LM27
www.ti.com SNIS124D – AUGUST 2002 – REVISED JULY 2013 LM27 SOT-23, ±3°C Accurate, 120°C-150°C Factory Preset Thermostat
Check for Samples: LM27 FEATURES DESCRIPTION The LM27 is a precision, single digital-output, lowpower 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 +120В°C to
+150В°C in 1В°C increments. The LM27 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 …