View ds18b20x datasheet:

DS18B20X Flipchip 1-Wire® Digital Thermometer www.dalsemi.com FEATURES PIN ASSIGNMENT • Unique 1-wire interface requires only one port pin for communication (TOP VIEW) • Each device has a unique 64-bit serial code stored in an on-board ROM GND VDD • Multi-drop capability simplifies distributed temperature sensing applications • Requires no external components 28rrd • Can be powered from data line. Power supply DQ GND range is 3.0V to 5.5V • Measures temperatures from –55°C to Branding legend: +125°C (–67°F to +257°F) 28 = family code rr = revision code (i.e., B6) • ±2.0°C accuracy from 0°C to +70°C d = one letter date code • Thermometer resolution is user-selectable from 9 to 12 bits See Mechanical Specification • Converts temperature to 1