National Semiconductor | High-performance Analog

 

 LM2694   

30V, 600 mA Step Down Switching Regulator
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Features
  • Integrated N-Channel buck switch
  • Integrated start-up regulator
  • Input Voltage Range: 8V to 30V
  • No loop compensation required
  • Ultra-Fast transient response
  • Operating frequency remains constant with load current and input voltage variations
  • Maximum Duty Cycle Limited During Start-Up
  • Adjustable output voltage
  • Valley Current Limit At 0.6A
  • Maximum switching frequency: 1 MHz
  • Precision internal reference
  • Low bias current
  • Highly efficient operation
  • Thermal shutdown
  • Description

    The LM2694 Step Down Switching Regulator features all of the functions needed to implement a low cost, efficient, buck bias regulator capable of supplying 0.6A to the load. This buck regulator contains an N-Channel Buck Switch, and is available in the 3 x 3 thermally enhanced LLP-10 package and a TSSOP-14 package. The feedback regulation scheme requires no loop compensation, results in fast load transient response, and simplifies circuit implementation. The operating frequency remains constant with line and load variations due to the inverse relationship between the input voltage and the on-time. The valley current limit results in a smooth transition from constant voltage to constant current mode when current limit is detected, reducing the frequency and output voltage, without the use of foldback. Additional features include: VCC under-voltage lockout, thermal shutdown, gate drive under-voltage lockout, and maximum duty cycle limiter.


    Applications

  • High Efficiency Point-Of-Load (POL) Regulator
  • Non-Isolated Telecommunication Buck Regulator
  • Secondary High Voltage Post Regulator



  • Typical Application
    *click for larger image


    Block Diagram
    *click for larger image



    Typical Performance
    *click for larger image


     

    ParametersValues
    Output Current 600 mA
    Input Min Voltage 8 Volt
    Input Max Voltage 30 Volt
    Output Min 2.5 Volt
    Output Max 24 Volt
    Frequency Min 50 kHz
    Frequency Max 1000 kHz
    Efficiency (peak) 93 %
    On/Off Pin Yes
    PowerGood / Error Flag No
    SoftStart Yes
    Sync Pin No
    Inverting Yes
    Flyback No
    RegType Switching Regulator
    Temperature Min -40 deg C
    Temperature Max 125 deg C
    Adjustable Output Yes
    Adj Switch Frequency Yes
    PWM Mode Constant on-time
    Topology Buck
    Special Features No compensation required, ultra-fast transient response
    Step-Down Yes
    Multiple Output Capability No
    Output Power Undefined Watt
    Output Voltage Undefined Volt
    Output Range 2.5V to 24V
    Switching Frequency 1000 kHz
    Regulator Family Undefined
    Synchronous Rectification No

    Datasheets
    TitleSizeDateOther
    Language
    LM2694 30V, 600 mA Step Down Switching Regulator764
    Kbytes
    12-May-06日本語  


    Application Notes
    TitleSizeDateOther
    Language
    AN-1472: Application Note 1472 LM2694 Evaluation Board796
    Kbytes
    16-May-06 

    Part Number(s)
    (NSID)
    Top ViewAvailabilityCurrent Reported StockBudgetary PricingPack
    Size
    LM2694MT/NOPB

    LM2694MT

    RoHS Status


    TSSOP
    Full production
    Lead Time: 6 weeks

    Samples
    DistributorRegionQty
    ARROWWorldwide246
    DIGI-KEYWorldwide1851
    FARNELLEurope and Asia299
    NEWARKAmericas114
    RS COMPONENTSWorldwide25
    TAYLORAmericas246
    $1.00 each at 1K+ pcsrail
    of
    94
    LM2694MTX/NOPB

    LM2694MTX

    RoHS Status


    TSSOP
    Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    DIGI-KEYWorldwide0
    $1.00 each at 1K+ pcsreel
    of
    2500
    LM2694SD/NOPB

    LM2694SD

    RoHS Status


    LLP
    Full production
    Lead Time: 6 weeks

    Samples
    DistributorRegionQty
    DIGI-KEYWorldwide0
    $1.00 each at 1K+ pcsreel
    of
    1000
    LM2694SDX/NOPB

    LM2694SDX

    RoHS Status


    LLP
    Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    DIGI-KEYWorldwide0
    $1.00 each at 1K+ pcsreel
    of
    4500

    All information pertaining to the RoHS Compliance Standard can be found at http://www.national.com/en/packaging/leadfree.html.

    Moisture Sensitivity Level Data for LM2694.

    A RoHS compliance or an IPC 1752 report can be acquired at http://www.national.com/en/packaging/greennopb.html.

    National's certificate of product compliance for LM2694 is located at RoHS Status.

    Part Number(s)
    (NSID)
    DescriptionAvailabilityCurrent Reported StockBudgetary PricingPack
    Size
    LM2694EVAL
    30V, 600 mA Step Down Switching RegulatorFull production


     
    DistributorRegionQty
    DIGI-KEYWorldwide0
    $34.50 each1

    Description:

    LM2694 30V, 600 mA Step Down Switching Regulator

    Features:

    • No loop compensation required
    • Ultra-Fast transient response
    • Operating frequency remains constant with load current and input voltage variations
    • Maximum Duty Cycle Limited during Start-up
    • Adjustable output voltage
    • Valley Current Limit At 0.6A
    • Maximum switching frequency: 1 MHz
    • Precision internal reference
    • Low bias current
    • Highly efficient operation
    • Thermal shutdown

    Applications:

    • High Efficiency Point-Of-Load (POL) Regulator
    • Non-Isolated Telecommunication Buck Regulator
    • Secondary High Voltage Post Regulator



    National Semiconductor follows the provisions of the Product Stewardship Guide for Customers (CSP-9-111C1) and Banned Substances and Materials of Interest Specification (CSP-9-111S2) for regulatory environmental compliance. Details may be found at: www.national.com/en/packaging/greennopb.html. Lead free products are RoHS compliant.

    Lead Free product status is available through the search tool located here

    Part Number(s)
    (NSID)
    Weight
    (milligrams)
    TypePinsMSL RatingPeak ReflowRoHS
    Status
    CAD SymbolsModelsPackage
    Marking
    Format
    LM2694MT/NOPB

    LM2694MT
    53.783
    54.004
    TSSOP141
    1
    260
    260
    DetailDownloadN/A
    NSUZXYTT
    L2694
    MT
    LM2694MTX/NOPB

    LM2694MTX
    53.783
    54.004
    TSSOP141
    1
    260
    260
    DetailDownloadN/A
    NSUZXYTT
    L2694
    MT
    LM2694SD/NOPB

    LM2694SD
    21.112
    21.182
    LLP101
    1
    260
    260
    DetailDownloadN/A
    ZXYTT
    L2694
    LM2694SDX/NOPB

    LM2694SDX
    21.112
    21.182
    LLP101
    1
    260
    260
    DetailDownloadN/A
    ZXYTT
    L2694

    All information pertaining to the RoHS Compliance Standard can be found at http://www.national.com/en/packaging/leadfree.html.

    Moisture Sensitivity Level Data for LM2694.

    A RoHS compliance or an IPC 1752 report can be acquired at http://www.national.com/en/packaging/greennopb.html.

    National's certificate of product compliance for LM2694 is located at RoHS Status.

    CAD Symbols and Models
    Download LM2694 CAD Symbols
     Models
    N/A


    Reliability Metrics
    Part Number Process EFR Reject EFR Sample Size PPM LTA Rejects LTA Device Hours FITS MTTF (Hours)
    LM2694MTABCD15004268000639400011814314958
    LM2694MTXABCD15004268000639400011814314958
    LM2694SDABCD15004268000639400011814314958
    LM2694SDXABCD15004268000639400011814314958

    Note: The Early Failure Rates (EFR) were calculated as point estimate PPM based on rejects and sample size for EFR. The Long Term Failure Rates were calculated at 60% confidence using the Arrhenius equation at 0.7eV activation energy and derating the assumed stress temperature of 150°C to an application temperature of 55°C.

    For more information on Reliability Metrics, please click here.


    All information pertaining to the RoHS Compliance Standard can be found at http://www.national.com/en/packaging/leadfree.html.

    Moisture Sensitivity Level Data for LM2694.

    A RoHS compliance or an IPC 1752 report can be acquired at http://www.national.com/en/packaging/greennopb.html.

    National's certificate of product compliance for LM2694 is located at RoHS Status.

    [Information as of 8-Feb-2012]