RFID Fridge

A smart refrigerator for the home

Temp Sensor

One of the features supported by our fridge is a temperature sensor that reports the temperature inside of the fridge. We used a LM 34DZ analog temperature sensor capable of measuring from -50 to +300 degrees Fahrenheit. The sensor used an input of 5 V, and output a voltage equal to the current temperature * 10 (mV). To read the values coming from the sensor, we configured an ADC pin in our hardware project with 8 bits of precision. Because of the amount of precision we used and the way that the sensor reported values, we were able to use the raw data without any processing and/or manipulation to read the temperature. We then forwarded this value to be display on our screen.


While we were able to directly read all of the temperature values returned by the sensor, the data's accuracy was not necessary guaranteed. We solved this problem by reporting only a running average of temperature values to the screen to be displayed. This allowed us to mute the effect of the occasional inaccurate read.