LTC4224-1/LTC4224-2
Compact Dual Low
Voltage Hot Swap Controller
FEATURES DESCRIPTION
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Allows Safe Board Insertion and Removal from a
The LTC 4224 Dual Low Voltage Hot Swap controller
Live Backplane
allows a board to be safely inserted and removed from a
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Controls Load Voltages from 1V to 6V
live backplane. It controls two supplies with external N-
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No Gate Components Required
channel MOSFETs and operates with one supply as low
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Adjustable Current Limit with Circuit Breaker
as 1V provided the other supply is 2.7V or greater. The
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Limits Peak Fault Current in 1s
LTC4224 can ramp up the supplies in any order and at
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No External Timing Capacitor Required
adjustable ramp rates. To minimize the number of external
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Adjustable Supply Voltage Power-Up Rate
components and PCB area, the gate capacitor is optional,
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Gate Drive for External N-channel MOSFET
all timing delays are generated internally, and the ON pins
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LTC4224-1: Latchoff After Fault
have integrated pull-up currents.
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LTC4224-2: Automatic Retry After Fault
Protection against overcurrent faults is provided by a fast-
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10-Lead MSOP and 3mm 2mm DFN Packages
acting current limit and timed circuit breakers. A FAULT pin
signals overcurrent faults. The LTC4224-1 remains off after
APPLICATIONS
a fault, while the LTC4224-2 automatically tries to apply
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Optical Networking
power again after a four second cool-down period.
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Low Voltage Hot Swap
L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. Hot Swap
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is a trademark of Linear Technology Corporation. All other trademarks are the property of their
Electronic Circuit Breakers
respective owners.
TYPICAL APPLICATION
Normal Power-Up Waveform
FDS6911
0.015
5V
5V
1A
0.010
3.3V
3.3V
V
OUT1
2A
5V/DIV
V
OUT2
V SENSE1 V SENSE2 GATE1 GATE2 5V/DIV
CC1 CC2
I
IN1
ON1
LTC4224 2A/DIV
LTC4224
ON2
FAULT GND GND
I
IN2
2A/DIV
C = 150F
LOAD
CONNECTOR PLUG-IN
422412 TA01b
0.5ms/DIV
CARD
422412 TA01a
422412fa
1LTC4224-1/LTC4224-2
(Notes 1, 2)
ABSOLUTE MAXIMUM RATINGS
Supply Voltage (V ) .................................. 0.3V to 9V Operating Temperature Range
CCn
Input Voltages LTC4224C ................................................ 0C to 70C
SENSEn, ONn ........................................... 0.3V to 9V LTC4224I.............................................. 40C to 85C
Output Voltages Storage Temperature Range .................. 65C to 150C
GATEn V (Note 4) .............................. 0.3V to 5V Lead Temperature Range (Soldering, 10 sec)
CC
FAULT ....................................................... 0.3V to 9V MSOP Package .................................................300C
PIN CONFIGURATION
TOP VIEW
TOP VIEW
SENSE1 1 10 SENSE2
SENSE1 1 10 SENSE2
V 2 9 V
CC1 CC2
V 2 9 V
CC1 CC2
11
GATE1 3 8 GATE2
GATE1 3 8 GATE2
FAULT 4 7 GND
FAULT 4 7 GND
ON1 5 6 ON2
ON1 5 6 ON2
MS PACKAGE
10-LEAD PLASTIC MSOP
DDB PACKAGE
T = 125C, = 160C/W
10-LEAD (3mm 2mm) PLASTIC DFN JMAX JA
T = 125C, = 43C/W
JMAX JA
EXPOSED PAD (PIN 11) PCB GND CONNECTION OPTIONAL
ORDER INFORMATION
LEAD FREE FINISH TAPE AND REEL PART MARKING* PACKAGE DESCRIPTION TEMPERATURE RANGE
LTC4224CDDB-1#PBF LTC4224CDDB-1#TRPBF LDTT 10-Lead (3mm 2mm) Plastic DFN 0C to 70C
LTC4224CDDB-2#PBF LTC4224CDDB-2#TRPBF LDNV 10-Lead (3mm 2mm) Plastic DFN 0C to 70C
LTC4224IDDB-1#PBF LTC4224IDDB-1#TRPBF LDTT 40C to 85C
10-Lead (3mm 2mm) Plastic DFN
LTC4224IDDB-2#PBF LTC4224IDDB-2#TRPBF LDNV 40C to 85C
10-Lead (3mm 2mm) Plastic DFN
LTC4224CMS-1#PBF LTC4224CMS-1#TRPBF LTDTV 10-Lead Plastic MSOP 0C to 70C
LTC4224CMS-2#PBF LTC4224CMS-2#TRPBF LTDNW 10-Lead Plastic MSOP 0C to 70C
LTC4224IMS-1#PBF LTC4224IMS-1#TRPBF LTDTV 10-Lead Plastic MSOP 40C to 85C
LTC4224IMS-2#PBF LTC4224IMS-2#TRPBF LTDNW 10-Lead Plastic MSOP 40C to 85C
Consult LTC Marketing for parts speci ed with wider operating temperature ranges. *The temperature grade is identi ed by a label on the shipping container.
Consult LTC Marketing for information on non-standard lead based nish parts.
For more information on lead free part marking, go to: