National Semiconductor | High-performance Analog

 

 LM2734   

Thin SOT23 1A Load Step-Down DC-DC Regulator
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Features

  • Thin SOT23-6 package
  • 3.0V to 20V input voltage range
  • 0.8V to 18V output voltage range
  • 1A output current
  • 550kHz (LM2734Y) and 1.6MHz (LM2734X)

  • switching frequencies
  • 300mΩ NMOS switch
  • 30nA shutdown current
  • 0.8V, 2% internal voltage reference
  • Internal soft-start
  • Current-Mode, PWM operation
  • WEBENCH® online design tool
  • Thermal shutdown
  • LM2734XQ/LM2734YQ are AEC-Q100 Grade 1 qualified and are manufactured on an Automotive Grade Flow
  • Description

    The LM2734 regulator is a monolithic, high frequency, PWM step-down DC/DC converter in a 6-pin Thin SOT23 package. It provides all the active functions to provide local DC/DC conversion with fast transient response and accurate regulation in the smallest possible PCB area.

    With a minimum of external components and online design support through WEBENCH® , the LM2734 is easy to use. The ability to drive 1A loads with an internal 300mΩ NMOS switch using state-of-the-art 0.5µm BiCMOS technology results in the best power density available. The world class control circuitry allows for on-times as low as 13ns, thus supporting exceptionally high frequency conversion over the entire 3V to 20V input operating range down to the minimum output voltage of 0.8V. Switching frequency is internally set to 550kHz (LM2734Y) or 1.6MHz (LM2734X), allowing the use of extremely small surface mount inductors and chip capacitors. Even though the operating frequencies are very high, efficiencies up to 90% are easy to achieve. External shutdown is included, featuring an ultra-low stand-by current of 30nA. The LM2734 utilizes current-mode control and internal compensation to provide high-performance regulation over a wide range of operating conditions. Additional features include internal soft-start circuitry to reduce inrush current, pulse-by-pulse current limit, thermal shutdown, and output over-voltage protection.


    Applications

  • Local Point of Load Regulation
  • Core Power in HDDs
  • Set-Top Boxes
  • Battery Powered Devices
  • USB Powered Devices
  • DSL Modems
  • Notebook Computers
  • Automotive
  • WEBENCH® LM2734X
        Min   Max   Range  
      Vin V    3.00 – 20.00V  
      Vout V    0.80 – 18.00V  
      Iout A    ≤ 1.00A  
      Ambient Temp °C    ≤ 100°C  
    Footprint BOM Cost Efficiency
     
     
     
     
    What are WEBENCH® tools?

    Also Recommended
    LM26511.5A Synchronous Buck Regulator
    LM273411.5A, 2MHz Fsw, Frequency Sync
    LM2734Z3MHz Version
    LM27381.5A Version
    LM50101A 80V Switching Reg



    Typical Application
    click for larger image


    Block Diagram
    click for larger image



    Typical Performance
    click for larger image


    Parameters / ValuesLM2734 LM2651 LM27341 LM2734Z LM2738 LM5010
    Output Current1000 mA 1500 mA 1500 mA 1000 mA 1500 mA 1000 mA
    Input Min Voltage3 Volt 4 Volt 3 Volt 3 Volt 3 Volt 8 Volt
    Input Max Voltage20 Volt 14 Volt 20 Volt 20 Volt 20 Volt 75 Volt
    Output Min0.8 Volt 3.3, 1.24 Volt 1 Volt 0.8 Volt 0.8 Volt 2.5 Volt
    Output Max18 Volt 3.3, 13 Volt 18 Volt 18 Volt 18 Volt 70 Volt
    Frequency Min1600, 550 kHz 300 kHz 1000 kHz 3000 kHz 364, 1280 kHz 50 kHz
    Frequency Max1600, 550 kHz 300 kHz 2350 kHz 3000 kHz 1920, 676 kHz 1000 kHz
    Efficiency (peak)90, 94 % 97 % 93 % 88 % 94.5, 92 % 91 %
    On/Off PinYes Yes Yes Yes Yes Yes
    PowerGood / Error FlagNo No No No No No
    SoftStartYes Yes Yes Yes Yes Yes
    Sync PinNo No Yes No No No
    InvertingNo No No No No Yes
    FlybackNo No No No No No
    RegTypeSwitching Regulator Switching Regulator Switching Regulator Switching Regulator Switching Regulator Switching Regulator
    Temperature Min-40 deg C -40 deg C -40 deg C -40 deg C -40 deg C -40 deg C
    Temperature Max125 deg C 125 deg C 125 deg C 125 deg C 125 deg C 125 deg C
    Adjustable OutputYes Yes, No Yes Yes Yes Yes
    Adj Switch FrequencyNo No Yes No No Yes
    PWM ModeCurrent Current Mode Control Current Current Current Constant on-time
    TopologyBuck Synchronous Buck Non-Synchronous Buck Regulator Buck Buck Buck
    Special FeaturesOVP, internal compensation, 30nA shutdown current, pulse-by-pulse current limit Max. Iq at shutdown is 20uA over full temp range, 7uA typical OVP, internal compensation, 70nA shutdown current, pulse-by-pulse current limit OVP, internal compensation, 30nA shutdown current, pulse-by-pulse current limit No compensation required, ultra-fast transient response
    Step-DownYes Yes Yes Yes Yes Yes
    Multiple Output CapabilityNo No No No No No
    Output VoltageUndefined Volt 3.3 Volt Undefined Volt Undefined Volt
    Output Range0.8V to 18V 1.24V to 13V 1.0 - 18V 0.8V to 18V 2.5V to 70V
    Switching Frequency1600, 550 kHz 300 kHz 2000 kHz 3000 kHz 1600, 550 kHz 1000 kHz
    Feedback VoltageUndefined Volt Undefined Volt 1 Volt Undefined Volt 0.8 Volt 2.5 Volt
    Regulator FamilyUndefined Undefined Undefined SIMPLE SWITCHER Undefined
    AEC Q-100 Automotive Grade1 Undefined 1 1
    AutomotiveYes Yes Yes Undefined
    Synchronous RectificationNo Yes No No No No

    Datasheets
    TitleSizeDateOther
    Language
    LM2734 Thin SOT23 1A Load Step-Down DC-DC Regulator487
    Kbytes
    21-Jun-10日本語  


    Application Notes
    TitleSizeDateOther
    Language
    AN-1350: Application Note 1350 LM2734 Evaluation Board639
    Kbytes
    4-Feb-05 
    AN-1822: Application Note 1822 LMH6733 High Definition Video Transmission Over CAT5691
    Kbytes
    14-Jan-09 
    AN-1408: Application Note 1408 Designing Power Over Ethernet Using LM5070 and DP838651553
    Kbytes
    23-Nov-11 中文


    Other Technical Documents
    TitleTypeDate
    Using a strain-gauge transducer in a Wheatstone-bridge configurationExternal Article 2007-10-11
    Power Management Considerations for FPGAs and ASICsPower Designer 2007-03-22
    Advanced Topics in Powering FPGAsPower Designer 2007-03-22
    HD Component Video Over CAT5 Cable Using Current Feedback AmplifiersExternal Article 2009-06-12
    Methods and Features of LED DriversExternal Article 2008-03-01
    Best Layout Practices for Switching Power SuppliesPower Designer 2007-03-21

    Part Number(s)
    (NSID)
    Top ViewAvailabilityCurrent Reported StockBudgetary PricingPack
    Size
    LM2734XMK/NOPB


    RoHS Status


    TSOT
    Full production
    Lead Time: 6 weeks

    Samples
    DistributorRegionQty
    ARROWWorldwide22573
    AVNET-EMWorldwide14000
    CEACAsia Pacific4000
    DIGI-KEYWorldwide3055
    FARNELLEurope and Asia1229
    MOUSERWorldwide776
    NEWARKAmericas741
    TAYLORAmericas23573
    $1.40 each at 1K+ pcsreel
    of
    1000
    LM2734XQMK/NOPB

    Auto Grade 1
    RoHS Status


    TSOT
    Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    DIGI-KEYWorldwide0
    FARNELLEurope and Asia227
    $1.68 each at 1K+ pcsreel
    of
    1000
    LM2734XQMKE/NOPB

    Auto Grade 1
    RoHS Status


    TSOT
    Full production
    Lead Time: 6 weeks

    Samples
    DistributorRegionQty
    DIGI-KEYWorldwide433
    MOUSERWorldwide225
    $1.68 each at 1K+ pcsreel
    of
    250
    LM2734XQMKX/NOPB

    Auto Grade 1
    RoHS Status


    TSOT
    Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    DIGI-KEYWorldwide0
    $1.68 each at 1K+ pcsreel
    of
    3000
    LM2734YMK/NOPB

    LM2734YMK

    RoHS Status


    TSOT
    Full production
    Lead Time: 6 weeks

    Samples
    DistributorRegionQty
    ARROWWorldwide750
    AVNET-EMWorldwide1000
    CEACAsia Pacific14000
    DIGI-KEYWorldwide10490
    FARNELLEurope and Asia1442
    MOUSERWorldwide1255
    NEWARKAmericas1047
    RS COMPONENTSWorldwide350
    TAYLORAmericas3863
    $1.15 each at 1K+ pcsreel
    of
    1000
    LM2734YMKX/NOPB

    LM2734YMKX

    RoHS Status


    TSOT
    Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    AVNET-EMWorldwide3000
    DIGI-KEYWorldwide0
    RSL MICROAsia Pacific18000
    $1.15 each at 1K+ pcsreel
    of
    3000
    LM2734YQMK/NOPB

    Auto Grade 1
    RoHS Status


    TSOT
    Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    DIGI-KEYWorldwide0
    FARNELLEurope and Asia443
    MOUSERWorldwide987
    $1.39 each at 1K+ pcsreel
    of
    1000
    LM2734YQMKE/NOPB

    Auto Grade 1
    RoHS Status


    TSOT
    Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    ARROWWorldwide250
    DIGI-KEYWorldwide437
    MOUSERWorldwide250
    TAYLORAmericas250
    $1.39 each at 1K+ pcsreel
    of
    250
    LM2734YQMKX/NOPB

    Auto Grade 1
    RoHS Status


    TSOT
    Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    DIGI-KEYWorldwide0
    $1.39 each at 1K+ pcsreel
    of
    3000

    Obsolete Versions
    Obsolete PartAlternate Part or SupplierSourceLast Time Buy Date
    LM2734XMFX
    LM2734XMKX
    NATIONAL SEMICONDUCTOR
    01 Dec 2009

    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 LM2734.

    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 LM2734 is located at RoHS Status.

    Part Number(s)
    (NSID)
    DescriptionAvailabilityCurrent Reported StockBudgetary PricingPack
    Size
    LM2734X EVAL
    Thin SOT23 1A Load Step-Down DC-DC RegulatorFull production


     
    DistributorRegionQty
    DIGI-KEYWorldwide0
    $38.00 each1

    Description:

    LM2734 Thin SOT-23 1A Load Step-Down DC-DC Regulator

    Features:

    • Thin SOT-23-6 package
    • 3.0V to 20V input voltage range
    • 0.8V to 18V output voltage range
    • 1A output current
    • 550kHz (LM2734Y) and 1.6MHz (LM2736X) switching frequencies
    • 300m ohm NMOS switch
    • 30nA shutdown current
    • 0.8V, 2% internal voltage reference
    • Internal soft-start
    • Current-Mode, PWM operation
    • WEBENCH online design tool

    Applications:

    • Local Point of Load Regulation
    • Core Power in HDDs
    • Set-Top Boxes
    • Battery Powered Devices
    • USB Powered Devices
    • DSL Modems
    • Notebook Computers

    Contents:

    • A fully assembled LM2734X evaluation board
    • LM2734 datasheet
    • LM2734 eval board appnote

    Part Number(s)
    (NSID)
    DescriptionAvailabilityCurrent Reported StockBudgetary PricingPack
    Size
    LM2734Y EVAL
    Thin SOT23 1A Load Step-Down DC-DC RegulatorFull production


     
    DistributorRegionQty
    DIGI-KEYWorldwide0
    $25.50 each1

    Description:

    LM2734 Thin SOT-23 1A Load Step-Down DC-DC Regulator

    Features:

    • Thin SOT-23-6 package
    • 3.0V to 20V input voltage range
    • 0.8V to 18V output voltage range
    • 1A output current
    • 550kHz (LM2734Y) and 1.6MHz (LM2736X) switching frequencies
    • 300m ohm NMOS switch
    • 30nA shutdown current
    • 0.8V, 2% internal voltage reference
    • Internal soft-start
    • Current-Mode, PWM operation
    • WEBENCH online design tool
    Applications:
    • Local Point of Load Regulation
    • Core Power in HDDs
    • Set-Top Boxes
    • Battery Powered Devices
    • USB Powered Devices
    • DSL Modems
    • Notebook Computers

    Contents:

    • A fully assembled LM2734Y evaluation board
    • LM2734 datasheet
    • LM2734 eval board appnote

    Part Number(s)
    (NSID)
    DescriptionAvailabilityCurrent Reported StockBudgetary PricingPack
    Size
    SP16160CH1RBKIT/NOPB

    High-IF Sub-sampling Receiver Subsystem Reference DesignPreliminary
    Lead Free (RoHS)

     
    DistributorRegionQty
    DIGI-KEYWorldwide0
    MOUSERWorldwide1
    $995.00 each1

    Description:

    The SP16160CH1RB demonstrates a high-IF sampling receiver subsystem that provides signal amplification, digitization and clocking as used in wireless infrastructure systems. The subsystem includes the ADC16DV160 analog-to-digital converter (ADC), LMH6517 Digitally-controlled Variable-Gain Amplifier (DVGA) and LMK04031B precision clock conditioner.

    Contents::

    • SP16160CH1RB reference board (for documentation see: RD-179)
    • ADC14PIC PIC loader board
      • Used for programming the LMK04031B
    • WaveVision 5 installation CD
      • Contains most recent Beta version of WaveVision 5 software (v5.0.5.175) and patch to support SP16160CH1RB
      • This kit requires the Wavevsn Brd 5.1 which must be purchased separately
    • Users Guide
    • Performance Plots



    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
    LM2734XMK/NOPB

    13.726
    13.851
    TSOT61260DetailDownloadN/A
    SFDB
    XTT
    LM2734XQMK/NOPB

    13.726
    TSOT61260DetailDownloadN/A
    SUKB
    XTT
    LM2734XQMKE/NOPB

    13.726
    TSOT61260DetailDownloadN/A
    SUKB
    XTT
    LM2734XQMKX/NOPB

    13.726
    TSOT61260DetailDownloadN/A
    SUKB
    XTT
    LM2734YMK/NOPB

    LM2734YMK
    13.726
    13.851
    TSOT61
    1
    260
    260
    DetailDownloadN/A
    SFEB
    XTT
    LM2734YMKX/NOPB

    LM2734YMKX
    13.726
    13.851
    TSOT61
    1
    260
    260
    DetailDownloadN/A
    SFEB
    XTT
    LM2734YQMK/NOPB

    13.726
    TSOT61260DetailDownloadN/A
    SVCB
    XTT
    LM2734YQMKE/NOPB

    13.726
    TSOT61260DetailDownloadN/A
    SVCB
    XTT
    LM2734YQMKX/NOPB

    13.726
    TSOT61260DetailDownloadN/A
    SVCB
    XTT

    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 LM2734.

    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 LM2734 is located at RoHS Status.

    Reliability Metrics
    Part Number Process EFR Reject EFR Sample Size PPM LTA Rejects LTA Device Hours FITS MTTF (Hours)
    LM2734XMKPVIP0500142800017550003497986041
    LM2734XQMKPVIP0500142800017550003497986041
    LM2734XQMKEPVIP0500142800017550003497986041
    LM2734XQMKXPVIP0500142800017550003497986041
    LM2734YMKPVIP0500142800017550003497986041
    LM2734YMKXPVIP0500142800017550003497986041
    LM2734YQMKPVIP0500142800017550003497986041
    LM2734YQMKEPVIP0500142800017550003497986041
    LM2734YQMKXPVIP0500142800017550003497986041

    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 LM2734.

    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 LM2734 is located at RoHS Status.

    Obsolete Versions
    Obsolete PartAlternate Part or SupplierSourceLast Time Buy Date
    LM2734XMFX
    LM2734XMKX
    NATIONAL SEMICONDUCTOR
    01 Dec 2009

    [Information as of 6-Feb-2012]