS18B20 (up to 12 bit precision)

6

I think a don’ t need more precision, because I only need one decimal.¿ I really need it?
Could I calibrate it only adding a value ?

7

There’s a big difference between precision and accuracy. 12 bits is lots of precision, but says nothing about the accuracy. Are you looking for high accuracy or high precision?