LTC1445_15 Datasheet, PDF (1/14 Pages) Linear Technology – Ultralow Power Quad Comparators with Reference

LTC1443/LTC1444/LTC1445
Ultralow Power Quad
Comparators with Reference
Features
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}
Applications
n _{Battery-Powered System Monitoring}
n _{Threshold Detectors}
n _{Window Comparators}
n _{Oscillator Circuits}
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Description
The LTC^®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.
Typical Application
Reference Settling Test Circuit
V_IN
3.4M
1%
1.21M
1%
5V
TO 8V
R1
10k
R2
2.4M
3
V⁺
5 IN A⁺ ₊
4 IN A^– _–
2 _OUT
14 HYST
8 REF
R3
430Ω
C1
1.0µF
LTC1445
+– _1.2V
V^–
9
144345 TA01
Reference Settling
8V
V⁺
5V
V_REF
OUT
2ms/DIV
144345 TA02
144345fe
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