Temperature sensor communicates over a 1-Wire bus
The MAX31825 temperature sensor from Maxim Integrated communicates over a 1-Wire bus that, by definition, requires only one data line (and ground) for communication with a microcontroller.
In addition, the sensor can derive power directly from the data line ("parasite power"), eliminating the need for an external power supply.
The MAX31825 temperature sensor, which is available at distributor Digi-Key provides 8-bit to 12-bit Celsius temperature measurements with better than ±1°C accuracy from 0°C to +70°C and ±1.75°C from -45°C to +145°C.
Each sensor has a unique 64-bit serial code, which allows multiple MAX31825 ICs to reside on the same 1-Wire bus.
In addition, it includes two address input pins that, using an external resistor and pin-strapping, allow one of 64 different addresses to be selected to identify each sensor's physical location.
Therefore, it is simple to use one microprocessor to control many devices distributed over a large area.
The MAX31825 is available in a 6-bump WLP package. The power supply voltage range is from 1.6 V to 3.6 V for external power supplies, and from 2.3 V to 3.6 V for parasite power. The operating temperature range is from -45°C to +145°C