LT4356-1/LT4356-2
Surge Stopper
FeA Description
n
Stops High Voltage Surges The LT 4356 surge stopper protects loads from high voltage
n
Adjustable Output Clamp Voltage transients. It regulates the output during an overvoltage
n
Overcurrent Protection event, such as load dump in automobiles, by controlling
n
Wide Operation Range: 4V to 80V the gate of an external N-channel MOSFET. The output is
n
Reverse Input Protection to 60V limited to a safe value thereby allowing the loads to con-
n
Low 7A Shutdown Current, LT4356-1 tinue functioning. The LT4356 also monitors the voltage
n
Adjustable Fault Timer drop between the V and SNS pins to protect against
CC
n
Controls N-channel MOSFET overcurrent faults. An internal amplifier limits the current
n
Shutdown Pin Withstands 60V to 100V sense voltage to 50mV. In either fault condition, a timer
n
Fault Output Indication is started inversely proportional to MOSFET stress. If the
n
Guaranteed Operation to 125C timer expires, the FLT pin pulls low to warn of an impend-
n
Auxiliary Amplifier for Level Detection Comparator or ing power down. If the condition persists, the MOSFET is
Linear Regulator Controller turned off. After a cool down period, the GATE pin pulls
n
Available in (4mm 3mm) 12-Pin DFN, up turning on the MOSFET again.
10-Pin MSOP or 16-Pin SO Packages
The auxiliary amplifier may be used as a voltage detection
comparator or as a linear regulator controller driving an
external PNP pass transistor.
ApplicA
n
Back-to-back FETs can be used in lieu of a Schottky diode
Automotive/Avionic Surge Protection
n
for reverse input protection, reducing voltage drop and
Hot Swap/Live Insertion
n
power loss. A shutdown pin reduces the quiescent current
High Side Switch for Battery Powered Systems
n
to less than 7A for the LT4356-1 during shutdown. The
Intrinsic Safety Applications
LT4356-2 differs from the LT4356-1 during shutdown by
L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and No
R and ThinSOT are trademarks of Analog Devices, Inc. All other trademarks are the
SENSE
reducing the quiescent current to 60A and keeping alive
property of their respective owners.
the auxiliary amplifier for uses such as an undervoltage
lockout or always-on regulator.
At l ApplicA
4A, 12V Overvoltage Output Regulator Overvoltage Protector Regulates Output at
27V During Transient
10m
IRLR2908 V
OUT
V
IN
12V
C = 6.8F
80V INPUT SURGE
TMR
I = 500mA
LOAD
10
102k
V
IN
V SNS GATE OUT
CC
20V/DIV
383k
FB
V
CC
SHDN
4.99k
12V
DC-DC 27V ADJUSTABLE CLAMP
+
IN LT4356DE
CONVERTER V
OUT
20V/DIV
100k
EN SHDN 12V
GND
UNDERVOLTAGE A FLT FAULT
OUT
GND TMR 4356 TA01b
100ms/DIV
4356 TA01
0.1F
4356fb
1
For more information www.linear.com/LT4356-1
tion ypic
tions
turesLT4356-1/LT4356-2
Absolute MAMMu rA (Notes 1 and 2)
V , SHDN ................................................ 60V to 100V Storage Temperature Range
CC
SNS ............................. V 30V or 60V to V + 0.3V DE12 .................................................. 65C to 125C
CC CC
OUT, A , FLT, EN ..................................... 0.3V to 80V MS, SO .............................................. 65C to 150C
OUT
GATE (Note 3) .................................0.3V to V + 10V Lead Temperature (Soldering, 10 sec)
OUT
+
FB, TMR, IN ................................................ 0.3V to 6V MS, SO ............................................................. 300C
+
A , EN, FLT, IN ..................................................3mA
OUT
Operating Temperature Range
LT4356C ................................................... 0C to 70C
LT4356I ................................................ 40C to 85C
LT4356H ............................................ 40C to 125C
pin conFA
TOP VIEW
TOP VIEW
+
TMR 1 16 IN
+
TMR 1 12 IN
FB 2 15 NC
TOP VIEW
FB 2 11 A
OUT
NC 3 14 A
OUT
10 TMR
FB 1
OUT 3 10 GND
9 GND
OUT 2
OUT 4 13 NC
13
8 EN
GATE 3
GATE 4 9 EN
GATE 5 12 GND
7 FLT
SNS 4
6 SHDN
SNS 5 8 FLT V 5
CC
NC 6 11 EN
MS PACKAGE
V 6 7 SHDN
CC
SNS 7 10 FLT
10-LEAD PLASTIC MSOP
V 8 9 SHDN
CC
T = 125C, = 120C/W
JMAX JA
DE PACKAGE
12-LEAD (4mm 3mm) PLASTIC DFN
S PACKAGE
T = 125C, = 43C/W
JMAX JA
16-LEAD PLASTIC SO
EXPOSED PAD (PIN 13) PCB GND CONNECTION OPTIONAL
T = 150C, = 100C/W
JMAX JA
4356fb
2
For more information www.linear.com/LT4356-1
tion igur
tings xi