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  6. LT1109

Data Sheet
PDF
User Guide
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Overview

Features and Benefits

  • Uses Off-the-Shelf Inductors
  • Only 33µH Inductor Required
  • Low Cost
  • 3-Lead TO-92, SO8, or 8-Pin DIP
  • Adjustable or Fixed 5V or 12V Output
  • 120kHz Oscillator
  • Only Three External Components Required
  • 320µA IQ
  • 1.6V Minimum Start-Up Voltage
  • Logic Controlled Shutdown

Product Details

The LT1109 is a simple step-up DC/DC converter. Available in 8-pin SO, 3-lead TO-92 (fixed output only) or miniDIP packages, the devices require only three external components to construct a complete DC/DC converter. Current drain is just 320µA at no load, making the device ideal for cost-sensitive applications where standby current must be kept to a minimum.

The LT1109-5 can deliver 5V at 100mA from a 3V input and the LT1109-12 can deliver 12V at 60mA from a 5V input. The 8-pin versions also feature a logic controlled SHUTDOWN pin that turns off the oscillator when taken low. The gated-oscillator design requires no frequency compensation components. The high frequency 120kHz oscillator permits the use of small surface mount inductors and capacitors. For a 5V to 12V at 120mA converter, see the LT1109A. For a 5V to 12V at 200mA converter with 20µA shutdown current, see the LT1301.

Applications

  • Flash Memory VPP Generators
  • 3V to 5V Converters
  • 5V to 12V Converters
  • Disk Drives
  • PC Plug-In Cards
  • Peripherals
  • 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

  • View All (6)
  • Data Sheet (1)
  • Reliability Data (1)
  • Application Note (1)
  • User Guide (1)
  • Design Note (2)
    • 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.

    LTspice

    Models for the following parts are available in LTspice:

    LT1109
    LT1109-12
    LT1109-5
    LT1109A
    LT1109A-12
    LT1109A-5

    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
    LT1109CN8#PBF Material Declaration Reliability Data 8-Lead PDIP (Narrow 0.3 Inch)
    LT1109CN8-12#PBF Material Declaration Reliability Data 8-Lead PDIP (Narrow 0.3 Inch)
    LT1109CN8-5#PBF Material Declaration Reliability Data 8-Lead PDIP (Narrow 0.3 Inch)
    LT1109CS8#PBF Material Declaration Reliability Data 8-Lead SOIC (Narrow 0.15 Inch)
    LT1109CS8#TRPBF Material Declaration Reliability Data 8-Lead SOIC (Narrow 0.15 Inch)
    LT1109CS8-12#PBF Material Declaration Reliability Data 8-Lead SOIC (Narrow 0.15 Inch)
    LT1109CS8-12#TRPBF Material Declaration Reliability Data 8-Lead SOIC (Narrow 0.15 Inch)
    LT1109CS8-5#PBF Material Declaration Reliability Data 8-Lead SOIC (Narrow 0.15 Inch)
    LT1109CS8-5#TRPBF Material Declaration Reliability Data 8-Lead SOIC (Narrow 0.15 Inch)
    LT1109CZ-12#PBF Material Declaration Reliability Data 3-Lead TO-92
    LT1109CZ-5#PBF Material Declaration Reliability Data 3-Lead TO-92
    Wafer Fabrication Data R177 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
    • LT1109CN8#PBF Production
    • LT1109CN8-12#PBF Production
    • LT1109CN8-5#PBF Production
    • LT1109CS8#PBF Production
    • LT1109CS8#TRPBF Production
    • LT1109CS8-12#PBF Production
    • LT1109CS8-12#TRPBF Production
    • LT1109CS8-5#PBF Production
    • LT1109CS8-5#TRPBF Production
    • LT1109CZ-12#PBF Production
    • LT1109CZ-5#PBF Production

    Support & Discussions

    LT1109 Contact ADI Technical Support »
    LT1109 Ask your question »
    LT1109 Contact ADI Technical Support » LT1109 Ask your question »

    Sample & Buy


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