LM1577

LM2577SX-ADJNOPB TI1 | Alldatasheet

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LM1577,LM2577 www.ti.com SNOS658D –JUNE 1999–REVISED APRIL 2013 LM1577/LM2577SIMPLESWITCHER® Step-UpVoltageRegulator Check forSamples: LM1577 ,LM2577 1FEATURES DESCRIPTION The LM1577/LM2577 are monolithicintegrated 23• RequiresFew ExternalComponents circuitsthatprovideallof the power and control• NPN Output Switches 3.0A,can Stand off65V functionsforstep-up(boost),flyback,and forward

• Wide InputVoltageRange: 3.5Vto40V converter switching regulators.The device is availablein threedifferentoutputvoltageversions:• Current-mode OperationforImproved 12V,15V,and adjustable.TransientResponse, LineRegulation,and CurrentLimit Requiring a minimum number of external components,theseregulatorsare costeffective,and• 52 kHz InternalOscillator simpletouse.Listedinthisdatasheetarea familyof• Soft-startFunctionReduces In-rushCurrent standardinductorsand flybacktransformersdesignedDuring Start-up towork withtheseswitchingregulators.
• Output Switch Protectedby CurrentLimit, Includedon the chipisa 3.0A NPN switchand itsUnder-voltageLockout,and Thermal associatedprotectioncircuitry,consistingof currentShutdown and thermallimiting,and undervoltagelockout.Other featuresincludea 52 kHz fixed-frequencyoscillatorTYPICAL APPLICATIONS thatrequiresno externalcomponents, a softstart mode to reduce in-rushcurrentduringstart-up,and• Simple Boost Regulator currentmode controlforimprovedrejectionof input• Flybackand Forward Regulators voltageand outputloadtransients.
• Multiple-outputRegulator Connection Diagrams Figure1. 5-Lead (StraightLeads) TO-220 (T)– Top Figure2.5-Lead (Bent,Staggered Leads) TO-220 View (T)– Top View See Package Number KC See Package Number NDH0005D Pleasebe aware thatan importantnoticeconcerningavailability,standardwarranty,and use incriticalapplicationsof Texas Instrumentssemiconductorproductsand disclaimerstheretoappearsattheend ofthisdatasheet. 2SIMPLE SWITCHER isa registeredtrademarkofTexas Instruments. 3Allothertrademarksarethepropertyoftheirrespectiveowners. PRODUCTION DATA informationiscurrentas ofpublicationdate. Copyright© 1999–2013,Texas InstrumentsIncorporatedProductsconform to specificationsper the terms of the Texas Instrumentsstandardwarranty.Productionprocessingdoes not necessarilyincludetestingofallparameters.

LM1577,LM2577 SNOS658D –JUNE 1999–REVISED APRIL 2013 www.ti.com *No InternalConnection *No internalConnection Figure3.16-Lead PDIP (N)– Top View Figure4.24-Lead SOIC Package (M)– Top View See Package Number NBG0016G See Package Number DW Figure5.5-Lead DDPAK/TO-263 (S)SFM Package – Figure6.5-Lead DDPAK/TO-263 (S)SFM Package – Top View Side View See Package Number KTT0005B Figure7. 4-Lead TO-220 (K)– Bottom View See Package Number NEB0005B TypicalApplication Note:Pinnumbers shown areforTO-220 (T)package. These deviceshave limitedbuilt-inESD protection.The leadsshouldbe shortedtogetherorthedeviceplacedinconductivefoam duringstorageorhandlingtopreventelectrostaticdamage totheMOS gates.

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LM1577,LM2577 www.ti.com SNOS658D –JUNE 1999–REVISED APRIL 2013 AbsoluteMaximum Ratings(1)(2) SupplyVoltage 45V OutputSwitchVoltage 65V OutputSwitchCurrent(3) 6.0A Power Dissipation InternallyLimited StorageTemperatureRange −65°C to+150°C Lead Temperature Soldering,10 sec. 260°C Maximum JunctionTemperature 150°C Minimum ESD Rating C = 100 pF,R = 1.5kΩ 2 kV (1) AbsoluteMaximum Ratingsindicatelimitsbeyond whichdamage tothedevicemay occur.Operatingratingsindicateconditionsthe deviceisintendedtobe functional,butdeviceparameterspecificationsmay notbe ensuredundertheseconditions.Forensured specificationsand testconditions,see theElectricalCharacteristics. (2) IfMilitary/Aerospacespecifieddevicesarerequired,pleasecontacttheTexas InstrumentsSalesOffice/Distributorsforavailabilityand specifications. (3) Due totimingconsiderationsoftheLM1577/LM2577 currentlimitcircuit,outputcurrentcannotbe internallylimitedwhen the LM1577/LM2577 isused as a step-upregulator.To preventdamage totheswitch,itscurrentmust be externallylimitedto6.0A. However,outputcurrentisinternallylimitedwhen theLM1577/LM2577 isused as a flybackorforwardconverterregulatorinaccordance totheApplicationHints. OperatingRatings SupplyVoltage 3.5V≤ VIN ≤ 40V OutputSwitchVoltage 0V ≤ VSWITCH ≤ 60V OutputSwitchCurrent ISWITCH ≤ 3.0A JunctionTemperatureRange LM1577 −55°C ≤ TJ ≤ +150°C LM2577 −40°C ≤ TJ ≤ +125°C SpecificationswithstandardtypefaceareforTJ = 25°C, and thoseinbold typefaceapplyoverfullOperatingTemperature Range .Unlessotherwisespecified,VIN = 5V,and ISWITCH = 0. Symbol Parameter Conditions Typical LM1577-12 LM2577-12 Units Limit(1)(2) Limit(3) (Limits) SYSTEM PARAMETERS CircuitofFigure29(4) VOUT OutputVoltage VIN = 5V to10V 12.0 V ILOAD = 100 mA to800 mA (1) LineRegulation VIN = 3.5Vto10V 20 mV ILOAD = 300 mA 50/100 50/100 mV(max)(1) Load Regulation VIN = 5V 20 mV ILOAD = 100 mA to800 mA 50/100 50/100 mV(max)(2) η Efficiency VIN = 5V,ILOAD = 800 mA 80 % DEVICE PARAMETERS IS InputSupplyCurrent VFEEDBACK = 14V (SwitchOff) 7.5 mA ISWITCH = 2.0A 25 mA VCOMP = 2.0V(Max DutyCycle) 50/85 50/85 mA(max) (1) Alllimitsensuredatroom temperature(standardtypeface)and attemperatureextremes(boldfacetype).Alllimitsareused tocalculate OutgoingQualityLevel,and are100% productiontested. (2) A militaryRETS electricaltestspecificationisavailableon request.Atthetimeofprinting,theLM1577K-12/883,LM1577K-15/883,and LM1577K-ADJ/883 RETS specificationscompliedfullywiththeboldfacelimitsinthesecolumns.The LM1577K-12/883,LM1577K- 15/883,and LM1577K-ADJ/883 may alsobe procuredtoStandardMilitaryDrawingspecifications. (3) Alllimitsensuredatroom temperature(standardtypeface)and attemperatureextremes(boldfacetype).Allroom temperaturelimitsare 100% productiontested.AlllimitsattemperatureextremesareensuredviacorrelationusingstandardStatisticalQualityControl(SQC) methods. (4) Externalcomponents such as thediode,inductor,inputand outputcapacitorscan affectswitchingregulatorperformance.When the LM1577/LM2577 isused as shown intheTestCircuit,systemperformancewillbe as specifiedby thesystemparameters. Copyright© 1999–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 3 ProductFolderLinks:LM1577 LM2577

LM1577,LM2577 SNOS658D –JUNE 1999–REVISED APRIL 2013 www.ti.com SpecificationswithstandardtypefaceareforTJ = 25°C, and thoseinbold typefaceapplyoverfullOperatingTemperature Range .Unlessotherwisespecified,VIN = 5V,and ISWITCH = 0. Symbol Parameter Conditions Typical LM1577-12 LM2577-12 Units Limit(1)(2) Limit(3) (Limits) VUV InputSupply ISWITCH = 100 mA 2.90 V UndervoltageLockout 2.70/2.65 2.70/2.65 V(min) fO OscillatorFrequency Measured atSwitchPin 52 kHz ISWITCH = 100 mA 48/42 48/42 kHz(min) 56/62 56/62 kHz(max) VREF OutputReference Measured atFeedback Pin V OutputReference VIN = 3.5Vto40V 7 mV VoltageLineRegulator R FB Feedback PinInput 9.7 kΩ Resistance G M ErrorAmp ICOMP = −30 μA to+30 μA 370 μmho Transconductance VCOMP = 1.0V 225/145 225/145 μmho(min) 515/615 515/615 μmho(max) AVOL ErrorAmp VCOMP = 1.1Vto1.9V 80 V/V VoltageGain R COMP = 1.0M Ω(5) 50/25 50/25 V/V(min) ErrorAmplifier Upper Limit 2.4 V Lower Limit 0.3 V ErrorAmplifier VFEEDBACK = 10.0Vto15.0V ±200 μA OutputCurrent VCOMP = 1.0V ±130/±90 ±130/±90 μA(min) ISS SoftStartCurrent VFEEDBACK = 10.0V 5.0 μA VCOMP = 0V 2.5/1.5 2.5/1.5 μA(min) D Maximum DutyCycle VCOMP = 1.5V 95 % ISWITCH = 100 mA 93/90 93/90 %(min) Switch 12.5 A/V Transconductance IL SwitchLeakage VSWITCH = 65V 10 μA Current VFEEDBACK = 15V (SwitchOff) 300/600 300/600 μA(max) VSAT SwitchSaturation ISWITCH = 2.0A 0.5 V NPN Switch 4.5 A CurrentLimit 3.7/3.0 3.7/3.0 A(min) (5) A 1.0M Ω resistorisconnectedtothecompensationpin(whichistheerroramplifier's output)toensureaccuracyinmeasuringAVOL .In actualapplications,thispin's loadresistanceshouldbe ≥10 M Ω,resultinginAVOL thatistypicallytwicetheensuredminimum limit.

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LM1577,LM2577 www.ti.com SNOS658D –JUNE 1999–REVISED APRIL 2013 SpecificationswithstandardtypefaceareforTJ = 25°C, and thoseinbold typefaceapplyoverfullOperatingTemperature Range .Unlessotherwisespecified,VIN = 5V,and ISWITCH = 0. Symbol Parameter Conditions Typical LM1577-15 LM2577-15 Units Limit(1)(2) Limit(3) (Limits) SYSTEM PARAMETERS CircuitofFigure30(4) VOUT OutputVoltage VIN = 5V to12V 15.0 V ILOAD = 100 mA to600 mA 14.50/14.25 14.50/14.25 V(min)(1) LineRegulation VIN = 3.5Vto12V 20 mV ILOAD = 300 mA mV(max)50/100 50/100 Load Regulation VIN = 5V 20 mV ILOAD = 100 mA to600 mA mV(max)50/100 50/100 η Efficiency VIN = 5V,ILOAD = 600 mA 80 % DEVICE PARAMETERS IS InputSupplyCurrent VFEEDBACK = 18.0V 7.5 mA (SwitchOff) 10.0/14.0 10.0/14.0 mA(max) ISWITCH = 2.0A 25 mA VCOMP = 2.0V 50/85 50/85 mA(max)(Max DutyCycle) VUV InputSupply ISWITCH = 100 mA 2.90 V Undervoltage 2.70/2.65 2.70/2.65 V(min)Lockout fO OscillatorFrequency Measured atSwitchPin 52 kHz ISWITCH = 100 mA 48/42 48/42 kHz(min) 56/62 56/62 kHz(max) VREF OutputReference Measured atFeedback Pin V OutputReference VIN = 3.5Vto40V 10 mV VoltageLineRegulation R FB Feedback PinInput 12.2 kΩ VoltageLineRegulator G M ErrorAmp ICOMP = −30 μA to+30 μA 300 μmho Transconductance VCOMP = 1.0V 170/110 170/110 μmho(min) 420/500 420/500 μmho(max) AVOL ErrorAmp VCOMP = 1.1Vto1.9V 65 V/V VoltageGain R COMP = 1.0M Ω(5) 40/20 40/20 V/V(min) (1) Alllimitsensuredatroom temperature(standardtypeface)and attemperatureextremes(boldfacetype).Alllimitsareused tocalculate OutgoingQualityLevel,and are100% productiontested. (2) A militaryRETS electricaltestspecificationisavailableon request.Atthetimeofprinting,theLM1577K-12/883,LM1577K-15/883,and LM1577K-ADJ/883 RETS specificationscompliedfullywiththeboldfacelimitsinthesecolumns.The LM1577K-12/883,LM1577K- 15/883,and LM1577K-ADJ/883 may alsobe procuredtoStandardMilitaryDrawingspecifications. (3) Alllimitsensuredatroom temperature(standardtypeface)and attemperatureextremes(boldfacetype).Allroom temperaturelimitsare 100% productiontested.AlllimitsattemperatureextremesareensuredviacorrelationusingstandardStatisticalQualityControl(SQC) methods. (4) Externalcomponents such as thediode,inductor,inputand outputcapacitorscan affectswitchingregulatorperformance.When the LM1577/LM2577 isused as shown intheTestCircuit,systemperformancewillbe as specifiedby thesystemparameters. (5) A 1.0M Ω resistorisconnectedtothecompensationpin(whichistheerroramplifier's output)toensureaccuracyinmeasuringAVOL .In actualapplications,thispin's loadresistanceshouldbe ≥10 M Ω,resultinginAVOL thatistypicallytwicetheensuredminimum limit. Copyright© 1999–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 5 ProductFolderLinks:LM1577 LM2577

LM1577,LM2577 SNOS658D –JUNE 1999–REVISED APRIL 2013 www.ti.com SpecificationswithstandardtypefaceareforTJ = 25°C, and thoseinbold typefaceapplyoverfullOperatingTemperature Range .Unlessotherwisespecified,VIN = 5V,and ISWITCH = 0. Symbol Parameter Conditions Typical LM1577-15 LM2577-15 Units Limit(1)(2) Limit(3) (Limits) ErrorAmplifier Upper Limit 2.4 V Lower Limit 0.3 V ErrorAmp VFEEDBACK = 12.0Vto18.0V ±200 μA OutputCurrent VCOMP = 1.0V ±130/±90 ±130/±90 μA(min) ISS SoftStartCurrent VFEEDBACK = 12.0V 5.0 μA VCOMP = 0V 2.5/1.5 2.5/1.5 μA(min) D Maximum Duty VCOMP = 1.5V 95 % Cycle ISWITCH = 100 mA 93/90 93/90 %(min) Switch 12.5 A/V Transconductance IL SwitchLeakage VSWITCH = 65V 10 μA Current VFEEDBACK = 18.0V 300/600 300/600 μA(max)(SwitchOff) VSAT SwitchSaturation ISWITCH = 2.0A 0.5 V Voltage VCOMP = 2.0V 0.7/0.9 0.7/0.9 V(max)(Max DutyCycle) NPN Switch VCOMP = 2.0V 4.3 A CurrentLimit 3.7/3.0 3.7/3.0 A(min)

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LM1577,LM2577 www.ti.com SNOS658D –JUNE 1999–REVISED APRIL 2013 SpecificationswithstandardtypefaceareforTJ = 25°C, and thoseinbold typefaceapplyoverfullOperatingTemperature Range .Unlessotherwisespecified,VIN = 5V,VFEEDBACK = VREF ,and ISWITCH = 0. Symbol Parameter Conditions Typical LM1577-ADJ LM2577-ADJ Units Limit(1)(2) Limit(3) (Limits) SYSTEM PARAMETERS CircuitofFigure31 (4) VOUT OutputVoltage VIN = 5V to10V 12.0 V ILOAD = 100 mA to800 mA (1) ΔVOUT /ΔVIN LineRegulation VIN = 3.5Vto10V 20 mV ILOAD = 300 mA 50/100 50/100 mV(max) ΔVOUT /ΔILOA Load Regulation VIN = 5V 20 mV D ILOAD = 100 mA to800 mA 50/100 50/100 mV(max) η Efficiency VIN = 5V,ILOAD = 800 mA 80 % DEVICE PARAMETERS IS InputSupplyCurrent VFEEDBACK = 1.5V(SwitchOff) 7.5 mA ISWITCH = 2.0A 25 mA VCOMP = 2.0V(Max DutyCycle) 50/85 50/85 mA(max) VUV InputSupply ISWITCH = 100 mA 2.90 V UndervoltageLockout 2.70/2.65 2.70/2.65 V(min) fO OscillatorFrequency Measured atSwitchPin 52 kHz ISWITCH = 100 mA 48/42 48/42 kHz(min) 56/62 56/62 kHz(max) VREF Reference Measured atFeedback Pin V ΔVREF /ΔVIN ReferenceVoltage VIN = 3.5Vto40V 0.5 mV LineRegulation IB ErrorAmp VCOMP = 1.0V 100 nA InputBiasCurrent 300/800 300/800 nA(max) G M ErrorAmp ICOMP = −30 μA to+30 μA 3700 μmho Transconductance VCOMP = 1.0V 2400/1600 2400/1600 μmho(min) 4800/5800 4800/5800 μmho(max) AVOL ErrorAmp VoltageGain VCOMP = 1.1Vto1.9V 800 V/V R COMP = 1.0M Ω(5) 500/250 500/250 V/V(min) ErrorAmplifier Upper Limit 2.4 V Lower Limit 0.3 V (1) Alllimitsensuredatroom temperature(standardtypeface)and attemperatureextremes(boldfacetype).Alllimitsareused tocalculate OutgoingQualityLevel,and are100% productiontested. (2) A militaryRETS electricaltestspecificationisavailableon request.Atthetimeofprinting,theLM1577K-12/883,LM1577K-15/883,and LM1577K-ADJ/883 RETS specificationscompliedfullywiththeboldfacelimitsinthesecolumns.The LM1577K-12/883,LM1577K- 15/883,and LM1577K-ADJ/883 may alsobe procuredtoStandardMilitaryDrawingspecifications. (3) Alllimitsensuredatroom temperature(standardtypeface)and attemperatureextremes(boldfacetype).Allroom temperaturelimitsare 100% productiontested.AlllimitsattemperatureextremesareensuredviacorrelationusingstandardStatisticalQualityControl(SQC) methods. (4) Externalcomponents such as thediode,inductor,inputand outputcapacitorscan affectswitchingregulatorperformance.When the LM1577/LM2577 isused as shown intheTestCircuit,systemperformancewillbe as specifiedby thesystemparameters. (5) A 1.0M Ω resistorisconnectedtothecompensationpin(whichistheerroramplifier's output)toensureaccuracyinmeasuringAVOL .In actualapplications,thispin's loadresistanceshouldbe ≥10 M Ω,resultinginAVOL thatistypicallytwicetheensuredminimum limit. Copyright© 1999–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 7 ProductFolderLinks:LM1577 LM2577

LM1577,LM2577 SNOS658D –JUNE 1999–REVISED APRIL 2013 www.ti.com SpecificationswithstandardtypefaceareforTJ = 25°C, and thoseinbold typefaceapplyoverfullOperatingTemperature Range .Unlessotherwisespecified,VIN = 5V,VFEEDBACK = VREF ,and ISWITCH = 0. Symbol Parameter Conditions Typical LM1577-ADJ LM2577-ADJ Units Limit(1)(2) Limit(3) (Limits) ErrorAmp VFEEDBACK = 1.0Vto1.5V ±200 μA OutputCurrent VCOMP = 1.0V ±130/±90 ±130/±90 μA(min) ISS SoftStartCurrent VFEEDBACK = 1.0V 5.0 μA VCOMP = 0V 2.5/1.5 2.5/1.5 μA(min) D Maximum DutyCycle VCOMP = 1.5V 95 % ISWITCH = 100 mA 93/90 93/90 %(min) ΔISWITCH /ΔVC Switch 12.5 A/V OMP Transconductance IL SwitchLeakage VSWITCH = 65V 10 μA Current VFEEDBACK = 1.5V(SwitchOff) 300/600 300/600 μA(max) VSAT SwitchSaturation ISWITCH = 2.0A 0.5 V NPN Switch VCOMP = 2.0V 4.3 A CurrentLimit 3.7/3.0 3.7/3.0 A(min) THERMAL PARAMETERS (AllVersions) θJA ThermalResistance K Package,JunctiontoAmbient 35 θJC K Package,JunctiontoCase 1.5 θJA T Package,JunctiontoAmbient 65 θJC T Package,JunctiontoCase 2 °C/W θJA N Package,JunctiontoAmbient (6) 85 θJA M Package,JunctiontoAmbient (6) 100 θJA S Package,JunctiontoAmbient (7) 37 (6) Junctiontoambientthermalresistancewithapproximately1 squareinchofpc boardcoppersurroundingtheleads.Additionalcopper areawilllowerthermalresistancefurther.See thermalmodel in“SwitchersMade Simple”software. (7) IftheDDPAK/TO-263 package isused,thethermalresistancecan be reducedby increasingthePC boardcopperareathermally connectedtothepackage.Using0.5squareinchesofcopperarea,θJA is50°C/W; with1 squareinchofcopperarea,θJA is37°C/W; and with1.6ormore squareinchesofcopperarea,θJA is32°C/W.

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LM1577,LM2577 www.ti.com SNOS658D –JUNE 1999–REVISED APRIL 2013 TypicalPerformance Characteristics ReferenceVoltage ReferenceVoltage vs Temperature vs Temperature Figure8. Figure9. ReferenceVoltage Δ ReferenceVoltage vs Temperature vs Supply Voltage Figure10. Figure11. Δ ReferenceVoltage Δ ReferenceVoltage vs Supply Voltage vs Supply Voltage Figure12. Figure13. Copyright© 1999–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 9 ProductFolderLinks:LM1577 LM2577

LM1577,LM2577 SNOS658D –JUNE 1999–REVISED APRIL 2013 www.ti.com TypicalPerformance Characteristics(continued) ErrorAmp Transconductance ErrorAmp Transconductance vs Temperature vs Temperature Figure14. Figure15. ErrorAmp Voltage Gain ErrorAmp Transconductance vs vs Temperature Temperature Figure16. Figure17. ErrorAmp Voltage ErrorAmp Voltage Gain Gain vs vs Temperature Temperature Figure18. Figure19.

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LM1577,LM2577 www.ti.com SNOS658D –JUNE 1999–REVISED APRIL 2013 TypicalPerformance Characteristics(continued) QuiescentCurrent QuiescentCurrent vs Temperature vs Switch Current Figure20. Figure21. CurrentLimitResponse Time CurrentLimit vs vs Temperature Overdrive Figure22. Figure23. Switch SaturationVoltage Switch Transconductance vs Switch Current vs Temperature Figure24. Figure25. Copyright© 1999–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 11 ProductFolderLinks:LM1577 LM2577

LM1577,LM2577 SNOS658D –JUNE 1999–REVISED APRIL 2013 www.ti.com TypicalPerformance Characteristics(continued) Feedback Pin Bias Current vs OscillatorFrequency Temperature vs Temperature Figure26. Figure27. Maximum Power Dissipation (DDPAK/TO-263) (1) Figure28. (1) IftheDDPAK/TO-263 package isused,thethermalresistancecan be reducedby increasingthePC boardcopperareathermally connectedtothepackage.Using0.5squareinchesofcopperarea,θJA is50°C/W; with1 squareinchofcopperarea,θJA is37°C/W; and with1.6ormore squareinchesofcopperarea,θJA is32°C/W.

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LM1577,LM2577 www.ti.com SNOS658D –JUNE 1999–REVISED APRIL 2013 LM1577-12,LM2577-12 TEST CIRCUIT L = 415-0930(AIE) D = any manufacturer C OUT = Sprague Type 673D Electrolytic680 μF,20V Note:Pinnumbers shown areforTO-220 (T)package Figure29. CircuitUsed toSpecifySystem Parameters for12V Versions LM1577-15,LM2577-15 TestCircuit L = 415-0930(AIE) D = any manufacturer C OUT = Sprague Type 673D Electrolytic680 μF,20V Note:Pinnumbers shown areforTO-220 (T)package Figure30. CircuitUsed toSpecifySystem Parameters for15V Versions Copyright© 1999–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 13 ProductFolderLinks:LM1577 LM2577

LM1577,LM2577 SNOS658D –JUNE 1999–REVISED APRIL 2013 www.ti.com LM1577-ADJ, LM2577-ADJ TestCircuit L = 415-0930(AIE) D = any manufacturer C OUT = Sprague Type 673D Electrolytic680 μF,20V R1 = 48.7kinserieswith511Ω (1%) R2 = 5.62k(1%) Note:Pinnumbers shown areforTO-220 (T)package Figure31. CircuitUsed toSpecifySystem Parameters forADJ Versions ApplicationHints Note:Pinnumbers shown areforTO-220 (T)package *ResistorsareinternaltoLM1577/LM2577 for12V and 15V versions. Figure32. LM1577/LM2577 Block Diagram and Boost RegulatorApplication

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LM1577,LM2577 www.ti.com SNOS658D –JUNE 1999–REVISED APRIL 2013 STEP-UP (BOOST) REGULATOR Figure32 shows theLM1577-ADJ/LM2577-ADJ used as a Step-UpRegulator.Thisisa switchingregulatorused forproducingan outputvoltagegreaterthantheinputsupplyvoltage.The LM1577-12/LM2577-12 and LM1577- 15/LM2577-15 can alsobe used forstep-upregulatorswith12V or 15V outputs(respectively),by tyingthe feedbackpindirectlytotheregulatoroutput. A basicexplanationofhow itworks isas follows.The LM1577/LM2577 turnsitsoutputswitchon and offata frequencyof52 kHz, and thiscreatesenergyintheinductor(L).When theNPN switchturnson,theinductor currentchargesup ata rateofVIN/L,storingcurrentintheinductor.When theswitchturnsoff,thelowerend of theinductorfliesabove VIN,dischargingitscurrentthroughdiode(D)intotheoutputcapacitor(COUT )ata rateof (VOUT − VIN)/L.Thus,energystoredintheinductorduringtheswitchon timeistransferredtotheoutputduring the switchofftime.The outputvoltageiscontrolledby the amount of energy transferredwhich,in turn,is controlledby modulatingthepeak inductorcurrent.Thisisdone by feedingback a portionoftheoutputvoltage totheerroramp, whichamplifiesthedifferencebetween thefeedbackvoltageand a 1.230V reference.The error amp outputvoltageiscompared toa voltageproportionaltotheswitchcurrent(i.e.,inductorcurrentduringthe switchon time). The comparatorterminatesthe switchon timewhen the two voltagesare equal,therebycontrollingthe peak switchcurrenttomaintaina constantoutputvoltage. Voltageand currentwaveforms forthiscircuitare shown inFigure33, and formulasforcalculatingthem are giveninTable1. Figure33. Step-Up RegulatorWaveforms Table1.Step-Up RegulatorFormulas(1) DutyCycle D AverageInductorCurrent IIND(AVE) InductorCurrentRipple ΔIIND Peak InductorCurrent IIND(PK) Peak SwitchCurrent ISW(PK) SwitchVoltageWhen Off VSW(OFF) VOUT + VF DiodeReverseVoltage VR VOUT − VSAT AverageDiodeCurrent ID(AVE) ILOAD Peak DiodeCurrent ID(PK) Power DissipationofLM1577/2577 PD (1) VF = ForwardBiasedDiodeVoltage ILOAD = OutputLoad Current Copyright© 1999–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 15 ProductFolderLinks:LM1577 LM2577

LM1577,LM2577 SNOS658D –JUNE 1999–REVISED APRIL 2013 www.ti.com STEP-UP REGULATOR DESIGN PROCEDURE The followingdesignprocedurecan be used to selectthe appropriateexternalcomponents forthe circuitin Figure32,based on thesesystemrequirements. Given:

• VIN (min)= Minimum inputsupplyvoltage
• VOUT = Regulatedoutputvoltage
• ILOAD(max) = Maximum outputloadcurrent
• Before proceedingany further,determineifthe LM1577/LM2577 can providethese valuesof VOUT and ILOAD(max) when operatingwiththeminimum valueofVIN.The upperlimitsforVOUT and ILOAD(max) aregivenby thefollowingequations. where
• VOUT ≤ 60V
• VOUT ≤ 10 × VIN(min) (3) These limitsmust be greaterthanorequaltothevaluesspecifiedinthisapplication. 1. InductorSelection(L) A.VoltageOptions: 1.For 12V or 15V output From Figure34 (for12V output)or Figure35 (for15V output),identifyinductorcode forregion indicatedby VIN (min)and ILOAD (max).The shaded regionindicatesconditionsforwhichtheLM1577/LM2577 outputswitchwouldbe operatingbeyond itsswitchcurrentrating.The minimum operatingvoltageforthe LM1577/LM2577 is3.5V. From here,proceed tostepC . 2.For Adjustableversion Preliminarycalculations: The inductorselectionisbased on thecalculationofthefollowingthreeparameters: D (max),themaximum switchdutycycle(0≤ D ≤ 0.9): (4) where VF = 0.5VforSchottkydiodesand 0.8Vforfastrecoverydiodes(typically); E •T,theproductofvolts× timethatchargestheinductor: (5) IIND,DC,theaverageinductorcurrentunderfullload; (6) B. IdentifyInductorValue: 1.From Figure36,identifytheinductorcode fortheregionindicatedby theintersectionofE•T and IIND,DC. Thiscode givestheinductorvalueinmicrohenries.The L orH prefixsignifieswhethertheinductorisrated fora maximum E•T of90 V•μs (L)or250 V•μs (H). 2.IfD < 0.85,go on tostepC. IfD ≥ 0.85,thencalculatetheminimum inductanceneeded toensurethe switchingregulator'sstability: (7) IfLMIN issmallerthantheinductorvaluefoundinstepB1,go on tostepC. Otherwise,theinductorvaluefoundin stepB1 istoolow;an appropriateinductorcode shouldbe obtainedfromthegraphas follows: 1.FindthelowestvalueinductorthatisgreaterthanLMIN .

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LM1577,LM2577 www.ti.com SNOS658D –JUNE 1999–REVISED APRIL 2013 2.Findwhere E•T intersectsthisinductorvaluetodetermineifithas an L orH prefix.IfE•T intersectsboththeL and H regions,selecttheinductorwithan H prefix. Figure34. LM2577-12 InductorSelectionGuide Figure35. LM2577-15 InductorSelectionGuide Copyright© 1999–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 17 ProductFolderLinks:LM1577 LM2577

LM1577,LM2577 SNOS658D –JUNE 1999–REVISED APRIL 2013 www.ti.com Note:These chartsassume thattheinductorripplecurrentisapproximately20% to30% oftheaverageinductor current(when theregulatorisunderfullload).Greaterripplecurrentcauseshigherpeak switchcurrentsand greater outputripplevoltage;lowerripplecurrentisachievedwithlarger-valueinductors.The factorof20 to30% ischosen as a convenientbalancebetween thetwo extremes. Figure36. LM1577-ADJ/LM2577-ADJ InductorSelectionGraph C. Selectan inductorfromTable2 whichcross-referencestheinductorcodes tothepartnumbers ofthree differentmanufacturers.Completespecificationsfortheseinductorsareavailablefromtherespective manufacturers.The inductorslistedinthistablehave thefollowingcharacteristics:

• AIE:ferrite,pot-coreinductors;Benefitsofthistypearelow electro-magneticinterference(EMI),small physicalsize,and verylow power dissipation(coreloss).Be carefulnottooperatetheseinductorstoo farbeyond theirmaximum ratingsforE•T and peak current,as thiswillsaturatethecore.
• Pulse:powdered iron,toroidcoreinductors;BenefitsarelowEMI and abilitytowithstandE•T and peak currentabove ratedvaluebetterthanferritecores.
• Renco: ferrite,bobbin-coreinductors;Benefitsarelow costand bestabilitytowithstandE•T and peak currentabove ratedvalue.Be aware thattheseinductorsgeneratemore EMI thantheothertypes,and thismay interferewithsignalssensitivetonoise.

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LM1577,LM2577 www.ti.com SNOS658D –JUNE 1999–REVISED APRIL 2013 Table2.TableofStandardizedInductorsand Manufacturer's PartNumbers (1) Inductor Manufacturer'sPartNumber Code Schott Pulse Renco L47 67126980 PE -53112 RL2442 L68 67126990 PE -92114 RL2443 L100 67127000 PE -92108 RL2444 L150 67127010 PE -53113 RL1954 L220 67127020 PE -52626 RL1953 L330 67127030 PE -52627 RL1952 L470 67127040 PE -53114 RL1951 L680 67127050 PE -52629 RL1950 H150 67127060 PE -53115 RL2445 H220 67127070 PE -53116 RL2446 H330 67127080 PE -53117 RL2447 H470 67127090 PE -53118 RL1961 H680 67127100 PE -53119 RL1960 H1000 67127110 PE -53120 RL1959 H1500 67127120 PE -53121 RL1958 H2200 67127130 PE -53122 RL2448 (1) SchottCorp.,(612)475-1173 1000 ParkersLake Rd.,Wayzata,MN 55391 Pulse Engineering,(619)268-2400 P.O.Box 12235,San Diego,CA 92112 Renco ElectronicsInc.,(516)586-5566 60 JeffrynBlvd.East,Deer Park,NY 11729 2.Compensation Network (RC ,C C )and Output Capacitor(COUT )Selection R C and C C form a pole-zerocompensationnetworkthatstabilizestheregulator.The valuesofR C and C C are mainlydependanton theregulatorvoltagegain,ILOAD(max) ,L and C OUT .The followingprocedurecalculatesvalues forR C ,C C ,and C OUT thatensureregulatorstability.Be aware thatthisproceduredoesn'tnecessarilyresultinR C and C C thatprovideoptimum compensation.In orderto ensure optimum compensation,one of the standard proceduresfortestingloopstabilitymust be used,such as measuringVOUT transientresponsewhen pulsing ILOAD (seeFigure39). A.First,calculatethemaximum valueforR C . (8) Selecta resistorlessthanorequaltothisvalue,and itshouldalsobe no greaterthan3 kΩ. B.Calculatetheminimum valueforC OUT usingthefollowingtwo equations. (9) The largerofthesetwo valuesistheminimum valuethatensuresstability. C. Calculatetheminimum valueofC C . (10) Copyright© 1999–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 19 ProductFolderLinks:LM1577 LM2577

LM1577,LM2577 SNOS658D –JUNE 1999–REVISED APRIL 2013 www.ti.com The compensationcapacitorisalsopartofthesoftstartcircuitry.When power totheregulatoristurnedon,the switchdutycycleisallowedto riseat a ratecontrolledby thiscapacitor(withno controlon the dutycycle,it would immediatelyriseto90%, drawinghuge currentsfromtheinputpower supply).Inordertooperateproperly, thesoftstartcircuitrequiresC C ≥ 0.22μF. The valueof the outputfiltercapacitorisnormallylargeenough to requirethe use of aluminum electrolytic capacitors.Table3 listsseveraldifferenttypesthatarerecommended forswitchingregulators,and thefollowing parametersareused toselectthepropercapacitor. Working Voltage(WVDC): Choose a capacitorwitha workingvoltageat least20% higherthan the regulator outputvoltage. RippleCurrent:Thisisthe maximum RMS valueof currentthatchargesthe capacitorduringeach switching cycle.Forstep-upand flybackregulators,theformulaforripplecurrentis (11) Choose a capacitorthatisratedatleast50% higherthanthisvalueat52 kHz. EquivalentSeriesResistance(ESR) :Thisistheprimarycause ofoutputripplevoltage,and italsoaffectsthe valuesofR C and C C needed tostabilizetheregulator.As a result,theprecedingcalculationsforC C and R C are onlyvalidifESR doesn'texceed themaximum valuespecifiedby thefollowingequations. (12) Selecta capacitorwithESR, at52 kHz,thatislessthanorequaltothelowervaluecalculated.Most electrolytic capacitorsspecifyESR at 120 Hz which is15% to 30% higherthan at 52 kHz. Also,be aware thatESR increasesby a factorof2 when operatingat−20°C. Ingeneral,low valuesofESR are achievedby usinglargevaluecapacitors(C ≥ 470 μF),and capacitorswith highWVDC, orby parallelingsmaller-valuecapacitors. 3.Output VoltageSelection(R1 and R2) ThissectionisforapplicationsusingtheLM1577-ADJ/LM2577-ADJ. SkipthissectioniftheLM1577-12/LM2577- 12 orLM1577-15/LM2577-15isbeingused. WiththeLM1577-ADJ/LM2577-ADJ, theoutputvoltageisgivenby VOUT = 1.23V(1+ R1/R2) (13) ResistorsR1 and R2 dividetheoutputdown so itcan be compared withtheLM1577-ADJ/LM2577-ADJ internal 1.23Vreference.Fora givendesiredoutputvoltageVOUT ,selectR1 and R2 so that (14) 4.InputCapacitorSelection(CIN) The switchingactioninthe step-upregulatorcauses a triangularripplecurrentto be drawn from the supply source.Thisinturncauses noisetoappearon thesupplyvoltage.For properoperationoftheLM1577, theinput voltageshouldbe decoupled.BypassingtheInputVoltagepindirectlytoground witha good quality,low ESR, 0.1μF capacitor(leadsas shortas possible)isnormallysufficient.

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LM1577,LM2577 www.ti.com SNOS658D –JUNE 1999–REVISED APRIL 2013 Table3.Aluminum ElectrolyticCapacitors Recommended forSwitchingRegulators CornellDublier— Types 239,250,251,UFT, 300,or350 P.O.Box 128,Pickens,SC 29671 (803)878-6311 Nichicon— Types PF, PX, orPZ

927 EastParkway,

Schaumburg,IL60173 (708)843-7500 Sprague — Types 672D, 673D, or674D Box 1,Sprague Road, Lansing,NC 28643 (919)384-2551 UnitedChemi-Con — Types LX,SXF, orSXJ

9801 West HigginsRoad,

Rosemont,IL60018 (708)696-2000 IftheLM1577 islocatedfarfromthesupplysourcefiltercapacitors,an additionallargeelectrolyticcapacitor(e.g. 47 μF)isoftenrequired. 5.Diode Selection(D) The switchingdiodeused inthe boostregulatormust withstanda reversevoltageequalto the circuitoutput voltage,and must conductthe peak outputcurrentof the LM2577. A suitablediode must have a minimum reversebreakdown voltagegreaterthan the circuitoutputvoltage,and shouldbe ratedforaverage and peak currentgreaterthanILOAD(max) and ID(PK).Schottkybarrierdiodesareoftenfavoredforuse inswitchingregulators. Theirlow forwardvoltagedrop allowshigherregulatorefficiencythanifa (lessexpensive)fastrecoverydiode was used.See Table4 forrecommended partnumbers and voltageratingsof1A and 3A diodes. Table4.Diode SelectionChart VOUT Schottky FastRecovery (max) 1A 3A 1A 3A 20V 1N5817 1N5820 MBR120P MBR320P 1N5818 1N5821 30V MBR130P MBR330P 11DQ03 31DQ03 1N5819 1N5822 40V MBR140P MBR340P 11DQ04 31DQ04 MBR150 MBR350 1N4933 50V 11DQ05 31DQ05 MUR105 1N4934 MR851 100V HER102 30DL1 MUR110 MR831 10DL1 HER302 BOOST REGULATOR CIRCUIT EXAMPLE By addinga few externalcomponents (asshown inFigure37),theLM2577 can be used toproducea regulated outputvoltagethatisgreaterthantheappliedinputvoltage.Typicalperformanceofthisregulatorisshown in Figure38 and Figure39. The switchingwaveforms observedduringthe operationof thiscircuitare shown in Figure40. Copyright© 1999–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 21 ProductFolderLinks:LM1577 LM2577

LM1577,LM2577 SNOS658D –JUNE 1999–REVISED APRIL 2013 www.ti.com Note:Pinnumbers shown areforTO-220 (T)package. Figure37. Step-upRegulatorDelivers12V from a 5V Input Figure38. LineRegulation(Typical)ofStep-Up RegulatorofFigure37 A:OutputVoltageChange, 100 mV/div.(AC-coupled) B:Load current,0.2A/div Horizontal:5 ms/div Figure39. Load TransientResponse ofStep-Up RegulatorofFigure37

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LM1577,LM2577 www.ti.com SNOS658D –JUNE 1999–REVISED APRIL 2013 A:Switchpinvoltage,10 V/div B:Switchpincurrent,2 A/div C: Inductorcurrent,2 A/div D: Outputripplevoltage,100 mV/div(AC-coupled) Horizontal:5 μs/div Figure40. SwitchingWaveforms ofStep-Up RegulatorofFigure37 FLYBACK REGULATOR A Flybackregulatorcan producesingleormultipleoutputvoltagesthatarelowerorgreaterthantheinputsupply voltage.Figure42 shows theLM1577/LM2577 used as a flybackregulatorwithpositiveand negativeregulated outputs.Itsoperationissimilartoa step-upregulator,excepttheoutputswitchcontolstheprimarycurrentofa flybacktransformer.Note thattheprimaryand secondarywindingsareoutofphase,so no currentflowsthrough secondarywhen currentflowsthroughthe primary.Thisallowsthe primaryto charge up the transformercore when theswitchison.When theswitchturnsoff,thecoredischargesby sendingcurrentthroughthesecondary, and thisproduces voltageat the outputs.The outputvoltagesare controlledby adjustingthe peak primary current,as describedintheSTEP-UP (BOOST) REGULATOR section. Voltageand currentwaveforms forthiscircuitare shown inFigure41, and formulasforcalculatingthem are giveninTable5. FLYBACK REGULATOR DESIGN PROCEDURE 1.TransformerSelection A familyofstandardizedflybacktransformersisavailableforcreatingflybackregulatorsthatproducedualoutput voltages,from ±10V to ±15V, as shown inFigure42. Table 6 liststhesetransformerswiththe inputvoltage, outputvoltagesand maximum loadcurrenttheyaredesignedfor. 2.Compensation Network (CC ,R C )and Output Capacitor(COUT )Selection As explainedintheStep-Up RegulatorDesign Procedure,C C ,R C and C OUT must be selectedas a group.The followingprocedureisfora dualoutputflybackregulatorwithequalturnsratiosforeach secondary(i.e.,both outputvoltageshave thesame magnitude).The equationscan be used fora singleoutputregulatorby changing ∑ILOAD(max) toILOAD(max) inthefollowingequations. A.First,calculatethemaximum valueforR C . Copyright© 1999–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 23 ProductFolderLinks:LM1577 LM2577

LM1577,LM2577 SNOS658D –JUNE 1999–REVISED APRIL 2013 www.ti.com (15) Where ∑ILOAD(max) isthesum oftheloadcurrent(magnitude)requiredfrom bothoutputs.Selecta resistorless thanorequaltothisvalue,and no greaterthan3 kΩ. B.Calculatetheminimum valuefor∑C OUT (sum ofC OUT atbothoutputs)usingthefollowingtwo equations. (16) The largerofthesetwo valuesmust be used toensureregulatorstability. Figure41. FlybackRegulatorWaveforms T1 = PulseEngineering,PE-65300 D1, D2 = 1N5821 Figure42. LM1577-ADJ/LM2577-ADJ FlybackRegulatorwith± Outputs Table5.FlybackRegulatorFormulas DutyCycle D (17) PrimaryCurrentVariation ΔIP (18)

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LM1577,LM2577 www.ti.com SNOS658D –JUNE 1999–REVISED APRIL 2013 Table5.FlybackRegulatorFormulas (continued) Peak PrimaryCurrent IP(PK) (19) SwitchVoltagewhen Off VSW(OFF) (20) DiodeReverseVoltage VR VOUT + N (VIN− VSAT ) AverageDiodeCurrent ID(AVE) ILOAD Peak DiodeCurrent ID(PK) (21) ShortCircuitDiodeCurrent (22) Power DissipationofLM1577/LM2577 PD (23) C. Calculatetheminimum valueofC C (24) D. Calculatethemaximum ESR ofthe+VOUT and −VOUT outputcapacitorsinparallel. (25) Thisformulacan alsobe used tocalculatethemaximum ESR ofa singleoutputregulator. At thispoint,refertothissame sectionintheSTEP-UP REGULATOR DESIGN PROCEDURE sectionformore informationregardingtheselectionofC OUT . 3.Output VoltageSelection ThissectionisforapplicationsusingtheLM1577-ADJ/LM2577-ADJ. SkipthissectioniftheLM1577-12/LM2577- 12 orLM1577-15/LM2577-15isbeingused. WiththeLM1577-ADJ/LM2577-ADJ, theoutputvoltageisgivenby VOUT = 1.23V(1+ R1/R2) (26) ResistorsR1 and R2 dividetheoutputvoltagedown so itcan be compared withtheLM1577-ADJ/LM2577-ADJ internal1.23Vreference.Fora desiredoutputvoltageVOUT ,selectR1 and R2 so that (27) 4.Diode Selection The switchingdiode in a flybackconvertermust withstandthe reversevoltagespecifiedby the following equation. (28) A suitablediodemust have a reversevoltageratinggreaterthanthis.Inadditionitmust be ratedformore than theaverageand peak diodecurrentslistedinTable5. 5.InputCapacitorSelection Copyright© 1999–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 25 ProductFolderLinks:LM1577 LM2577

LM1577,LM2577 SNOS658D –JUNE 1999–REVISED APRIL 2013 www.ti.com The primaryofa flybacktransformerdraws discontinuouspulsesofcurrentfromtheinputsupply.As a result,a flybackregulatorgeneratesmore noiseattheinputsupplythana step-upregulator,and thisrequiresa larger bypass capacitortodecoupletheLM1577/LM2577 VIN pinfromthisnoise.For most applications,a low ESR, 1.0 μF cap willbe sufficient,ifitisconnectedveryclosetotheVIN and Ground pins. Transformer Input Dual Maximum Type Voltage Output Output Voltage Current LP = 100 μH 5V ±10V 325 mA

1 N = 1 5V ±12V 275 mA

5V ±15V 225 mA 10V ±10V 700 mA 10V ±12V 575 mA

2 LP = 200 μH 10V ±15V 500 mA

N = 0.5 12V ±10V 800 mA 12V ±12V 700 mA 12V ±15V 575 mA

3 LP = 250 μH 15V ±10V 900 mA

N = 0.5 15V ±12V 825 mA 15V ±15V 700 mA Table6.FlybackTransformerSelectionGuide Transformer Manufacturers'PartNumbers Type AIE Pulse Renco 1 326-0637 PE-65300 RL-2580 2 330-0202 PE-65301 RL-2581 3 330-0203 PE-65302 RL-2582 In additionto thisbypass cap, a largercapacitor(≥ 47 μF) shouldbe used where the flybacktransformer connectstotheinputsupply.Thiswillattenuatenoisewhich may interferewithothercircuitsconnectedtothe same inputsupplyvoltage. 6.Snubber Circuit A “snubber”circuitisrequiredwhen operatingfrominputvoltagesgreaterthan10V, orwhen usinga transformer withLP ≥ 200 μH. Thiscircuitclamps a voltagespikefromthetransformerprimarythatoccursimmediatelyafter the outputswitchturnsoff.Withoutit,the switchvoltagemay exceed the 65V maximum rating.As shown in Figure43, the snubber consistsof a fastrecoverydiode,and a parallelRC. The RC valuesare selectedfor switchclamp voltage(VCLAMP )thatis5V to10V greaterthanVSW(OFF) .Use thefollowingequationstocalculateR and C; (29) Power dissipation(andpower rating)oftheresistoris; (30) The fastrecoverydiodemust have a reversevoltageratinggreaterthanVCLAMP .

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LM1577,LM2577 www.ti.com SNOS658D –JUNE 1999–REVISED APRIL 2013 Figure43. Snubber Circuit FLYBACK REGULATOR CIRCUIT EXAMPLE The circuitofFigure44 produces±15V (at225 mA each)from a single5V input.The outputregulationofthis circuitisshown in Figure45 and Figure47, whilethe load transientresponse isshown in Figure46 and Figure48.Switchingwaveformsseen inthiscircuitareshown inFigure49. T1 = PulseEngineering,PE-65300 D1, D2 = 1N5821 Figure44. FlybackRegulatorEasilyProvidesDual Outputs Figure45. LineRegulation(Typical)ofFlyback RegulatorofFigure44,+15V Output Copyright© 1999–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 27 ProductFolderLinks:LM1577 LM2577

LM1577,LM2577 SNOS658D –JUNE 1999–REVISED APRIL 2013 www.ti.com A:OutputVoltageChange, 100 mV/div B:OutputCurrent,100 mA/div Horizontal:10 ms/div Figure46. Load TransientResponse ofFlyback RegulatorofFigure44,+15V Output Figure47. LineRegulation(Typical)ofFlyback RegulatorofFigure44,−15V Output

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LM1577,LM2577 www.ti.com SNOS658D –JUNE 1999–REVISED APRIL 2013 A:OutputVoltageChange, 100 mV/div B:OutputCurrent,100 mA/div Horizontal:10 ms/div Figure48. Load TransientResponse ofFlyback RegulatorofFigure44,−15V Output A:Switchpinvoltage,20 V/div B:Primarycurrent,2 A/div C: +15V Secondarycurrent,1 A/div D: +15V Outputripplevoltage,100 mV/div Horizontal:5 μs/div Figure49. SwitchingWaveforms ofFlybackRegulatorofFigure44,Each Output Loaded with60Ω Copyright© 1999–2013,Texas InstrumentsIncorporated SubmitDocumentationFeedback 29 ProductFolderLinks:LM1577 LM2577

LM1577,LM2577 SNOS658D –JUNE 1999–REVISED APRIL 2013 www.ti.com

REVISION HISTORY

Changes from RevisionC (April2013)toRevisionD Page

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www.ti.com 11-Apr-2013 Addendum-Page 1 PACKAGING INFORMATION Orderable Device Status (1) Package Type Package Drawing Pins Package Qty Eco Plan (2) Lead/Ball Finish MSL Peak Temp (3) Op Temp (°C) Top-Side Markings (4) Samples LM2577M-ADJ ACTIVE SOIC DW 24 30 TBD Call TI Call TI -40 to 125 LM2577M -ADJ P+ LM2577M-ADJ/NOPB ACTIVE SOIC DW 24 30 Green (RoHS & no Sb/Br) CU SN Level-3-260C-168 HR -40 to 125 LM2577M -ADJ P+ LM2577N-ADJ ACTIVE PDIP NBG 16 20 TBD Call TI Call TI -40 to 125 LM2577N-ADJ LM2577N-ADJ/NOPB ACTIVE PDIP NBG 16 20 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM -40 to 125 LM2577N-ADJ LM2577S-12 ACTIVE DDPAK/ TO-263 KTT 5 45 TBD Call TI Call TI -40 to 125 LM2577S -12 P+ LM2577S-12/NOPB ACTIVE DDPAK/ TO-263 KTT 5 45 Pb-Free (RoHS Exempt) CU SN Level-3-245C-168 HR -40 to 125 LM2577S -12 P+ LM2577S-ADJ ACTIVE DDPAK/ TO-263 KTT 5 45 TBD Call TI Call TI -40 to 125 LM2577S -ADJ P+ LM2577S-ADJ/NOPB ACTIVE DDPAK/ TO-263 KTT 5 45 Pb-Free (RoHS Exempt) CU SN Level-3-245C-168 HR -40 to 125 LM2577S -ADJ P+ LM2577SX-12 ACTIVE DDPAK/ TO-263 KTT 5 500 TBD Call TI Call TI -40 to 125 LM2577S -12 P+ LM2577SX-12/NOPB ACTIVE DDPAK/ TO-263 KTT 5 500 Pb-Free (RoHS Exempt) CU SN Level-3-245C-168 HR -40 to 125 LM2577S -12 P+ LM2577SX-ADJ ACTIVE DDPAK/ TO-263 KTT 5 500 TBD Call TI Call TI -40 to 125 LM2577S -ADJ P+ LM2577SX-ADJ/NOPB ACTIVE DDPAK/ TO-263 KTT 5 500 Pb-Free (RoHS Exempt) CU SN Level-3-245C-168 HR -40 to 125 LM2577S -ADJ P+ LM2577T-12 ACTIVE TO-220 KC 5 45 TBD Call TI Call TI -40 to 125 LM2577T-12 LM2577T-12/LB03 ACTIVE TO-220 NDH 5 45 TBD Call TI Call TI LM2577T-12 LM2577T-12/LF03 ACTIVE TO-220 NDH 5 45 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM LM2577T-12 LM2577T-12/NOPB ACTIVE TO-220 KC 5 45 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM -40 to 125 LM2577T-12 LM2577T-15 ACTIVE TO-220 KC 5 45 TBD Call TI Call TI -40 to 125 LM2577T-15

www.ti.com 11-Apr-2013 Addendum-Page 2 Orderable Device Status (1) Package Type Package Drawing Pins Package Qty Eco Plan (2) Lead/Ball Finish MSL Peak Temp (3) Op Temp (°C) Top-Side Markings (4) Samples LM2577T-15/LB03 ACTIVE TO-220 NDH 5 45 TBD Call TI Call TI LM2577T-15 LM2577T-15/NOPB ACTIVE TO-220 KC 5 45 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM -40 to 125 LM2577T-15 LM2577T-ADJ ACTIVE TO-220 KC 5 45 TBD Call TI Call TI -40 to 125 LM2577T -ADJ LM2577T-ADJ/LB02 ACTIVE TO-220 NEB 5 45 TBD Call TI Call TI LM2577T -ADJ LM2577T-ADJ/LB03 ACTIVE TO-220 NDH 5 45 TBD Call TI Call TI LM2577T -ADJ LM2577T-ADJ/LF03 ACTIVE TO-220 NDH 5 45 Green (RoHS & no Sb/Br) CU SN Level-1-NA-UNLIM LM2577T -ADJ LM2577T-ADJ/NOPB ACTIVE TO-220 KC 5 45 Pb-Free (RoHS Exempt) CU SN Level-1-NA-UNLIM -40 to 125 LM2577T -ADJ (1) The marketing status values are defined as follows: ACTIVE: Product device recommended for new designs. LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect. NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design. PREVIEW: Device has been announced but is not in production. Samples may or may not be available. OBSOLETE: TI has discontinued the production of the device. (2) Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check http://www.ti.com/productcontent for the latest availability information and additional product content details. TBD: The Pb-Free/Green conversion plan has not been defined. Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes. Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and package, or 2) lead-based die adhesive used between the die and leadframe. The component is otherwise considered Pb-Free (RoHS compatible) as defined above. Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material) (3) MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.

www.ti.com 11-Apr-2013 Addendum-Page 3 (4) Multiple Top-Side Markings will be inside parentheses. Only one Top-Side Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation of the previous line and the two combined represent the entire Top-Side Marking for that device. Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and continues to take reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on incoming materials and chemicals. TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release. In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.

*All dimensions are nominal Device Package Type Package Drawing Pins SPQ Reel Diameter (mm) Reel Width W1 (mm) (mm) (mm) (mm) (mm) W (mm) Pin1 Quadrant LM2577SX-12 DDPAK/ TO-263 LM2577SX-12/NOPB DDPAK/ TO-263 LM2577SX-ADJ DDPAK/ TO-263 LM2577SX-ADJ/NOPB DDPAK/ TO-263 PACKAGE MATERIALS INFORMATION www.ti.com 8-Apr-2013 Pack Materials-Page 1

*All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) LM2577SX-12 DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0 LM2577SX-12/NOPB DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0 LM2577SX-ADJ DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0 LM2577SX-ADJ/NOPB DDPAK/TO-263 KTT 5 500 367.0 367.0 45.0 PACKAGE MATERIALS INFORMATION www.ti.com 8-Apr-2013 Pack Materials-Page 2

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