Texas Instruments Temperature Sensor, Open Drain Output, Surface Mount, ±4°C, 5 Pins

The LM26/27 series of single output thermostats are composed of an internal reference, DAC, temperature sensor and comparator. In addition to the single digital output, the thermostats also have an analogue output and a digital input.
Applications include thermal management within microprocessing, remote temperature sensing, protection within electronic systems, fan control, HVAC, industrial process control and portable battery powered systems.

Features;
Internal temperature sensor
Excellent noise rejection
Internal voltage reference and DAC for trip-point setting