National Semiconductor | High-performance Analog

 

 LM2672   

SIMPLE SWITCHER Power Converter High Efficiency 1A Step-Down Voltage Regulator with Features
Click link to Download

Features

  • Efficiency up to 96%
  • Available in SO-8, 8-pin DIP and LLP packages
  • Computer Design Software LM267X Made Simple version 6.0
  • Simple and easy to design with
  • Requires only 5 external components
  • Uses readily available standard inductors
  • 3.3V, 5.0V, 12V, and adjustable output versions
  • Adjustable version output voltage range: 1.21V to 37V
  • ±1.5% max output voltage tolerance over line and load conditions
  • Guaranteed 1A output load current
  • 0.25Ω DMOS Output Switch
  • Wide input voltage range: 8V to 40V
  • 260 kHz fixed frequency internal oscillator
  • TTL shutdown capability, low power standby mode
  • Soft-start and frequency synchronization
  • Thermal shutdown and current limit protection
  • Description

    The LM2672 series of regulators are monolithic integrated circuits built with a LMDMOS process. These regulators provide all the active functions for a step-down (buck) switching regulator, capable of driving a 1A load current with excellent line and load regulation. These devices are available in fixed output voltages of 3.3V, 5.0V, 12V, and an adjustable output version.

    Requiring a minimum number of external components, these regulators are simple to use and include patented internal frequency compensation (Patent Nos. 5,382,918 and 5,514,947), fixed frequency oscillator, external shutdown, soft-start, and frequency synchronization.

    The LM2672 series operates at a switching frequency of 260 kHz, thus allowing smaller sized filter components than what would be needed with lower frequency switching regulators. Because of its very high efficiency (>90%), the copper traces on the printed circuit board are the only heat sinking needed.

    A family of standard inductors for use with the LM2672 are available from several different manufacturers. This feature greatly simplifies the design of switch-mode power supplies using these advanced ICs. Also included in the datasheet are selector guides for diodes and capacitors designed to work in switch-mode power supplies.

    Other features include a guaranteed ±1.5% tolerance on output voltage within specified input voltages and output load conditions, and ±10% on the oscillator frequency. External shutdown is included, featuring typically 50 μA stand-by current. The output switch includes current limiting, as well as thermal shutdown for full protection under fault conditions.

    To simplify the LM2672 buck regulator design procedure, there exists computer design software, LM267X Made Simple version 6.0.

    See Layout Guidelines

    WEBENCH® LM2672
        Min   Max   Range  
      VIN V    6.50 – 40.00V  
      VOUT V    1.21 – 40.00V  
      IOUT A    ≤ 1.00A  
      Ambient Temp °C    ≤ 100°C  
    Footprint BOM Cost Efficiency
    What are WEBENCH® tools?


    Also Recommended
    LM22672Wider Input Voltage Range (4.5V To 42V), Fixed 500kHz Or Adjustable Up To 1MHz
    LM25575Fast Transient Response And Higher Current (1.5A) And Higher Switching Frequency (Up To 1M
    LM26703A Output Current
    LM5575Wider Input Voltage Range (6 To 75V), Higher Current (1.5A) And Higher Switching Frequency (Up To 50



    Typical Application
    click for larger image


    Block Diagram
    click for larger image



    Typical Performance
    *click for larger image


    Parameters / ValuesLM2672 LM22672 LM25575 LM2670 LM5575
    Output Current1000 mA 1000 mA 1500 mA 3000 mA 1500 mA
    Input Min Voltage6.5 Volt 4.5 Volt 6 Volt 8 Volt 6 Volt
    Input Max Voltage40 Volt 42 Volt 42 Volt 40 Volt 75 Volt
    Output Min1.23 Volt 1.285 Volt 1.23 Volt 1.23 Volt 1.23 Volt
    Output Max37 Volt 40 Volt 37 Volt 70 Volt
    Frequency Min260 kHz 200 kHz 50 kHz 260 kHz 50 kHz
    Frequency Max260 kHz 1000 kHz 1000 kHz 260 kHz 500 kHz
    Efficiency (peak)90 % 92 % 91 % 94 % 87 %
    On/Off PinYes Yes Yes Yes Yes
    PowerGood / Error FlagNo No No No No
    SoftStartYes Yes Yes No Yes
    Sync PinYes Yes Yes Yes Yes
    FlybackNo No No No No
    RegTypeSwitching 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
    Temperature Max125 deg C 125 deg C 125 deg C 125 deg C 125 deg C
    Adjustable OutputYes Yes Yes No Yes
    Adj Switch FrequencyNo Yes Yes No Yes
    PWM ModeVoltage with Vin Feedforward Voltage Mode Control Current Voltage with Vin Feedforward Current
    TopologyBuck Buck Buck Buck Buck
    Special FeaturesInternal Type 3 compensation, 1.5% output voltage accuracy, SIMPLE SWITCHER regulator 500 kHz Default Switching Frequency 1.5% feedback voltage accuracy, emulated current mode Internal Type 3 compensation, 2% output voltage accuracy, SIMPLE SWITCHER regulator 1.5% feedback voltage accuracy, emulated current mode
    Step-DownYes Yes Yes Yes Yes
    Multiple Output CapabilityNo No No No No
    Output PowerUndefined Watt Undefined Watt Undefined Watt Undefined Watt
    Output VoltageUndefined Volt Undefined Volt 12 Volt Undefined Volt
    Output Range1.23V to 37V 1.23V to 37V 12V 1.23V to 70V
    Switching Frequency260 kHz 500 kHz 1000 kHz 260 kHz 500 kHz
    Regulator FamilySIMPLE SWITCHER SIMPLE SWITCHER SIMPLE SWITCHER SIMPLE SWITCHER SIMPLE SWITCHER
    Synchronous RectificationNo No No No No

    Datasheets
    TitleSizeDateOther
    Language
    LM2672 SIMPLE SWITCHER Power Converter High Efficiency 1A Step-Down Voltage Regulator with Features626
    Kbytes
    8-Mar-07日本語  


    Other Technical Documents
    TitleTypeDate
    Simple Techniques Minimize Cross-Coupling in Distributed Power SystemsApp Note 2007-03-21

    Part Number(s)
    (NSID)
    Top ViewAvailabilityCurrent Reported StockBudgetary PricingPack
    Size
    LM2672LD-ADJ/NOPB

    LM2672LD-ADJ

    RoHS Status


    LLP
    Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    ARROWWorldwide1000
    AVNET-EMWorldwide1000
    DIGI-KEYWorldwide0
    MOUSERWorldwide1000
    TAYLORAmericas1000
    $1.78 each at 1K+ pcsreel
    of
    1000
    LM2672M-12/NOPB

    LM2672M-12

    RoHS Status


    SOIC NARROW
    Full production
    Lead Time: 6 weeks

    Samples
    DistributorRegionQty
    AVNET-EMWorldwide155
    DIGI-KEYWorldwide469
    MOUSERWorldwide184
    NEWARKAmericas220
    RS COMPONENTSWorldwide16
    $1.78 each at 1K+ pcsrail
    of
    95
    LM2672M-3.3/NOPB

    LM2672M-3.3

    RoHS Status


    SOIC NARROW
    Full production
    Lead Time: 6 weeks

    Samples
    DistributorRegionQty
    ARROWWorldwide475
    AVNET-EMWorldwide100
    DIGI-KEYWorldwide598
    MOUSERWorldwide63
    NEWARKAmericas180
    RS COMPONENTSWorldwide76
    TAYLORAmericas475
    $1.78 each at 1K+ pcsrail
    of
    95
    LM2672M-5.0/NOPB

    LM2672M-5.0

    RoHS Status


    SOIC NARROW
    Full production
    Lead Time: 6 weeks

    Samples
    DistributorRegionQty
    ARROWWorldwide292
    AVNET-EMWorldwide28
    DIGI-KEYWorldwide1795
    NEWARKAmericas515
    RS COMPONENTSWorldwide51
    TAYLORAmericas1830
    $1.78 each at 1K+ pcsrail
    of
    95
    LM2672M-ADJ/NOPB

    LM2672M-ADJ

    RoHS Status


    SOIC NARROW
    Full production
    Lead Time: 6 weeks

    Samples
    DistributorRegionQty
    ARROWWorldwide291
    AVNET-EMWorldwide2420
    DIGI-KEYWorldwide2578
    FARNELLEurope and Asia2821
    MOUSERWorldwide2
    NEWARKAmericas3950
    RS COMPONENTSWorldwide100
    TAYLORAmericas2366
    $1.78 each at 1K+ pcsrail
    of
    95
    LM2672MX-12/NOPB

    LM2672MX-12

    RoHS Status


    SOIC NARROW
    Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    DIGI-KEYWorldwide0
    $1.78 each at 1K+ pcsreel
    of
    2500
    LM2672MX-3.3/NOPB

    LM2672MX-3.3

    RoHS Status


    SOIC NARROW
    Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    AVNET-EMWorldwide5000
    DIGI-KEYWorldwide0
    $1.78 each at 1K+ pcsreel
    of
    2500
    LM2672MX-5.0/NOPB

    LM2672MX-5.0

    RoHS Status


    SOIC NARROW
    Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    ARROWWorldwide7500
    DIGI-KEYWorldwide0
    MOUSERWorldwide1360
    NEWARKAmericas1852
    TAYLORAmericas12200
    $1.78 each at 1K+ pcsreel
    of
    2500
    LM2672MX-ADJ/NOPB

    LM2672MX-ADJ

    RoHS Status


    SOIC NARROW
    Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    ARROWWorldwide2500
    AVNET-EMWorldwide2500
    DIGI-KEYWorldwide0
    FARNELLEurope and Asia1205
    MOUSERWorldwide2390
    NEWARKAmericas1205
    RSL MICROAsia Pacific5000
    TAYLORAmericas2500
    $1.78 each at 1K+ pcsreel
    of
    2500
    LM2672N-12/NOPB

    LM2672N-12

    RoHS Status


    MDIP
    Full production
    Lead Time: 6 weeks

    Samples
    DistributorRegionQty
    AVNET-EMWorldwide136
    DIGI-KEYWorldwide8
    MOUSERWorldwide200
    $1.78 each at 1K+ pcsrail
    of
    40
    LM2672N-3.3/NOPB

    LM2672N-3.3

    RoHS Status


    MDIP
    Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    DIGI-KEYWorldwide0
    MOUSERWorldwide200
    $1.78 each at 1K+ pcsrail
    of
    40
    LM2672N-5.0/NOPB

    LM2672N-5.0

    RoHS Status


    MDIP
    Full production
    Lead Time: 6 weeks

    Samples
    DistributorRegionQty
    ARROWWorldwide611
    AVNET-EMWorldwide138
    DIGI-KEYWorldwide425
    MOUSERWorldwide195
    RS COMPONENTSWorldwide28
    TAYLORAmericas621
    $1.78 each at 1K+ pcsrail
    of
    40
    LM2672N-ADJ/NOPB

    LM2672N-ADJ

    RoHS Status


    MDIP
    Full production
    Lead Time: 6 weeks

    Samples
    DistributorRegionQty
    ARROWWorldwide200
    AVNET-EMWorldwide200
    DIGI-KEYWorldwide198
    FARNELLEurope and Asia34
    MOUSERWorldwide200
    RS COMPONENTSWorldwide38
    TAYLORAmericas200
    $1.78 each at 1K+ pcsrail
    of
    40

    Obsolete Versions
    Obsolete PartAlternate Part or SupplierSourceLast Time Buy Date
    LM2672LD-12
    LT1376
    LINEAR TECHNOLOGY CORPORATION
    16 Nov 2008
    LM2672LD-3.3
    LT1375
    LINEAR TECHNOLOGY CORPORATION
    16 Nov 2008
    LM2672LD-5.0
    LT1375
    LINEAR TECHNOLOGY CORPORATION
    16 Nov 2008
    LM2672LDX-12
    LT1375
    LINEAR TECHNOLOGY CORPORATION
    16 Nov 2008
    LM2672LDX-3.3
    MAX738A
    MAXIM
    16 Nov 2008
    LM2672LDX-5.0
    L4972A
    SGS THOMSON
    16 Nov 2008
    LM2672LDX-ADJ
    LT1375
    LINEAR TECHNOLOGY CORPORATION
    16 Nov 2008
    LM2672MX-ADJEP
    NONE
    NATIONAL SEMICONDUCTOR
    16 Nov 2008

    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 LM2672.

    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 LM2672 is located at RoHS Status.

    Part Number(s)
    (NSID)
    Weight
    (milligrams)
    TypePinsMSL RatingPeak ReflowRoHS
    Status
    CAD SymbolsModelsPackage
    Marking
    Format
    LM2672LD-ADJ/NOPB

    LM2672LD-ADJ
    63.133
    63.38
    LLP163
    1
    260
    235
    DetailDownloadN/A
    NS
    UZXYTT
    S0004B
    LM2672M-12/NOPB

    LM2672M-12
    69.761
    70.001
    SOIC NARROW81
    1
    260
    235
    DetailDownloadN/A
    NSZXTT
    2672
    M-12
    LM2672M-3.3/NOPB

    LM2672M-3.3
    69.761
    70.001
    SOIC NARROW81
    1
    260
    235
    DetailDownloadN/A
    NSZXTT
    2672
    M3.3
    LM2672M-5.0/NOPB

    LM2672M-5.0
    69.761
    70.001
    SOIC NARROW81
    1
    260
    235
    DetailDownloadN/A
    NSZXTT
    2672
    M5.0
    LM2672M-ADJ/NOPB

    LM2672M-ADJ
    69.761
    70.001
    SOIC NARROW81
    1
    260
    235
    DetailDownloadN/A
    NSZXTT
    2672
    MADJ
    LM2672MX-12/NOPB

    LM2672MX-12
    69.761
    70.001
    SOIC NARROW81
    1
    260
    235
    DetailDownloadN/A
    NSZXTT
    2672
    M-12
    LM2672MX-3.3/NOPB

    LM2672MX-3.3
    69.761
    70.001
    SOIC NARROW81
    1
    260
    235
    DetailDownloadN/A
    NSZXTT
    2672
    M3.3
    LM2672MX-5.0/NOPB

    LM2672MX-5.0
    69.761
    70.001
    SOIC NARROW81
    1
    260
    235
    DetailDownloadN/A
    NSZXTT
    2672
    M5.0
    LM2672MX-ADJ/NOPB

    LM2672MX-ADJ
    69.761
    70.001
    SOIC NARROW81
    1
    260
    235
    DetailDownloadN/A
    NSZXTT
    2672
    MADJ
    LM2672N-12/NOPB

    LM2672N-12
    508.252
    510.002
    MDIP81
    1
    NA
    NA
    DetailDownloadN/A
    NSUZXYTTE#
    LM2672
    N-12
    LM2672N-3.3/NOPB

    LM2672N-3.3
    508.252
    510.002
    MDIP81
    1
    NA
    NA
    DetailDownloadN/A
    NSUZXYTTE#
    LM2672
    N-3.3
    LM2672N-5.0/NOPB

    LM2672N-5.0
    508.252
    510.002
    MDIP81
    1
    NA
    NA
    DetailDownloadN/A
    NSUZXYTTE#
    LM2672
    N-5.0
    LM2672N-ADJ/NOPB

    LM2672N-ADJ
    508.252
    510.002
    MDIP81
    1
    NA
    NA
    DetailDownloadN/A
    NSUZXYTTE#
    LM2672
    N-ADJ

    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 LM2672.

    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 LM2672 is located at RoHS Status.

    Design Tools
    TitleSizeDate
    SimpleSwitcher® DC-DC Converters Design Software  

    CAD Symbols and Models
    Download LM2672 CAD Symbols
     Models
    N/A


    Reliability Metrics
    Part Number Process EFR Reject EFR Sample Size PPM LTA Rejects LTA Device Hours FITS MTTF (Hours)
    LM2672LD-ADJLMDMOS0182950026500002751944735
    LM2672M-12LMDMOS0182950026500002751944735
    LM2672M-3.3LMDMOS0182950026500002751944735
    LM2672M-5.0LMDMOS0182950026500002751944735
    LM2672M-ADJLMDMOS0182950026500002751944735
    LM2672MX-12LMDMOS0182950026500002751944735
    LM2672MX-3.3LMDMOS0182950026500002751944735
    LM2672MX-5.0LMDMOS0182950026500002751944735
    LM2672MX-ADJLMDMOS0182950026500002751944735
    LM2672N-12LMDMOS0182950026500002751944735
    LM2672N-3.3LMDMOS0182950026500002751944735
    LM2672N-5.0LMDMOS0182950026500002751944735
    LM2672N-ADJLMDMOS0182950026500002751944735

    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 LM2672.

    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 LM2672 is located at RoHS Status.

    Obsolete Versions
    Obsolete PartAlternate Part or SupplierSourceLast Time Buy Date
    LM2672LD-12
    LT1376
    LINEAR TECHNOLOGY CORPORATION
    16 Nov 2008
    LM2672LD-3.3
    LT1375
    LINEAR TECHNOLOGY CORPORATION
    16 Nov 2008
    LM2672LD-5.0
    LT1375
    LINEAR TECHNOLOGY CORPORATION
    16 Nov 2008
    LM2672LDX-12
    LT1375
    LINEAR TECHNOLOGY CORPORATION
    16 Nov 2008
    LM2672LDX-3.3
    MAX738A
    MAXIM
    16 Nov 2008
    LM2672LDX-5.0
    L4972A
    SGS THOMSON
    16 Nov 2008
    LM2672LDX-ADJ
    LT1375
    LINEAR TECHNOLOGY CORPORATION
    16 Nov 2008
    LM2672MX-ADJEP
    NONE
    NATIONAL SEMICONDUCTOR
    16 Nov 2008

    [Information as of 7-Feb-2012]