LTC1642_15 Datasheet, PDF (1/16 Pages) Linear Technology – Hot Swap Controller

LTC1642
Hot Swap Controller
FEATURES
■ _{Adjustable Undervoltage and Overvoltage}
Protection
■ _{Foldback Current Limit}
■ _{Adjustable Current Limit Time-Out}
■ _{Protected Against Surges to 33V}
■ _{Single Channel NFET Driver}
■ _{Latch Off or Automatic Retry on Current Fault}
■ _{Driver for SCR Crowbar on Overvoltage}
■ _{Adjustable Reset Timer}
■ _{Reference Output with Uncommitted Comparator}
■ _{16-Pin SSOP Package}
U
APPLICATIO S
■ _{Hot Board Insertion}
■ _{Electronic Circuit Breaker}
■ _InfiniBand^TM _Systems
DESCRIPTIO
The LTC^®1642 is a 16-pin Hot Swap^TM controller that
allows a board to be safely inserted and removed from a
live backplane. Using an external N-Channel pass transis-
tor, the board supply voltage can be ramped up at an
adjustable rate. A high side switch driver controls the
N-Channel gate for supply voltages above 2.97V.
The SENSE pin allows foldback limiting of the load current,
with circuit breaker action after an adjustable delay time.
The delay allows the part to power-up in current limit. The
CRWBR output can be used to trigger an SCR for crowbar
protection of the load if the input supply exceeds an
adjustable threshold. The RESET output can generate a
system reset with adjustable delay when the supply
voltage falls below an adjustable threshold. The ON
pin cycles the board power. The LTC1642 is available in
the 16-pin SSOP package.
, LTC and LT 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 APPLICATIO
BACKPLANE
12V
PLUG-IN CARD
(SHORT PIN) _110k
1%
0.010Ω
5%
FDS6630A
100Ω
5%
1N4705
18V
330Ω
5%
0.047µF
UV = 10.8V
2.87k
1%
OV = 13.2V
11.3k
1%
GND
V_CC
SENSE
GATE
RESET
FB
ON
LTC1642
FAULT
OV
GND BRK TMR
RST TMR
CRWBR
COMP^–
COMP⁺
COMPOUT
REF
2N2222
0.33µF
0.33µF
0.1µF
0.01µF
12V
+
AT 2.5A
C_LOAD
107k
1%
POWER-GOOD = 11.4V
MCR
12DC
13k
1%
1642 TA01
1642fb
1