Here is a cool project that we found on Hackalog.
As you all know there are many useful applications of temperature and relative humidity measurements sensors. They are readily that are available on the market consisting of both temperature and humidity sensors, signal conditioning, Analog to Digital Conversions (ADC), calibration and communication interface built in single module packages.

how to do a temperature sensor using a low cost diode?
The diode is a temperature sensor by itself due to the fact that it’s transfer characteristic is dependent of the temperature.
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