Overview

Features and Benefits

  • Allows Safe Board Insertion and Removal from a Live –48V Backplane
  • Floating Topology Permits Very High Voltage Operation
  • Current Limit With Circuit Breaker Timer
  • Fast Response Time Limits Peak Fault Current
  • Programmable Soft-Start Current Limit
  • Programmable Timer with Drain Voltage Accelerated Response
  • ±1% Undervoltage/Overvoltage Threshold (LTC4252C)
  • Improved Ruggedness Shunt Regulator
  • Adjustable Undervoltage/Overvoltage Protection
  • LTC4252B-1/LTC4252C-1: Latch Off After Fault
  • LTC4252B-2/LTC4252C-2: Automatic Retry After Fault
  • Available in 8-Pin and 10-Pin MSOP Packages

Product Details

The LTC4252 negative voltage Hot Swap controller allows a board to be safely inserted and removed from a live backplane. Output current is controlled by three stages of current limiting: a timed circuit breaker, active current limiting and a fast feedforward path that limits peak current under worst-case catastrophic fault conditions.

Adjustable undervoltage and overvoltage detectors disconnect the load whenever the input supply exceeds the desired operating range. The LTC4252’s supply input is shunt regulated, allowing safe operation with very high supply voltages. A multifunction timer delays initial startup and controls the circuit breaker’s response time. The circuit breaker’s response time is accelerated by sensing excessive MOSFET drain voltage, keeping the MOSFET within its safe operating area (SOA). An adjustable softstart circuit controls MOSFET inrush current at start-up.

The LTC4252-2 provides automatic retry after a fault. The LTC4252C-1/LTC4252C-2 feature tight ±1% undervoltage/ overvoltage threshold accuracy. The LTC4252 is available in either an 8-pin or 10-pin MSOP.

The LTC4252B and LTC4252C improve the ruggedness of the shunt regulator in the LTC4252 and LTC4252A.

UV/OV % Latch Off/Retry Package
LTC4252-1 4.6% Latch off MS-8, MS-10
LTC4252-2 4.8% Retry MS-8, MS-10
LTC4252A-1 1% Latch off MS-10
LTC4252A-2 1% Retry MS-10
LTC4252B-1 4.6% Latch off MS-8, MS-10
LTC4252B-2 4.6% Retry MS-8, MS-10
LTC4252C-1 1% Latch off MS-10
LTC4252C-2 1% Retry MS-10

Applications

  • Hot Board Insertion
  • Electronic Circuit Breaker
  • –48V Distributed Power Systems
  • Negative Power Supply Control
  • Central Office Switching
  • High Availability Servers
  • ATCA

Product Lifecycle icon-recommended Production

At least one model within this product family is in production and available for purchase. The product is appropriate for new designs but newer alternatives may exist.

Evaluation Kits (2)

Tools & Simulations

LTspice

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.

LTspice

Models for the following parts are available in LTspice:

LTC4252C-1
LTC4252C-2

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.

Discussions

LTC4252B-1 Didn't find what you were looking for? Ask the Analog community »

Sample & Buy

Sample & Buy functionality exists in desktop site
Back
Check Inventory


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.


Price Table Help

 

Evaluation Boards Pricing displayed is based on 1-piece.
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.