There are a lot commercially available digital thermometers in the market but why buy when you can build one?
This project is very straight forward; it uses a PIC16F84A microprocessor and Dallas Maxim’s DS18B20 programmable resolution 1 wire digital thermometer to measure the temperature. The PIC16F84A is used to set the digital thermometer’s resolution and to read the temperature data using 1-Wire interface. Two 7-segment displays were used as the temperature indicator. The DS18B20 is capable of measuring temperatures from -55 to 125 degrees Celsius however the rest of the other components are not rated to operate at the temperature extremes. The device can still be used to measure the extremes of the range given that only the DS18B20 is exposed to the very hot/cold temperature.