The DS18B20 Temperature Sensor is a digital temperature sensor that provides 9- to 12-bit digital temperature measurements and has an alarm function with non-volatile, user-programmable upper and lower trigger points.
Communication between sensor and microcontroller:
The DS18B20 sensor communicates via a bus that requires only one data, power, and ground pin to communicate with a microcontroller. Since each sensor has a unique 64-bit address, multiple temperature sensors can easily be used on one bus. The sensor does not require standBy power, which means that when no temperature data is being read, no power is consumed.