A digital temperature sensor is said to allow up to 27 addresses on one I²C communication bus. Combinations on the DS75LX from Maxim Integrated Products, Sunnyvale, Calif., (maximic.com) are made possible by three dedicated address pins that can be in one of three states: tied to GND, tied to V_DD, or left floating. Competing devices usually tie three address pins to GND or V_DD, for only eight addresses.

The sensor operates on 1.7 to 3.7 V and can be connected directly to low-voltage supply rails. The factory-calibrated unit has an accuracy of ±2.0°C (max) over its entire supply-voltage range and a temperature range of -25 to 100°C. Its accuracy is ±3.0°C over its operating-temperature range of -55 to 125°C. User selectable 9, 10, 11, or 12-bit temperature readings translate to resolutions between 0.5°C (9 bit) and 0.0625°C (12 bit). The temperature sensor also has thermostat functions with user-defined trip points that allow customizing the threshold temperature and output hysteresis.