SetPoint typeResistor ProgrammableSetPoint value (deg C)-40 to 160Operating temperature range (C)-50 to 125, -50 to 150, -50 to 160Accuracy over temp range (Max) (C)1.3Sensor gain (mV/Deg C)-5.2 to 12.9Output typeOpen Drain, Push PullSupply voltage (Min) (V)2.4Supply voltage (Max) (V)5.5Supply current (Typ) (uA)24Comparator channels (#)1FeaturesBuilt-in hysteresisRatingAutomotiveInterface typeAnalog output, Switchopen-in-newFind other Temperature switches
The LM57-Q1 device is a
precision, dual-output, temperature switch with analog temperature sensor output for wide
temperature applications such as
automotive grade. The trip temperature (TTRIP) is selected from 256
possible values in the range of –40°C to 160°C.
The VTEMP is a class AB analog voltage
output that is proportional to temperature with a programmable negative temperature coefficient
(NTC). Two external 1% resistors set the TTRIP and
VTEMP slope. The digital and analog outputs enable protection and monitoring
of system thermal events.
Built-in thermal hysteresis (THYST) prevents the digital outputs
from oscillating. The TOVER and
TOVER digital outputs will assert when the die temperature
exceeds TTRIP and will de-assert when the temperature falls below a
temperature equal to TTRIP minus THYST.
TOVER is active-high with a push-pull structure.
TOVER is active-low with an open-drain structure. Tying
TOVER to TRIP-TEST will latch the output after it trips. The output can be
cleared by forcing TRIP-TEST low. Driving the TRIP-TEST high will assert the digital outputs. A
processor can check the state of TOVER or
TOVER, confirming they changed to an active state. This allows
for in situ verification that the comparator and output circuitry are functional after system
assembly. When TRIP-TEST is high, the trip-level reference voltage appears at the
VTEMP pin. The system could then use this voltage to calculate the threshold
of the LM57-Q1.