Features and Benefits
- Stops High Voltage Surges
- Adjustable Output Clamp Voltage
- Overcurrent Protection
- Wide Operation Range: 4V to 80V
- Reverse Input Protection to –60V
- Low 7µA Shutdown Current (LT4356-1)
- Auxiliary Amplifier for Level Detection Comparator or Linear Regulator Controller (LT4356-2)
- Adjustable Fault Timer
- Controls N-channel MOSFET
- Shutdown Pin Withstands –60V to 100V
- Fault Output Indication
- Guaranteed Operation to 125°C
- Available in (4mm × 3mm) 12-Pin DFN, 10-Pin MSOP or 16-Pin SO Packages
The LT4356 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 also monitors the voltage drop between the VCC and SNS pins to protect against overcurrent faults. An internal amplifier 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. After a cool down period, the GATE 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 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 7µA for the LT4356-1 during shutdown. The LT4356-2 differs from the LT4356-1 during shutdown by reducing the quiescent current to 60µA and keeping alive the auxiliary amplifier for uses such as an undervoltage lockout or always-on regulator.
|Low Current Shutdown||7uA||60uA||7uA|
|Aux Amp In Shutdown||OFF||Always Alive||OFF|
|Fault Retry||Retry||Retry||Latch Off|
|Packages||DFN-12, MS-10, SO-16||DFN-12, SO-16||DFN-12, MS-10, SO-16|
|Temp Grades||C, I, H, MP||C, I, H, MP||C, I, H, MP|
- Automotive/Avionic Surge Protection
- Hot Swap/Live Insertion
- High Side Switch for Battery Powered Systems
- Intrinsic Safety Applications
Product Lifecycle Recommended for New Designs
This product has been released to the market. The data sheet contains all final specifications and operating conditions. For new designs, ADI recommends utilization of these products.
Evaluation Kits (2)
Demonstration Circuit DC1018B-B showcases the LT4356-2 Surge Stopper in a 12V, 3A application. Input transients of up to 60V are limited to 16V at the output; sustained overvoltage conditions cause the limiter to trip off and retry after the overvoltage is removed.
LEDs indicate the presence of +12V input and output, as well as state of the fault output, FLT# and enable output, EN.
Input and output connections are made by 93 mil turrets which if removed, accommodate insertion of up to 12 gauge wires for in-situ testing.
Design files for this circuit board are available below.
- Servers, Routers, Switches
- Mass Storage
- Fan Trays
- Automotive Modules
Features & Benefits
- For Automotive Applications up to 3A
- Triple Layout for D-Pak, D2-Pak or S-8 MOSFETs
- 0.093-inch Turret Holes Accommodate 12 AWG Wire
- LEDs Show Input, Outputs, Fault and Enable
- Easily Modified for up to 20A
Tools & Simulations
LTspice® is a powerful, fast and free simulation software, schematic capture and waveform viewer with enhancements and models for improving the simulation of analog circuits.
To launch ready-to-run LTspice demonstration circuits for this part:
Step 1: Download and install LTspice on your computer.
Step 2: Click on the link in the section below to download a demonstration circuit.
Step 3: If LTspice does not automatically open after clicking the link below, you can instead run the simulation by right clicking on the link and selecting “Save Target As.” After saving the file to your computer, start LTspice and open the demonstration circuit by selecting ‘Open’ from the ‘File’ menu.
Models for the following parts are available in LTspice:
LT4356-1 Companion Parts
Recommended Related Parts
LT Journal (5)
ADI has always placed the highest emphasis on delivering products that meet the maximum levels of quality and reliability. We achieve this by incorporating quality and reliability checks in every scope of product and process design, and in the manufacturing process as well. "Zero defects" for shipped products is always our goal.
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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 Analog Devices, Inc. sales office or authorized distributor. Pricing displayed for Evaluation Boards and Kits is based on 1-piece pricing.