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  2. Power Management
  3. Switching Regulators
  4. Step-Down (Buck) Regulators
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  6. LT3503

Data Sheet
PDF
JP
User Guide
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Overview

Features and Benefits

  • Wide Input Range: 3.6V to 20V
  • 5V at 1.2A from 11V to 18V Input
  • 5V at 1A from 7.2V to 18V Input
  • 3.3V at 1.2A from 8.5V to 12V Input
  • 3.3V at 1A from 5.5V to 12V Input
  • Fixed Frequency Operation: 2.2MHz
  • Output Adjustable Down to 780mV
  • Short-Circuit Robust
  • Uses Tiny Capacitors and Inductors
  • Soft-Start
  • Internally Compensated
  • Low Shutdown Current: <2µA
  • Low VCESAT Switch: 400mV at 1A
  • Thermally Enhanced, 2mm × 3mm 6-Pin DFN Low Profile Package

Product Details

The LT3503 is a current mode PWM step-down DC/DC converter with an internal 1.45A power switch. The wide operating input range of 3.6V to 20V makes the LT3503 ideal for regulating power from a wide variety of sources. Its high operating frequency allows the use of tiny, low cost inductors and ceramic capacitors, resulting in low, predictable output ripple.

Cycle-by-cycle current limit provides protection against shorted outputs and soft-start eliminates input current surge during start-up. The low current (<2µA) shutdown mode provides output disconnect, enabling easy power management in battery-powered systems.

Applications

  • Automotive Battery Regulation
  • Industrial Control Supplies
  • Wall Transformer Regulation
  • Distributed Supply Regulation
  • Battery-Powered Equipment

Product Categories

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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 (1)

Documentation & Resources

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  • Data Sheet (1)
  • Reliability Data (1)
  • User Guide (1)
    • Document Type

    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

    LTspice Simulations

    LT3503 Demo Circuit - 1.2A, 2.25MHz Step-down Regulator (12V to 3.3V @ 1.2A)

    Models for the following parts are available in LTspice:

    LT3503

    Product Recommendations

    LT3503 Companion Parts

    Recommended Related Parts

    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
    LT3503EDCB#TRMPBF Material Declaration Reliability Data 6-Lead DFN (2mm x 3mm w/ EP)
    LT3503EDCB#TRPBF Material Declaration Reliability Data 6-Lead DFN (2mm x 3mm w/ EP)
    Wafer Fabrication Data R530 Reliability Data

    Support & Discussions

    LT3503 Contact ADI Technical Support »
    LT3503 Ask your question »
    LT3503 Contact ADI Technical Support » LT3503 Ask your question »

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