Basic RF Testing of CCxxxx Devices - TI.com

1 ApplicationReportSWRA370 'low-powerRFproductswithanoverviewofthed ifferentcharacterizationtests(conducted, notradiated) ,thetermCCxxxxreferstothelow-powerCC25xx ,CC11xx,CC10XX, : RFTesting RXTest ConformanceTesting OutputPower SmartRFStudio TXTest CharacterizationTest SensitivitySmartRFis a , a a , a a August2011 BasicRFTestingofCCxxxxDevicesSubmitDocum entationFeedbackCopyright 2011, August2011 SubmitDocumentationFeedbackCopyright 2011, (Example).. (withoutLabVIEW) August2011 BasicRFTestingofCCxxxxDevicesSubmitDocum entationFeedbackCopyright 2011, 'low-powerRFproductswithanoverviewofthed ifferentcharacterizationtests(conducted, notradiated) betterunderstandingofthesystemsandfuncti ons, low-powerRFproductsmakeit easiertobuildwirelesslinksforremotecontr ol,metering, ,theyareusedinsideunlicensed,orlicense-f ree, ; ,ETSI, ( ).

2 Listsmanyofthetermsandabbreviationsusedi n decibels(dB)ofthemeasuredpowerdBmreferen cedto1 mWDUTD eviceundertestEBEvaluationboardEMEvaluat ionmoduleETSIE uropeanTelecommunicationsStandardsInstit uteEVME rrorvectormagnitudeFCCF ederalCommunicationsCommissionFSQF ullspectrumquantizationGUIG raphicaluserinterfaceIEEEI nstituteofElectricalandElectronicsEngine erINTI nterferencesource,interferencesignalISMI ndustrial,scientific,medicalMSKM inimumshiftkeyingPERP acketerrorratePSDP owerspectraldensityRSSIR eceivedsignalstrengthindicatorRXReceive, receiverSMASubMiniatureversionA connectorSoCSystemonchipSPIS erialparallelinterfaceTXTransmit,transmi ssion,transmitter4 BasicRFTestingofCCxxxxDevicesSWRA370 August2011 SubmitDocumentationFeedbackCopyright 2011, Bluetooth LowEnergyRFPHYS tandard ZigBee RF4 CEStandard ZigbeeStandard FCC,Section47 CFR15 Part15 Standard ETSIEN300440 Standard ETSIEN300220 Standard Rohde&Schwarz Agilent Anritsu Tektronix TestEquity typicaltestsystemgenerallyconsistsofthes ecomponentsandsubsystems: Signalanalyzers(spectrumanalyzers):These toolsarewidelyusedtomeasurethefrequencyr esponse,noise, typicaltestsystemusuallyrequiresonlyones ignalanalyzer.

3 Signalgenerators:Thesedevicesgeneraterep eatingornon-repeatingelectronicsignals(i neithertheanalogordigitaldomain).A typicalsystemshouldhaveatleasttwosignalg enerators:onetogeneratetheprimarysignal, signalsourcein ,thepowerresolutionmaynotbeasgoodasthatp roducedbya signalgenerator. singletemperaturechambershouldbesufficie ntformosttestsystems. Connectors/cables/splitters:Thesecompone ntsconnectdifferentsignalsusingcoaxialca blefromthetestsystemto(andfrom)thedevice undertest(DUT). LabVIEW :LabVIEW,orLaboratoryVirtualInstrumentat ionEngineeringWorkbench,is a softwareplatformanddevelopmentenvironmen tfora namedG. OriginallyreleasedfortheApple Macintosh in 1986,LabVIEWis commonlyusedfordataacquisition,instrumen tcontrol,andindustrialautomationona varietyofplatformsincludingMicrosoft Windows , variousversionsofUnix,Linux , usedasa platformtoautomatetheentiretestsystem.

4 SmartRF Studio:SmartRFStudio( ) is a is especiallyusefulforgenerationofconfigura tionregistervalues,forpracticaltestingof theRF5 SWRA370 August2011 BasicRFTestingofCCxxxxDevicesSubmitDocum entationFeedbackCopyright 2011, , RFIC developmentkits. Networkanalyzer(vectornetworkanalyzer):T histoolis ,butthereareothernetworkparametersetssuc hasy-parameters,z-parameters, ; is usefultohaveonenetworkanalyzeravailable. Oscilloscope:Thiselectronictestinstrumen tallowsuserstoobserveconstantlyvaryingsi gnalvoltages,usuallyasa two-dimensionalgraphofoneormoreelectrica lpotentialdifferenceswithaverticalorYaxi s,plottedasa functionoftime(horizontalorxaxis).Althou ghanoscilloscopedisplaysvoltageonthevert icalaxis,anyotherquantitythatcanbeconver tedtoa , usefulfora thetestconfiguration,thegreaterneedthere is ,then,oneshouldusea mindthatthecapabilitiesoftheavailableequ ipmentusedin a (WithoutLabVIEW) (one) (two) (combiner) (two) (UsingLabVIEW) (one) (combiner) (two)6 BasicRFTestingofCCxxxxDevicesSWRA370 August2011 SubmitDocumentationFeedbackCopyright 2011,TexasInstrumentsIncorporatedSmartRF Evaluation BoardUSB MCUPCW indows OSCEBALUSB DriverSmartRF Studio/LabVIEWS martRF Eval BoardFirmwareCCxxxx Transceiver/ CCxxxx SoCSPI/Debug (DUT)

5 Is connectedtothetesterviaa 50- thereis noantennainterface,a temporary50- interfaceora suitablecouplingdevice(50- load) ,theinputreferencesignal(bothasthedesire dsignalandtheinterferencesignal) used,theinterferencesignalcharacteristic smustbedefinedbytheapplicablestandardsfo rwhichthedeviceis (ChipconEvaluationBoardAccessLayer(CEBAL ). illustratestheconnectionbetweena , thefirmwareis out-of-date,SmartRFStudio7 August2011 BasicRFTestingofCCxxxxDevicesSubmitDocum entationFeedbackCopyright 2011,TexasInstrumentsIncorporatedAny board withTI LPRFR adioUSB MCUPCW indows OSCEBALUSB DriverSmartRF Studio/LabVIEWCEBAL FirmwareUSBC ableSmartRF Evaluation Board orCC DebuggerNote (1) is possibletoconnectyourownhardwaretotheSma rtRFEvaluationBoardtotestyourownradiodes ignwithSmartRFStudio7 ,orusethetargetconnectorontheCCDebugger. )

6 ForSoCs,usethedebuginterface;fortranscei vers,usetheserialperipheralinterface(SPI ).Figure2 showstheconnectionbetweena PCandagenericevaluationboardwitha TILPRF radio.(1)ConnecttheboardtotheTIevaluatio nboardviathebreak-outpinsontheboard, ,usethedebuginterface;fortransceivers, , youarenotusinglevelshiftersandthevoltage levelonyourboardis differentfromthevoltagelevelontheEB( ).Formoreinformation, ,it haslevelconvertersthatwilldetectthevolta geonthetargetboardandensurethatthedebugc ontrollinesaresettoa TXmodewhenusingLabVIEW: SettheDUTtoTXmodeusingSmartRFStudio7. SupplyandtemperaturearesetbyLabVIEW. Thesignalanalyzeris configuredbyLabVIEW tomeasurethetransmitteddata.

7 LabVIEW capturesthedatafromthesignalanalyzer. Thecollectedinformationthencanbeinterpre tedeitherin August2011 SubmitDocumentationFeedbackCopyright 2011,TexasInstrumentsIncorporatedf=CARRI ER FREQ[23:0]f2 XOSC16(( RXmodewhenusingLabVIEW: SettheDUTtoRXmodeusingSmartRFStudio7. Supply/temperaturearesetbyLabVIEW. Thesignalanalyzeris configuredbyLabVIEW totransmitdatacontinuouslyorin packetsthatadheretostandards. SmartRFStudio7/LabVIEW capturesthedatafromtheDUT. Thiscollectedinformationthencanbeinterpr etedeitherin vibratingpiezoelectriccrystaltocreateane lectricalsignalwitha commonlyusedtoprovidea temperature,humidity,pressure,andexterna lvibrationcanchangetheresonantfrequencyo fa alwayssomeinaccuracyin thecrystalsusedwithradios,onewaytocorrec tforthiserroris requiredin thechipis ,fortheCC2500thecarrierfrequencyis calculatedasshownbyEquation1:(1)WhereFRE Q[23.))]

8 0]is thebasefrequencyforthefrequencysynthesiz erin incrementsofHowever,theactualcrystalfreq uencyis notthesameasthestatedcrystalfrequencyasa , ,continuousTXmodewiththesettingsfoundusi ngSmartRFStudio,usea thenputintoEquation1 fromtheproductdatasheet, ,theFREQTUNE registeris '1111' extracapacitancetotheoscillator, result,thefinalcrystalfrequencycanbecont rolledbyadjustingthevalueoftheFREQTUNE registerin August2011 BasicRFTestingofCCxxxxDevicesSubmitDocum entationFeedbackCopyright 2011,TexasInstrumentsIncorporatedf=XOSCf =XOSCf= MHzXOSCFREQ[23:0]f2 CARRIER16 (((( GHz 26-MHzcrystalfora : FREQ2[23:16]= 0x5C FREQ1[15:8]= 0x4E FREQ0[7:0]= 0xC4 FREQ[23:0]= 0x5C4EC4 FREQ= 6049476[hextodecconversion]If themeasuredcarrierfrequencyis , :Eventhoughthecrystalis ratedat26 MHz,asa , August2011 SubmitDocumentationFeedbackCopyright 2011, (andsubsequentpages)canbeprintedanduseda sa liststhegeneraltestinstrumentdata.))))

9 ( ) August2011 BasicRFTestingofCCxxxxDevicesSubmitDocum entationFeedbackCopyright 2011,TexasInstrumentsIncorporatedPC with SmartRF Studio installedSmartRF Eval Boardand Eval ModuleSpectrum fora :Figure3 ,continuousTXmodewiththeappropriateoutpu tpowerlevelthroughSmartRFStudio( ). (dBm)(dBm)Pass/Fail?Freq1 (MHz)Freq2 (MHz)Freq3 (MHz)xxxxTestResults:12 BasicRFTestingofCCxxxxDevicesSWRA370 August2011 SubmitDocumentationFeedbackCopyright 2011,TexasInstrumentsIncorporated100 kHz-20 dB or more-30 dBm or with SmartRF Studio installedSmartRF Eval Boardand Eval ModuleSpectrum :ToverifythatthePSDoftheDUTis (Example)FrequencyRelativeLimitAbsoluteL imit|f fC|> 20dB :Figure5 (%)(%)Pass/Fail?

10 Freq1 (MHz)Freq2 (MHz)Freq3 (MHz)xxxxTestResults:13 SWRA370 August2011 BasicRFTestingofCCxxxxDevicesSubmitDocum entationFeedbackCopyright 2011,TexasInstrumentsIncorporatedQIError VectorMagnitude Error(IQ Error Magnitude)MeasuredSignalIdeal (Reference)SignalPhase Error(IQ Error Phase)fQIErrorVectorRange ofWorst-CaseErrorIdealConstellationPoint MeasuredPointPC with SmartRF Studio installedSmartRF Eval Boardand Eval ModuleSpectrum :Transmissionmodulationaccuracyis measuredusingerrorvectormagnitude(EVM).E VM,asillustratedin Figure6 andFigure7, is themagnitudeofthephasedifferenceasa :Figure8 thetoolusermanual.(SeeAppendixA formoreinformation.)Example:EVMmeasureme ntsonZigBeesignalsusinga Rohde&SchwarzFSQcanbesetupfollowingthein structionsin (%)at____kbp/s(%)Pass/Fail?