LT4356MP-1/LT4356MP-2 Surge Stopper FEATURES DESCRIPTION n Stops High Voltage Surges The LT 4356 surge stopper protects loads from high volt- n Adjustable Output Clamp Voltage age transients. It regulates the output during an overvolt- n Overcurrent Protection age event, such as load dump in automobiles, by control- n Wide Operation Range: 4V to 80V ling the gate of an external N-channel MOSFET. The output n Reverse Input Protection to 60V is limited to a safe value thereby allowing the loads to n Low 7A Shutdown Current, LT4356-1 continue functioning. The LT4356MP also monitors the n Adjustable Fault Timer voltage drop between the V and SNS pins to protect CC n Controls N-Channel MOSFET against overcurrent faults. An internal amplifier limits the n Shutdown Pin Withstands 60V to 100V current sense voltage to 50mV. In either fault condition, a n Fault Output Indication timer is started inversely proportional to MOSFET stress. n Guaranteed Operation 55C to 125C If the timer expires, the FLT pin pulls low to warn of an n Auxiliary Amplifier for Level Detection Comparator or impending power-down. If the condition persists, the Linear Regulator Controller MOSFET is turned off. After a cooldown period, the GATE n Available in 10-Pin MSOP or 16-Pin SO Packages pin pulls up turning on the MOSFET again. The auxiliary amplifier may be used as a voltage detection comparator or as a linear regulator controller driving an APPLICATIONS external PNP pass transistor. n Automotive/Avionic Surge Protection n Hot Swap/Live Insertion Back-to-back FETs can be used in lieu of a Schottky diode n High Side Switch for Battery Powered Systems for reverse input protection, reducing voltage drop and n Intrinsic Safety Applications power loss. A shutdown pin reduces the quiescent current to less than 7A for the LT4356-1 during shutdown. The L, LT, LTC, LTM, Linear Technology and the Linear logo are registered trademarks and NoR and ThinSOT are trademarks of Analog Devices, Inc. All other trademarks are the SENSE LT4356-2 differs from the LT4356-1 during shutdown by property of their respective owners. reducing the quiescent current to 60A and keeping alive the auxiliary amplifier for uses such as an undervoltage lockout or always-on regulator. TYPICAL APPLICATION 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 20V/DIV CC 383k FB V CC SHDN 12V 4.99k 27V ADJUSTABLE CLAMP + DC-DC IN LT4356S V OUT CONVERTER 20V/DIV 100k 12V EN SHDN GND UNDERVOLTAGE A FLT FAULT OUT 4356mp12 TA01b GND TMR 100ms/DIV 4356mp12 TA01 0.1F 4356mp12fc 1 For more information www.linear.com/LT4356MP-1LT4356MP-1/LT4356MP-2 ABSOLUTE MAXIMUM RATINGS (Notes 1 and 2) V , SHDN ................................................ 60V to 100V Operating Temperature Range CC SNS ............................. V 30V or 60V to V + 0.3V LT4356M ............................................ 55C to 125C CC CC OUT, A , FLT, EN ..................................... 0.3V to 80V Storage Temperature Range OUT GATE (Note 3) .................................0.3V to V + 10V MS, SO .............................................. 65C to 150C OUT + FB, TMR, IN ................................................ 0.3V to 6V Lead Temperature (Soldering, 10 sec) + A , EN, FLT, IN .................................................. 3mA MS, SO .............................................................300C OUT PIN CONFIGURATION TOP VIEW + TMR 1 16 IN FB 2 15 NC TOP VIEW NC 3 14 A OUT FB 1 10 TMR OUT 2 9 GND OUT 4 13 NC GATE 3 8 EN GATE 5 12 GND SNS 4 7 FLT V 5 6 SHDN CC NC 6 11 EN MS PACKAGE SNS 7 10 FLT 10-LEAD PLASTIC MSOP V 8 9 SHDN T = 125C, = 160C/W CC JMAX JA S PACKAGE 16-LEAD PLASTIC SO T = 150C, = 100C/W JMAX JA