LTC1540
Nanopower Comparator
with Reference
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FEATURES
DESCRIPTION
The LTC®1540 is an ultralow power, single comparator
with built-in reference. The comparator’s features
include less than 0.6µA supply current over the commer-
cial temperature range, a 1.182V ±2% reference, pro-
grammable hysteresis and TTL/CMOS outputs that sink
and source current. The reference output can drive a
bypass capacitor of up to 0.01µF without oscillation.
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Ultralow Quiescent Current: 0.3
µ
A Typ
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Reference Output Drives 0.01
Adjustable Hysteresis
µF Capacitor
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Wide Supply Range: 2V to 11V
Input Voltage Range Includes the Negative Supply
Reference Output Sources Up to 1mA
TTL/CMOS Compatible Outputs
60µs Propagation Delay with 10mV Overdrive
No Crowbar Current
40mA Continuous Source Current
Pin Compatible with LTC1440, MAX921, MAX931
The comparator operates from a single 2V to 11V supply
or a dual ±1V to ±5.5V supply. Comparator hysteresis is
easily programmed by using two resistors and the HYST
pin. Each comparator’s input operates from the negative
supply to within 1.3V of the positive supply. The compara-
tor output stage can continuously source up to 40mA. By
eliminating the cross-conducting current that normally
occur when the comparator changes logic states, power
supply glitches are eliminated.
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APPLICATIONS
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Battery-Powered System Monitoring
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Threshold Detectors
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Window Comparators
Oscillator Circuits
The LTC1540 is available in the 8-pin MSOP and SO
packages.
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, LTC and LT are registered trademarks of Linear Technology Corporation.
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TYPICAL APPLICATION
Nanopower 2.9V VCC Threshold Detector
LTC1540 Supply Current vs Temperature
3.3V
0.50
+
7
V
V
= 5V
R1
–
+
= GND = 0V
4.32M
0.45
0.40
0.35
0.30
0.25
0.20
0.15
V
LTC1540
1%
+
–
3
4
5
6
IN
+
–
8
R2
3M
1%
OUT
IN
HYST
REF
–
–40 –20
20
40
0
TEMPERATURE (°C)
60
80
100
GND
V
2
1
1540 • TA02
1540
• TA01
1