TPS81256

TPS81256 TI1 | Alldatasheet

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0.1 0.2 0.4 0.8 VI - Input Voltage - V Efficiency - % IO - Output Current - mA V = 5.0 VO CI CO L VIN EN VOUT GND L VOUT = 5.0 VDC/DC Converter TPS81256SIP ENABLE GND 4.7µF 16V X5R (0603) VIN 2.5 V .. 4.85 V TPS81256 www.ti.com SLVSAZ9 –JUNE 2012 3-W,HIGHEFFICIENCYSTEP-UPCONVERTERINMicroSiP™ PACKAGING Check forSamples: TPS81256 1FEATURES DESCRIPTION 2• 91% Efficiencyat4MHz Operation The TPS8125x device is a complete MicroSiP™

• Wide VIN Range From 2.5Vto5.5V DC/DC step-uppower solutionintendedforbattery- powered portable applications.Included in the• IOUT ≥550mA atVOUT = 5.0V,VIN ≥3.3V package are the switchingregulator,inductorand• ±2% TotalDC VoltageAccuracy input/outputcapacitors.Only a tinyadditionaloutput• 43µA Supply Current capacitorisrequiredtofinishthedesign.
• Best-in-ClassLineand Load Transient The TPS8125x is based on a high-frequency
• VIN ≥ VOUT Operation synchronousstep-upDC/DC converteroptimizedfor battery-poweredportableapplications.• Low-RippleLight-LoadPFM Mode
• True Load DisconnectDuring Shutdown The DC/DC converteroperatesata regulated4-MHz switchingfrequencyand enterspower-save mode• Thermal Shutdown and Overload Protection operationat lightload currentsto maintainhigh• Sub 1-mm ProfileSolution efficiencyovertheentireloadcurrentrange.
• TotalSolutionSize<9mm 2 The PFM mode extendsthe batterylifeby reducing• 9-PinMicroSiPTM Packaging the supply currentto 43μA (typ)duringlightload operation.Intendedforlow-power applications,theAPPLICATIONS TPS8125x supportsmore than3W outputpower over a fullLi-Ionbatteryvoltagerange.Inputcurrentin• CellPhones, Smart-Phones,TabletPCs shutdown mode is less than 1µA (typ),which• Mono and StereoAPA Applications maximizesbatterylife.
• USB-OTG, HDMI Applications The TPS8125x offersa very smallsolutionsizeof• USB Charging Port(5V) lessthan 9mm 2 due to minimum amount of external components.The solutionispackaged ina compact (2.6mm x 2.9mm) and low profile(1.0mm) BGA package suitablefor automated assembly by standardsurfacemount equipment. Figure2. SmallestSolutionSizeApplication Figure1. Efficiencyvs.Load Current Pleasebe aware thatan importantnoticeconcerningavailability,standardwarranty,and use incriticalapplicationsof Texas Instrumentssemiconductorproductsand disclaimerstheretoappearsattheend ofthisdatasheet. 2MicroSiPisa trademarkofTexas Instruments. UNLESS OTHERWISE NOTED this document contains Copyright© 2012,Texas InstrumentsIncorporatedPRODUCTION DATA informationcurrentas of publicationdate. Products conform to specificationsper the terms of Texas Instrumentsstandardwarranty.Productionprocessingdoes not necessarilyincludetestingofallparameters.

SLVSAZ9 –JUNE 2012 www.ti.com These deviceshave limitedbuilt-inESD protection.The leadsshouldbe shortedtogetherorthedeviceplacedinconductivefoam duringstorageorhandlingtopreventelectrostaticdamage totheMOS gates. AVAILABLE DEVICE OPTION PACKAGEDEVICEPART NUMBER (1) OUTPUT VOLTAGE (2) ORDERING (2) MARKINGSPECIFIC FEATURES CHIP CODE TPS81256 5.0V TPS81256SIP TT TPS81257 (3) 5.1V TPS81257SIP (1) Forthemost currentpackage and orderinginformation,see thePackage OptionAddendum attheend ofthisdocument,orsee theTI websiteatwww.ti.com. TPS81256SIPT) toorderquantitiesof250 parts. (3) Productpreview.ContactTIfactoryformore information ABSOLUTE MAXIMUM RATINGS overoperatingfree-airtemperaturerange(unlessotherwisenoted)(1) UNIT Inputvoltage TPS8125x VoltageatVIN(2),VOUT (2),EN (2) –0.3to6 V ContinuousaveragecurrentintoVIN(3) 1.05 A Inputcurrent TPS8125x PulsedcurrentintoVIN(4) 1.3 A Power dissipation Internallylimited Operatingtemperaturerange,TA Temperaturerange Operatingvirtualjunction,TJ –40 to150 °C Storagetemperaturerange,Tstg –55 to125 °C Human Body Model -(HBM) 2000 V ESD rating(6) Charge DeviceModel -(CDM) 1000 V Machine Model -(MM) 200 V (1) Stressesbeyond thoselistedunderabsolutemaximum ratingsmay cause permanentdamage tothedevice.These arestressratings only,and functionaloperationofthedeviceattheseorany otherconditionsbeyond thoseindicatedunderrecommended operating conditionsisnotimplied.Exposuretoabsolute-maximum-ratedconditionsforextendedperiodsmay affectdevicereliability. (2) Allvoltagesarewithrespecttonetworkgroundterminal. (3) Limitthejunctionand the(topside)inductorcase temperatureto110°C, limitthe(topside)capacitorcase temperatureto85°C for 2000h operationatmaximum outputpower.ContactTIformore detailson lifetimeestimation. (4) Limitthe(topside)inductorcase temperatureto140°C and the(topside)capacitortemperatureto115°C for100h operation.ContactTI formore detailson lifetimeestimation. (5) Inapplicationswhere highpower dissipationand/orpoorpackage thermalresistanceispresent,themaximum ambienttemperaturemay have tobe derated.Maximum ambienttemperature(TA(max))isdependenton themaximum operatingjunctiontemperature(TJ(max)),the maximum power dissipationofthedeviceintheapplication(PD(max)),and thejunction-to-ambientthermalresistanceofthepart/package intheapplication(θJA),as givenby thefollowingequation:TA(max)= TJ(max)–(θJA X PD(max)).To achieveoptimum performance,itis recommended tooperatethedevicewitha maximum junctiontemperatureof125°C, a maximum inductorcase temperatureof125°C and a maximum capacitorcase temperatureof85°C. (6) The human body model isa 100-pFcapacitordischargedthrougha 1.5-kΩ resistorintoeach pin.The machine model isa 200-pF capacitordischargeddirectlyintoeach pin.

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www.ti.com SLVSAZ9 –JUNE 2012 THERMAL INFORMATION TPS8125x THERMAL METRIC (1)(2) SIP UNIT

9 PINS

θJA Junction-to-ambientthermalresistance 62 ψJB Junction-to-boardcharacterizationparameter 31 °C/W ψJT Junction-to-case(top)thermalresistance (1) Formore informationabouttraditionaland new thermalmetrics,see theIC Package ThermalMetricsapplicationreport,SPRA953 . (2) Thermaldatahave been simulatedwithhigh-Kboard(perJEDEC standard). RECOMMENDED OPERATING CONDITIONS MIN NOM MAX UNIT VI Inputvoltagerange TPS81256 2.5 5.5 V R L Minimum resistiveloadforstart-up(VI≤ 4.8V) TPS81256 65 Ω C EXT Outputcapacitance 2 30 µF TA Ambienttemperature –40 85 °C TJ Operatingjunctiontemperature –40 125 °C TCASE_IND Operatinginductorcase temperature 125 °C TCASE_CAP Operatingcapacitorcase temperature 85 °C

ELECTRICAL CHARACTERISTICS

Minimum and maximum valuesareatVIN = 2.5Vto5.5V,VOUT = 5.0V(orVIN,whicheverishigher),EN = 1.8V,TA = –40°C to 85°C; CircuitofParameterMeasurement Informationsection(unlessotherwisenoted).TypicalvaluesareatVIN = 3.6V,VOUT = 5.0V,EN = 1.8V,TA = 25°C (unlessotherwisenoted). PARAMETER TEST CONDITIONS MIN TYP MAX UNIT SUPPLY CURRENT OperatingquiescentcurrentintoVIN (1) IOUT = 0mA, VOUT = 5.0V,VIN = 3.6V 30 50 µA IQ TPS8125X EN = VIN OperatingquiescentcurrentintoVOUT (1) 7 20 µADevicenotswitching ISD Shutdown current(1) TPS8125x EN = GND 0.85 5.0 μA Falling 2.0 2.1 V VUVLO Under-voltagelockoutthreshold TPS81256 Hysteresis 0.1 V ENABLE VIL Low-levelinputvoltage 0.4 V VIH High-levelinputvoltage TPS8125x 1.0 V Ilkg Inputleakagecurrent InputconnectedtoGND orVIN 0.5 µA OUTPUT 3.3V≤ VIN ≤ 4.85V,0mA ≤ IOUT ≤ 550mAVOUT RegulatedDC outputvoltage TPS81256 4.85 5 5.2 VPFM/PWM operation 2.9V≤ VIN ≤ 4.85V,0mA ≤ IOUT ≤ 450mA 4.85 5 5.2 VPFM/PWM operation Power-savemode outputripplevoltage PFM operation,IOUT = 1mA 35 mVpk ΔVOUT TPS81256 PWM mode outputripplevoltage PWM operation,IOUT = 200mA 8 mVpk POWER SWITCH rDS(on) Input-to-outputOn-resistance TPS8125x VI= 5.25V.Devicenotswitching 320 m Ω Ilkg ReverseleakagecurrentintoVOUT (1) TPS81256 EN = GND 5 µA ILIM Averageinputcurrentlimit TPS8125x EN = VIN.VIN = 3.3V 1180 mA Overtemperatureprotection 140 °C TPS8125x Overtemperaturehysteresis 20 °C (1) Maximum valuescan varyoverlifetimedue tointrinsiccapacitorageingeffects.Formore details,refertoTHERMAL AND RELIABILITY INFORMATION section. Copyright© 2012,Texas InstrumentsIncorporated SubmitDocumentationFeedback 3 ProductFolderLink(s):TPS81256

(TOP VIEW) SIP-9 (BOTTOM VIEW) C2VIN GND GND VOUT VOUT VOUT C2VOUT VOUT VOUT VINC1 GND GND B1B3 EN EN TPS81256 SLVSAZ9 –JUNE 2012 www.ti.com ELECTRICAL CHARACTERISTICS (continued) Minimum and maximum valuesareatVIN = 2.5Vto5.5V,VOUT = 5.0V(orVIN,whicheverishigher),EN = 1.8V,TA = –40°C to 85°C; CircuitofParameterMeasurement Informationsection(unlessotherwisenoted).TypicalvaluesareatVIN = 3.6V,VOUT = 5.0V,EN = 1.8V,TA = 25°C (unlessotherwisenoted). PARAMETER TEST CONDITIONS MIN TYP MAX UNIT OSCILLATOR fOSC Oscillatorfrequency TPS81256 VIN = 3.6V,VOUT = 5.0V,IOUT = 500mA 4 MHz TIMING IOUT = 0mATPS8125x 70 µsTime fromactiveEN tostartswitching Start-uptime IOUT = 0mATPS81256 400 µsTime fromactiveEN toVOUT PIN ASSIGNMENTS (TPS8125X) Table1. TERMINAL FUNCTIONS TERMINAL I/O DESCRIPTION NAME NO. Thisistheenablepinofthedevice.Connectingthispintogroundforcesthedeviceintoshutdown EN B2 I mode. Pullingthispinhighenablesthedevice.Thispinmust notbe leftfloatingand must be terminated. GND A1,A2,B1 Ground pin. VIN C1, C2 I Power supplyinput. VOUT A3,B3,C3 O Boostconverteroutput.

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L VIN EN VOUT GND L VIN VOUT DC/DC Converter TPS8125X ENABLE GND CEXTCI Co L GND EN VIN C 2.2µF I 1µH C 2.2µF O VOUT DC/DC CONVERTER Undervoltage Lockout Thermal Shutdown Softstart Control Logic Gate Driver PMOS Valley Current Sense Error Amplifier VREF NMOS Modulator TPS81256 www.ti.com SLVSAZ9 –JUNE 2012 FUNCTIONAL BLOCK DIAGRAM PARAMETER MEASUREMENT INFORMATION Table2.ListofComponents REFERENCE DESCRIPTION PART NUMBER, MANUFACTURER C EXT 4.7μF,16V,0603,X5R ceramic GRM188R61C475KAAJ, muRata Copyright© 2012,Texas InstrumentsIncorporated SubmitDocumentationFeedback 5 ProductFolderLink(s):TPS81256

0.1 1 10 100 1000 I - Output Current - mAO 100 Efficiency - % V = 4.5 VI V = 4.2 VI V = 3.6 VI V = 2.7 VI V = 2.9 VI V = 3.3I V = 5 V, PFM/PWM Operation O Efficiency - % 100 V - Input Voltage - VI I = 100 mAO I = 500 mAO I = 1 mAO I = 10 mAO V = 5 V, PFM/PWM Operation O I = 300 mAO TPS81256 SLVSAZ9 –JUNE 2012 www.ti.com TYPICAL CHARACTERISTICS TABLE OF GRAPHS FIGURE vs Outputcurrent 3,5 η Efficiency vs Inputvoltage 4 vs Outputcurrent 6,7,8 VO DC outputvoltage vs Inputvoltage 9 IO Maximum outputcurrent vs Inputvoltage 10 ΔVO Peak-to-peakoutputripplevoltage vs Outputcurrent 11 ICC Supplycurrent vs Inputvoltage 12 ILIM Inputcurrent vs Outputcurrent 13 AC loadtransientresponse 14 Load transientresponse 15,16,17 Combined line/loadtransientresponse 18 Overloadrecoveryresponse 19 Start-up 20 EFFICIENCY EFFICIENCY vs vs OUTPUT CURRENT INPUT VOLTAGE Figure3. Figure4.

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200 300 400 500 600 700 800 900 1000 1100 I - Output Current - mAO 4.75 4.8 4.85 4.9 4.95 5.05 V - DC Output Voltage - V O V = 4.5 VI V = 3.6 VI V = 3.3 VI V = 5 V, PWM Operation O V = 2.7 VI V = 2.9 VI V = 3.2 VI V = 4.2 VI 0.1 1 10 100 1000 I - Output Current - mAO V = 5 V, PFM/PWM Operation O V - DC Output Voltage - V O 4.95 4.97 4.99 5.01 5.03 5.05 V = 3.6 V, T = 85°CI A V = 3.2 V, T = 85°CI A V = 4.3 V, T = 85°C I A V = 3.6 V, T = 25°CI A V = 3.2 V, T = 25°CI A V = 4.3 V, T = 25°C I A V = 3.6 V, T = -40°CI A V = 4.3 V, T = -40°CI A V = 3.2 V, T = -40°CI A 0.1 1 10 100 1000 I - Output Current - mAO Efficiency - % 100 T = -40°CA T = 25°CA T = 85°CA V = 3.6 V,I V = 5 V, PFM/PWM Operation O 0.1 1 10 100 1000 I - Output Current - mAO 4.95 5.05 5.1 5.15 V - DC Output Voltage - V O V = 5.1 VI V = 5 V, PFM/PWM Operation O V = 4.5 VI V = 3.6 VI V = 2.7 VI TPS81256 www.ti.com SLVSAZ9 –JUNE 2012 EFFICIENCY DC OUTPUT VOLTAGE vs vs OUTPUT CURRENT OUTPUT CURRENT Figure5. Figure6. DC OUTPUT VOLTAGE DC OUTPUT VOLTAGE vs vs OUTPUT CURRENT OUTPUT CURRENT Figure7. Figure8. Copyright© 2012,Texas InstrumentsIncorporated SubmitDocumentationFeedback 7 ProductFolderLink(s):TPS81256

0 100 200 300 400 500 600 700 V - Peak-to-Peak Output Ripple Voltage - mV O V = 2.7 VI V = 4.2 VI V = 3.6 VI V = 3.3 VI V = 5 V, PFM/PWM Operation O V - Input Voltage - VI Supply Current - A /c109 V = 5 V, I = 0 mA O O T = 85°CA T = 25°CA T = -40°CA V - Input Voltage - VI 4.95 5.05 5.1 5.15 5.2 5.25 5.3 5.35 5.4 5.45 5.5 5.55 V - DC Output Voltage - V O I = 500 mAO I = 100 mAO I = 10 mAO V = 5 V, PFM/PWM Operation O V = 5 V, PWM Operation O V - Input Voltage - VI 200 300 400 500 600 700 800 900 1000 1100 1200 I - Maximum Output Current - mAO T = -40°CA T = 25°CA T = 85°CA TPS81256 SLVSAZ9 –JUNE 2012 www.ti.com DC OUTPUT VOLTAGE MAXIMUM OUTPUT CURRENT vs vs INPUT VOLTAGE INPUT VOLTAGE Figure9. Figure10. PEAK-TO-PEAK OUTPUT RIPPLE VOLTAGE SUPPLY CURRENT vs vs OUTPUT CURRENT INPUT VOLTAGE Figure11. Figure12.

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V = 3.6 V, V = 5.0 V I O 40 to 400 mA Load Step V = 2.7 V, V = 5.0 V I O 40 to 400 mA Load Step 0 100 200 300 400 500 600 700 800 900 1000 V = 5 V, PFM/PWM Operation O 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.1 1.2 1.3 I - Input Current - mAIN V = 2.6 VI V = 4.5 VI V = 3.6 VI V = 3.3 VI V = 3 VI V = 4.2 VI 0 to 500mA Load Sweep V = 3.6 V, V = 5.0 V I O TPS81256 www.ti.com SLVSAZ9 –JUNE 2012 INPUT CURRENT vs OUTPUT CURRENT AC LOAD TRANSIENT Figure13. Figure14. LOAD TRANSIENT RESPONSE IN LOAD TRANSIENT RESPONSE IN PFM/PWM OPERATION PFM/PWM OPERATION Figure15. Figure16. Copyright© 2012,Texas InstrumentsIncorporated SubmitDocumentationFeedback 9 ProductFolderLink(s):TPS81256

V = 3.6 V, V = 5.0 V I O Load Sweep, up to 830mA 670mA 830mA V = 5.0 V, I O O = 0 mA V = 2.7 VI V = 3.6 VI V = 4.5 VI V = 4.5 V, V = 5.0 V I O 40 to 400 mA Load Step 3.2V to 3.8V Line Step V = 5.0 VO 40mA to 400mA Load Step TPS81256 SLVSAZ9 –JUNE 2012 www.ti.com LOAD TRANSIENT RESPONSE IN PFM/PWM OPERATION COMBINED LINE/LOAD TRANSIENT RESPONSE Figure17. Figure18. OVERLOAD RECOVERY RESPONSE START-UP Figure19. Figure20.

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www.ti.com SLVSAZ9 –JUNE 2012 DETAILED DESCRIPTION OPERATION The TPS8125x isa stand-alone,synchronous,step-upconverter.The converteroperatesata quasi-constant4- MHz frequencypulsewidthmodulation(PWM) at moderate to heavy loadcurrents.At lightloadcurrents,the TPS8125x converteroperatesinpower-savemode withpulsefrequencymodulation(PFM). DuringPWM operation,theconverteruses a novelquasi-constanton-timevalleycurrentmode controlscheme to achieveexcellentline/loadregulationand allowstheuse ofa smallceramicinductorand capacitors.Based on theVIN/VOUT ratio,a simplecircuitpredictstherequiredon-time. At thebeginningoftheswitchingcycle,thelow-sideN-MOS switchisturned-onand theinductorcurrentramps up toa peak currentthatisdefinedby theon-timeand theinductance.Inthesecond phase,once theon-timer has expired,therectifieristurned-onand theinductorcurrentdecays toa presetvalleycurrentthreshold.Finally, theswitchingcyclerepeatsby settingtheon timeragainand activatingthelow-sideN-MOS switch. Ingeneral,a dc/dcstep-upconvertercan onlyoperatein"true"boostmode, i.e.theoutput“boosted”by a certain amount above theinputvoltage.The TPS8125x deviceoperatesdifferentlyas itcan smoothlytransitioninand outofzerodutycycleoperation.Thereforetheoutputcan be keptas closeas possibletoitsregulationlimits even thoughtheconverterissubjecttoan inputvoltagethattendstobe excessive.Inthisoperationmode, the outputcurrentcapabilityoftheregulatorislimitedtoca.150mA. Refertothetypicalcharacteristicssection(DC OutputVoltagevs.InputVoltage)forfurtherdetails. The currentmode architecturewithadaptiveslopecompensationprovidesexcellenttransientload response whilerequiringonlyone externaltinycapacitorforoutputfilteringand loopstabilitypurposes.Internalsoft-start and loopcompensationsimplifiestheapplicationdesignprocess. POWER-SAVE MODE The TPS8125X integratesa power-savemode to improve efficiencyat lightload.In power save mode the converteronlyoperateswhen theoutputvoltagetripsbelowa setthresholdvoltage. Itramps up the outputvoltagewithseveralpulsesand goes intopower save mode once the outputvoltage exceedsthesetthresholdvoltage. The PFM mode isleftand PWM mode enteredincase theoutputcurrentcan notlongerbe supportedinPFM mode. Copyright© 2012,Texas InstrumentsIncorporated SubmitDocumentationFeedback 11 ProductFolderLink(s):TPS81256

/c104/c103 /c103OUT OUT(DC) IN(CL) IN VI = I V TPS81256 SLVSAZ9 –JUNE 2012 www.ti.com CURRENT LIMITOPERATION, MAXIMUM OUTPUT CURRENT The TPS8125x directlyand accuratelycontrolsthe average inputcurrentthroughintelligentadjustmentof the valleycurrentlimit.The currentlimitcircuitemploys a valleycurrentsensingscheme. Currentlimitdetection occursduringtheoff-timeby sensingofthevoltagedropacrossthesynchronousrectifier. The outputvoltageisreduced as the power stage of the deviceoperatesin a constantcurrentmode. The maximum continuousoutputcurrent(IOUT(CL) ),beforeenteringcurrentlimit(CL) operation,can be definedby Equation1. (1) The outputcurrent,IOUT(DC) , isthe average of the rectifierripplecurrentwaveform.When the loadcurrentis increasedsuch thatthe lowerpeak isabove the currentlimitthreshold,the off-timeisincreasedto allowthe currenttodecreasetothisthresholdbeforethenexton-timebegins(socalledfrequencyfold-backmechanism). When thecurrentlimitisreachedtheoutputvoltagedecreasesduringfurtherloadincrease. SOFTSTART, ENABLE The TPS8125x devicestartsoperationwhen EN issethighand startsup withthesoft-startsequence.Forproper operation,theEN pinmust be terminatedand must notbe leftfloating. The TPS8125x devicehas an internalsoftstartcircuitthatlimitstheinrushcurrentduringstart-up.The firststep inthestart-upcycleisthepre-chargephase.Duringpre-charge,therectifyingswitchisturnedon untiltheoutput capacitorischargedtoa valueclosetotheinputvoltage.The rectifyingswitchiscurrentlimited(approx.200mA) duringthisphase.Thismechanism isused tolimittheoutputcurrentundershort-circuitcondition. Once the outputcapacitorhas been biasedto the inputvoltage,the converterstartsswitching.The soft-start system progressivelyincreasesthe on-timeas a functionof the input-to-outputvoltageratio.As soon as the outputvoltageisreached,theregulationlooptakescontroland fullcurrentoperationispermitted. PullingtheEN pinlow forcesthedeviceinshutdown,witha shutdown currentoftypically1µA. Inthismode, true loaddisconnectbetween the batteryand loadpreventscurrentflowfrom VIN to VOUT , as wellas reverseflow fromVOUT toVIN. LOAD DISCONNECT AND REVERSE CURRENT PROTECTION Regularboostconvertersdo notdisconnecttheloadfromtheinputsupplyand thereforea connectedbatterywill be dischargeduringshutdown.The advantageof TPS8125x isthatthisconverterisdisconnectingthe output from theinputofthepower supplywhen itisdisabled(socalledtrueshutdown mode). Incase ofa connected batteryitpreventsitfrombeingdischargeduringshutdownoftheconverter. UNDERVOLTAGE LOCKOUT The under voltagelockoutcircuitpreventsthedevicefrom malfunctioningatlow inputvoltagesand thebattery fromexcessivedischarge.Itdisablestheoutputstageoftheconverteronce thefallingVIN tripstheunder-voltage lockoutthresholdVUVLO which istypically2.0V.The devicestartsoperationonce the risingVIN tripsVUVLO thresholdplusitshysteresisof100 mV attyp.2.1V. THERMAL REGULATION The TPS8125x devicecontainsa thermalregulationloopthatmonitorsthedietemperatureduringthepre-charge phase.Ifthedietemperaturerisestohighvaluesofabout110 °C, thedeviceautomaticallyreducesthecurrent topreventthedietemperaturefrom increasingfurther.Once thedietemperaturedropsabout10 °C below the threshold,thedevicewillautomaticallyincreasethecurrenttothetargetvalue.Thisfunctionalsoreducesthe currentduringa short-circuitcondition. THERMAL SHUTDOWN As soon as thejunctiontemperature,TJ,exceeds 140°C (typ.)thedevicegoes intothermalshutdown.Inthis mode, the high-sideand low-sideMOSFETs are turned-off.When the junctiontemperaturefallsbelow the thermalshutdownminus itshysteresis,thedevicecontinuoustheoperation.

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ESR OUT ESRV I R/c61 /c103 /c40 /c41 /c45 /c68 /c61 /c103 /c103 /c103 OUT OUT IN OUT I V VV C V f TPS81256 www.ti.com SLVSAZ9 –JUNE 2012

APPLICATION INFORMATION

Because ofthepulsatingoutputcurrentnatureoftheboostconverter,a low ESR outputcapacitorisrequiredto maintaincontrolloopstability,toenhance theconverter'stransientresponseand toreducetheoutputvoltage ripple.For theoutputcapacitor,itisrecommended touse smallceramiccapacitorsplacedas closeas possible totheVOUT and GND pinsoftheIC.The minimum capacitanceis2μF. To getan estimateofthesteadyrippledue tochargingand dischargingtheoutputcapacitance,Equation2 can be used. (2) Where fistheswitchingfrequencywhich is4MHz (typ.)and C istheeffectiveoutputcapacitance.Noticethe TPS8125x devicealreadyincorporatesca.1.2μF effectiveoutputcapacitance. In practice,the totalrippleislargerdue to the ESR of the outputcapacitor.Thisadditionalcomponent of the ripplecan be calculatedusingEquation3 (3) An MLCC capacitorwithtwicethevalueofthecalculatedminimum shouldbe used due toDC biaseffects.The outputcapacitorrequireseitheran X7R or X5R dielectric.Y5V and Z5U dielectriccapacitors,asidefrom their wide variationincapacitanceover temperature,become resistiveat highfrequencies.There are no additional requirementsregardingminimum ESR. Largercapacitorscause loweroutputvoltagerippleas wellas lower outputvoltagedropduringloadtransientsbutthetotaloutputcapacitancevalueshouldnotexceed ca.30µF. DC biaseffect:high cap. ceramiccapacitorsexhibitDC biaseffects,which have a stronginfluenceon the device'seffectivecapacitance.Thereforetherightcapacitorvaluehas tobe chosen verycarefully.Package size and voltageratingincombinationwithmaterialareresponsiblefordifferencesbetween theratedcapacitorvalue and it'seffectivecapacitance.For instance,a 4.7µF X5R 16V 0603 MLCC capacitorwould typicallyshow an effectivecapacitanceoflessthan2.5µF (under5V biascondition,hightemperatureand ageingeffects). Because thedamping factorintheoutputpathisdirectlyrelatedtoseveralresistiveparameters(e.g.inductor DCR, power-stagerDS(on), PWB DC resistance,loadswitchesrDS(on) … ) thatare temperaturedependant,the convertersmalland largesignalbehaviormust be checked overtheinputvoltagerange,loadcurrentrangeand temperaturerange. The easiestsanitytestistoevaluate,directlyattheconverter’s output,thefollowingaspects:

• PFM/PWM efficiency
• PFM/PWM and PWM loadtransientresponse Duringtherecoverytimefroma loadtransient,theoutputvoltagecan be monitoredforsettlingtime,overshootor ringingthathelpsjudgetheconverter’s stability.Withoutany ringing,theloophas usuallymore than45° ofphase margin. Copyright© 2012,Texas InstrumentsIncorporated SubmitDocumentationFeedback 13 ProductFolderLink(s):TPS81256

SLVSAZ9 –JUNE 2012 www.ti.com INPUT CAPACITOR Ina dc/dcboostconverter,sincetheinputcurrentiscontinuous,onlyminimum inputcapacitorisrequired.The TPS8125x deviceintegratesa low ESR decouplingcapacitortopreventlargevoltagetransientsthatcan cause misbehaviorofthedeviceorinterferenceinothercircuitsinthesystem. For most applications,the inputcapacitorthatis integratedintothe TPS8125x should be sufficient.Ifthe applicationexhibitsa noisyorerraticswitchingfrequency,experimentwithadditionalinputcapacitancetofinda remedy.Multilayerceramiccapacitorsare an excellentchoiceforinputdecouplingofthestep-upconverteras theyhave extremelylow ESR and areavailableinsmallfootprints.Additionalinputcapacitorsshouldbe located as closeas possibletothedevice. The TPS8125x uses a tinyceramicinputcapacitor.When a ceramiccapacitoriscombined withtraceor cable inductance,such as froma walladapter,a loadstepattheoutputcan induceringingattheVIN pin.Thisringing can coupletotheoutputand be mistakenas loopinstabilityorcan even damage thepart.Inthiscircumstance, additional"bulk"capacitance,such as electrolyticor tantalum,should be placed between the inputof the converterand the power sourceleadto reduce ringingthatcan occurbetween the inductanceof the power sourceleadsand C I.

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PACK– PACK+ CCSOUTSCL SDA CSOUT CSIN PGND SW STAT VREF PMID VBUS VBUS = +5V CIN BOOT OTG CD RSNS CCSIN VBAT

1 F/c109

4.7 F/c109

L 1.0 HO /c109 CO

10 F/c109

0.1 F/c109

47 F/c109

3.0 V .. 4.35 V TPS81256SIP ENABLE GND L VIN EN VOUT GND L DC/DC Converter 4.7µF 16V X5R (0603) 5V, 500mA USB-DCP Port VUSB

5.0 V, up to 550mA

4.7µF CI CO L VIN EN VOUT GND L VIN 3.3 V .. 4.8 V DC/DC Converter TPS81256SIP EN DC/DC GND The capacitor is not only required to decouple the audio power amplifier, but is also required to stable operation of the SMPS converter. The SMPS converter should be located in the close vicinity of the audio power amplifier. (1) CDECOUPLING (1) TPS81256 www.ti.com SLVSAZ9 –JUNE 2012 TYPICAL APPLICATIONS Figure21. "Boosted" Audio Power Supply Figure22. BatteryPowered USB-DCP Power Supply Copyright© 2012,Texas InstrumentsIncorporated SubmitDocumentationFeedback 15 ProductFolderLink(s):TPS81256

Copper Trace ThicknessSolder Mask Thickness M0200-01 TPS81256 SLVSAZ9 –JUNE 2012 www.ti.com LAYOUT CONSIDERATION Inmaking thepad sizefortheSiP LGA balls,itisrecommended thatthelayoutuse non-solder-maskdefined (NSMD) land.With thismethod, the soldermask openingismade largerthan the desiredlandarea,and the openingsizeisdefinedby thecopperpad width.Figure23 shows theappropriatediametersfora MicroSiPTM layout. Figure23. Recommended Land PatternImage and Dimensions SOLDER PAD SOLDER MASK (5) COPPER STENCIL (6) COPPER PAD STENCIL THICKNESSDEFINITIONS (1)(2)(3)(4) OPENING THICKNESS OPENING (1) Circuittracesfromnon-solder-maskdefinedPWB landsshouldbe 75μm to100μm wideintheexposed areainsidethesoldermask opening.Widertracewidthsreducedevicestandoffand affectreliability. (2) Bestreliabilityresultsareachievedwhen thePWB laminateglasstransitiontemperatureisabove theoperatingtherangeofthe intendedapplication. (3) Recommend solderpasteisType 3 orType 4. (4) Fora PWB usinga Ni/Ausurfacefinish,thegoldthicknessshouldbe lessthan0.5mm toavoida reductioninthermalfatigue performance. (5) Soldermask thicknessshouldbe lessthan20 μm on topofthecoppercircuitpattern. (6) Forbestsolderstencilperformanceuse lasercutstencilswithelectropolishing.Chemicallyetchedstencilsgiveinferiorsolderpaste volume control. SURFACE MOUNT INFORMATION The TPS8125x MicroSiP™ DC/DC converteruses an open frame constructionthatis designed fora fully automatedassemblyprocessand thatfeaturesa largesurfaceareaforpickand placeoperations.See the"Pick Area"inthepackage drawings. Package heightand weighthave been kepttoa minimum therebytoallowtheMicroSiP™ devicetobe handled similarlytoa 0805 component. See JEDEC/IPC standardJ-STD-20bforreflowrecommendations.

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www.ti.com SLVSAZ9 –JUNE 2012 THERMAL AND RELIABILITY INFORMATION The TPS8125x outputcurrentmay need tobe de-ratedifitisrequiredtooperateina highambienttemperature or delivera largeamount of continuouspower.The amount of currentde-ratingisdependent upon the input voltage,outputpower and environmentalthermalconditions.Care shouldespeciallybe takeninapplications where thelocalizedPWB temperatureexceeds65°C. The TPS8125x dieand inductortemperatureshouldbe keptlowerthanthemaximum ratingof125°C, so care shouldbe takeninthecircuitlayouttoensuregood heatsinking.Sufficientcoolingshouldbe providedtoensure reliableoperation. To estimatethejunctiontemperature,approximatethepower dissipationwithintheTPS8125x by applyingthe typicalefficiencystatedinthisdatasheettothedesiredoutputpower;or,by takinga power measurement ifyou have an actualTPS8125x device or a TPS8125XEVM evaluationmodule. Then calculatethe internal temperatureriseof the TPS8125x above the surfaceof the printedcircuitboard by multiplyingthe TPS8125x power dissipationby thethermalresistance. The thermalresistancenumbers listedintheThermal Informationtableare based on modelingtheMicroSiP™ package mounted on a high-Ktestboard specifiedper JEDEC standard.For increasedaccuracyand fidelityto theactualapplication,itisrecommended torun a thermalimage analysisoftheactualsystem.Figure24 and Figure25 arethermalimages ofTI’s evaluationboardwithreadingsofthetemperaturesatspecific locationson thedevice. Figure24.VIN=3.6V,VOUT =5V, IOUT =300mA Figure25.VIN=3.6V,VOUT =5V, IOUT =600mA 150mW Power DissipationatRoom Temp. 600mW Power DissipationatRoom Temp. The TPS8125x is equipped with a thermal shutdown that willinhibitpower switchingat high junction temperatures.The activationthresholdofthisfunction,however,isabove 125°C toavoidinterferingwithnormal operation.Thus,itfollowsthatprolongedorrepetitiveoperationundera conditioninwhichthethermalshutdown activatesnecessarilymeans thatthe components internalto the MicroSiP™ package are subjectedto high temperaturesforprolongedorrepetitiveintervals,whichmay damage orimpairthereliabilityofthedevice. MLCC capacitorreliability/lifetimeis depending on temperatureand appliedvoltageconditions.At higher temperatures,MLCC capacitorsaresubjecttostrongerstress.On thebasisoffrequentlyevaluatedfailurerates determinedatstandardizedtestconditions,thereliabilityofallMLCC capacitorscan be calculatedfortheiractual operatingtemperatureand voltage. Copyright© 2012,Texas InstrumentsIncorporated SubmitDocumentationFeedback 17 ProductFolderLink(s):TPS81256

E TOP VIEW BOTTOM VIEW YML LSB CC 0.01 0.1 100 1000 10000 20 40 60 80 100 120 140 Capacitor Case Temperature ( °C) Time (Thousand Hours) VBias=5V VBias=4.35V VBias=3.6V VBias=3V G000 0.1 100 1000 10000 100000 20 40 60 80 100 120 140 Capacitor Case Temperature ( °C) Time (Thousand Hours) VBias=5V VBias=4.35V VBias=3.6V VBias=3V G000 TPS81256 SLVSAZ9 –JUNE 2012 www.ti.com CapacitorLifetime CapacitorB1 Lifetime vs vs CapacitorCase Temperature CapacitorCase Temperature Figure26. Figure27. Failurescaused by systematicdegradationcan be describedby the Arrheniusmodel. The most critical isused as thefailurecriterion,see Figure26.Figure27 (B1 life)definesthecapacitorlifetimebased on a failure ratereaching1%. Itshouldbe notedthatthewear-outmechanisms occurringintheMLCC capacitorsare not reversiblebutcumulativeovertime. PACKAGE SUMMARY SIP PACKAGE Code:

• CC — Package markingChipCode (seeformore details)
• YML — Y:Year,M: Month,L:Lottracecode
• LSB — L:Lottracecode,S:Sitecode,B:Board locator MicroSiPTM DC/DC MODULE PACKAGE DIMENSIONS The TPS8125x deviceisavailableinan 8-bump ballgridarray(BGA) package.The package dimensionsare:
• D = 2.575±0.05mm
• E = 2.925±0.05mm

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www.ti.com 16-Jul-2012 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) Samples (Requires Login) TPS81256SIPR ACTIVE uSiP SIP 9 3000 Green (RoHS & no Sb/Br) Call TI Level-2-260C-1 YEAR TPS81256SIPT ACTIVE uSiP SIP 9 250 Green (RoHS & no Sb/Br) Call TI Level-2-260C-1 YEAR (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. 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 PACKAGE MATERIALS INFORMATION www.ti.com 19-Jul-2012 Pack Materials-Page 1

*All dimensions are nominal Device Package Type Package Drawing Pins SPQ Length (mm) Width (mm) Height (mm) TPS81256SIPR uSiP SIP 9 3000 223.0 194.0 35.0 PACKAGE MATERIALS INFORMATION www.ti.com 19-Jul-2012 Pack Materials-Page 2

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