Reading temperature

 Temperature measurement using PmodTMP2

    One of the tings I wanted to do is to measure and read temperature with precission. I know there are lots of sensors and quite cheap, for example LM35, but I wanted a sensor which does all conversion and you just read the value, without the analogue problem as it can introduce error.

    I have chosen this because it is small, measures positive and negative temperatures, interfers it with I2C protocol, its precission is better than 0.25ºC and its resolution is 0.0625ºC. Consult the inner chip ADT7420. 

    Obviously the chip is difficult to solder but they sell it with a small board and you only have to connect it through its pins. I bough it in Digikey, address https://www.digikey.es/products/es?keywords=pmodTMP2

    The following diagram shows how to connect this board to the Atxmega128A3U. 

   

    The value of the resistors R1 and R2 are not critical and they define the signals according to the speed. You should see those signals as a nice square ones, if not, too bend, change its values.

    Finally you program the microcontroller using the board Atxmega and the programmer JtagIce to see the values online, connected to the chip.

 Program: Temperature.c