Custom homebrew temp sensor
Posted: 18 Oct 2011, 19:28
As I understand it, the lego temp sensor will measure from -20°C to 120°C, using 1023 raw values -giving a resolution of approx 0.14°C.
My problem is, I wish to measure temperatures between 70°C and 100°C a bit more accurately - about 0.02°C should theoretically be possible?
How would I go about constructing such a sensor?
Is is just a case of selecting a thermistor and resistor(s) to alter the signal sent to the NXT (a la homebrew temp sensor - 10K thermistor and 2k2 resistor in series)? If so, could anyone provide a schematic for me to work off.
Then I will have the problem of calibrating the custom sensor, so the data read by the NXT can be translated into a temperature using the temp curve of the thermistor - how will this be affected by any other components in the device?
Any help on this problem would be greatly appreciated.
My problem is, I wish to measure temperatures between 70°C and 100°C a bit more accurately - about 0.02°C should theoretically be possible?
How would I go about constructing such a sensor?
Is is just a case of selecting a thermistor and resistor(s) to alter the signal sent to the NXT (a la homebrew temp sensor - 10K thermistor and 2k2 resistor in series)? If so, could anyone provide a schematic for me to work off.
Then I will have the problem of calibrating the custom sensor, so the data read by the NXT can be translated into a temperature using the temp curve of the thermistor - how will this be affected by any other components in the device?
Any help on this problem would be greatly appreciated.