
1
ASTEC Semiconductor
AS273
Over-Temperature Detector
Features
Programmable to three different
over-temperature thresholds
2.5 V temperature compensated
bandgap reference trimmed to 1%
Open collector output goes low
on over-temp condition
±3C temperature accuracy
Reference shunt current serves to
program over-temp threshold
Available with 5C or 10C of
temperature hysteresis
Available in a wide range of over-
temp thresholds to fit most
temperature monitoring
applications
Now available in the SOT-223 for
improved substrate temperature
sensing
Description
The AS273 is a series of programmable over-temperature
detectors. Each is internally composed of a precision 2.5 V
shunt reference, a proportional-to-absolute temperature
thermal sensor, a comparator with controlled hysteresis, and
an open collector output that indicates an over-temp condi-
tion. The threshold for the over-temp signal can be set to any
of three values on a given part by controlling the magnitude
of the reference shunt current.
The AS273 has an excellent absolute temperature accuracy
of ±3C for each of the three over-temp thresholds. The low
power dissipation minimizes any temperature sensing errors
due to self-heating. There is either 5C or 10C of tempera-
ture hysteresis to prevent bouncing when an over-temp con-
dition is removed.
The packaging options available with the AS273 make it
appealing to a wide variety of temperature-sensing applica-
tions. The TO-92 package can be mechanically clamped to a
heat sink to monitor the temperature of power devices. The
8L-SOIC and SOT-223 surface mount packages allow for
temperature sensing in high component density applications.
SEMICONDUCTOR
Pin Configuration Top view
OUT
TO-92 (LP)
SOT-223 (G)
GROUND
V
REF
OUT
GROUND
V
REF
SOIC (D)
VREF
DO NOT USE
GROUND
OUT
N/C
1
2
3
4
8
7
6
5