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SNOSB76C –December 2010–RevisedMay 2013 AN-2121 SolarMagic™ SM3320-BATT-EV Charge ControllerReferenceDesign ABSTRACT The SM72442 MPPT digitalcontrollerand SM72295 photovoltaicfullbridgedriversaredesignedtocontrol high-efficiencyDC/DC conversionused in photovoltaicapplications.This applicationreportdetailsthe usage ofthosedevicesina batterychargingapplication.The referencedesignismeant toprovidesupport fora wide varietyofimplementations,however,unlessotherwisenoted,thisreferencedesignsystem is shown charginga 12V commercialautomotiveleadacidbattery.

Contents

SolarMagicisa trademarkofTexas Instruments. Allothertrademarksarethepropertyoftheirrespectiveowners. 1SNOSB76C –December 2010–RevisedMay 2013 AN-2121 SolarMagic™ SM3320-BATT-EV Charge ControllerReference DesignSubmitDocumentationFeedback Copyright© 2010–2013,Texas InstrumentsIncorporated

www.ti.com

2 AN-2121 SolarMagic™ SM3320-BATT-EV Charge ControllerReference SNOSB76C –December 2010–RevisedMay 2013

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1 Charging Profile

Figure1 shows thelead-acidchargingprofileused inthisreferencedesign. Ifthebatteryvoltageisverylow,a slowchargecurrentisappliedand limiteduntilthevoltagerisesabove a pre-setthresholdvalueVt.The fullchargecurrentisthenapplied.Once fullchargeisdetectedon the voltageofthebattery,thesystemswitchestoa floatingchargeand maintainsthebatteryvoltageata fixed threshold.Atany time,thesystemwillruninMPPT mode iftheavailablepower islowerthanthepower requiredtoachievevoltageorcurrentregulation. Figure1.Lead-AcidCharging Profile

2 Features

  • 12V Lead AcidBattery
  • Vinrange= 15V to45V Vmp (50V Voc)
  • Max InputCurrent:Isc= 11A
  • MPPT algorithmforoptimizedphotovoltaicapplications
  • Up to9A chargingcurrent
  • Reversecurrentprotection
  • Tricklechargeand fastchargemode
  • Up to98% converterefficiency
  • 14.2Vmax chargevoltage,13.5Vfloatingvoltage
  • Outputvoltageset-pointscan be reprogrammed 3SNOSB76C –December 2010–RevisedMay 2013 AN-2121 SolarMagic™ SM3320-BATT-EV Charge ControllerReference DesignSubmitDocumentationFeedback Copyright© 2010–2013,Texas InstrumentsIncorporated

QuickSetupProcedure www.ti.com

3 Quick Setup Procedure

Step 1:Verifylead-acidbatteryvoltagelessthan12V,higherthan10V. Step 2:Connectbatterytooutputterminalsas shown inFigure2. Step 3:ConnectSolarpanelorSolarArraySimulatortotheinputterminalsas shown inFigure2. Step 4:Verifybatterychargingcurrentup to9A (Averageslightlyunder9A). Step 5:Ifbatterycurrentlow,verifyinputoperatesatmaximum power pointvoltageas specifiedby the panelmanufacturer. Step 6:Verifychargingprofilefollowstheprofileshown inFigure1. Figure2.System Connection 4 10V Power Supply The circuitshown inFigure3 willprovidea 10V power supplyrailrequiredtoproperlybiastheSM72295 gatedriver.The systemcan be configuredtowork withsolarpanelsup to100V(withpropercomponents sizing)and down to12V Vmp. Figure3.10V Power Supply

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www.ti.com DC/DC Converter

5 DC/DC Converter

The DC/DC converterstageisa stepup/stepdown fourswitchconverteras shown inFigure4.Thisstage transfersthepower fromthePV paneltotheload. Figure4.DC/DC ConverterStage C18, R11, and D15 as shown inthesystemschematicinFigure20,forma snubbertoreducerippleon theswitchnode on the“Buck”sideoftheconverter.C19,R14 and D14 forma snubbercircuittoreduce rippleon theswitchnode ofthe“Boost”sideoftheconverter. When thecircuitoperatesinBuck mode, theBoostswitchnode willissuesmallpulsesata lower frequencyinordertorechargetheBootstrapcapacitorofQ2. Likewise,inBoostmode, theBuck switch node willpulsetorechargethebootstrapcapacitorofQ1. SpecificdesignguidelinesfortheDC/DC convertercan be foundintheAN-2124 Power CircuitDesignfor SolarMagicSM3320 ApplicationReport(SNOSB84 )forpower optimizers. Specifictimingsrelatedtotheswitchescan be foundinSM72442 Programmable Maximum Power Point TrackingControllerforPhotovoltaicSolarPanels(SNVS689 )and SM72295 PhotovoltaicFullBridgeDriver (SNVS688 ). The waveformsinFigure5 throughFigure8 areexamplesoftheswitchingsignalsoftheDC/DC converter stage. Ifthesystemistobe used atelevatedpower levelscausinghightemperatureincreasesinMOSFETs Q1, Q2, Q3, and/orQ4, we recommend theuse ofa properheatsinkfortheMOSFETs, especiallyathigher ambienttemperatures.Care must be takentopreventelectricalcontactbetween thedrainsofthe MOSFETs intheprocessofproperheatsinking. Figure5.Buck Gate DriveSignalsFrom SM72442 Figure6.Switch Nodes inBuck Mode 5SNOSB76C –December 2010–RevisedMay 2013 AN-2121 SolarMagic™ SM3320-BATT-EV Charge ControllerReference DesignSubmitDocumentationFeedback Copyright© 2010–2013,Texas InstrumentsIncorporated

Programmable Modes/GainSettings www.ti.com Figure7.Boost Gate DriveSignalsFrom SM72442 Figure8.Switch Nodes inBoost Mode

6 Programmable Modes/Gain Settings

The voltagedividersfortheoutputvoltagesensingaresettoensurehighresolutionoftheoutputvoltage whileprovidinga safevoltage(<5V) fortheSM72442 and microcontroller. The defaultresistorsettinginthisreferencedesignsetsa fullscaleof30V. The programmablemodes oftheSM72442 used inthisdesignareas follows:

  • VADC2 = 5V (50% of4sec inBB)
  • VADC6 = 5V (startupat0mA)
  • VADC0 = 0V.Thisvalueprovidesan initialoutputvoltagelimitof19V.However,thislimitwillbe modifiedby themicrocontrollerthroughI2C beforethecontrollerbeginssupplyingthebattery.
  • VADC4 = 5V.Currentlimitingwillbe done externallyso themax currentlimitcan be setatfullscale.

7 CurrentSense Gains and Offset

The gainofthecurrentsensingcircuitdepends on theapplication.Inoursystemitwas setwitha gainof 0.44V/Amps. The gainissetby a pull-downresistorattheoutputofIOUT (12)and IIN(3)pinsofthe SM72295 as statedinthedatasheetofthedevice.

6 AN-2121 SolarMagic™ SM3320-BATT-EV Charge ControllerReference SNOSB76C –December 2010–RevisedMay 2013

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www.ti.com Start-UpCircuitry

8 Start-UpCircuitry

Ifthepanelvoltageislowerthanthebatteryvoltage,a startup circuit(Figure9)isrequiredtoforcethe dutycyclehighenough tocreatea flowofcurrenttothebattery.Once currentisestablished,thecircuit can be turnedofftoallowMPPT operationtoperform. Figure9.Start-UpBoost Circuitry As longas thestart-upcircuitisactivated,thedutycyclewillincreaseevery1ms up toitsmaximum value. However,thedutycyclewillstillbe limitedby theSM72442 ’s internaloutputvoltagelimiter. The circuitisturnedon when theanode ofD101 and thecathodeofD100 arekeptat5V.Itisdisabled when thatnode issetat0V. The circuitshouldbe disabled5ms aftercurrentbeginstoflowintothebatterytoallowproperMPPT operation. Ifthecurrentdropsto0 forany reason(nolight,reset,and so on)thestart-upcircuitcan be re-engaged accordingtothetimingdiagraminFigure10. Thiscircuitoperatesby sensingtheaveragevalueofthegatevoltageon themain buck switch(Q1)and main boostswitch(Q4).Thisvalueisfedback totheinputcurrentsense oftheSM72442. Atthesame time,a constant4.4Vissetattheinputvoltagesense pinoftheSM72442. ThisresultsintheSM72442 measuringa virtualpower thatincreaseseach timethedutycycleisincreasedand decreaseseach time thedutycycleisdecreased.The SM72442 willtrackthisvirtualpower and increasethedutycycleofthe convertercontinuously.When thiscircuitisde-activated,therealinputvoltageand currentappearatthe sensingpinsoftheSM72442 chipwhichwillthenperformregularMPPT operation. 7SNOSB76C –December 2010–RevisedMay 2013 AN-2121 SolarMagic™ SM3320-BATT-EV Charge ControllerReference DesignSubmitDocumentationFeedback Copyright© 2010–2013,Texas InstrumentsIncorporated

OutputFET Disabling www.ti.com Figure10.Start-upCircuitTiming Diagram Figure11 shows theexpectedwaveform ifthepanelvoltageislessthanthebatteryvoltage.The panel Vmp forthisexample is12V @ 3A and thebatteryvoltageisat25V.Figure12 showcases themagnified versionofthebatterycurrentshown inFigure11. NOTE: To highlighttheboostingcapabilityofthesystemand start-upcircuit,theboardhas been re- configuredtorunwitha 24V batteryfortheexperimentsshown inFigure11 and Figure12. Figure11.Start-upVPanel < VBatt Figure12.Start-upDetailofBatteryCurrent

9 Output FET Disabling

Q9 keep thetopsideoutputFET Q2 fromturningon.The power willflowthroughtheparalleldiodeD7 instead.ThispreventsthebatteryfromdischargingintothePV panels.Q2 can be disabledusingthe microcontrollerora comparator(U12A)connectedtotheoutputcurrentsensing:when currentdrops belowthethresholdvalue,Q2 isdisabled.The thresholdissetto1A by default.

8 AN-2121 SolarMagic™ SM3320-BATT-EV Charge ControllerReference SNOSB76C –December 2010–RevisedMay 2013

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Vsetpoint = Reg3[29:20] 1024 x VDDA x R 51 + R52 + R53 R 53 www.ti.com OutputCurrentRegulation

10 Output CurrentRegulation

Currentregulationisenforcedby a comparator(U11A).The currentsettingcan be switchedfroma low currentlimittoa highcurrentlimitwitha bitsetby themicrocontroller.When microcontrollerpinRC5 (pin number 16)issettohighimpedance,thehighcurrentlimitisset.When pinRC5 issetto0V,thelow currentlimitisset. Inthisdesign,thehighcurrentlimitissetto9A and thelowcurrentlimitto0.5A.

11 VoltageRegulation

VoltageregulationwiththeSM72442 isperformedinternally.The initialoutputvoltagesettingisset throughpinA0 (0-5V).The outputvoltagesetpointcan thenbe changed throughtheI2C communication interfaceby settingtheregister0x03 bits20:29totherequiredvoltagesetpointand bit46 to1. Figure13 shows thesystemperformingvoltageregulationon thebatteryat13.5V. Inadditiontothevoltageregulation,a comparator(U11B)willresettheSM72442 and cause theDC/DC convertertoshutdowniftheoutputvoltageincreasesbeyond thevaluessetby R71 and R72. When the negativeinputofthecomparatorreachesover5V,theSM72442 controllerwillbe reset.The defaultvalue correspondsto14.6Vbatteryvoltage. (1) Figure13.Charging Waveforms During Float 9SNOSB76C –December 2010–RevisedMay 2013 AN-2121 SolarMagic™ SM3320-BATT-EV Charge ControllerReference DesignSubmitDocumentationFeedback Copyright© 2010–2013,Texas InstrumentsIncorporated

MPPT www.ti.com

12 MPPT

The SM72442 chipwillperformtheMPPT functionusingan implementationofthePerturband Observe algorithmmethod.The MPPT algorithmwillextractmaximum power fromthesolarpaneland deliveritto thebatteryregardlessofthepanel’s characteristics.Figure14 and Figure15 show theeffecton thepanel voltageas theMPPT algorithmmaintainsconstantpower atthepanelregardlessofthevoltageon the battery. Figure14.BatteryCharging with Figure15.BatteryCharging with VPanel < VBattery(Boost) VPanel > VBattery(Buck)

10 AN-2121 SolarMagic™ SM3320-BATT-EV Charge ControllerReference SNOSB76C –December 2010–RevisedMay 2013

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www.ti.com MicrocontrollerFunctions

13 MicrocontrollerFunctions

The chargeprofileisimplementedinthecurrentdesignusinga PIC16F722 microcontroller.

13.1 Normal Operation

The flowchartinFigure16 detailstheoperationofthemicrocontrollerneeded toachievethedesired chargingpattern. Modificationtothisflowchartcan easilybe done and programmed toinclude:

  • Modifiedthresholddependingon temperature(ifbatterytemperatureinformationavailable).
  • Timertomaintainhighvoltagethresholdfora certaintimebeforeswitchingtofloatingchargeto maximizeenergystoredinthebattery.
  • Pulsechargingduringthefloatchargeperiod. The microcontrollerisprogrammed usinga 10 pinCLE-105 connector(J5).The connectionsare:
  • 1:NC (NotConnected)
  • 2:PGD/ICSPDAT
  • 3:GND
  • 4:PGC/ICSPCLK
  • 5:NC
  • 6:GND
  • 7:+5Vdc
  • 8:MCLR!
  • 9:GND
  • 10:NC RefertotheMicrochipwebsiteforproperprogramming/debuggingofthePIC16F familymicrocontrollers.

13.2 Start-UpOperation

Atstart-up,themicrocontrollerneeds toassessthePV and batteryvoltagetoverifyproperconnectionand values. Ifthevaluesarewithinthespecifiedrange(correctpaneland batteryvoltage),themicrocontrollerenables thechargeby releasingtheRESET lineoftheSM72442 chip.Ifneeded,thestart-upcircuitisturnedon by settingRB5 to‘1’(5V)(Ifthemicrocontrollerused intheapplicationisrunningbelow5V,a levelshifting circuitwillbe necessary). Once currentbeginstoflowinthebatterythestart-upcircuitcan be released. Whilethestart-upcircuitisenabled,thepanelcurrentand voltagearenotavailablethroughI2C.The correspondingregisterscan be readbutwillnotcontainthecorrectvalues.

13.3 SafetyFeature

The microcontrollerisprogrammed by defaulttostopchargingthebatteryiftheoutputvoltageisabove 14.5Vorbelow8V. 11SNOSB76C –December 2010–RevisedMay 2013 AN-2121 SolarMagic™ SM3320-BATT-EV Charge ControllerReference DesignSubmitDocumentationFeedback Copyright© 2010–2013,Texas InstrumentsIncorporated

MicrocontrollerFunctions www.ti.com Figure16.Basic OperationalFlowchart

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14.3V Vbatt>14.5V? Vbatt<8V? Vbatt>14.2V? Set voltage to 13.5V Vbatt<10V? Set low current limit Set high current limit Defective battery or no batter Engage SM72442 Reset Wait Yes Yes No Yes Yes No No No www.ti.com MicrocontrollerProgram Code

14 MicrocontrollerProgram Code

The flowchartinFigure17 isrepresentativeofthecode programmed insidethemicrocontroller. The check_lead_acidfunctionissuesa valuedependingon thestateofthebatteryas detectedby the voltage.The main functionuses thisvaluetoissuetheproperaction.The otherfunctionsintheprogram areessentiallyI2C driverfunctionsand lowlevelportsetupfunctions. Figure17.MicrocontrollerCode Flowchart 13SNOSB76C –December 2010–RevisedMay 2013 AN-2121 SolarMagic™ SM3320-BATT-EV Charge ControllerReference DesignSubmitDocumentationFeedback Copyright© 2010–2013,Texas InstrumentsIncorporated

MicrocontrollerProgram Code www.ti.com

14.1 Function:check_lead_acid()

Thisfunctionsensesthebatteryvoltagethroughthemicrocontroller’s A/D converter.The A/D conversion isneeded because thecurrentlimitingcircuitinhardwareactson thevoltagesensinglineofthe SM72442. Therefore,when thesystemisrunninginhighcurrentmode, thevoltagesensed by the SM72442 isnotthebatteryvoltage.Ifthecurrentlimitationisnotnecessary,such as panelswithlimited power capabilities,thevoltageused by thecheck_lead_acid()functioncouldbe changed tothevalue recoveredfromtheSM72442 throughI2C insteadofusingthemicrocontroller’s ADC. Thisfunctionverifiesthestateofthebatteryby sensingitsvoltageand returnsan 8 bitnumber relatedto thestateofthebattery:

  • 0:No change
  • 1:BatteryreachedthefullStateOf Charge voltage
  • 2:Batteryvoltageislow
  • 3:Batteryvoltageistooloworbatterydamaged/disconnected
  • 4:Batteryvoltageisabove theacceptablevalue:batterydamaged ordisconnected
  • 5:Batteryvoltagehas reachedabove 13.6V.Thisisusuallydue tothelowerlimiton thedutycycleof thebuck converter.When thebatterystaysinfloatingchargestatefortoolong,theconverterwillkeep pumping a minimum currentintothebatterywhichcouldresultinan increaseofthebatteryvoltage beyond thedesiredfloatingchargevoltagerange.
  • 6:Batteryvoltagehas returnedtoan acceptablevalue States5 and 6 correspondtothestateofchargeofthebatteryafterithas reachedit'sfloatingcharge statevalueof13.5V.When “5”isreturnedby thisfunction,theprogramwillcompletelycutthechargeinto thebattery(byissuinga resettotheSM72442 viaPORTB ofthemicrocontroller).When “6”isreturnedby thisfunction,theprogramwillre-enablethefloatingchargeintothebatteryby releasingthereseton the SM72442.

14.2 Function:Main()

The “Main”functioncallsthe”Init()”function,whichsimplyinitializesthevariablesand theregisters.The programthenentersan infinitewhile-loopinwhichthevaluesofthesensed voltagesand currentare recoveredfromtheSM72442 throughI2C.The function“check_lead_acid()”iscalledand returnsa value based on thevoltageofthebattery.The “Main”functionuses thisvaluetomodifythebehaviorofthe system.The followingliststhevaluesreturnedfromthe“check_lead_acid()”functionthecorresponding actionthe“Main”functionwilltake:

  • 1 (fullychargedbattery):The floatingchargevoltagesetpointwillbe senttoSM72442 throughI2C
  • 2 (heavilydischargedbattery):Tricklechargewillbe applied
  • 3 (batteryvoltagetoolow):System shutsdown by keepingtheSM72442 inresetmode (bitRB2 set)
  • 4 (batteryvoltagetoohigh):System shutsdown by keepingtheSM72442 inresetmode (bitRB2 set)
  • 5 (batteryvoltageslightlyhighinfloatingcharge):System shutsdown by keepingtheSM72442 in resetmode (bitRB2 set)and hysteresisflagset
  • 6 (batteryvoltagedroppedbelow13V afterhysteresisflagset):Re-enableSM72442, hysteresisflag reset The Main functionalsoresetsthewatchdogtimeronce everyiterationofthewhile-loop.

14.3 Function:get_i2c_data

Thisfunctionreadsthesampled voltageofpinAIIN(19),AVIN(15),AIOUT(21),and AVOUT(17) ofthe SM72442. The dataisfetchedthroughtheI2C channel.The functionupdatestheglobalvariable“outval” whichisan arrayofunsigned16 bitintegers.The dataonlyoccupies10bitsofeach integer(full scale=1023).

  • outval[0]= inputcurrent
  • outval[1]= inputvoltage
  • outval[2]= outputcurrent
  • outval[3]= outputvoltage

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  • Call proper functions - Set Voltage Levels - Enable/disable SM72442 Check_Lead_Acid - Sense battery voltage - Return value of battery state Init() Setup registers Send_i2c_command Send the content of the communication buffer on the I2C bus Check_low_current Check if current is very low Get_i2c_data - Send request for data through I2C - Recover and parse data in global variable Set_Vout_max Setup I2C communication words to change the output voltage level controlled by the SM72442 www.ti.com Charginga Li-ionBattery

14.4 Function:send_i2c_command(char number)

Sends an I2C communicationstring.Each bytesentisstoredintheglobalarray“i2c_buffer”.The argument“number”indicateshow many bytesfromthebufferwillbe sent(startingwithi2c_buffer[0]). Refertothedatasheetand I2C and SM_bus standardsdocumentationforcompleteprotocolinformation. The main use ofthisfunctionistochange thevoltagelimitsettingsintheSM72442.

14.5 Function:Set_Voutmax()

Thiswillreadthe“voutmax”variablesetinthemain and sends theproperI2C command totheSM72442 toregulatethatvoltage.

14.6 Function:Check_low_current()

Thisfunctioniscalledby the“Main”functionand controlsthestart-upcircuitrytoforcethedutycycleof theconverterup ifthecurrentbecomes closeto0. Figure18 summarizestheoverallstructureoftheprogram:(arrowsfromthemain representcallstothe functions) Figure18.MicrocontrollerCode Block Diagram

15 Charging a Li-ionBattery

Althoughthisevaluationboardwas specificallydesignedforcharginga lead-acidbattery,itcan be re- configuredtoaccommodate theLi-ionchemistrybatterythrougha combinationofhardwareand software changes.Inordertore-configuretheboardforLi-ioncharging,thefollowingstepsneed tobe done: 1. The voltagesensingresistorsR103, R104, R51, R52 and R53 and OVP resistorsR71 and R72 need tobe changed tothepropervalues.Itiscriticalforthisapplicationthatthefullscalevoltagerangefor sensingisas closeas possibletothevoltageofthebatterytomaximizetheresolutionofthesensed voltage.The leveloftheOVP circuitneeds tobe scaledso thatitdoes nottriggerwhen thebattery approachesfullSOC butata voltageslightlyhigher. 15SNOSB76C –December 2010–RevisedMay 2013 AN-2121 SolarMagic™ SM3320-BATT-EV Charge ControllerReference DesignSubmitDocumentationFeedback Copyright© 2010–2013,Texas InstrumentsIncorporated

VHARD_OVP = VBAT x R 72 R 71 + R72 VAVOUT = VBAT x R 53 R 51 + R52 + R53 VA12 = VBAT x R 103 R 103 + R104 Charginga Li-ionBattery www.ti.com

  • R103 and R104 setthevoltageattheinputofthemicrocontroller.The voltageattheinputofthe microcontrolleris: (2)
  • R103 and R104 shouldbe chosen so thatthemaximum expectedbatteryvoltagecreatesa voltage closeto5V tomaximizeresolution(butlessthan5V toavoidsaturatingthemeasure).
  • R51, R52 and R53 areforthevoltagemeasurement oftheSM72442 and shouldbe modifiedinthe same way: (3)
  • R21 needs tobe settozeroohm (short).
  • Once thevaluesarepicked,theproperthresholdneeds tobe programmed throughI2C.The maximum level(0x3FF)isnow VAVOUT = 5V attheinputoftheSM72442.
  • Finally,theovervoltageprotectionshouldbe adjustedto: (4)
  • The OVP levelissetatVHARD_OVP = 5v. 2. The propervoltagesetpointsand chargingcurveneed tobe programmed inthemicrocontroller.The initialvoltagelimitissetby R28 and R38. VoltagelimitsetpointisAVOUT = A0.Once overridden throughI2C,thevoltageatA0 isnotused anymore.Hence,thereistheoptionofsettingthevalue throughresistorsR28 and R38 orby programmingitfromthemicrocontrollerintoSM72442 through I2C each timetheSM72442 isreset/powered. 3. Propercurrentlimitsalsoneed tobe setifrequiredby thebatterymodel.The currentlimitvalueisset when thevoltageatpin3 ofU11A equalsthevoltageatpin2.Hence,R111 and R112 willneed tobe adjustedaccordingly. 4. The softwareneeds tobe changed tofollowtheLi-ionchargecontrolprofile:batteryvoltageisset eitherby hardwareas statedabove,whichrequiresno actionfromthesoftware,oritissetfromthe microcontrollerthroughtheI2C interfacesimilartotheLead Acidbattery. 5. Finally,thesoftwareneeds toincludethefullState-Of-Chargecut-off:When thebatteryreachesitsfull voltageand currenthas droppedbelow500mA (canvarydependingon battery),chargeiscut-offand thebatteryisconsideredfullycharged(notricklechargeofLi-ionbatteriesshouldbe done).Itis importanttoremember thatcurrentcan dropbelow500mA duringthechargewhen solarpower becomes unavailable(lowlightintensity).Thereforethechargecut-offneeds tobe programmed to occuronlywhen thebatteryvoltageisatthelimitAND currenthas droppedbelowtherequired threshold. Figure19 shows thetypicalchargingprofilefora Li-ionbattery. Figure19.Li-ionCharge Profile

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www.ti.com BillofMaterials

16 BillofMaterials

Designator Description Manufacturer PartNumber Qty

1 U17 Flash-Based,8-BitCMOS Microcontroller,MicrochipTechnology PIC16F722-E/SS or 1

2K (x14-Bitwords)Program Memory, 128 PIC16F722-I/SS BytesData Memory, 25 I/Opins,28-Pin SOIC, StandardVDD Range, Extended Temperature 2 C1, C2, C3, C4, C5, Ceramic,X7R, 50V,10% MuRata C3225X7R1H225k/2.50 32 C6, C7, C8, C9, C10, C11, C12, C13, C14, C16, C20, C25, C27, C28, C30, C36, C42, C44, C45, C47, C48, C53, C55, C57, C67, C70, C72

3 C15, C17, C22, C26, Ceramic,X7R, 25V,10% MuRata GRM188R71E104KA01D 10

C32, C49, C50, C51, C52, C65

4 C18, C19 Ceramic,C0G/NP0, 100V,5% AVX 08051A471JAT2A 2

5 C21 Ceramic,X7R, 100V,10% TaiyoYuden HMK212B7104KG-T 1

6 C23, C33, C34, C38 Ceramic,X7R, 16V,10% TaiyoYuden EMK212B7225KG-T 4

7 C24 Ceramic,X7R, 50V,10% MuRata GRM188R71H331KA01D 1

8 C29, C37, C39, C59 Ceramic,X7R, 100V,20% AVX 06031C103MAT2A 4

9 C31, C35, C40 Ceramic,X7R, 16V,10% TaiyoYuden EMK212B7105KG-T 3

10 C46, C54 Ceramic,X7R, 16V,10% AVX 0805YC474KAT2A 2

11 C58, C60, C61, C62, Ceramic,C0G/NP0, 100V,5% TDK C1608C0G2A102J 6

C66, C69

12 C73 Ceramic,C0G/NP0, 50V,5% TDK C1608C0G1H151J 1

13 C88 CAP, CERM, 0.1uF,25V,+/-5%,X7R, AVX 06033C104JAT2A 1 0603

14 C100, C102 CAP, CERM, 1000pF,100V,+/-10%,X8R, TDK C1608X8R2A102K 2

15 C101 CAP, CERM, 0.1uF,16V,+/-5%,X7R, AVX 0603YC104JAT2A 1 0603 16 D2, D7, D9, D12, D13, Vr = 100V,Io= 1A,Vf= 0.77V DiodesInc. DFLS1100-7 7 D14, D15 17 D3, D4, D5, D6 Vr = 30V,Io= 1A,Vf= 0.47V ON Semiconductor MBR130T1G 4 18 D100, D101 Vr = 30V,Io= 0.2A,Vf= 0.65V DiodesInc. BAT54-7-F 2 20 J1,J2,J3,J4 PC Quick-Fit0.250Tab Keystone 4908 4 21 J5 CONN RCPT 10POS .8MM DL GOLD SAMTEC CLE-105-01-G-DV 1 SMD

22 J11,J12,J13,J14 200 millpad with165 millhole NONE NONE 4

23 L4 ShieldedDrum Core,0.56A,0.907Ohm Coiltronics DR74-221-R 1 24 P1 Header,TH, 100mil,1x2,Tinplated,230 Samtec Inc. TSW-102-07-T-S 1 milabove insulator 25 Q1, Q2, Q3, Q4 40A,53nC, rDS(on)@ 4.5V= 0.018Ohm InternationalRectifier IRF3205ZPBF 4 26 Q7, Q8, Q9 0.26A,0.81nC,rDS(on)@ 4.5V= 3 ON Semiconductor 2N7002ET1G 3 27 Q11 Transistor,NPN, 40V,0.15A,SOT-23 DiodesInc. MMBT4401-7-F 1 28 Q200 MOSFET, P-CH, -50V,-130A,SOT-323 DiodesInc. BSS84W-7-F 1 29 R1, R10 1%, 2W Stackpole CSNL 2 0.0041% R 2 30 R2, R54 1%, 0.125W Vishay-Dale CRCW0805178kFKEA 2 17SNOSB76C –December 2010–RevisedMay 2013 AN-2121 SolarMagic™ SM3320-BATT-EV Charge ControllerReferenceDesign SubmitDocumentationFeedback Copyright© 2010–2013,Texas InstrumentsIncorporated

BillofMaterials www.ti.com Designator Description Manufacturer PartNumber Qty 31 R3, R4, R22, R23, 1%, 0.1W Vishay-Dale CRCW060310k0FKEA 21 R30, R36, R42, R43, R45, R72, R100, R101, R102, R105, R106, R111, R119, R120, R121, R300, R400 32 R5 1%, 0.1W Vishay-Dale CRCW0603124kFKEA 1 33 R6 1%, 0.125W Vishay-Dale CRCW08051R00FNEA 1 34 R7, R13 1%, 0.25W Vishay-Dale CRCW120619k6FKEA 2 35 R8, R12, R24, R34 1%, 0.1W Vishay-Dale CRCW0603499RFKEA 4 36 R9 1%, 0.1W Vishay-Dale CRCW060312k4FKEA 1

37 R11, R14 1%, 1W Vishay-Dale CRCW121810R0FKEK 2

38 R15 1%, 0.1W Vishay-Dale CRCW06034k22FKEA 1 39 R17 1%, 0.1W Panasonic ERJ-3RQFR33V 1 40 R18, R19 RES, 10 ohm, 5%, 0.125W,0805 Vishay-Dale CRCW080510R0JNEA 2 41 R20, R29, R31, R47, 1%, 0.1W,RES, 2.00kohm, 1%, 0.1W, Vishay-Dale CRCW06032k00FKEA 5 R48 0603 42 R21 1%, 0.1W Vishay-Dale CRCW060349R9FKEA 1 43 R25, R35, R37, R44 5%, 0.1W Vishay-Dale CRCW06030000Z0EA 4 44 R26, R56, R87, R116 1%, 0.1W Vishay-Dale CRCW060360k4FKEA 4 45 R71, R73 1%, 0.1W,RES, 19.1kohm, 1%, 0.1W, Vishay-Dale CRCW060319k1FKEA 3 0603 46 R32, R33 RES, 4.99ohm, 1%, 0.125W,0805 Vishay-Dale CRCW08054R99FNEA 2 47 R38 1%, 0.1W Vishay-Dale CRCW060331k6FKEA 1 48 R39 RES, 1.00Meg ohm, 1%, 0.1W,0603 Vishay-Dale CRCW06031M00FKEA 1 49 R40 1%, 0.1W Vishay-Dale CRCW0603150kFKEA 1 50 R41 RES, 45.3kohm, 1%, 0.1W,0603 Vishay-Dale CRCW060345K3FKEA 1 51 R51, R52 RES, 12.4kohm, 1%, 0.25W,1206 Vishay-Dale CRCW120612K4FKEA 2 52 R53, R103 RES, 4.02kohm, 1%, 0.1W,0603 Vishay-Dale CRCW06034K02FKEA 2 54 R104 RES, 24.9kohm, 1%, 0.1W,0603 Vishay-Dale CRCW060324K9FKEA 1 55 R107, R108 RES, 270k ohm, 1%, 0.1W,0603 Yageo America RC0603FR-07270KL 2 56 R109 RES, 340k ohm, 1%, 0.1W,0603 Yageo America RC0603FR-07340KL 1 57 R110, R122 RES, 100k ohm, 1%, 0.1W,0603 Yageo America RC0603FR-07100KL 2 58 R112 RES, 511k ohm, 1%, 0.1W,0603 Vishay-Dale CRCW0603511KFKEA 1 59 R113, R117 RES, 22k ohm, 5%, 0.1W,0603 Vishay-Dale CRCW060322K0JNEA 2 61 R118 RES, 105k ohm, 1%, 0.1W,0603 Vishay-Dale CRCW0603105KFKEA 1 62 R200 RES, 604 ohm, 1%, 0.1W,0603 Vishay-Dale CRCW0603604RFKEA 1 63 R500, R600 RES, 100k ohm, 1%, 0.1W,0603 Vishay-Dale CRCW0603100KFKEA 2

64 TP1, TP2 TestPoint,SMT, Miniature KeystoneElectronics 5015 2

65 U1 150 mA, 100V Step-Down Switching Texas Instruments SM72485 1

66 U2, U3 1.6V,LLP-6 FactoryPresetTemperature Texas Instruments SM72480 2 Switchand TemperatureSensor

67 U5 SeriesofAdjustableMicropowerVoltage Texas Instruments SM72238 1

68 U7 Driver Texas Instruments SM72295 1

69 U8 DigitalController Texas Instruments SM72442 1

70 U9 5-PinMicroprocessorResetCircuits Texas Instruments SM72240 1

71 U11, U12 DualMicro-PowerRail-to-RailInputCMOS Texas Instruments SM72375 2

ComparatorwithOpen DrainOutput

72 L1 Inductor2 uH EFD-30 core PULSE PA2965-203NL 1

18 AN-2121 SolarMagic™ SM3320-BATT-EV Charge ControllerReferenceDesign SNOSB76C –December 2010–RevisedMay 2013 SubmitDocumentationFeedback Copyright© 2010–2013,Texas InstrumentsIncorporated

www.ti.com Charge ControllerSystem Schematic

17 Charge ControllerSystem Schematic

Figure20.Charge ControllerSystem Schematic,Part1 19SNOSB76C –December 2010–RevisedMay 2013 AN-2121 SolarMagic™ SM3320-BATT-EV Charge ControllerReference DesignSubmitDocumentationFeedback Copyright© 2010–2013,Texas InstrumentsIncorporated

Charge ControllerSystem Schematic www.ti.com Figure21.Charge ControllerSystem Schematic,Part2 20 AN-2121 SolarMagic™ SM3320-BATT-EV Charge ControllerReferenceDesign SNOSB76C –December 2010–RevisedMay 2013 SubmitDocumentationFeedback Copyright© 2010–2013,Texas InstrumentsIncorporated

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