National Semiconductor | High-performance Analog

 

 LM2577   
SIMPLE SWITCHER® Step-Up Voltage Regulator 		Click link to Download

Features
  • Requires few external components
  • NPN output switches 3.0A, can stand off 65V
  • Wide input voltage range: 3.5V to 40V
  • Current-mode operation for improved transient response, line regulation, and current limit
  • 52 kHz internal oscillator
  • Soft-start function reduces in-rush current during start-up
  • Output switch protected by current limit, under-voltage lockout, and thermal shutdown

    • Description

    The LM1577/LM2577 are monolithic integrated circuits that provide all of the power and control functions for step-up (boost), flyback, and forward converter switching regulators. The device is available in three different output voltage versions: 12V, 15V, and adjustable.

    Requiring a minimum number of external components, these regulators are cost effective, and simple to use. Listed in this data sheet are a family of standard inductors and flyback transformers designed to work with these switching regulators.

    Included on the chip is a 3.0A NPN switch and its associated protection circuitry, consisting of current and thermal limiting, and undervoltage lockout. Other features include a 52 kHz fixed-frequency oscillator that requires no external components, a soft start mode to reduce in-rush current during start-up, and current mode control for improved rejection of input voltage and output load transients.


    Applications

  • Simple boost regulator
  • Flyback and forward regulators
  • Multiple-output regulator

    • Also Recommended
    LM2585▲Higher Switching Frequency (100Khz - 200Khz)
    LM2586▲Additional Features, Higher Switching Frequency (100Khz - 200Khz)
    LM2587▲Higher Switching Frequency (100Khz - 200Khz), Higher Switch Current (5A)
    LM2588▲Additional Features, Higher Switching Frequency (100Khz - 200Khz), Higher Switch Current (5A)
    LM3224▲Higher Efficiency, Pin Selectable PWM Frequency Allowing Easy Filtering And Low Noise
    LM3478▲Higher Switch Current (10A) Controller
    LM5000▲Higher Frequency (300Khz To 1.25Mhz), 1.3A 80V Integrated Switch In Smaller Package

    Parameters / ValuesLM2577 LM2585 LM2586 LM2587 LM2588 LM3224 LM3478 LM5000
    Output Range15V, 1.23V min, 12V 1.23V min, 5V, 12V, 3.3V 1.23V min, 5V, 12V, 3.3V 1.23V min, 5V, 12V, 3.3V 1.23V min, 5V, 12V, 3.3V Vin to 20V 1.26V min 1.259V min.
    Switch Current3 Amp 3 Amp 3 Amp 5 Amp 5 Amp 2.6 Amp 2 Amp
    Input Min Voltage3.5 Volt 4 Volt 4 Volt 4 Volt 4 Volt 2.7 Volt 2.95 Volt 3.1 Volt
    Input Max Voltage40 Volt 40 Volt 40 Volt 40 Volt 40 Volt 7 Volt 40 Volt 40 Volt
    Feedback Voltage1.23, 12, 15 Volt 3.3, 1.23, 12, 5 Volt 3.3, 1.23, 12, 5 Volt 3.3, 1.23, 12, 5 Volt 3.3, 1.23, 12, 5 Volt 1.26 Volt 1.259 Volt
    Frequency Max52 kHz 100 kHz 200 kHz 100 kHz 200 kHz 1250 kHz 1000 kHz 1300 kHz
    Efficiency (peak)80 % 93, 80, 76 % 93, 80, 76 % 90, 75, 80 % 90, 75, 80 % 90 % 90 %
    Sync PinNo No Yes No Yes No No No
    Adj Switch FrequencyNo No Yes No Yes Yes Yes Yes
    Frequency Min52 kHz 100 kHz 100 kHz 100 kHz 100 kHz 615 kHz 100 kHz 300 kHz
    On/Off PinNo No Yes No Yes Yes Yes Yes
    PowerGood / Error FlagNo No No No No No No No
    SoftStartYes Yes Yes Yes Yes Yes Yes Yes
    Special FeaturesSIMPLE SWITCHER regulator SIMPLE SWITCHER regulator SIMPLE SWITCHER regulator SIMPLE SWITCHER regulator SIMPLE SWITCHER regulator Pin-selected switching frequency, External compensation, Ceramic cap stable, Flat panel display power, High current LED driver 80V internal switch, selectable frequency
    TopologyBoost, Flyback Boost, Flyback Boost, Flyback Boost, Flyback Boost, Flyback Boost Boost, Sepic, Flyback Flyback, Boost, Forward, SEPIC
    Step-UpYes Yes Yes Yes Yes Yes Yes Yes
    InvertingNo No No No No No No No
    FlybackYes Yes Yes Yes Yes Yes Yes Yes
    RegTypeSwitching Regulator Switching Regulator Switching Regulator Switching Regulator Switching Regulator Switching Regulator Switching Controller Switching Regulator
    Adjustable OutputNo, Yes Yes, No Yes, No Yes, No Yes, No Yes Yes Yes
    Temperature Min-40 deg C -40 deg C -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 125 deg C 125 deg C
    Regulator FamilySIMPLE SWITCHER SIMPLE SWITCHER SIMPLE SWITCHER SIMPLE SWITCHER SIMPLE SWITCHER
    Quiescent Current10 mA 11 mA 11 mA 11 mA 11 mA 1.3 mA 2.1 mA

    Datasheets
    TitleSizeDateOther
    Language
    LM2577 SIMPLE SWITCHER® Step-Up Voltage Regulator1406
    Kbytes    		14-Apr-05日本語  


    Application Notes
    TitleSizeDateOther
    Language
    AN-776: Application Note 776 20 Watt Simple Switcher Forward Converter459
    Kbytes    		26-Sep-02 
    AN-777: Application Note 777 LM2577 Three Output, Isolated Flyback Regulator112
    Kbytes    		26-Sep-02 


    Other Technical Documents
    TitleTypeDate
    Negative Buck Switching Regulator (using LM258x)App Note 2007-03-21
    Linear and Switching Voltage Regulator Fundamental Part 2Conference Paper 2007-03-21
    Practical Implementation of Negative-Input, Negative-Output Step-Down Switching ConvertersExternal Article 2007-07-27

    Part Number(s)
    (NSID)    		Top ViewAvailabilityCurrent Reported StockBudgetary PricingPack
    Size
    LM2577M-ADJ/NOPB

    LM2577M-ADJ

    RoHS Status

    SOIC WIDE    		Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    AVNET-EMWorldwide449
    DIGI-KEYWorldwide121
    MOUSERWorldwide120
    		$3.12 each at 1K+ pcsrail
    of
    30
    LM2577N-ADJ/NOPB

    LM2577N-ADJ

    RoHS Status

    MDIP    		Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    DIGI-KEYWorldwide216
    FARNELLEurope and Asia27
    MOUSERWorldwide146
    NEWARKAmericas27
    		$3.12 each at 1K+ pcsrail
    of
    20
    LM2577S-12/NOPB

    LM2577S-12

    RoHS Status

    TO-263    		Full production
    Lead Time: 6 weeks

    Samples
    DistributorRegionQty
    ARROWWorldwide45
    AVNET-EMWorldwide78
    BRITESTONESouth Korea14
    DIGI-KEYWorldwide474
    MOUSERWorldwide132
    NEWARKAmericas37
    TAYLORAmericas45
    		$3.12 each at 1K+ pcsrail
    of
    45
    LM2577S-ADJ/NOPB

    LM2577S-ADJ

    RoHS Status

    TO-263    		Full production
    Lead Time: 6 weeks

    Samples
    DistributorRegionQty
    ARROWWorldwide245
    AVNET-EMWorldwide321
    BRITESTONESouth Korea357
    DIGI-KEYWorldwide254
    FARNELLEurope and Asia731
    MOUSERWorldwide395
    NEWARKAmericas363
    TAYLORAmericas412
    		$3.12 each at 1K+ pcsrail
    of
    45
    LM2577SX-12/NOPB

    LM2577SX-12

    RoHS Status

    TO-263    		Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    DIGI-KEYWorldwide0
    MOUSERWorldwide500
    		$3.12 each at 1K+ pcsreel
    of
    500
    LM2577SX-ADJ/NOPB

    LM2577SX-ADJ

    RoHS Status

    TO-263    		Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    ARROWWorldwide500
    DIGI-KEYWorldwide0
    MOUSERWorldwide464
    TAYLORAmericas500
    		$3.12 each at 1K+ pcsreel
    of
    500
    LM2577T-12/NOPB

    LM2577T-12

    RoHS Status

    TO-220    		Full production
    Lead Time: 6 weeks

    Samples
    DistributorRegionQty
    ARROWWorldwide90
    AVNET-EMWorldwide90
    DIGI-KEYWorldwide68
    FARNELLEurope and Asia63
    MOUSERWorldwide127
    NEWARKAmericas26
    RS COMPONENTSWorldwide53
    TAYLORAmericas90
    TECHMOSAAsia Pacific1800
    		$3.12 each at 1K+ pcsrail
    of
    45
    LM2577T-15/NOPB

    LM2577T-15

    RoHS Status

    TO-220    		Full production
    Lead Time: 6 weeks

     
    DistributorRegionQty
    ARROWWorldwide36
    AVNET-EMWorldwide165
    DIGI-KEYWorldwide236
    FARNELLEurope and Asia34
    MOUSERWorldwide127
    NEWARKAmericas34
    TAYLORAmericas36
    		$3.12 each at 1K+ pcsrail
    of
    45
    LM2577T-ADJ/NOPB

    LM2577T-ADJ

    RoHS Status

    TO-220    		Full production
    Lead Time: 6 weeks

    Samples
    DistributorRegionQty
    ARROWWorldwide5
    AVNET-EMWorldwide6352
    DIGI-KEYWorldwide1553
    FARNELLEurope and Asia252
    MOUSERWorldwide268
    NEWARKAmericas505
    RS COMPONENTSWorldwide40
    TAYLORAmericas1810
    		$3.12 each at 1K+ pcsrail
    of
    45

    Obsolete Versions
    Obsolete PartAlternate Part or SupplierSourceLast Time Buy Date
    LM2577-ADJ MDC
    		NONE
    		NATIONAL SEMICONDUCTOR
    		03 Dec 2008
    LM2577M-12
    		LM2577S-ADJ
    		NATIONAL SEMICONDUCTOR
    		01 Dec 2009
    LM2577M-15
    		LM2585S-ADJ
    		NATIONAL SEMICONDUCTOR
    		16 Nov 2008
    LM2577MX-12
    		LM2585SX-12
    		NATIONAL SEMICONDUCTOR
    		01 Dec 2009
    LM2577MX-15
    		LM2585SX-ADJ
    		NATIONAL SEMICONDUCTOR
    		16 Nov 2008
    LM2577MX-ADJ
    		LM2585SX-ADJ
    		NATIONAL SEMICONDUCTOR
    		01 Dec 2009
    LM2577N-12
    		LM2585S-12
    		NATIONAL SEMICONDUCTOR
    		01 Dec 2009
    LM2577N-15
    		LM2585S-ADJ
    		NATIONAL SEMICONDUCTOR
    		16 Nov 2008
    LM2577S-15
    		LM2585S-ADJ
    		NATIONAL SEMICONDUCTOR
    		16 Nov 2008
    LM2577SX-15
    		LM2585SX-ADJ
    		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 LM2577.

    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 LM2577 is located at RoHS Status.

    Part Number(s)
    (NSID)    		Weight
    (milligrams)    		TypePinsMSL RatingPeak ReflowRoHS
    Status    		CAD SymbolsModelsPackage
    Marking
    Format
    LM2577M-ADJ/NOPB

    LM2577M-ADJ
    		628.76
    630.001
    		SOIC WIDE243
    3    		260
    260    		DetailN/AN/A
    		NSUZXYTTE#
    LM2577M
    -ADJ P+
    LM2577N-ADJ/NOPB

    LM2577N-ADJ
    		1219.322
    1223.032
    		MDIP161
    1    		NA
    NA    		DetailN/AN/A
    		NSUZXYYTTE#
    LM2577N-ADJ
    P+
    LM2577S-12/NOPB

    LM2577S-12
    		1448.647
    1449.868
    		TO-26353
    3    		245
    235    		DetailN/AN/A
    		NSUZXYTTE#
    LM2577S
    -12 P+
    LM2577S-ADJ/NOPB

    LM2577S-ADJ
    		1448.647
    1449.868
    		TO-26353
    3    		245
    235    		DetailN/AN/A
    		NSUZXYTTE#
    LM2577S
    -ADJ P+
    LM2577SX-12/NOPB

    LM2577SX-12
    		1448.647
    1449.868
    		TO-26353
    3    		245
    235    		DetailN/AN/A
    		NSUZXYTTE#
    LM2577S
    -12 P+
    LM2577SX-ADJ/NOPB

    LM2577SX-ADJ
    		1448.647
    1449.868
    		TO-26353
    3    		245
    235    		DetailN/AN/A
    		NSUZXYTTE#
    LM2577S
    -ADJ P+
    LM2577T-12/NOPB

    LM2577T-12
    		1905.986
    1908.876
    		TO-22051
    1    		NA
    NA    		DetailN/AN/A
    		NSUZXYTTE#
    LM2577T-12
    P+
    LM2577T-15/NOPB

    LM2577T-15
    		1905.986
    1908.876
    		TO-22051
    1    		NA
    NA    		DetailN/AN/A
    		NSUZXYTTE#
    LM2577T-15
    P+
    LM2577T-ADJ/NOPB

    LM2577T-ADJ
    		1907.045
    1908.876
    		TO-22051
    1    		NA
    NA    		DetailN/AN/A
    		NSUZXYTTE#
    LM2577T
    -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 LM2577.

    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 LM2577 is located at RoHS Status.

    Design Tools
    TitleSizeDate
    SimpleSwitcher® DC-DC Converters Design Software  

    CAD Symbols and Models
    N/A
    		 Models
    N/A


    Reliability Metrics
    Part Number Process EFR Reject EFR Sample Size PPM LTA Rejects LTA Device Hours FITS MTTF (Hours)
    LM2577M-ADJSLM04404600353250011002356520
    LM2577N-ADJSLM04404600353250011002356520
    LM2577S-12SLM04404600353250011002356520
    LM2577S-ADJSLM04404600353250011002356520
    LM2577SX-12SLM04404600353250011002356520
    LM2577SX-ADJSLM04404600353250011002356520
    LM2577T-12SLM04404600353250011002356520
    LM2577T-15SLM04404600353250011002356520
    LM2577T-ADJSLM04404600353250011002356520

    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 LM2577.

    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 LM2577 is located at RoHS Status.

    Obsolete Versions
    Obsolete PartAlternate Part or SupplierSourceLast Time Buy Date
    LM2577-ADJ MDC
    		NONE
    		NATIONAL SEMICONDUCTOR
    		03 Dec 2008
    LM2577M-12
    		LM2577S-ADJ
    		NATIONAL SEMICONDUCTOR
    		01 Dec 2009
    LM2577M-15
    		LM2585S-ADJ
    		NATIONAL SEMICONDUCTOR
    		16 Nov 2008
    LM2577MX-12
    		LM2585SX-12
    		NATIONAL SEMICONDUCTOR
    		01 Dec 2009
    LM2577MX-15
    		LM2585SX-ADJ
    		NATIONAL SEMICONDUCTOR
    		16 Nov 2008
    LM2577MX-ADJ
    		LM2585SX-ADJ
    		NATIONAL SEMICONDUCTOR
    		01 Dec 2009
    LM2577N-12
    		LM2585S-12
    		NATIONAL SEMICONDUCTOR
    		01 Dec 2009
    LM2577N-15
    		LM2585S-ADJ
    		NATIONAL SEMICONDUCTOR
    		16 Nov 2008
    LM2577S-15
    		LM2585S-ADJ
    		NATIONAL SEMICONDUCTOR
    		16 Nov 2008
    LM2577SX-15
    		LM2585SX-ADJ
    		NATIONAL SEMICONDUCTOR
    		16 Nov 2008

    [Information as of 6-Feb-2012]
    Copyright © 2011 National Semiconductor Corporation