LTC1841/LTC1842/LTC1843
Ultralow Power Dual
Comparators with Reference
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FEATURES
DESCRIPTION
TheLTC®1841/LTC1842/LTC1843areultralowpowerdual
comparators with built-in reference (LTC1842/LTC1843).
The comparators feature less than 5.7µA supply current
over temperature, a 1.182V ±1% reference, program-
mable hysteresis and open-drain outputs that sink cur-
rent. The reference output can drive a bypass capacitor of
up to 0.01µF without oscillation.
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Ultralow Quiescent Current: 3.5µA Typ
Open-Drain Outputs Typically Sink
Greater Than 20mA
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Wide Supply Range: (LTC1841)
Single: 2V to 11V
Dual: ±1V to ±5.5V
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Input Voltage Range Includes the Negative Supply
Reference Output Drives 0.01
µF Capacitor
The LTC1841 operates from a single 2V to 11V supply or
a dual ±1V to ±5.5V supply. The LTC1842/LTC1843
operate from a single 2.5V to 11V supply or a dual ±1.25V
to ±5.5V supply. The LTC1842/LTC1843 hysteresis is
easily programmed by using two resistors and the HYST
pin. The comparators’ input operates from the negative
supply to within 1.3V of the positive supply. The compara-
tors’ output stage can typically sink greater than 20mA. By
eliminating the cross-conduction current that normally
happenswhenthecomparatorschangelogicstates,power
supply glitches are eliminated.
Adjustable Hysteresis
12µs Propagation Delay with 10mV Overdrive
No Current Spike When Switching
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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
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The LTC1841/LTC1842/LTC1843 are available in SO-8
packages.
, LTC and LT are registered trademarks of Linear Technology Corporation.
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TYPICAL APPLICATION
Single Li-Ion Cell to 5V Supply
LTC1843 Supply Current
vs Supply Voltage
1-CELL
+
L1
10µH
R6
25k
C1
100µF
Li-Ion
D1
5
BATTERY
7
T
= 25°C
A
6
7
T
R1
V
LTC1843
OUT B
CC
OUTPUT
5V
1.5M
–
V
SW
–
+
4
IN B
IN
4
3
2
1
0
600mA
LT1302-5
SHDN
PGND SENSE
Si9924DY
8
1
3
8
I
4
R2
100k
+
C2
100µF
V
GND
C
2
R
20k
1
+
3
6
IN A
C
R7
500k
+
–
–
OUT A
R3
1M
C
C
0.0µF
REF
LBO
1841/43 TA01
C1, C2: SANYO OS-CON
D1: MOTOROLA MBRS130LT3
L1: COILTRONICS CTX10-3
R4
20k
R5
1.1M
0
2
4
6
8
10
12
V
HYST
5
SUPPLY VOLTAGE (V)
2
1841/43 TA02
1