LM2759 www.ti.com SNVS577D–JUNE2008–REVISEDMAY2013 2 LM2759 1A Switched Capacitor Flash LED Driver with I C Compatible Interface CheckforSamples:LM2759 FEATURES APPLICATIONS 1 • Upto1AOutputCurrent • CameraFlashinCellularPhones 2 • SolutionArea<22mm2 DESCRIPTION • NoInductorRequired LM2759 is an integrated low-noise, high-current • 90%PeakEfficiency switched capacitor DC/DC converter with a regulated • Adaptive1x,1.5xand2xGainsforMaximum current source. The device requires only four small Efficiency ceramic capacitors making the total solution area less • LoadDisconnectinShutdown than 22 mm2 and the height less than 1 mm. The LM2759 is capable of driving loads up to 1A from a • AccurateInputCurrentControlDuringGain single-cell Li-Ion battery. Maximum efficiency is Transitions achieved over the input voltage range by actively • FlashTime-Out selecting the proper gain based on the LED forward • TXInputPinEnsuresSynchronizationwithRF voltageandcurrentrequirements. PowerAmplifierPulse The LED current can be programmed up to 1A via an • Torch,Flash,andIndicatorModes I2C-compatible interface, along with eight selectable Flash Time-Out durations. One high-current Flash • ExternalFlashEnableviaStrobeInputPin LED can be driven either in a high-power Flash mode • StrobeInputDisableviaI2C or a low-power Torch mode. The Strobe pin allows • ProgrammableFlashPulseDuration,and the flash to be toggled via a Flash enable signal from TorchandFlashCurrentsviaI2C-Compatible a camera module. The TX input pin limits the Flash Interface LED current to the Torch current level during a RF PA pulse, to reduce high loads on the battery. • 1MHzConstantFrequencyOperation Internal soft-start circuitry limits the amount of inrush • LowProfile12–PinWSON(3mmx3mmx currentduringstart-up. 0.8mm) LM2759 is offered in a small 12-pin thermally enhancedWSONpackage. Typical Application Circuit ILED = Up to 1A VIN = 3.0V - 5.5V VIN VOUT C1+ CIN 2.2 µF 4.7 µF COUT D1 C1 2.2 µF C1- ISINK C2+ LM2759 C2 2.2 µF C2- Strobe TX SDA SCL GND TDK: 2.2 µF – C1608X5R1C225 4.7 µF – C2012X5R1C475 1 Pleasebeawarethatanimportantnoticeconcerningavailability,standardwarranty,anduseincriticalapplicationsof TexasInstrumentssemiconductorproductsanddisclaimerstheretoappearsattheendofthisdatasheet. Alltrademarksarethepropertyoftheirrespectiveowners. 2 PRODUCTIONDATAinformationiscurrentasofpublicationdate. Copyright©2008–2013,TexasInstrumentsIncorporated Products conform to specifications per the terms of the Texas Instruments standard warranty. Production processing does not necessarilyincludetestingofallparameters.

LM2759 SNVS577D–JUNE2008–REVISEDMAY2013 www.ti.com Connection Diagram 1 12 12 1 2 11 11 2 3 10 10 3 4 9 9 4 5 8 8 5 6 7 7 6 Die-Attach Pad: GND Die-Attach Pad: GND Top View Bottom View Figure1. 12-PinWSONPackage 3mmx3mmx0.8mm PackageNumberDQB0012A PINDESCRIPTIONS Pin Name Description 10 V Inputvoltageconnection. IN 3 V Chargepumpregulatedoutput. OUT 12 C1− 11 C1+ Flyingcapacitorconnections. 2 C2+ 1 C2− 4 GND Groundconnection. 6 I Regulatedcurrentsinkinput. SINK 8 SDA SerialdataI/Opin. 7 Strobe Manualflashenablepin.FlashwillremainonforthedurationthattheStrobepinisheldhighor whentheFlashTimeoutoccurs,whichevercomesfirst. 5 TX TransmissionpulseFlashinterruptpin.High=RFPApulseactive,LEDcurrentreducedtoTorch level,Low=RFPApulseoff,LEDatfullprogrammedcurrentlevel. 9 SCL Serialclockpin. Thesedeviceshavelimitedbuilt-inESDprotection.Theleadsshouldbeshortedtogetherorthedeviceplacedinconductivefoam duringstorageorhandlingtopreventelectrostaticdamagetotheMOSgates. 2 SubmitDocumentationFeedback Copyright©2008–2013,TexasInstrumentsIncorporated ProductFolderLinks:LM2759

LM2759 www.ti.com SNVS577D–JUNE2008–REVISEDMAY2013 Absolute Maximum Ratings(1)(2)(3) V pin:VoltagetoGND -0.3Vto6.0V IN Strobe,TX,SDA,SCL,I pins:VoltagetoGND -0.3Vto(V +0.3V) SINK IN w/6.0Vmax ContinuousPowerDissipation(4) InternallyLimited JunctionTemperature(T ) 150°C J-MAX StorageTemperatureRange -65°Cto150°C MaximumLeadTemp.(Soldering) (5) ESDRating HumanBodyModel(6) 2.5KV (1) AbsoluteMaximumRatingsindicatelimitsbeyondwhichdamagetothecomponentmayoccur.OperatingRatingsareconditionsunder whichoperationofthedeviceisensured.OperatingRatingsdonotimplyensuredperformancelimits.Forensuredperformancelimits andassociatedtestconditions,seetheElectricalCharacteristicstables. (2) AllvoltagesarewithrespecttothepotentialtotheGNDpin. (3) IfMilitary/Aerospacespecifieddevicesarerequired,pleasecontacttheTexasInstrumentsSalesOffice/Distributorsforavailabilityand specifications. (4) Internalthermalshutdowncircuitryprotectsthedevicefrompermanentdamage.ThermalshutdownengagesatT=150°C(typ.)and J disengagesatT =120°C(typ.). J (5) Fordetailedsolderingspecificationsandinformation,pleaserefertoTexasInstrumentsApplicationNoteAN-1187(SNOA401). (6) TheHumanbodymodelisa100pFcapacitordischargedthrougha1.5kΩresistorintoeachpin.(MIL-STD-8833015.7) Operating Ratings(1)(2) InputVoltageRange 2.7Vto5.5V LEDVoltageRange 2.0Vto4.0V JunctionTemperatureRange(T) -30°Cto+125°C J AmbientTemperatureRange(T )(3) -30°Cto+85°C A (1) AbsoluteMaximumRatingsindicatelimitsbeyondwhichdamagetothecomponentmayoccur.OperatingRatingsareconditionsunder whichoperationofthedeviceisensured.OperatingRatingsdonotimplyensuredperformancelimits.Forensuredperformancelimits andassociatedtestconditions,seetheElectricalCharacteristicstables. (2) AllvoltagesarewithrespecttothepotentialtotheGNDpin. (3) Inapplicationswherehighpowerdissipationand/orpoorpackagethermalresistanceispresent,themaximumambienttemperaturemay havetobederated.Maximumambienttemperature(T )isdependentonthemaximumoperationjunctiontemperature(T = A-MAX J-MAX-OP 125ºC),themaximumpowerdissipationofthedeviceintheapplication(P ),andthejunction-toambientthermalresistanceofthe D-MAX part/packageintheapplication(θ ),asgivenbythefollowingequation:T =T -(θ ×P ). JA A-MAX J-MAX-OP JA D-MAX Thermal Information Junction-to-AmbientThermalResistance,(θ ), (1) 36.7°C/W JA (1) Junction-to-ambientthermalresistance(θ )istakenfromathermalmodelingresult,performedundertheconditionsandguidelinesset JA forthintheJEDECstandardJESD51-7.Thetestboardisa4–layerFR-4boardmeasuring102mmx76mmx1.6mmwitha2x1array ofthermalvias.Thegroundplaneontheboardis50mmx50mm.Thicknessofcopperlayersare53µm/35µm/35µm/53µm (1.5oz/1oz/1oz/1.5oz).Ambienttemperatureinsimulationis22°C,stillair.Powerdissipationis1W.Thevalueofθ ofthisproductinthe JA WSONpackagecouldfallinarangeaswideas30ºC/Wto150ºC/W(ifnotwider),dependingonPWBmaterial,layout,and environmentalconditions.Inapplicationswherehighmaximumpowerdissipationexists(highV ,highI ),specialcaremustbepaid IN OUT tothermaldissipationissues.Formoreinformationonthesetopics,pleaserefertoApplicationNoteAN-1187(SNOA401):andthe PowerEfficiencyandPowerDissipationsectionofthisdatasheet. Copyright©2008–2013,TexasInstrumentsIncorporated SubmitDocumentationFeedback 3 ProductFolderLinks:LM2759

LM2759 SNVS577D–JUNE2008–REVISEDMAY2013 www.ti.com Electrical Characteristics(1)(2) LimitsinstandardtypefaceareforT =25°C.Limitsinboldfacetypeapplyoverthefulloperatingjunctiontemperaturerange J (-30°C≤T ≤+125°C).Unlessotherwisenoted,specificationsapplytotheLM2759TypicalApplicationCircuit(pg.1)withV J IN =3.6V,V =0V,V =0V,C =C =C =2.2µF,C =4.7µF.(3) TX STROBE IN 1 2 OUT Symbol Parameter Conditions Min Typ Max Units I LEDCurrentSinkAccuracy FlashMode 198 220 242 mA LED ADDRxB0=0x02 −10% +10% I MaxFlashOutputCurrent FlashMode 1 A FLASH ADDRxB0=0x0F V GainTransitionVoltage I =500mA 350 mV GDX LED ThresholdonI (V falling) SINK ISINK V OutputVoltage 1xMode,I =0mA(V >V )(4) 4.7 4.9 OUT OUT IN OUT 1.5xMode,I =0mA 4.7 4.9 V OUT 2xMode,I =0mA 5.1 5.4 OUT R x1ModeOutputImpedance I =200mA,V =3.3V 0.33 OUT OUT IN 1.5xModeOutput I =500mA,V =3.3V 1.9 Ω OUT IN Impedance x2ModeOutputImpedance 2.25 F SwitchingFrequency 2.7V≤V ≤5.5V 0.7 1 1.3 MHz SW IN V InputLogicHigh Pins:TX,Strobe 1.26 V IH V InputLogicLow Pins:TX,Strobe 0.7 V IL I =0mA,1xMode 0.6 0.9 OUT I QuiescentCurrent I =0mA,1.5xMode 3.4 4.0 mA Q OUT I =0mA,2xMode 5.9 7.0 OUT I ShutdownCurrent DeviceDisabled 5.8 9.7 µA SD 2.7V≤V ≤5.5V IN I2CCompatibleInterfaceVoltageSpecifications(SCL,SDA) V InputLogicLow“0” 2.7V≤V ≤5.5V 0.72 V IL IN V InputLogicHigh“1' 2.7V≤V ≤5.5V 1.25 V IH IN V OutputLogicLow“0” I =3mA 300 mV OL LOAD I2CCompatibleInterfaceTimingVoltageSpecifications(SCL,SDA)(5) t SCL(ClockPeriod) 2.5 µs 1 t DatainSetupTimetoSCL 100 ns 2 High t DataOutStableAfterSCL 0 ns 3 Low t SDALowSetupTimeto 100 ns 4 SCLLow(Start) t SDAHighHoldTimeAfter 100 ns 5 SCLHigh(Stop) (1) AllvoltagesarewithrespecttothepotentialtotheGNDpin. (2) MinandMaxlimitsarespecifiedbydesign,test,orstatisticalanalysis.Typical(Typ)numbersarenotensured,butdorepresentthe mostlikelynorm.Unlessotherwisespecified,conditionsforTypspecificationsare:V =3.6VandT =25°C. IN A (3) C ,C ,C ,C :Low-ESRSurface-MountCeramicCapacitors(MLCCs)usedinsettingelectricalcharacteristics. IN OUT 1 2 (4) Forinputvoltagebelowtheregulationtargetduringthegainof1x,theoutputvoltagewilltypicallybeequaltotheinputvoltage. (5) SCLandSDAshouldbeglitch-freeinorderforproperbrightnesscontroltoberealized. 4 SubmitDocumentationFeedback Copyright©2008–2013,TexasInstrumentsIncorporated ProductFolderLinks:LM2759

LM2759 www.ti.com SNVS577D–JUNE2008–REVISEDMAY2013 Block Diagram COUT 4.7 µF FLASH D LED MODULE VOUT VIN Gain Thermal CIN 2.2 µF Control VREF Shutdown FLASH C1+ Timeout 2.2 µF VROEUGT Current GND Control C1- STROBE C2+ 1x,1.5x, 2x TX 2.2 µF Charge I2C Control Power Pump Logic on Reset C2- LM2759 SCL SDA Copyright©2008–2013,TexasInstrumentsIncorporated SubmitDocumentationFeedback 5 ProductFolderLinks:LM2759

LM2759 SNVS577D–JUNE2008–REVISEDMAY2013 www.ti.com Typical Performance Characteristics Unlessotherwisespecified:T =25°C,V =3.6V,C =C =C =2.2µF,C =4.7µF.Capacitorsarelow-ESRmulti-layer A IN IN 1 2 OUT ceramiccapacitors(MLCC's).LuxeonPWF3FlashLED. Efficiency InputCurrent vs vs V V IN IN Figure2. Figure3. QuiescentCurrent QuiescentCurrent vs vs V ,Gain=1X V ,Gain=2X IN IN Figure4. Figure5. I ShutdownCurrent LED vs vs V V ISINK IN Figure6. Figure7. 6 SubmitDocumentationFeedback Copyright©2008–2013,TexasInstrumentsIncorporated ProductFolderLinks:LM2759

LM2759 www.ti.com SNVS577D–JUNE2008–REVISEDMAY2013 Typical Performance Characteristics (continued) Unlessotherwisespecified:T =25°C,V =3.6V,C =C =C =2.2µF,C =4.7µF.Capacitorsarelow-ESRmulti-layer A IN IN 1 2 OUT ceramiccapacitors(MLCC's).LuxeonPWF3FlashLED. OscillatorFrequency vs V TorchCodeLevels IN Figure8. Figure9. FlashCodeLevels ShutdowntoTorchMode,100mA CH1:SDA;Scale:2V/Div,DCCoupled CH2:V ;Scale:2V/Div,DCCoupled OUT CH3:I ;Scale:100mA/Div,DCCoupled IN CH4:I ;Scale:100mA/Div,DCCoupled LED Timescale:400µs/Div Figure10. Figure11. ShutdowntoFlashMode,1A TorchtoFlashMode,100mAto1A CH1:SDA;Scale:2V/Div,DCCoupled CH1:SDA;Scale:2V/Div,DCCoupled CH2:VOUT;Scale:2V/Div,DCCoupled CH2:VOUT;Scale:2V/Div,DCCoupled CH3:IIN;Scale:1A/Div,DCCoupled CH3:IIN;Scale:1A/Div,DCCoupled CH4:ILED;Scale:1A/Div,DCCoupled CH4:ILED;Scale:1A/Div,DCCoupled Timescale:1ms/Div Timescale:1ms/Div Figure12. Figure13. Copyright©2008–2013,TexasInstrumentsIncorporated SubmitDocumentationFeedback 7 ProductFolderLinks:LM2759

LM2759 SNVS577D–JUNE2008–REVISEDMAY2013 www.ti.com Typical Performance Characteristics (continued) Unlessotherwisespecified:T =25°C,V =3.6V,C =C =C =2.2µF,C =4.7µF.Capacitorsarelow-ESRmulti-layer A IN IN 1 2 OUT ceramiccapacitors(MLCC's).LuxeonPWF3FlashLED. FlashTimeout,TimeoutCode(x03)=325ms TorchLevel(x0F)=180mA,FlashLevel(x05)=410mA CH1(bottom):I ;Scale:200mA/Div,DCCoupled IN CH2(middle):SDA;Scale:2V/Div,DCCoupled CH3(top):V ;Scale:2V/Div,DCCoupled OUT Timescale:100ms/Div Figure14. 8 SubmitDocumentationFeedback Copyright©2008–2013,TexasInstrumentsIncorporated ProductFolderLinks:LM2759

LM2759 www.ti.com SNVS577D–JUNE2008–REVISEDMAY2013 APPLICATION INFORMATION CIRCUIT DESCRIPTION The LM2759 is an adaptive CMOS charge pump with gains of 1x, 1.5x, and 2x, optimized for driving Flash LEDs incameraphonesandotherportableapplications.Itprovidesaconstantcurrentofupto1A(typ.)forFlashmode and180mA(typ.)forTorchmode. The LM2759 has selectable modes including Flash, Torch, Indicator and Shutdown. Flash mode for the LM2759 can also be enabled via the Strobe input pin. The LED is driven from V and connected to the current sink. OUT The LED drive current and operating modes are programmed via an I2C compatible interface. The LM2759 adaptivelyselectsthenexthighestgainmodewhenneededtomaintaintheprogrammedLEDcurrentlevel. To prevent a high battery load condition during a simultaneous RF PA transmission and Flash event, LM2759 has a Flash interrupt pin (TX) to reduce the LED current to the programmed Torch current level for the duration oftheRFPAtransmissionpulse. CHARGE PUMP AND GAIN TRANSITIONS The input to the 1x, 1.5x, 2x charge pump is connected to the V pin, and the loosely regulated output of the IN charge pump is connected to the V pin. In 1x mode, as long as the input voltage is less than 4.7V (typ.), the OUT output voltage is approximately equal to the input voltage. When the input voltage is over 4.7V (typ.) the output voltage is regulated to 4.7V (typ.). In 1.5x mode, the output voltage is regulated to 4.7V (typ.) over entire input voltage range. For the gain of 2x, the output voltage is regulated to 5.1V (typ.). When under load, the voltage at V can be less than the target regulation voltage while the charge pump is still in closed loop operation. This is OUT duetotheloadregulationtopologyoftheLM2759. Thechargepump’sgainisselectedaccordingtotheheadroomvoltageacrossthecurrentsinkofLM2759.When the headroom voltage V (at the LED cathode) drops below 350 mV (typ.) the charge pump gain transitions to GDX thenextavailablehighergainmode.Oncethechargepumptransitionstoahighergain,itwillremainatthatgain for as long as the device remains enabled. Shutting down and then re-enabling the device resets the gain mode totheminimumgainrequiredtomaintaintheload. SOFTSTART The LM2759 contains internal soft-start circuitry to limit inrush currents when the part is enabled. Soft start is implementedinternallywithacontrolledturn-onoftheinternalvoltagereference. CURRENTLIMITPROTECTION The LM2759 charge pump contains current limit protection circuitry that protects the device during V fault OUT conditionswhereexcessivecurrentisdrawn.Outputcurrentislimitedto1.4Atypically. LOGICCONTROLPINS LM2759 has two asynchronous logic pins, Strobe and TX. These logic inputs function according to the table below: TX STROBE FUNCTION 0 0 CurrentI2Cprogrammedstate(Off,Torch, Flash,Indicator) 1 0 CurrentI2Cprogrammedstate(Off,Torch, Flash,Indicator).IfFlashisenabledviaI2C andTXislogicHigh,theLEDcurrentwillbe attheprogrammedTorchlevel. 0 1 FlashMode(TotalLED"ON"Durationlimited byFlashTimeout) 1 1 TorchMode(TotalLED"ON"Durationlimited byFlashTimeout) Copyright©2008–2013,TexasInstrumentsIncorporated SubmitDocumentationFeedback 9 ProductFolderLinks:LM2759

LM2759 SNVS577D–JUNE2008–REVISEDMAY2013 www.ti.com I2CCOMPATIBLEINTERFACE STARTANDSTOPCONDITIONS START and STOP conditions classify the beginning and the end of the I2C session. A START condition is defined as SDA signal transitioning from HIGH to LOW while SCL line is HIGH. A STOP condition is defined as the SDA transitioning from LOW to HIGH while SCL is HIGH. The I2C master always generates START and STOPconditions.TheI2CbusisconsideredtobebusyafteraSTARTconditionandfreeafteraSTOPcondition. During data transmission, the I2C master can generate repeated START conditions. First START and repeated STARTconditionsareequivalent,function-wise. SDA SCL S P START condition STOPcondition Figure15. StartandStopConditions DATAVALIDITY The data on SDA line must be stable during the HIGH period of the clock signal (SCL). In other words, state of thedatalinecanonlybechangedwhenSCLisLOW. SCL SDA data data data data data change valid change valid change allowed allowed allowed Figure16. DataValidityDiagram A pull-up resistor between the controller's VIO line and SDA must be greater than [(VIO-V ) / 3.5mA] to meet OL the V requirement on SDA. Using a larger pull-up resistor results in lower switching current with slower edges, OL whileusingasmallerpull-upresultsinhigherswitchingcurrentswithfasteredges. TRANSFERINGDATA Every byte put on the SDA line must be eight bits long, with the most significant bit (MSB) transferred first. Each byte of data has to be followed by an acknowledge bit. The acknowledge related clock pulse is generated by the master. The master releases the SDA line (HIGH) during the acknowledge clock pulse. The LM2759 pulls down the SDA line during the 9th clock pulse, signifying an acknowledge. The LM2759 generates an acknowledge aftereachbyteisreceived. After the START condition, the I2C master sends a chip address. This address is seven bits long followed by an eighth bit which is a data direction bit (R/W). The LM2759 address is 53h. For the eighth bit, a “0” indicates a WRITE and a “1” indicates a READ. The second byte selects the register to which the data will be written. The thirdbytecontainsdatatowritetotheselectedregister. 10 SubmitDocumentationFeedback Copyright©2008–2013,TexasInstrumentsIncorporated ProductFolderLinks:LM2759

LM2759 www.ti.com SNVS577D–JUNE2008–REVISEDMAY2013 ack from slave ack from slave ack from slave start msb Chip Address lsb w ack msb Register Add lsb ack msb DATA lsb ack stop SCL SDA start Id = 53h w ack addr = 10h ack GDWD(cid:3)K¶03 (Flash) ack stop w=write(SDA="0") r=read(SDA="1") ack=acknowledge(SDApulleddownbyeithermasterorslave) id=chipaddress,53hforLM2759 Figure17. WriteCycle I2CCOMPATIBLECHIPADDRESS ThechipaddressforLM2759is1010011,or53h. MSB LSB ADR6 ADR5 ADR4 ADR3 ADR2 ADR1 ADR0 R/W bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0 01 10 11 00 10 11 01 2 IC SLAVE address (chip address) INTERNALREGISTERS General Purpose MSB Register Address: 0x10 LSB 1 1 1 1 G4 G2 G1 G0 bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0 Torch Current MSB Register Address: 0xA0 LSB 1 1 1 1 A3 A2 A1 A0 bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0 Flash Current MSB Register Address: 0xB0 LSB 1 1 1 1 B3 B2 B1 B0 bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0 Flash Timeout Duration MSB Register Address: 0xC0 LSB 1 1 1 1 1 C2 C1 C0 bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0 PowerOnValue Register InternalHexAddress (lowest4bits) GeneralPurposeRegister 10h 0000 FlashCurrentRegister B0h 1010 TorchCurrentRegister A0h 0111 Copyright©2008–2013,TexasInstrumentsIncorporated SubmitDocumentationFeedback 11 ProductFolderLinks:LM2759

LM2759 SNVS577D–JUNE2008–REVISEDMAY2013 www.ti.com PowerOnValue Register InternalHexAddress (lowest4bits) FlashTimeoutDurationRegister C0h 1011 GENERALPURPOSEREGISTERANDSTROBEINHIBITFUNCTION The general purpose register (x10) is used set the mode of operation for the LM2759. The selectable operating modesusingthelower4bitsinthegeneralpurposeregisterarelistedinthetablebelow. TheStrobeInputPincanbedisabledviaI2Ctoignoreexternalsignalsintothispinwhendesired.Thisfunctionis implemented through bit 3 of the General Purpose Register (See table below). In the default state, input signals ontheStrobeInputareenabled.(Bit3=“0”,inputsintotheStrobePinarenotinhibited). Table1.GeneralPurposeRegister(Regx10) Bit3 Bit2 Bit1 Bit0 Mode X X X 0 Shutdown X 0 0 1 Torch X X 1 1 Flash X 1 0 1 Indicator(LowestTorchLevel) 1 X X X InhibitInputsintotheStrobePin SETTINGLEDCURRENT The current through the LED is set by programming the appropriate register with the desired current level code for Flash and Torch. The time that Flash mode is active is dependent on the lesser of the duration that it is set to "ON" (via I2C or the Strobe pin), or the duration of the Flash Timeout. Use the tables below to select the desired currentlevel. Using the part in conditions where the junction temperature might rise above the rated maximum requires that the operating ranges and/or conditions be de-rated. The printed circuit board also must be carefully laid out to accountforhighthermaldissipationinthepart. Table2.FlashCurrentTable(RegxB0) CODE(Hex) FLASHCURRENT(mA) 00 80 01 150 02 220 03 280 04 350 05 410 06 470 07 530 08 590 09 650 0A 710 0B 770 0C 830 0D 890 0E 950 0F 1010 12 SubmitDocumentationFeedback Copyright©2008–2013,TexasInstrumentsIncorporated ProductFolderLinks:LM2759

LM2759 www.ti.com SNVS577D–JUNE2008–REVISEDMAY2013 Table3.TorchCurrentTable(RegxA0) CODE(Hex) TORCHCURRENT(mA) 00 15 01 30 02 40 03 50 04 65 05 80 06 90 07 100 08 110 09 120 0A 130 0B 140 0C 150 0D 160 0E 170 0F 180 FLASHTIME-OUTFEATURE Time-out Protection Circuitry disables the current sink when either the Strobe pin is held at logic high or the Flash mode is enabled via the I2C compatible interface longer than the programmed timeout duration. This prevents the device from self-heating due to the high power dissipation during Flash conditions. During the time- out condition, voltage will still be present on V but the current sink will be shut off, resulting in no current OUT through the Flash LED. When the device goes into a time-out condition, disabling and then re-enabling the devicewillresetthetime-out.UsethetablebelowtosetthedesiredFlashtimeoutduration. Table4.FlashTimeoutDuration(RegxC0) CODE(Hex) TIME(ms) 00 60 01 125 02 250 03 375 04 500 05 625 06 750 07 1100 CAPACITORSELECTION The LM2759 requires 4 external capacitors for proper operation. Surface-mount multi-layer ceramic capacitors arerecommended.Thesecapacitorsaresmall,inexpensiveandhaveverylowequivalentseriesresistance(ESR <20 mΩ typ.). Tantalum capacitors, OS-CON capacitors, and aluminum electrolytic capacitors are not recommended for use with the LM2759 due to their high ESR, as compared to ceramic capacitors. For most applications, ceramic capacitors with X7R or X5R temperature characteristic are preferred for use with the LM2759. These capacitors have tight capacitance tolerance (as good as ±10%) and hold their value over temperature (X7R: ±15% over -55°C to 125°C; X5R: ±15% over -55°C to 85°C). Capacitors with Y5V or Z5U temperature characteristic are generally not recommended for use with the LM2759. Capacitors with these temperature characteristics typically have wide capacitance tolerance (+80%, -20%) and vary significantly over Copyright©2008–2013,TexasInstrumentsIncorporated SubmitDocumentationFeedback 13 ProductFolderLinks:LM2759

LM2759 SNVS577D–JUNE2008–REVISEDMAY2013 www.ti.com temperature (Y5V: +22%, -82% over -30°C to +85°C range; Z5U: +22%, -56% over +10°C to +85°C range). Under some conditions, a nominal 1 μF Y5V or Z5U capacitor could have a capacitance of only 0.1 μF. Such detrimental deviation is likely to cause Y5V and Z5U capacitors to fail to meet the minimum capacitance requirements of the LM2759. The voltage rating of the output capacitor should be 6.3V or more. For example, a 6.3V 0603 4.7 μF output capacitor (TDK C1608X5R0J475) is acceptable for use with the LM2759, as long as the capacitance on the output does not fall below a minimum of 3μF in the intended application. All other capacitors should have a voltage rating at or above the maximum input voltage of the application and should have a minimumcapacitanceof1μF. Table5.SuggestedCapacitorsandSuppliers MFGPartNo. Type MFG VoltageRating CaseSize Inch(mm) 4.7µFforC OUT C1608X5R0J475 CeramicX5R TDK 6.3V 0603(1608) JMK107BJ475 CeramicX5R Taiyo-Yuden 6.3V 0603(1608) 2.2µFforC1,C2,C IN C1608X5R0J225 CeramicX5R TDK 6.3V 0603(1608) JMK107BJ225 CeramicX5R Taiyo-Yuden 6.3V 0603(1608) POWEREFFICIENCY Efficiency of LED drivers is commonly taken to be the ratio of power consumed by the LED (P ) to the power LED drawn at the input of the part (P ). With a 1x, 1.5x, 2x charge pump, the input current is equal to the charge IN pumpgaintimestheoutputcurrent(totalLEDcurrent).TheefficiencyoftheLM2759canbepredictedasfollows: P =V ×I (1) LED LED LED P =V ×I (2) IN IN IN P =V ×(Gain×I +I ) (3) IN IN LED Q E=(P ÷P ) (4) LED IN For a simple approximation, the current consumed by internal circuitry (I ) can be neglected, and the resulting Q efficiencywillbecome: E=V ÷(V ×Gain) (5) LED IN Neglecting I will result in a slightly higher efficiency prediction, but this impact will be negligible due to the value Q of I being very low compared to the typical Torch and Flash current levels (100mA - 1A). It is also worth noting Q that efficiency as defined here is in part dependent on LED voltage. Variation in LED voltage does not affect power consumed by the circuit and typically does not relate to the brightness of the LED. For an advanced analysis, it is recommended that power consumed by the circuit (V x I ) be evaluated rather than power IN IN efficiency. THERMALPROTECTION Internal thermal protection circuitry disables the LM2759 when the junction temperature exceeds 150°C (typ.). This feature protects the device from being damaged by high die temperatures that might otherwise result from excessive power dissipation. The device will recover and operate normally when the junction temperature falls below 120°C (typ.). It is important that the board layout provide good thermal conduction to keep the junction temperaturewithinthespecifiedoperatingratings. POWERDISSIPATION The power dissipation (P ) and junction temperature (T ) can be approximated with the equations DISSIPATION J below. P is the power generated by the 1x, 1.5x, 2x charge pump, P is the power consumed by the LED, T IN LED A is the ambient temperature, and θ is the junction-to-ambient thermal resistance for the 12 pin WSON package. JA V is the input voltage to the LM2759, V is the nominal LED forward voltage, and I is the programmed IN LED LED LEDcurrent. P =P -P (6) DISSIPATION IN LED =(Gain×V ×I )−(V ×I ) (7) IN LED LED LED T =T +(P ×θ ) (8) J A DISSIPATION JA 14 SubmitDocumentationFeedback Copyright©2008–2013,TexasInstrumentsIncorporated ProductFolderLinks:LM2759

LM2759 www.ti.com SNVS577D–JUNE2008–REVISEDMAY2013 The junction temperature rating takes precedence over the ambient temperature rating. The LM2759 may be operated outside the ambient temperature rating, so long as the junction temperature of the device does not exceed the maximum operating rating of 105°C. The maximum ambient temperature rating must be derated in applications where high power dissipation and/or poor thermal resistance causes the junction temperature to exceed105°C. MAXIMUMOUTPUTCURRENT The maximum LED current that can be used for a particular application depends on the rated forward voltage of the LED used, the input voltage range of the application, and the Gain mode of the LM2759’s charge pump. The following equation can be used to approximate the relationship between the maximum LED current, the LED forwardvoltage,theminimuminputvoltage,andthechargepumpgain: (V xGain)>(V +V )+(I xR ) (9) IN_MIN F HR LED OUT_GAIN V or the voltage required across the current sink to remain in regulation can be approximated by (I x K ), HR LED HR where K is 0.8 mV/mA (typ). R is the output impedance of the charge pump according to its gain HR OUT_GAIN mode. When using the equation above, keep in mind that the (V + V ) portion of the equation can not be F HR greater than the nominal output regulation voltage for a particular gain. In other words, when making calculations for an application where the term (V + V ) is higher than a particular gain’s regulation voltage, the next higher F HR gainlevelmustbeusedforthecalculation. Example:V =4V@1A,ChargePumpintheGainof2xwithaR of2.25Ω(typ.) F OUT V >[(4V+0.8V)+(1Ax2.25Ω)]÷2 IN_MIN V >3.53V(typ.) IN_MIN The maximum power dissipation in the LM2759 must also be taken into account when selecting the conditions for an application, such that the junction temperature of the device never exceeds its rated maximum. The input voltage range, operating temperature range, and/or current level of the application may have to be adjusted to keeptheLM2759withinnormaloperatingratings. BOARDLAYOUTCONSIDERATIONS PC board layout is an important part of DC-DC converter design. Poor board layout can disrupt the performance of a DC-DC converter and surrounding circuitry by contributing to EMI, ground bounce, and resistive voltage loss in the traces. These can send erroneous signals to the DC-DC converter IC, resulting in poor regulation or instability. Poor layout can also result in re-flow problems leading to poor solder joints between the WSON packageandboardpads.Poorsolderjointscanresultinerraticordegradedperformance. Copyright©2008–2013,TexasInstrumentsIncorporated SubmitDocumentationFeedback 15 ProductFolderLinks:LM2759

LM2759 SNVS577D–JUNE2008–REVISEDMAY2013 www.ti.com REVISION HISTORY ChangesfromRevisionC(May2013)toRevisionD Page • ChangedlayoutofNationalDataSheettoTIformat.......................................................................................................... 15 16 SubmitDocumentationFeedback Copyright©2008–2013,TexasInstrumentsIncorporated ProductFolderLinks:LM2759

PACKAGE OPTION ADDENDUM www.ti.com 6-Feb-2020 PACKAGING INFORMATION Orderable Device Status Package Type Package Pins Package Eco Plan Lead/Ball Finish MSL Peak Temp Op Temp (°C) Device Marking Samples (1) Drawing Qty (2) (6) (3) (4/5) LM2759SD/NOPB ACTIVE WSON DQB 12 1000 Green (RoHS SN Level-3-260C-168 HR -30 to 85 L2759 & no Sb/Br) LM2759SDX/NOPB ACTIVE WSON DQB 12 4500 Green (RoHS SN Level-3-260C-168 HR -30 to 85 L2759 & no Sb/Br) (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) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may reference these types of products as "Pb-Free". RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption. Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based flame retardants must also meet the <=1000ppm threshold requirement. (3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature. (4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device. (5) Multiple Device Markings will be inside parentheses. Only one Device 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 Device Marking for that device. (6) Lead/Ball Finish - Orderable Devices may have multiple material finish options. Finish options are separated by a vertical ruled line. Lead/Ball Finish values may wrap to two lines if the finish value exceeds the maximum column width. 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. Addendum-Page 1

PACKAGE OPTION ADDENDUM www.ti.com 6-Feb-2020 Addendum-Page 2

PACKAGE MATERIALS INFORMATION www.ti.com 20-Sep-2016 TAPE AND REEL INFORMATION *Alldimensionsarenominal Device Package Package Pins SPQ Reel Reel A0 B0 K0 P1 W Pin1 Type Drawing Diameter Width (mm) (mm) (mm) (mm) (mm) Quadrant (mm) W1(mm) LM2759SD/NOPB WSON DQB 12 1000 178.0 12.4 3.3 3.3 1.0 8.0 12.0 Q1 LM2759SDX/NOPB WSON DQB 12 4500 330.0 12.4 3.3 3.3 1.0 8.0 12.0 Q1 PackMaterials-Page1

PACKAGE MATERIALS INFORMATION www.ti.com 20-Sep-2016 *Alldimensionsarenominal Device PackageType PackageDrawing Pins SPQ Length(mm) Width(mm) Height(mm) LM2759SD/NOPB WSON DQB 12 1000 210.0 185.0 35.0 LM2759SDX/NOPB WSON DQB 12 4500 367.0 367.0 35.0 PackMaterials-Page2

MECHANICAL DATA DQB0012A SDF12A (Rev B) www.ti.com

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