LTC1440/LTC1441/LTC1442
Ultralow Power Single/Dual
Comparator with Reference
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DESCRIPTIO
FEATURES
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Ultralow Quiescent Current: 2.1µA Typ (LTC1440)
Reference Output Drives 0.01µF Capacitor
Adjustable Hysteresis (LTC1440/LTC1442)
Wide Supply Range:
Single: 2V to 11V
Dual: ±1V to ±5.5V
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)
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APPLICATIO S
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Battery-Powered System Monitoring
Threshold Detectors
Window Comparators
Oscillator Circuits
, LT, LTC and LTM are registered trademarks of Linear Technology Corporation.
All other trademarks are the property of their respective owners.
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, programmable hysteresis (LTC1440/LTC1442) and TTL/CMOS
outputs that sink and source current. The reference output
can drive a bypass capacitor of up to 0.01µF without
oscillation.
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
and the HYST pin (LTC1440/LTC1442). Each comparator’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-conducting current that normally happens when the
comparator changes logic states, the power supply glitches
are eliminated.
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.
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TYPICAL APPLICATIO
Micropower 2.9V VCC Threshold Detector
LTC1440 Supply Current vs Temperature
3.3V
5.0
R2
1.13M
1%
7
4.5
V+
3 IN +
+
8
4 IN–
–
5 HYST
V + = 5V
V – = GND = 0V
4.0
3.5
3.0
2.5
2.0
LTC1440
6 REF
OUT
SUPPLY CURRENT (µA)
R1
1.65M
1%
1.5
–40 –20
V–
2
GND
1
40
20
60
0
TEMPERATURE (°C)
80
100
1440/1/2 TA02
1440 TA01
144012fd
1
