LTC1440/LTC1441/LTC1442
Ultralow Power Single/Dual
Comparator with Reference
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DESCRIPTIO
FEATURES
The LTC®1440/LTC1441/LTC1442 are ultralow power
single and dual comparators with built-in references. The
comparators feature less than 3.7µA supply current over
temperature (LTC1440), a 1.182V ±1% reference, pro-
grammablehysteresis(LTC1440/LTC1442)andTTL/CMOS
outputsthatsinkandsourcecurrent. Thereferenceoutput
can drive a bypass capacitor of up to 0.01µF without
oscillation.
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Ultralow Quiescent Current: 2.1
µ
A Typ (LTC1440)
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Reference Output Drives 0.01
µF Capacitor
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Adjustable Hysteresis (LTC1440/LTC1442)
Wide Supply Range:
Single: 2V to 11V
Dual: ±1V to ±5.5V
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■
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Input Voltage Range Includes the Negative Supply
TTL/CMOS Compatible Outputs
12µs Propagation Delay with 10mV Overdrive
No Crowbar Current
40mA Continuous Source Current
Pin Compatible Upgrades for MAX921/922/923
3mm x 3mm x 0.75mm DFN Package (LTC1440)
The comparators operate from a single 2V to 11V supply
or a dual ±1V to ±5.5V supply (LTC1440). Comparator
hysteresis is easily programmed by using two resistors
andtheHYSTpin(LTC1440/LTC1442).Eachcomparator’s
input operates from the negative supply to within 1.3V of
the positive supply. The comparator output stage can
continuously source up to 40mA. By eliminating the
cross-conductingcurrentthatnormallyhappenswhenthe
comparatorchangeslogicstates,thepowersupplyglitches
are eliminated.
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APPLICATIO S
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Battery-Powered System Monitoring
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Threshold Detectors
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Window Comparators
Oscillator Circuits
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The LTC1440 is available in 8-pin PDIP, SO, MSOP and
DFN packages. The LTC1441/LTC1442 are available in
8-pin PDIP and SO packages.
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
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TYPICAL APPLICATIO
Micropower 2.9V V Threshold Detector
CC
LTC1440 Supply Current vs Temperature
3.3V
5.0
+
V
V
= 5V
–
7
= GND = 0V
4.5
4.0
3.5
3.0
2.5
2.0
1.5
R1
1.65M
1%
+
V
+
–
3
4
5
6
IN
IN
+
–
8
R2
1.13M
1%
OUT
HYST
REF
LTC1440
40
0
TEMPERATURE (°C)
80 100
–40 –20
20
60
–
GND
1
V
1440/1/2 TA02
2
1440 TA01
144012fd
1