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  6. LTC3865

Data Sheet
PDF
JP
User Guide
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Overview

Features and Benefits

  • Dual, 180° Phased Controllers
  • 2-Pin VID Output Voltage Programming from 0.6V to 5V
  • High Efficiency: Up to 95%
  • RSENSE or DCR Current Sensing
  • Phase-Lockable Fixed Frequency 250kHz to 770kHz
  • Adjustable Current Limit
  • Dual N-Channel MOSFET Synchronous Drive
  • Wide VIN Range: 4.5V to 38V Operation
  • Adjustable Soft-Start Current Ramping or Tracking
  • Output OV Protection With Reverse Current Limit
  • Power Good Output Voltage Monitor
  • 32-Pin 5mm × 5mm QFN and 38-Lead TSSOP Packages

Product Details

The LTC3865/LTC3865-1 are high performance dual synchronous step-down DC/DC switching regulator controllers that drive all N-channel synchronous power MOSFET stages. A constant frequency current mode architecture allows a phase-lockable frequency of up to 770kHz. Power loss and noise are minimized by operating the two controller output stages out of phase.

OPTI-LOOP® compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. Independent track/soft-start pins for each controller ramp the output voltage during start-up. Current foldback limits MOSFET heat dissipation during short-circuit conditions. The MODE/PLLIN pin selects among Burst Mode® operation, pulse-skipping mode, and continuous inductor current mode. The output voltages can be precisely programmed by pin strapping or external resistors.

The LTC3865/LTC3865-1 are available in low profile (5mm × 5mm) 32-pin QFN and 38-Lead thermally enhanced TSSOP packages.

Applications

  • DC Power Distribution Systems

Product Categories

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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)

Documentation & Resources

  • View All (5)
  • Data Sheet (1)
  • Reliability Data (1)
  • User Guide (2)
  • Technical Article (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

    LTC3865 Demo Circuit - High Efficiency 1.5V @ 15A, 1.2V @ 15A Step-Down Converter Using Sense Resistors

    Models for the following parts are available in LTspice:

    LTC3865
    LTC3865-1

    Product Recommendations

    LTC3865 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
    LTC3865EFE#PBF Material Declaration Reliability Data 38-Lead TSSOP w/ EP
    LTC3865EFE#TRPBF Material Declaration Reliability Data 38-Lead TSSOP w/ EP
    LTC3865EUH#PBF Material Declaration Reliability Data 32-Lead QFN (5mm x 5mm x 0.75mm w/ EP)
    LTC3865EUH#TRPBF Material Declaration Reliability Data 32-Lead QFN (5mm x 5mm x 0.75mm w/ EP)
    LTC3865EUH-1#PBF Material Declaration Reliability Data 32-Lead QFN (5mm x 5mm x 0.75mm w/ EP)
    LTC3865EUH-1#TRPBF Material Declaration Reliability Data 32-Lead QFN (5mm x 5mm x 0.75mm w/ EP)
    LTC3865IFE#PBF Material Declaration Reliability Data 38-Lead TSSOP w/ EP
    LTC3865IFE#TRPBF Material Declaration Reliability Data 38-Lead TSSOP w/ EP
    LTC3865IUH#PBF Material Declaration Reliability Data 32-Lead QFN (5mm x 5mm x 0.75mm w/ EP)
    LTC3865IUH#TRPBF Material Declaration Reliability Data 32-Lead QFN (5mm x 5mm x 0.75mm w/ EP)
    LTC3865IUH-1#PBF Material Declaration Reliability Data 32-Lead QFN (5mm x 5mm x 0.75mm w/ EP)
    LTC3865IUH-1#TRPBF Material Declaration Reliability Data 32-Lead QFN (5mm x 5mm x 0.75mm w/ EP)
    Wafer Fabrication Data R526 Reliability Data

    PCN-PDN Information

    Select a model from the dropdown below to subscribe to PCN/PDN notifications and view past notifications as well.

    Select Model for PCN Information
    • LTC3865EFE#PBF Production
    • LTC3865EFE#TRPBF Production
    • LTC3865EUH#PBF Production
    • LTC3865EUH#TRPBF Production
    • LTC3865EUH-1#PBF Production
    • LTC3865EUH-1#TRPBF Production
    • LTC3865IFE#PBF Production
    • LTC3865IFE#TRPBF Production
    • LTC3865IUH#PBF Production
    • LTC3865IUH#TRPBF Production
    • LTC3865IUH-1#PBF Production
    • LTC3865IUH-1#TRPBF Production

    Support & Discussions

    LTC3865 Contact ADI Technical Support »
    LTC3865 Ask your question »
    LTC3865 Contact ADI Technical Support » LTC3865 Ask your question »

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