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LTC1443/LTC1444/LTC1445
1
144345fe
Typical applicaTion
DescripTion
Ultralow Power Quad
Comparators with Reference
The LT C
®
1443/LTC1444/LTC1445 are ultralow power quad
comparators with a built-in reference. The comparators
feature less than 8.5µA supply current over temperature,
an internal reference (1.182V ±1% for LTC1443 or 1.221V
±1% for LTC1444/LTC1445), programmable hysteresis
(LTC1444/LTC1445) and TTL/CMOS output (LTC1443/
LTC1445) that sinks and sources current (open-drain
output for LTC1444). 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 (LTC1443). Comparator
hysteresis is easily programmable using two resistors and
the HYST pin (LTC1444/LTC1445). Each comparator’s
input operates from the negative supply to within 1.3V of
the positive supply. The LTC1443/LTC1445 comparator
output stage can continuously source up to 40mA. By
eliminating the cross-conducting current that normally
happens when the comparator changes logic states, power
supply glitches are eliminated.
The LTC1443/LTC1444/LTC1445 are available in the
16-pin SO, PDIP and DFN packages.
FeaTures
applicaTions
n
Ultralow Quiescent Current: 8.5µA Max
n
Reference Output Drives 0.01µF Capacitor
n
Adjustable Hysteresis (LTC1444/LTC1445)
n
Wide Supply Range
Single: 2V to 11V
Dual: ±1V to ±5.5V
n
Input Voltage Range Includes the Negative Supply
n
TTL/CMOS Compatible Outputs
n
Propagation Delay: 12µs (Typ) (10mV Overdrive)
n
No Crowbar Current
n
40mA Continuous Source Current
n
Pin Compatible Upgrades for MAX924 (LTC1443)
n
Low Profile (5mm × 4mm × 0.8mm) DFN Package
n
Battery-Powered System Monitoring
n
Threshold Detectors
n
Window Comparators
n
Oscillator Circuits
Reference Settling Test Circuit
–
+
IN A
+
5
OUT
V
+
1.2V
R1
10k
R3
430Ω
R2
2.4M
C1
1.0µF
IN A
–
HYST
REF
4
14
8
5V
TO 8V
144345 TA01
LTC1445
3
9
2
1.21M
1%
3.4M
1%
V
IN
+
–
V
–
Reference Settling
L, LT , LT C , LT M , Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
V
+
8V
5V
V
REF
144345 TA02
OUT
2ms/DIV
2mV/DIV
