LTC4419
18V Dual Input Micropower
PowerPath Prioritizer
FEATURES DESCRIPTION
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Selects Highest Priority Valid Supply from Two Inputs The LTC 4419 is a dual input monolithic PowerPath
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Wide 1.8V to 18V Operating Range prioritizer with low operating current, that provides backup
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Internal Dual 2, 0.5A Switches switchover for keeping critical circuitry alive during brown
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Low 3.6A Operating Current out and power loss conditions. Unlike diode-OR products,
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Low 320nA V2 Current When V1 Connected to OUT little current is drawn from the inactive supply even if its
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Blocks Reverse and Cross Conduction Currents voltage is greater than the active supply.
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Reverse Supply Protection to 15V
Internal 2, current limited PMOS switches provide power
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V2 Freshness Seal/Ship Mode
path selection from a primary input (V1) or a backup input
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1.5% Accurate Adjustable Switchover Threshold
(V2) to the output. An adjustable voltage monitor set via
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Two Auxiliary 2.3% Accurate Voltage Comparators
an external resistive divider provides flexibility in setting
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Overcurrent and Thermal Protection
the V1 to V2 switchover threshold. When primary input V1
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Thermally Enhanced 10-Pin 3mm 3mm DFN
drops, the ADJ monitor input causes OUT to be switched
and 12-Lead Exposed Pad MSOP Packages
to V2. Fast non-overlap switchover circuitry prevents both
reverse and cross conduction while minimizing output
APPLICATIONS
droop.
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Low Power Battery Backup
The LTC4419 has two auxiliary comparators with open-
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Portable Equipment
drain outputs that provide flexible voltage monitoring. The
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Point-of-Sale (POS) Equipment
V2ON output indicates if V2 is powering OUT. Freshness
seal mode prevents V2 battery discharge during storage
or shipment.
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and
PowerPath and ThinSOT are trademarks of Analog Devices, Inc. All other trademarks are the
property of their respective owners.
TYPICAL APPLICATION
5V
Typical Switchover Waveforms
WALL
V1 OUT OUT
ADAPTER
C1
1M 1M 1M
10F
ADJ CMPOUT1 V1UV
237k
V2
2V/DIV
CMP1 CMPOUT2 V2UV
V1
121k
LTC4419
2V/DIV OUT
SWITCHOVER
C = 10F
OUT
V2 V2ON
V2ON THRESHOLD
I = 100mA
LOAD
+
7.4V
SWITCHOVER
4.02M
4419 TA01b
Li-Ion
THRESHOLD: V1 < 4V (V1 FALLING)
50s/DIV
CMP2
V1UV THRESHOLD: V1 < 4.4V (V1 FALLING)
GND
280k V2UV THRESHOLD: V2 < 6V (V2 FALLING)
4419 TA01a
4419fa
1
For more information www.linear.com/LTC4419LTC4419
ABSOLUTE MAXIMUM RATINGS (Notes 1, 2)
Input Supply Voltage Pin Currents (Note 2)
V1, V2 ......................................................15V to 24V ADJ, CMP1, CMP2, CMPOUT1, CMPOUT2,
OUT ....................................................... 0.3V to 24V V2ON .................................................................1mA
OUT V2 .................................................24V to 39V Operating Ambient Temperature Range
OUT V1 .................................................24V to 39V LTC4419C ................................................ 0C to 70C
Input Voltages LTC4419I .............................................40C to 85C
ADJ, CMP1, CMP2 (Note 3) .................. 0.3V to 24V Junction Temperature (Notes 4, 5) ........................ 125C
Output Voltages Storage Temperature Range .................. 65C to 150C
CMPOUT1, CMPOUT2, V2ON (Note 3) .. 0.3V to 24V Lead Temperature (Soldering, 10 sec)
MSOP Package .................................................300C
PIN CONFIGURATION
TOP VIEW
TOP VIEW
V1 1 12 V2
V1 1 10 V2
NC 2 11 NC
CMP1 2 9 CMP2
11 CMP1 3 13 10 CMP2
ADJ 3 8 OUT
GND GND
ADJ 4 9 OUT
GND 4 7 V2ON
GND 5 8 V2ON
CMPOUT1 5 6 CMPOUT2 CMPOUT1 6 7 CMPOUT2
MSE PACKAGE
DD PACKAGE
12-LEAD PLASTIC MSOP
10-LEAD (3mm 3mm) PLASTIC DFN
T = 125C, = 40C/W
JMAX JA
T = 125C, = 43C/W
JMAX JA
EXPOSED PAD (PIN 13) IS GND, MUST BE SOLDERED TO PCB
EXPOSED PAD (PIN 11) IS GND, MUST BE SOLDERED TO PCB