herunterladen

1
LTC1841/LTC1842/LTC1843
Ultralow Power Dual
Comparators with Reference
LTC1843 Supply Current
vs Supply Voltage
SUPPLY VOLTAGE (V)
0
SUPPLY CURRENT (µA)
3
4
5
8
1841/43 TA02
2
1
0
2
4
6
10
12
T
A
= 25°C
The LTC
®
1841/LTC1842/LTC1843 are ultralow power dual
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.
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
happens when the comparators change logic states, power
supply glitches are eliminated.
The LTC1841/LTC1842/LTC1843 are available in SO-8
packages.
FEATURES
DESCRIPTION
U
■
Ultralow Quiescent Current: 3.5
µ
A Typ
■
Open-Drain Outputs Typically Sink
Greater Than 20mA
■
Wide Supply Range: (LTC1841)
Single: 2V to 11V
Dual: ±1V to ±5.5V
■
Input Voltage Range Includes the Negative Supply
■
Reference Output Drives 0.01
µ
F Capacitor
■
Adjustable Hysteresis
■
12µs Propagation Delay with 10mV Overdrive
■
No Current Spike When Switching
R4
20k
R
C
20k
C
C
0.0µF
R7
500k
OUTPUT
5V
600mA
LBO
R5
1.1M
R3
1M
R2
100k
R1
1.5M
C1
100µF
1-CELL
Li-Ion
BATTERY
R6
25k
7
8
67
D1
L1
10µH
48
3
12
1
6
C1, C2: SANYO OS-CON
D1: MOTOROLA MBRS130LT3
L1: COILTRONICS CTX10-3
25
1841/43 TA01
3
4
+
C2
100µF
Si9924DY
+
–
+
–
+
V
CC
OUT B
LTC1843
OUT A
REF
V
–
HYST
IN A
+
IN B
–
V
IN
SW
LT1302-5
SHDN
PGND
I
T
SENSE
V
C
GND
TYPICAL APPLICATION
U
Single Li-Ion Cell to 5V Supply
, LTC and LT are registered trademarks of Linear Technology Corporation.
APPLICATIONS
U
■
Battery-Powered System Monitoring
■
Threshold Detectors
■
Window Comparators
■
Oscillator Circuits
Verzeichnis