LTC4224-1_15 Datasheet, PDF (1/16 Pages) Linear Technology – Compact Dual Low Voltage Hot Swap Controller

LTC4224-1/LTC4224-2
Compact Dual Low
Voltage Hot Swap Controller
FEATURES
n _{Allows Safe Board Insertion and Removal from a}
Live Backplane
n _{Controls Load Voltages from 1V to 6V}
n _{No Gate Components Required}
n _{Adjustable Current Limit with Circuit Breaker}
n _{Limits Peak Fault Current in ≤1μs}
n _{No External Timing Capacitor Required}
n _{Adjustable Supply Voltage Power-Up Rate}
n _{Gate Drive for External N-channel MOSFET}
n _{LTC4224-1: Latchoff After Fault}
n _{LTC4224-2: Automatic Retry After Fault}
n _{10-Lead MSOP and 3mm × 2mm DFN Packages}
APPLICATIONS
n _{Optical Networking}
n _{Low Voltage Hot Swap}
n _{Electronic Circuit Breakers}
DESCRIPTION
The LTC^®4224 Dual Low Voltage Hot Swap™ controller
allows a board to be safely inserted and removed from a
live backplane. It controls two supplies with external N-
channel MOSFETs and operates with one supply as low
as 1V provided the other supply is 2.7V or greater. The
LTC4224 can ramp up the supplies in any order and at
adjustable ramp rates. To minimize the number of external
components and PCB area, the gate capacitor is optional,
all timing delays are generated internally, and the ON pins
have integrated pull-up currents.
Protection against overcurrent faults is provided by a fast-
acting current limit and timed circuit breakers. A FAULT pin
signals overcurrent faults. The LTC4224-1 remains off after
a fault, while the LTC4224-2 automatically tries to apply
power again after a four second cool-down period.
L, LT, LTC and LTM are registered trademarks of Linear Technology Corporation. Hot Swap
is a trademark of Linear Technology Corporation. All other trademarks are the property of their
respective owners.
TYPICAL APPLICATION
FDS6911
0.015Ω
5V
5V
1A
0.010Ω
3.3V
3.3V
2A
V_CC1 SENSE1 V_CC2 SENSE2 GATE1 GATE2
ON1
LTC4224
LTC4224
ON2
FAULT
GND
GND
CONNECTOR PLUG-IN
CARD
422412 TA01a
Normal Power-Up Waveform
V_OUT1
5V/DIV
V_OUT2
5V/DIV
I_IN1
2A/DIV
I_IN2
2A/DIV
0.5ms/DIV
C_LOAD = 150μF
422412 TA01b
422412fa
1