LT4363 - High Voltage Surge Stopper with Current Limit


  • Withstands Surges Over 80V with VCC Clamp
  • Wide Operating Voltage Range: 4V to 80V
  • Adjustable Output Clamp Voltage
  • Fast Overcurrent Limit: Less Than 5μs
  • Reverse Input Protection to –60V
  • Adjustable UV/OV Comparator Thresholds
  • Low 7μA Shutdown Current
  • Shutdown Pin Withstands –60V to 100V
  • Adjustable Fault Timer
  • Controls N-Channel MOSFET
  • Less Than 1% Retry Duty Cycle During Faults, LT4363-2
  • Available in 12-Pin (4mm × 3mm) DFN, 12-Pin MSOP or 16-Pin SO Packages

Typical Application

LT4363 Typical Application
LT4363 Typical Application


The LT®4363 surge stopper protects loads from high voltage transients. It regulates the output during an overvoltage event, such as load dump in vehicles, by controlling the gate of an external N-channel MOSFET. The output is limited to a safe value allowing the loads to continue functioning. The LT4363 also monitors the voltage drop between the SNS and OUT pins to protect against overcurrent faults. An internal amplifier limits the voltage across the current sense resistor to 50mV. In either fault condition, a timer is started inversely proportional to MOSFET stress. Before 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 LT4363-1 remains off until reset whereas the LT4363-2 restarts after a cool down period.

Two precision comparators can monitor the input supply for overvoltage (OV) and undervoltage (UV) conditions. When the potential is below the UV threshold, the external MOSFET is kept off. If the input supply voltage is above the OV threshold, the MOSFET is not allowed to turn back on. Back-to-back MOSFETs 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 7μA during shutdown.


For complete and up to date package information and drawings, please refer to our packaging page

DFN-12, MS-12, SO-16

LT4363 Package Drawing
LT4363 Package Drawing
LT4363 Package Drawing
LT4363 Package Drawing
LT4363 Package Drawing
LT4363 Package Drawing

Order Info

Package Variations and Pricing

Part Number Package Pins Temp Price (1-99) Price (1k)* RoHS Data
LT4363CDE-1#PBF DFN 12 C $3.54 $2.48 View
LT4363CDE-1#TRPBF DFN 12 C $2.54 View
LT4363CDE-2#PBF DFN 12 C $3.54 $2.48 View
LT4363CDE-2#TRPBF DFN 12 C $2.54 View
LT4363CMS-1#PBF MSOP 12 C $3.54 $2.48 View
LT4363CMS-1#TRPBF MSOP 12 C $2.54 View
LT4363CMS-2#PBF MSOP 12 C $3.54 $2.48 View
LT4363CMS-2#TRPBF MSOP 12 C $2.54 View
LT4363CS-1#PBF SO 16 C $3.54 $2.48 View
LT4363CS-1#TRPBF SO 16 C $2.54 View
LT4363CS-2#PBF SO 16 C $3.54 $2.48 View
LT4363CS-2#TRPBF SO 16 C $2.54 View
LT4363HDE-1#PBF DFN 12 H $4.49 $3.14 View
LT4363HDE-1#TRPBF DFN 12 H $3.20 View
LT4363HDE-2#PBF DFN 12 H $4.49 $3.14 View
LT4363HDE-2#TRPBF DFN 12 H $3.20 View
LT4363HMS-1#PBF MSOP 12 H $4.49 $3.14 View
LT4363HMS-1#TRPBF MSOP 12 H $3.20 View
LT4363HMS-2#PBF MSOP 12 H $4.49 $3.14 View
LT4363HMS-2#TRPBF MSOP 12 H $3.20 View
LT4363HS-1#PBF SO 16 H $4.49 $3.14 View
LT4363HS-1#TRPBF SO 16 H $3.20 View
LT4363HS-2#PBF SO 16 H $4.49 $3.14 View
LT4363HS-2#TRPBF SO 16 H $3.20 View
LT4363IDE-1#PBF DFN 12 I $4.07 $2.85 View
LT4363IDE-1#TRPBF DFN 12 I $2.91 View
LT4363IDE-2 DFN 12 I $4.07 $2.85 View
LT4363IDE-2#PBF DFN 12 I $4.07 $2.85 View
LT4363IDE-2#TRPBF DFN 12 I $2.91 View
LT4363IMS-1#PBF MSOP 12 I $4.07 $2.85 View
LT4363IMS-1#TRPBF MSOP 12 I $2.91 View
LT4363IMS-2#PBF MSOP 12 I $4.07 $2.85 View
LT4363IMS-2#TRPBF MSOP 12 I $2.91 View
LT4363IS-1#PBF SO 16 I $4.07 $2.85 View
LT4363IS-1#TRPBF SO 16 I $2.91 View
LT4363IS-2#PBF SO 16 I $4.07 $2.85 View
LT4363IS-2#TRPBF SO 16 I $2.91 View
LT4363MPMS-1#PBF MSOP 12 MP $10.63 $7.44 View
LT4363MPMS-1#TRPBF MSOP 12 MP $7.50 View
LT4363MPMS-2#PBF MSOP 12 MP $10.63 $7.44 View
LT4363MPMS-2#TRPBF MSOP 12 MP $7.50 View
LT4363MPS-1#PBF SO 16 MP $10.63 $7.44 View
LT4363MPS-1#TRPBF SO 16 MP $7.50 View
LT4363MPS-2#PBF SO 16 MP $10.63 $7.44 View
LT4363MPS-2#TRPBF SO 16 MP $7.50 View
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* The USA list pricing shown is for BUDGETARY USE ONLY, shown in United States dollars (FOB USA per unit for the stated volume), and is subject to change. International prices may differ due to local duties, taxes, fees and exchange rates. For volume-specific price or delivery quotes, please contact your local Linear Technology sales office or authorized distributor.

Demo Boards

Linear Technology offers many demo boards free of charge to qualified customers. Contact your local sales office or distributor to inquire about a demo board. Certain demo boards are also available for sale via credit card on this website. Demo boards are for evaluation purposes only. It remains the customer’s responsibility to verify proper and reliable operation in the actual end application.

Part Number Description Price Documentation
DC1935A-A LT4363-1 Demo Board: High Voltage Surge Stopper with Current Limit, Latch-Off Version $75.00
DC1935A-B LT4363-2 Demo Board: High Voltage Surge Stopper with Current Limit, Auto-Retry Version $75.00
DC2062A-A LT4363IDE-1 Demo Board: 12V System ISO-7637-2 Surge Stopper, Latch-Off Version $75.00
DC2062A-B LT4363IDE-2 Demo Board: 12V System ISO-7637-2 Surge Stopper, Auto-Retry Version $75.00
DC2150A-C 28V, 5A MIL-STD-1275D Surge Stopper [Featuring LTC4366HTS8-2 and LT4363HS-2] $150.00
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Click here to view our complete list of demo boards


  • Automotive/Avionic Surge Protection
  • Hot Swap™/Live Insertion
  • High Side Switch for Battery Powered Systems
  • Intrinsic Safety Applications

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