LT4356-1

Features:

` Stops High Voltage Surges
` Adjustable Output Clamp Voltage
` Overcurrent Protection
` Wide Operation Range: 4V to 80V
` Reverse Input Protection to 60V
` Low 7A Shutdown Current
` Adjustable Fault Timer
` Controls N-Channel MOSFET
` Shutdown Pin Withstands 60V to 100V
` Fault Output Indication
` Spare Amplifi er for Level Detection Comparator or Linear Regulator Controller
` Available in (4mm * 3mm) 12-Pin DFN or 10-Pin MSOP Packages


Application

· Automotive/Avionic Surge Protection
· Hot Swap/Live Insertion
· High Side Switch for Battery Powered Sys


Pinout




Specifications

V_CC, SHDN ................................................ 60V to 100V
SNS .............................V_CC 30V or 60V to V_CC + 0.3V
OUT, AOUT, FLT, EN ....................................0.3V to 80V
GATE (Note 3) ................................0.3V to V_OUT + 10V
F_B, TMR, IN+ ................................................0.3V to 6V
AOUT, EN, FLT .......................................................3mA
Operating Temperature Range
LT4356C-1 ...............................................     0 to 70
LT4356I-1 ............................................    40 to 85
LT4356H-1 .........................................    40 to 125
Storage Temperature Range
DE12 ..................................................     65to 125
MS .....................................................     65 to 150
Lead Temperature (Soldering, 10 sec, MS10) ....... 300


Description

The LT^®4356-1 surge stopper protects loads from high voltage transients. It regulates the output during an overvoltage event, such as load dump in automobiles, by controlling the gate of an external N-Channel MOSFET.

The output is limited to a safe value thereby allowing the loads to continue functioning. The LT4356-1 also monitors the voltage drop between the VCC and SNS pins to protect against overcurrent faults. An internal amplifi er limits the current sense voltage to 50mV. In either fault condition, a timer is started inversely proportional to MOSFET stress.

If the timer expires, the FLT pin pulls low to warn of an impending power down. If the condition persists, the MOSFET is turned off.

The spare amplifier of LT4356-1  may be used as a voltage detection comparator or as a linear regulator controller driving an external PNP pass transistor.

Back-to-back FETs can be used in lieu of a Schottky diode for reverse input protection, reducing voltage drop and power loss. A shutdown pin reduces the quiescent current to less than 7A during shutdown.