LTC4211
1
4211fc
For more information www.linear.com/LTC4211
TYPICAL APPLICATION
FEATURES DESCRIPTION
Hot Swap Controller with
Multifunction Current Control
APPLICATIONS
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks of Linear
Technology Corporation. All other trademarks are the property of their respective owners.
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Allows Safe Board Insertion and Removal
from a Live Backplane
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Controls Supply Voltages from 2.5V to 16.5V
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Programmable Soft-Start with Inrush Current
Limiting, No External Gate Capacitor Required
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Faster Turn-Off Time Because No External Gate
Capacitor is Required
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Dual Level Overcurrent Fault Protection
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Programmable Response Time for Overcurrent
Protection (MS)
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Programmable Overvoltage Protection (MS)
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Automatic Retry or Latched Mode Operation (MS)
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High Side Drive for an External N-Channel FET
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User-Programmable Supply Voltage Power-Up Rate
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FB Pin Monitors V
OUT
and Signals RESET
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Glitch Filter Protects Against Spurious RESET Signal
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Electronic Circuit Breaker
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Hot Board Insertion and Removal (Either On
Backplane or On Removable Card)
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Industrial High Side Switch/Circuit Breaker
The LT C
®
4211 is a hot swap controller that allows a board
to be safely inserted and removed from a live backplane.
An internal high side switch driver controls the gate of an
external N-channel MOSFET for supply voltages ranging
from 2.5V to 16.5V. The LTC4211 provides soft-start and
inrush current limiting during the start-up period which
has a programmable duration.
Two on-chip current limit comparators provide dual level
overcurrent circuit breaker protection. The slow com
-
parator trips at V
CC
– 50mV and activates in 20µs (or is
programmed by an external filter capacitor, MS only).
The fast comparator trips at V
CC
– 150mV and typically
responds in 300ns.
The FB pin monitors the output supply voltage and signals
the RESET output pin. The ON pin signal turns the chip on
and off and can also be used for the reset function. The
MS package has FAULT and FILTER pins to provide addi-
tional functions like fault indication, autoretry or latch-off
modes, programmable current limit response time and
programmable
overvoltage protection using an external
Zener diode clamp.
Single Channel 5V Hot Swap Controller Power-Up Sequence
+
V
CC
SENSE
LTC4211
8
2
3 4
7 6
C
LOAD
V
OUT
5V
5A
GND
4211 TA01A
5
1
R4
15k
GATE
GNDTIMER
PCB CONNECTION SENSE
C
TIMER
10nF
FB
ON
SHORT
LONG
V
CC
5V
GND
LONG
Z1 = 1SMA10A OR SMAJ10A
* OPTIONAL
RESET
R2
10k
R1
20k
R
X
10Ω
R
SENSE
0.007Ω
PCB EDGE
CONNECTOR
(MALE)
M1
Si4410DY
Z1*
R3
36k
R5
10k
µP
LOGIC
RESET
C
X
100nF
BACKPLANE
CONNECTOR
(FEMALE)
4211 TA01b
2.5ms/DIV
NO C
LOAD
V
GATE
5V/DIV
V
RESET
5V/DIV
V
ON
1V/DIV
V
TIMER
1V/DIV