The Nest Learning Thermostat doesn’t support third-party temperature sensors, so unless you want to switch to ecobee ($249 for the thermostat, with an additional sensor included), this is the ...

No competing digital temperature sensor on the market today can achieve accuracy better than ±0.10°C. The AS6221 is housed in a WLCSP package with a footprint of just 1.5mm x 1mm, and draws 6µA ...

The ADT7484A and ADT7486A are simple, 1°C-accurate digital temperature sensors that monitor their own temperature, as well as one (ADT7484A) or two (ADT7486A) remote sensor diodes.

Chiseled for DDR3 memory-module applications, the CAT6095 12-bit, digital-output temperature sensor is available in an ultra-thin UDFN package measuring 2 mm x 3 mm and 0.55 mm in height.