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LT4256-1: Positive High Voltage Hot Swap Controllers Data Sheet8/27/2007PDF213K
Overview
Features and Benefits
- Allows Safe Board Insertion and Removal from a Live Backplane
- Controls Supply Voltage from 10.8V to 80V
- Foldback Current Limiting
- Overcurrent Fault Detection
- Drives an External N-Channel MOSFET
- Programmable Supply Voltage Power-Up Rate
- Undervoltage Protection
- Latch Off Operation Mode (LT4256-1)
- Automatic Retry (LT4256-2)
- Available in an 8-Pin SO Package
Product Details
The LT4256-1/LT4256-2 are high voltage Hot Swap™ controllers that allow a board to be safely inserted and removed from a live backplane. An internal driver drives an external N-channel MOSFET switch to control supply voltages ranging from 10.8V to 80V.
The LT4256-1/LT4256-2 features an adjustable analog foldback current limit. If the supply remains in current limit for more than a programmable time, the N-channel MOSFET shuts off and the PWRGD output asserts low. The LT4256-2 automatically restarts after a time-out delay. The LT4256-1 latches off until the UV pin is cycled low.
The PWRGD output indicates when the output voltage rises above a programmed level. An external resistor string from VCC provides programmable undervoltage protection.
The LT4256 can be used as an upgrade to LT1641 designs.
The LT4256-1 and LT4256-2 are available in an 8-pin SO package that is pin compatible with the LT1641.
Retry / Latch Off | Features | Package | |
LT4256-1 | Latch Off | UV | SO-8 |
LT4256-2 | Retry | UV | SO-8 |
LT4256-3 | Latch Off or Retry | UV/OV, Open Circuit Detect | SSOP-16 |
Applications
- Hot Board Insertion
- Electronic Circuit Breaker/Power Bussing
- Industrial High Side Switch/Circuit Breaker
- 24V/48V Industrial/Alarm Systems
- Ideally Suited for 12V, 24V and 48V Distributed Power Systems
- 48V Telecom Systems
Product Categories
Markets and Technologies
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 (3)
Documentation & Resources
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R568 Reliability Data3/23/2018PDF179 K
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DC1354A - Demo Manual9/24/2009PDF1M
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Hot Swap Controllers7/13/2017PDF778 K
Tools & Simulations
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Design Resources
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.View our quality and reliability program and certifications for more information.
Part Number | Material Declaration | Reliability Data | Pin/Package Drawing | CAD Symbols, Footprints & 3D Models |
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LT4256-1CS8#PBF | Material Declaration | Reliability Data | 8-Lead SOIC (Narrow 0.15 Inch) | |
LT4256-1CS8#TRPBF | Material Declaration | Reliability Data | 8-Lead SOIC (Narrow 0.15 Inch) | |
LT4256-1IS8#PBF | Material Declaration | Reliability Data | 8-Lead SOIC (Narrow 0.15 Inch) | |
LT4256-1IS8#TRPBF | Material Declaration | Reliability Data | 8-Lead SOIC (Narrow 0.15 Inch) | |
LT4256-2CS8#PBF | Material Declaration | Reliability Data | 8-Lead SOIC (Narrow 0.15 Inch) | |
LT4256-2CS8#TRPBF | Material Declaration | Reliability Data | 8-Lead SOIC (Narrow 0.15 Inch) | |
LT4256-2IS8#PBF | Material Declaration | Reliability Data | 8-Lead SOIC (Narrow 0.15 Inch) | |
LT4256-2IS8#TRPBF | Material Declaration | Reliability Data | 8-Lead SOIC (Narrow 0.15 Inch) | |
Wafer Fabrication Data | R568 Reliability Data |
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Pricing displayed is based on 1-piece. The USA list pricing shown is for budgetary use only, shown in United States dollars (FOB USA per unit), and is subject to change. International prices may vary due to local duties, taxes, fees and exchange rates.