National Semiconductor | High-performance Analog

 

 LM2598   

SIMPLE SWITCHER Power Converter 150 KHz 1A Step-Down Voltage Regulator, with Features
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Features
  • 3.3V, 5V, 12V, and adjustable output versions
  • Adjustable version output voltage range, 1.2V to 37V ±4% max over line and load conditions
  • Guaranteed 1A output current
  • Available in 7-pin TO-220 and TO-263 (surface mount) package
  • Input voltage range up to 40V
  • Excellent line and load regulation specifications
  • 150 kHz fixed frequency internal oscillator
  • Shutdown# /Soft-start
  • Out of regulation error flag
  • Error output delay
  • Low power standby mode, IQ typically 85 µA
  • High Efficiency
  • Uses readily available standard inductors
  • Thermal shutdown and current limit protection
  • Description

    The LM2598 series of regulators are monolithic integrated circuits that provide all the active functions for a step-down (buck) switching regulator, capable of driving a 1A load with excellent line and load regulation. These devices are available in fixed output voltages of 3.3V, 5V, 12V, and an adjustable output version.

    This series of switching regulators is similar to the LM2595 series, with additional supervisory and performance features added.

    Requiring a minimum number of external components, these regulators are simple to use and include internal frequency compensation†, improved line and load specifications, fixed-frequency oscillator, Shutdown# /Soft-start, error flag delay and error flag output.

    The LM2598 series operates at a switching frequency of 150 kHz thus allowing smaller sized filter components than what would be needed with lower frequency switching regulators. Available in a standard 7-lead TO-220 package with several different lead bend options, and a 7-lead TO-263 surface mount package. Typically, for output voltages less than 12V, and ambient temperatures less than 50°C, no heat sink is required.

    A standard series of inductors (both through hole and surface mount types) are available from several different manufacturers optimized for use with the LM2598 series. This feature greatly simplifies the design of switch-mode power supplies.

    Other features include a guaranteed ±4% tolerance on output voltage under all conditions of input voltage and output load conditions, and ±15% on the oscillator frequency. External shutdown is included, featuring typically 85 µA standby current. Self protection features include a two stage current limit for the output switch and an over temperature shutdown for complete protection under fault conditions.


    Applications

  • Simple high-efficiency step-down (buck) regulator
  • Efficient pre-regulator for linear regulators
  • On-card switching regulators
  • Positive to Negative converter
  • WEBENCH® LM2598
        Min   Max   Range  
      VIN V    4.50 – 40.00V  
      VOUT V    1.23 – 40.00V  
      IOUT A    ≤ 1.00A  
      Ambient Temp °C    ≤ 100°C  
    Footprint BOM Cost Efficiency
    What are WEBENCH® tools?


    Also Recommended
    LM2672Higher Switching Frequency And Frequency Synchronization (400KHz)
    LM2590HVWider Input Voltage Range (4.5V To 60V)
    LM25993A Version Of LM2598
    LM28251A Totally Integarted Switching Power Supply IC



    Typical Application
    click for larger image


    Block Diagram
    click for larger image



    Typical Performance
    *click for larger image


    Parameters / ValuesLM2598 LM2672 LM2590HV LM2599 LM2825
    Output Current1000 mA 1000 mA 1000 mA 3000 mA 1000 mA
    Input Min Voltage4.5, 7, 4.75, 15 Volt 6.5 Volt 4.5 Volt 4.5, 7, 4.75, 15 Volt 4.5, 7, 4.75, 15 Volt
    Input Max Voltage40 Volt 40 Volt 60 Volt 40 Volt 40 Volt
    Output Min3.3, 1.23, 12, 5 Volt 1.23 Volt 3.3, 1.23, 5 Volt 3.3, 1.23, 12, 5 Volt 7, 3.3, 1.23, 12, 5 Volt
    Output Max3.3, 37, 12, 5 Volt 37 Volt 57, 3.3, 5 Volt 3.3, 37, 12, 5 Volt 3.3, 12, 15, 8, 5 Volt
    Frequency Min150 kHz 260 kHz 150 kHz 150 kHz 150 kHz
    Frequency Max150 kHz 260 kHz 150 kHz 150 kHz 150 kHz
    Efficiency (peak)90, 78, 82 % 90 % 77, 76, 82 % 90 % 80, 78, 81 %
    On/Off PinYes Yes Yes Yes Yes
    PowerGood / Error FlagYes No Yes Yes No
    SoftStartYes Yes Yes Yes Yes
    Sync PinNo Yes No No No
    InvertingYes No Yes No
    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, No Yes Yes, No Yes, No No, Yes
    Adj Switch FrequencyNo No No No No
    PWM ModeVoltage Voltage with Vin Feedforward Voltage Voltage Voltage
    TopologyBuck Buck Buck Buck Buck
    Special FeaturesSIMPLE SWITCHER regulator, error output delay Internal Type 3 compensation, 1.5% output voltage accuracy, SIMPLE SWITCHER regulator SIMPLE SWITCHER regulator, error output delay SIMPLE SWITCHER regulator, error output delay Totally integrated switching power supply, no external components
    Step-DownYes Yes Yes Yes No, Yes
    Multiple Output CapabilityNo No No No No
    Output PowerUndefined Watt Undefined Watt Undefined Watt Undefined Watt Undefined Watt
    Output Voltage3.3, Undefined, 12, 5 Volt Undefined Volt 3.3, Undefined, 5 Volt 3.3, Undefined, 12, 5 Volt Undefined, 3.3, 12, 5 Volt
    Output Range5V, 12V, 1.23V to 37V, 3.3V 1.23V to 37V 5V, 3.3V, 1.23V to 57V 5V, 12V, 1.23V to 37V, 3.3V 12V, 3.3V, 1.23V to 8V, 5V, 7V to 15V
    Switching Frequency150 kHz 260 kHz 150 kHz 150 kHz 150 kHz
    Regulator FamilySIMPLE SWITCHER SIMPLE SWITCHER SIMPLE SWITCHER SIMPLE SWITCHER Undefined
    Synchronous RectificationNo No No No No
    Part Number(s)
    (NSID)
    Top ViewAvailabilityCurrent Reported StockBudgetary PricingPack
    Size
    LM2598S-12/NOPB

    LM2598S-12

    RoHS Status


    TO-263
    Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    ARROWWorldwide575
    AVNET-EMWorldwide115
    DIGI-KEYWorldwide76
    MOUSERWorldwide155
    TAYLORAmericas575
    $1.87 each at 1K+ pcsrail
    of
    45
    LM2598S-3.3/NOPB

    LM2598S-3.3

    RoHS Status


    TO-263
    Full production
    Lead Time: 6 weeks

    Samples
    DistributorRegionQty
    AVNET-EMWorldwide180
    DIGI-KEYWorldwide207
    MOUSERWorldwide180
    RS COMPONENTSWorldwide14
    $1.87 each at 1K+ pcsrail
    of
    45
    LM2598S-5.0/NOPB

    LM2598S-5.0

    RoHS Status


    TO-263
    Full production
    Lead Time: 6 weeks

    Samples
    DistributorRegionQty
    AVNET-EMWorldwide185
    DIGI-KEYWorldwide291
    MOUSERWorldwide154
    $1.87 each at 1K+ pcsrail
    of
    45
    LM2598S-ADJ/NOPB

    LM2598S-ADJ

    RoHS Status


    TO-263
    Full production
    Lead Time: 6 weeks

    Samples
    DistributorRegionQty
    DIGI-KEYWorldwide830
    MOUSERWorldwide135
    $1.87 each at 1K+ pcsrail
    of
    45
    LM2598SX-12/NOPB

    LM2598SX-12

    RoHS Status


    TO-263
    Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    AVNET-EMWorldwide500
    DIGI-KEYWorldwide0
    MOUSERWorldwide500
    $1.87 each at 1K+ pcsreel
    of
    500
    LM2598SX-3.3/NOPB

    LM2598SX-3.3

    RoHS Status


    TO-263
    Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    DIGI-KEYWorldwide0
    MOUSERWorldwide500
    $1.87 each at 1K+ pcsreel
    of
    500
    LM2598SX-5.0/NOPB

    LM2598SX-5.0

    RoHS Status


    TO-263
    Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    DIGI-KEYWorldwide0
    MOUSERWorldwide500
    $1.87 each at 1K+ pcsreel
    of
    500
    LM2598SX-ADJ/NOPB

    LM2598SX-ADJ

    RoHS Status


    TO-263
    Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    DIGI-KEYWorldwide0
    $1.87 each at 1K+ pcsreel
    of
    500
    LM2598T-12/NOPB

    LM2598T-12

    RoHS Status


    TO-220
    Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    DIGI-KEYWorldwide0
    RSL MICROAsia Pacific585
    $1.87 each at 1K+ pcsrail
    of
    45
    LM2598T-3.3/NOPB

    LM2598T-3.3

    RoHS Status


    TO-220
    Full production
    Lead Time: 6 weeks

    Samples
    DistributorRegionQty
    DIGI-KEYWorldwide180
    MOUSERWorldwide180
    $1.87 each at 1K+ pcsrail
    of
    45
    LM2598T-5.0/NOPB

    LM2598T-5.0

    RoHS Status


    TO-220
    Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    DIGI-KEYWorldwide0
    RS COMPONENTSWorldwide18
    $1.87 each at 1K+ pcsrail
    of
    45
    LM2598T-ADJ/NOPB

    LM2598T-ADJ

    RoHS Status


    TO-220
    Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    DIGI-KEYWorldwide0
    $1.87 each at 1K+ pcsrail
    of
    45

    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 LM2598.

    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 LM2598 is located at RoHS Status.

    Part Number(s)
    (NSID)
    Weight
    (milligrams)
    TypePinsMSL RatingPeak ReflowRoHS
    Status
    CAD SymbolsModelsPackage
    Marking
    Format
    LM2598S-12/NOPB

    LM2598S-12
    1608.332
    1609.822
    TO-26373
    3
    245
    235
    DetailDownloadN/A
    NSUZXYTTE#
    LM2598S
    -12 P+
    LM2598S-3.3/NOPB

    LM2598S-3.3
    1608.332
    1609.822
    TO-26373
    3
    245
    235
    DetailDownloadN/A
    NSUZXYTTE#
    LM2598S
    -3.3 P+
    LM2598S-5.0/NOPB

    LM2598S-5.0
    1608.332
    1609.822
    TO-26373
    3
    245
    235
    DetailDownloadN/A
    NSUZXYTTE#
    LM2598S
    -5.0 P+
    LM2598S-ADJ/NOPB

    LM2598S-ADJ
    1608.332
    1609.822
    TO-26373
    3
    245
    235
    DetailDownloadN/A
    NSUZXYTTE#
    LM2598S
    -ADJ P+
    LM2598SX-12/NOPB

    LM2598SX-12
    1608.332
    1609.822
    TO-26373
    3
    245
    235
    DetailDownloadN/A
    NSUZXYTTE#
    LM2598S
    -12 P+
    LM2598SX-3.3/NOPB

    LM2598SX-3.3
    1608.332
    1609.822
    TO-26373
    3
    245
    235
    DetailDownloadN/A
    NSUZXYTTE#
    LM2598S
    -3.3 P+
    LM2598SX-5.0/NOPB

    LM2598SX-5.0
    1608.332
    1609.822
    TO-26373
    3
    245
    235
    DetailDownloadN/A
    NSUZXYTTE#
    LM2598S
    -5.0 P+
    LM2598SX-ADJ/NOPB

    LM2598SX-ADJ
    1608.332
    1609.822
    TO-26373
    3
    245
    235
    DetailDownloadN/A
    NSUZXYTTE#
    LM2598S
    -ADJ P+
    LM2598T-12/NOPB

    LM2598T-12
    1846.782
    1858.793
    TO-22071
    1
    NA
    NA
    DetailDownloadN/A
    NSUZXYTTE#
    LM2598T
    -12 P+
    LM2598T-3.3/NOPB

    LM2598T-3.3
    1846.782
    1858.793
    TO-22071
    1
    NA
    NA
    DetailDownloadN/A
    NSUZXYTTE#
    LM2598T
    -3.3 P+
    LM2598T-5.0/NOPB

    LM2598T-5.0
    1846.782
    1858.793
    TO-22071
    1
    NA
    NA
    DetailDownloadN/A
    NSUZXYTTE#
    LM2598T
    -5.0 P+
    LM2598T-ADJ/NOPB

    LM2598T-ADJ
    1846.782
    1858.793
    TO-22071
    1
    NA
    NA
    DetailDownloadN/A
    NSUZXYTTE#
    LM2598T
    -ADJ P+

    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 LM2598.

    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 LM2598 is located at RoHS Status.

    Design Tools
    TitleSizeDate
    SimpleSwitcher® DC-DC Converters Design Software  

    CAD Symbols and Models
    Download LM2598 CAD Symbols
     Models
    N/A


    Reliability Metrics
    Part Number Process EFR Reject EFR Sample Size PPM LTA Rejects LTA Device Hours FITS MTTF (Hours)
    LM2598S-12LB30003437100416450011181688246
    LM2598S-3.3LB30003437100416450011181688246
    LM2598S-5.0LB30003437100416450011181688246
    LM2598S-ADJLB30003437100416450011181688246
    LM2598SX-12LB30003437100416450011181688246
    LM2598SX-3.3LB30003437100416450011181688246
    LM2598SX-5.0LB30003437100416450011181688246
    LM2598SX-ADJLB30003437100416450011181688246
    LM2598T-12LB30003437100416450011181688246
    LM2598T-3.3LB30003437100416450011181688246
    LM2598T-5.0LB30003437100416450011181688246
    LM2598T-ADJLB30003437100416450011181688246

    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 LM2598.

    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 LM2598 is located at RoHS Status.

    [Information as of 9-Feb-2012]