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  5. LT8643S-2

Data Sheet Rev. B
PDF
JP

Overview

Features and Benefits

  • Silent Switcher® Architecture
    • Ultralow EMI Emissions
    • Optional Spread Spectrum Modulation
  • High Efficiency at High Frequency
    • Up to 96% Efficiency at 1MHz, 12VIN to 5VOUT
    • Up to 95% Efficiency at 2MHz, 12VIN to 5VOUT
  • Wide Input Voltage Range: 3.4V to 42V
  • 6A Maximum Continuous, 7A Peak Output
  • External Compensation: Fast Transient Response and Current Sharing (LT8643S-2)
  • Fast Minimum Switch On-Time: 30ns
  • Ultralow Quiescent Current Burst Mode® Operation
    • 2.5μA IQ Regulating 12VIN to 3.3VOUT (LT8640S-2)
    • Output Ripple < 10mVP-P
  • Low Dropout Under All Conditions: 100mV at 1A
  • Forced Continuous Mode
  • Adjustable and Synchronizable: 200kHz to 3MHz
  • Output Soft-Start and Tracking
  • Small 24-Lead 4mm × 4mm LQFN Package
  • AEC-Q100 Qualified for Automotive Applications

Product Details

The LT8640S-2/LT8643S-2 synchronous step-down regulator features Silent Switcher architecture designed to minimize EMI emissions while delivering high efficiency at high switching frequencies. Peak current mode control with a 30ns minimum on-time allows high step-down ratios even at high switching frequencies. The LT8643S-2 has external compensation to enable current sharing and fast transient response at high switching frequencies.

Burst Mode operation enables ultralow standby current consumption, forced continuous mode can control frequency harmonics across the entire output load range, or spread spectrum operation can further reduce EMI emissions.

APPLICATIONS

  • Automotive and Industrial Supplies
  • General Purpose Step-Down

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Documentation & Resources

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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
    LT8643SEV-2#PBF Material Declaration Reliability Data 24-Lead LQFN (4mm x 4mm x 0.94mm w/ EP)
    LT8643SEV-2#TRPBF Material Declaration Reliability Data 24-Lead LQFN (4mm x 4mm x 0.94mm w/ EP)
    LT8643SHV-2#PBF Material Declaration Reliability Data 24-Lead LQFN (4mm x 4mm x 0.94mm w/ EP)
    LT8643SHV-2#TRPBF Material Declaration Reliability Data 24-Lead LQFN (4mm x 4mm x 0.94mm w/ EP)
    LT8643SHV-2#WPBF Material Declaration Reliability Data 24-Lead LQFN (4mm x 4mm x 0.94mm w/ EP)
    LT8643SHV-2#WTRPBF Material Declaration Reliability Data 24-Lead LQFN (4mm x 4mm x 0.94mm w/ EP)
    LT8643SIV-2#PBF Material Declaration Reliability Data 24-Lead LQFN (4mm x 4mm x 0.94mm w/ EP)
    LT8643SIV-2#TRPBF Material Declaration Reliability Data 24-Lead LQFN (4mm x 4mm x 0.94mm w/ EP)
    LT8643SIV-2#WPBF Material Declaration Reliability Data 24-Lead LQFN (4mm x 4mm x 0.94mm w/ EP)
    LT8643SIV-2#WTRPBF Material Declaration Reliability Data 24-Lead LQFN (4mm x 4mm x 0.94mm w/ EP)
    Wafer Fabrication Data

    PCN-PDN Information

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    Select Model for PCN Information
    • LT8643SEV-2#PBF Production
    • LT8643SEV-2#TRPBF Production
    • LT8643SHV-2#PBF Production
    • LT8643SHV-2#TRPBF Production
    • LT8643SHV-2#WPBF Production
    • LT8643SHV-2#WTRPBF Production
    • LT8643SIV-2#PBF Production
    • LT8643SIV-2#TRPBF Production
    • LT8643SIV-2#WPBF Production
    • LT8643SIV-2#WTRPBF Production

    Support & Discussions

    LT8643S-2 Discussions

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