1 Features
1• Internal Comparator With Pin Programmable 2°C
or 10°C Hysteresis
• No External Components Required
• Open-Drain or Push-Pull Digital Output; Supports
CMOS Logic Levels
• Internal Temperature Sensor With VTEMP Output
Pin
• VTEMP Output Allows After-Assembly System
Testing
• Internal Voltage Reference and DAC for Trip-Point
Setting
• Currently Available in 5-pin SOT-23 Plastic
Package
• Excellent Power Supply Noise Rejection
• UL Recognized Component
• Key Specifications
– Power Supply Voltage 2.7 V to 5.5 V
– Power Supply Current
40 μA (Maximum) 16 μA (Typical)
– Hysteresis Temperature 2°C or 10°C (Typical)

2 Applications
• Microprocessor Thermal Management
• Appliances
• Portable Battery Powered Systems
• Fan Control
• Industrial Process Control
• HVAC Systems
• Remote Temperature Sensing
• Electronic System Protection

3 Description
The LM26 is a precision, single digital-output, low-
power thermostat comprised of an internal reference,
DAC, temperature sensor and comparator. Utilizing
factory programming, it can be manufactured with
different trip points as well as different digital output
functionality. The trip point (TOS) can be preset at the
factory to any temperature in the range of −55°C to
110°C in 1°C increments. The LM26 has one digital output (OS/OS/US/US), one digital input (HYST) and
one analog output (VTEMP). The digital output stage
can be preset as either open-drain or push-pull. In
addition, it can be factory programmed to be active
HIGH or LOW. The digital output can be factory
programmed to indicate an over temperature
shutdown event (OS or OS) or an under temperature shutdown event (US or US). When preset as an
overtemperature shutdown (OS) it will go LOW to
indicate that the die temperature is over the internally
preset TOS and go HIGH when the temperature goes below (TOS–THYST). Similarly, when preprogrammed
as an undertemperature shutdown (US) it will go
HIGH to indicate that the temperature is below TUS
and go LOW when the temperature is above
(TUS+THYST). The typical hysteresis, THYST, can be set to 2°C or 10°C and is controlled by the state of the
HYST pin. A VTEMP analog output provides a voltage
that is proportional to temperature and has a −10.82
mV/°C output slope.
Available parts are detailed in the Device Comparison
Table. For other part options, contact a Texas
Instruments Distributor or Sales Representative for information on minimum order qualification. The
LM26 is currently available in a 5-lead SOT-23
package.