TPA3008D2 www.ti.com SLOS435C–MAY2004–REVISEDAUGUST2010 10-W STEREO CLASS-D AUDIO POWER AMPLIFIER CheckforSamples:TPA3008D2 FEATURES 1 DESCRIPTION • 10-W/ChannelIntoan16-Ω LoadFroma 2 17-VSupply The TPA3008D2 is a 10-W (per channel) efficient, • Upto92%Efficient,Class-DOperation class-D audio amplifier for driving bridged-tied stereo EliminatesNeedForHeatsinks speakers. The TPA3008D2 can drive stereo speakers as low as 8 Ω. The high efficiency of the TPA3008D2 • 8.5-Vto18-VSingle-SupplyOperation eliminates the need for external heatsinks when • FourSelectable,FixedGainSettings playingmusic. • DifferentialInputsMinimizesCommon-Mode The gain of the amplifier is controlled by two gain Noise select pins. The gain selections are 15.3, 21.2, 27.2, • Space-Saving,ThermallyEnhanced and31.8dB. PowerPAD™Packaging The outputs are fully protected against shorts to • ThermalandShort-CircuitProtection GND, VCC, and output-to-output shorts. A fault WithAutoRecoveryOption terminal allows short-circuit fault reporting and • PinoutSimilartoTPA3000DFamily automatic recovery. Thermal protection ensures that themaximumjunctiontemperatureisnotexceeded. APPLICATIONS • LCDMonitorsandTVs • All-In-OnePCs PVCC10 mF 10 mF PVCC 220 nF 220 nF 0.1 mF 0.1 mF SChounttdroolwn/Mute SHUTDOBSRNWNPVCCR PVCCR ROUTN ROUTN PGNDR PGNDR ROUTP ROUTP PVCCR PVCCR VBSRPCLAMPR 1 mF RInipguhtts Differential 0.47 mF RRIINNPN NNCC AVCC 0.47 mF V2P5 AVCC 0.47 mF Left Differential LINP NC Inputs 0.47 mF LINN NC 0.1 mF 10 mF 0.47 mF TPA3008D2 AVDDREF AGND NC AVDD Gain GAIN0 COSC 1 mF Control GAIN1 ROSC 220 pF FAULT AGND 120 kW NC VCLAMPL SLN VCCL VCCL OUTN OUTN GNDL GNDL OUTP OUTP VCCL VCCL SLP 1 mF B P P L L P P L L P P B 0.1 mF 0.1 mF 10 mF 10 mF 220 nF 220 nF PVCC PVCC † †Optional output filter for EMI suppression 1 Pleasebeawarethatanimportantnoticeconcerningavailability,standardwarranty,anduseincriticalapplicationsofTexas Instrumentssemiconductorproductsanddisclaimerstheretoappearsattheendofthisdatasheet. PowerPADisatrademarkofTexasInstruments. 2 PRODUCTIONDATAinformationiscurrentasofpublicationdate. Copyright©2004–2010,TexasInstrumentsIncorporated Products conform to specifications per the terms of the Texas Instruments standard warranty. Production processing does not necessarilyincludetestingofallparameters.

TPA3008D2 SLOS435C–MAY2004–REVISEDAUGUST2010 www.ti.com Thesedeviceshavelimitedbuilt-inESDprotection.Theleadsshouldbeshortedtogetherorthedeviceplacedinconductivefoam duringstorageorhandlingtopreventelectrostaticdamagetotheMOSgates. AVAILABLE OPTIONS PACKAGEDDEVICE TA 48-PINHTQFP(PHP)(1)(2) -40°Cto85°C TPA3008D2PHP (1) ThePHPpackageisavailabletapedandreeled.Toorderatapedandreeledpart,addthesuffixRtothepartnumber(e.g., TPA3008D2PHPR). (2) Forthemostcurrentpackageandorderinginformation,seethePackageOptionAddendumattheendofthisdocument,orseetheTI websiteatwww.ti.com. ABSOLUTE MAXIMUM RATINGS overoperatingfree-airtemperaturerange(unlessotherwisenoted) (1) TPA3008D2 Supplyvoltagerange AVCC,PVCC -0.3Vto20V LoadImpedance,RL ≥6Ω SHUTDOWN -0.3VtoVCC+0.3V Inputvoltagerange,VI GAIN0,GAIN1,RINN,RINP,LINN,LINP -0.3Vto6V Continuoustotalpowerdissipation SeeThermalInformationTable Operatingfree–airtemperaturerange,TA -40°Cto85°C Operatingjunctiontemperaturerange,TJ -40°Cto150°C Storagetemperaturerange,Tstg -65°Cto150°C (1) Stressesbeyondthoselistedunder“absolutemaximumratings”maycausepermanentdamagetothedevice.Thesearestressratings only,andfunctionaloperationofthedeviceattheseoranyotherconditionsbeyondthoseindicatedunder“recommendedoperating conditions”isnotimplied.Exposuretoabsolute–maximum–ratedconditionsforextendedperiodsmayaffectdevicereliability. THERMAL INFORMATION TPA3008D2 THERMALMETRIC(1)(2) UNITS PHP(48PINS) q Junction-to-ambientthermalresistance 27.7 JA q Junction-to-case(top)thermalresistance 14.8 JCtop q Junction-to-boardthermalresistance 9.4 JB °C/W y Junction-to-topcharacterizationparameter 0.6 JT y Junction-to-boardcharacterizationparameter 5.6 JB q Junction-to-case(bottom)thermalresistance 0.3 JCbot (1) Formoreinformationabouttraditionalandnewthermalmetrics,seetheICPackageThermalMetricsapplicationreport,SPRA953. (2) ForthermalestimatesofthisdevicebasedonPCBcopperarea,seetheTIPCBThermalCalculator. RECOMMENDED OPERATING CONDITIONS T =25°C(unlessotherwisenoted) A MIN MAX UNIT Supplyvoltage,VCC PVCC,AVCC 8.5 18 V High-levelinputvoltage,VIH SHUTDOWN,GAIN0,GAIN1 2 V Low-levelinputvoltage,VIL SHUTDOWN,GAIN0,GAIN1 0.8 V SHUTDOWN,VI=VCC=18V 10 µA High-levelinputcurrent,IIH GAIN0,GAIN1,VI=5.5V,VCC=18V 1 µA SHUTDOWN,VI=0V,VCC=18V 1 µA Low-levelinputcurrent,IIL GAIN0,GAIN1,VI=5.5V,VCC=18V 1 µA High-leveloutputvoltage,VOH FAULT,IOH=100µA AVDD-0.8V V Low-leveloutputvoltage,VOL FAULT,IOL=-100µA AGND+0.8V V 2 SubmitDocumentationFeedback Copyright©2004–2010,TexasInstrumentsIncorporated ProductFolderLink(s):TPA3008D2

TPA3008D2 www.ti.com SLOS435C–MAY2004–REVISEDAUGUST2010 RECOMMENDED OPERATING CONDITIONS (continued) T =25°C(unlessotherwisenoted) A MIN MAX UNIT FrequencyissetbyselectionofROSCandCOSC Oscillatorfrequency,fOSC (seetheApplicationInformationSection). 200 300 kHz Operatingfree–airtemperature,TA -40 85 °C DC ELECTRICAL CHARACTERISTICS T =25°C,V =12V,R =8Ω(unlessotherwisenoted) A CC L PARAMETER TESTCONDITIONS MIN TYP MAX UNIT Class-Doutputoffsetvoltage INNandINPconnectedtogether, |V | 5 55 mV OO (measureddifferentially) Gain=31.8dB V2P5 2.5-VBiasvoltage Noload 2.5 V I =10mA,SHUTDOWN=2V, AV +5-Vinternalsupplyvoltage L 4.5 5 5.5 V DD V =8.5Vto18V CC PSRR Powersupplyrejectionratio V =11.5Vto12.5V -76 dB CC I Quiescentsupplycurrent SHUTDOWN=2V,noload 11 22 mA CC Quiescentsupplycurrentin I SHUTDOWN=0V 1.6 25 µA CC(SD) shutdownmode Highside 600 V =12V, CC r Drain-sourceon-stateresistance I =1A, Lowside 500 mΩ DS(on) O T =25°C J Total 1100 1300 GAIN0=0.8V 14.6 15.3 16.2 GAIN1=0.8V GAIN0=2V 20.5 21.2 21.8 G Gain dB GAIN0=0.8V 26.4 27.2 27.8 GAIN1=2V GAIN0=2V 31.1 31.8 32.5 t Turnontime C =1µF,SHUTDOWN=2V 16 ms on (V2P5) t Turnofftime C =1µF,SHUTDOWN=0.8V 60 µs off (V2P5) AC ELECTRICAL CHARACTERISTICS T =25°C,V =12V,R =8Ω,(unlessotherwisenoted) A CC L PARAMETER TESTCONDITIONS MIN TYP MAX UNIT 200mV ripplefrom20Hzto1kHz, k Supplyvoltagerejectionratio PP -70 dB SVR Gain=15.6dB,Inputsac-coupledtoGND THD+N=0.13%,f=1kHz,R =8Ω 5 L THD+N=10%,f=1kHz,R =8Ω 8.5 L PO Continuousoutputpower THD+N=0.16%,f=1kHz,RL=16Ω, 5 W V =17V CC THD+N=10%,f=1kHz,R =16Ω, L 10 V =17V CC Totalharmonicdistortionplus THD+N P =1W,f=1kHz,R =8Ω 0.1% noise O L 20Hzto22kHz,A-weightedfilter, V Outputintegratednoisefloor -80 dB n Gain=15.6dB Crosstalk P =1W,R =8Ω,Gain=15.6dB, -93 dB O L f=1kHz MaximumoutputatTHD+N<0.5%, SNR Signal-to-noiseratio 97 dB f=1kHz,Gain=15.6dB Thermaltrippoint 150 °C Thermalhystersis 20 °C Copyright©2004–2010,TexasInstrumentsIncorporated SubmitDocumentationFeedback 3 ProductFolderLink(s):TPA3008D2

TPA3008D2 SLOS435C–MAY2004–REVISEDAUGUST2010 www.ti.com FUNCTIONALBLOCKDIAGRAM V2P5 PVCC V2P5 VClamp VCLAMPR Gen BSRN PVCCR(2) Gate ROUTN(2) Drive Deglitch RINN and PGNDR Gain Adj. PWM BSRP RINP Mode PVCCR(2) V2P5 Logic Gate ROUTP(2) Drive To Gain Adj. PGNDR GAIN0 Gain 4 Blocks and GAIN1 Control Start-up Logic FAULT V2P5 SC Detect ROSC Ramp Generator Biases Start-up and Thermal COSC and Protection VDD References Logic VDDok AVDDREF AVDD AVCC AVDD 5-V LDO VCCok AVCC PVCC AGND(2) TTL Input SHUTDOWN Buffer VClamp VCLAMPL (VCC Compl) Gen BSLN PVCCL(2) Gate LOUTN(2) V2P5 Drive Deglitch LINN and PGNDL Gain PWM BSLP Adj. LINP Mode PVCCL(2) Logic Gate LOUTP(2) Drive PGNDL 4 SubmitDocumentationFeedback Copyright©2004–2010,TexasInstrumentsIncorporated ProductFolderLink(s):TPA3008D2

TPA3008D2 www.ti.com SLOS435C–MAY2004–REVISEDAUGUST2010 PHPPACKAGE (TOPVIEW) R R N N R R P P R R N C C T T D D T T C C P R C C U U N N U U C C R S V V O O G G O O V V S B P P R R P P R R P P B 48 47 46 45 44 43 42 41 40 39 38 37 SHUTDOWN 1 36 VCLAMPR RINN 2 35 NC RINP 3 34 NC V2P5 4 33 AVCC LINP 5 32 NC LINN 6 31 NC TPA3008D2 AVDDREF 7 30 AGND NC 8 29 AVDD GAIN0 9 28 COSC GAIN1 10 27 ROSC FAULT 11 26 AGND NC 12 25 VCLAMPL 13 14 15 16 17 18 19 20 21 22 23 24 N L L N N L L P P L L P L C C T T D D T T C C L S C C U U N N U U C C S B V V O O G G O O V V B P P L L P P L L P P Copyright©2004–2010,TexasInstrumentsIncorporated SubmitDocumentationFeedback 5 ProductFolderLink(s):TPA3008D2

TPA3008D2 SLOS435C–MAY2004–REVISEDAUGUST2010 www.ti.com TERMINALFUNCTIONS PINNAME PINNUMBER I/O DESCRIPTION AGND 26,30 - Analoggroundfordigital/analogcellsincore AV 33 - High-voltageanalogpowersupply,notconnectedinternallytoPVCCRorPVCCL CC 5-VRegulatedoutputforusebyinternalcellsandGAIN0,GAIN1pinsonly.Not AV 29 O DD specifiedfordrivingotherexternalcircuitry. AV REF 7 O 5-VReferenceoutput—connecttogainsettingresistorordirectlytoGAIN0,GAIN1. DD BSLN 13 - BootstrapI/Oforleftchannel,negativehigh-sideFET BSLP 24 - BootstrapI/Oforleftchannel,positivehigh-sideFET BSRN 48 - BootstrapI/Oforrightchannel,negativehigh-sideFET BSRP 37 - BootstrapI/Oforrightchannel,positivehigh-sideFET COSC 28 I/O I/Oforcharge/dischargingcurrentsontocapacitorforrampgenerator. Short-circuitdetectfaultoutput. FAULT=high,short-circuitdetected. FAULT 11 O FAULT=low,normaloperation. StatusisresetwhenpoweriscycledorSHUTDOWNiscycled. GAIN0 9 I Gainselectleastsignificantbit.TTLlogiclevelswithcompliancetoAV . DD GAIN1 10 I Gainselectmostsignificantbit.TTLlogiclevelswithcompliancetoAV . DD LINN 6 I Negativeaudioinputforleftchannel LINP 5 I Positiveaudioinputforleftchannel LOUTN 16,17 O Class-D1/2-H-bridgenegativeoutputforleftchannel LOUTP 20,21 O Class-D1/2-H-bridgepositiveoutputforleftchannel 8,12,31,32, NC - Nointernalconnection 34,35 PGNDL 18,19 - PowergroundforleftchannelH-bridge PGNDR 42,43 - PowergroundforrightchannelH-bridge PowersupplyforleftchannelH-bridge(internallyconnectedtopins22and23),not PVCCL 14,15 - connectedtoPVCCRorAV . CC PowersupplyforleftchannelH-bridge(internallyconnectedtopins14and15),not PVCCL 22,23 - connectedtoPVCCRorAV . CC PowersupplyforrightchannelH-bridge(internallyconnectedtopins46and47), PVCCR 38,39 - notconnectedtoPVCCLorAV . CC PowersupplyforrightchannelH-bridge(internallyconnectedtopins38and39), PVCCR 46,47 - notconnectedtoPVCCLorAV . CC RINP 3 I Positiveaudioinputforrightchannel RINN 2 I Negativeaudioinputforrightchannel ROSC 27 I/O I/Ocurrentsettingresistorforrampgenerator. ROUTN 44,45 O Class-D1/2-H-bridgenegativeoutputforrightchannel ROUTP 40,41 O Class-D1/2-H-bridgepositiveoutputforrightchannel ShutdownsignalforIC(low=shutdown,high=operational).TTLlogiclevelswith SHUTDOWN 1 I compliancetoV . CC VCLAMPL 25 - Internallygeneratedvoltagesupplyforleftchannelbootstrapcapacitors. VCLAMPR 36 - Internallygeneratedvoltagesupplyforrightchannelbootstrapcapacitors. V2P5 4 O 2.5-VReferenceforanalogcells. ConnecttoAGNDandPGND—shouldbethecenterpointforbothgrounds.Internal ThermalPad - - resistiveconnectiontoAGND. TYPICAL CHARACTERISTICS Table1.TABLEOFGRAPHS FIGURE THD+N Totalharmonicdistortion+noise vsFrequency 1,2,3,4 THD+N Totalharmonicdistortion+noise vsOutputpower 5,6 Closed-loopresponse 7 6 SubmitDocumentationFeedback Copyright©2004–2010,TexasInstrumentsIncorporated ProductFolderLink(s):TPA3008D2

TPA3008D2 www.ti.com SLOS435C–MAY2004–REVISEDAUGUST2010 TYPICAL CHARACTERISTICS (continued) Table1.TABLEOFGRAPHS(continued) Outputpower vsSupplyvoltage 8,9 Efficiency vsOutputpower 10 Efficiency vsTotaloutputpower 11 V Supplycurrent vsTotaloutputpower 12 CC Crosstalk vsFrequency 13 k Supplyripplerejectionratio vsFrequency 14 SVR CMRR Commom-moderejectionratio vsFrequency 15 TOTALHARMONICDISTORTION+NOISE TOTALHARMONICDISTORTION+NOISE vs vs FREQUENCY FREQUENCY 10 10 Noise − % VRGCLa Ci=n = 1= 61 2 2(cid:1)1 V,.6, dB Noise − % VRGCLa Ci=n = 1= 61 2 8(cid:2)1 V.(cid:1)6, dB Distortion + 1 Distortion + 1 N −Total Harmonic 0.1 PO = 2.5 W N −Total Harmonic 0.1 PO = 1 WPO = 0.5 W THD+ 0.00.0051 PO = 0.5 WPO = 1 W THD+ 0.01 PO = 2.5 W 20 100 1 k 10 k 20 k 20 100 1 k 10 k 20 k f − Frequency − Hz f − Frequency − Hz Figure1. Figure2. Copyright©2004–2010,TexasInstrumentsIncorporated SubmitDocumentationFeedback 7 ProductFolderLink(s):TPA3008D2

TPA3008D2 SLOS435C–MAY2004–REVISEDAUGUST2010 www.ti.com TOTALHARMONICDISTORTION+NOISE TOTALHARMONICDISTORTION+NOISE vs vs FREQUENCY FREQUENCY 10 10 oise − % VRGCLa Ci=n = 8= 1 (cid:1)221 V.6, dB oise − % VRGCLa Ci=n = 8= 1 (cid:1)28,1 V.6, dB N N + + n n ortio 1 PO = 0.5 W ortio 1 PO = 2.5 W Dist Dist nic nic o o m m Har 0.1 PO = 1 W Har 0.1 Total PO = 2.5 W Total PO = 1 W − − N N + + D D H H 0.01 T T PO = 5 W 0.01 0.005 20 100 1 k 10 k 20 k 20 100 1 k 10 k 20 k f − Frequency − Hz f − Frequency − Hz Figure3. Figure4. TOTALHARMONICDISTORTION+NOISE TOTALHARMONICDISTORTION+NOISE vs vs OUTPUTPOWER OUTPUTPOWER 20 10 − % 10 VRCL C= =8 1(cid:1)2, V, − % VRCL C= =1 61 8(cid:1) V,, e Gain = 21.6 dB e Gain = 21.6 dB s s oi oi N N + + n n 1 o o orti 1 orti st st Di Di c c 1 kHz ni ni o o m m 0.1 ar 1 kHz ar al H 0.1 20 Hz al H 20 kHz ot ot N −T 20 kHz N −T 20 Hz + + HD HD 0.01 T 0.01 T 20m 100 m 200 m 1 2 10 20 20m 100 m 200 m 1 2 10 20 PO− Output Power − W PO− Output Power − W Figure5. Figure6. 8 SubmitDocumentationFeedback Copyright©2004–2010,TexasInstrumentsIncorporated ProductFolderLink(s):TPA3008D2

TPA3008D2 www.ti.com SLOS435C–MAY2004–REVISEDAUGUST2010 OUTPUTPOWER vs CLOSED-LOOPRESPONSE SUPPLYVOLTAGE 40 12 36 150 11 RL = 16 (cid:1) 10 32 100 9 28 W dB 24 Phase Gain 50 (cid:1)− ower − 78 THD+N = 10% n − 20 0 ase ut P 6 Gai 16 Ph utp 5 −50 − O 4 THD+N = 1% 12 O P VCC = 12 V, 3 8 RL = 8 W, −100 2 Gain = 32 dB 4 33 kHz, RC LPF −150 1 0 0 10 100 1k 10k 80k 8 9 10 11 12 13 14 15 16 17 18 f − Frequency − Hz VCC − Supply Voltage − V Figure7. Figure8. OUTPUTPOWER EFFICIENCY vs vs SUPPLYVOLTAGE OUTPUTPOWER 12 100 RL = 8 (cid:1) VCC = 18 V, 11 90 RL = 16 (cid:1) 10 80 9 70 W THD+N = 10% − wer 8 % 60 utput Po 67 ciency − 4500 − O 5 THD+N = 1% Effi 30 O P 4 20 3 Power represented by dashed line 10 may require external heatsinking 2 0 8 9 10 11 12 13 14 0 1 2 3 4 5 6 7 8 9 10 VCC − Supply Voltage − V PO − Output Power (Per Channel) − W Figure9. Figure10. Copyright©2004–2010,TexasInstrumentsIncorporated SubmitDocumentationFeedback 9 ProductFolderLink(s):TPA3008D2

TPA3008D2 SLOS435C–MAY2004–REVISEDAUGUST2010 www.ti.com EFFICIENCY SUPPLYCURRENT vs vs TOTALOUTPUTPOWER TOTALOUTPUTPOWER 100 2.0 16 (cid:1) LC Filter, 90 1.8 Resistive Load, Stereo Operation 80 1.6 8 (cid:1) 70 nt − A 1.4 VCCR L= =1 28 V(cid:1), − % 60 urre 1.2 y C VCC = 12 V, enc 50 ply 1 RL = 16 (cid:1) Effici 40 − Sup 0.8 C 30 VC 0.6 VCC = 18 V, 20 VCC = 12 V, 0.4 RL = 16 (cid:1) LC Filter, Resistive Load, 10 0.2 Stereo Operation 0 0 0 1 2 3 4 5 6 7 8 9 10 11 12 0 2 4 6 8 10 12 14 16 18 20 PO − Total Output Power − W PO − Total Output Power − W Figure11. Figure12. CROSSTALK SUPPLYRIPPLEREJECTIONRATIO vs vs FREQUENCY FREQUENCY 0 0 VCC = 12 V, B −−2100 PGROLa i==n 82=(cid:1). 52 1W.6, dB atio − d −−2100 VVRC(LR C=IP =P8 L 1(cid:1)E2,) V=, 200 mVPP, R Gain = 15.6 dB n −30 o −30 B cti stalk − d −−5400 pple Reje −−5400 Cros −60 y Ri −60 pl −70 up −70 S − −80 R −80 V S −90 k −90 −100 −100 20 100 1 k 10 k 20 k 20 100 1 k 10 k 20 k f − Frequency − Hz f − Frequency − Hz Figure13. Figure14. 10 SubmitDocumentationFeedback Copyright©2004–2010,TexasInstrumentsIncorporated ProductFolderLink(s):TPA3008D2

TPA3008D2 www.ti.com SLOS435C–MAY2004–REVISEDAUGUST2010 COMMON-MODEREJECTIONRATIO vs FREQUENCY 0 B VCC = 12 V, d Gain = 15.6 dB, o − −10 RL = 8 (cid:2)(cid:1) ati Output Referred R n −20 o cti e ej −30 R e d o M −40 n- o m m −50 o C − R −60 R M C −70 20 100 1 k 10 k 20 k f − Frequency − Hz Figure15. Copyright©2004–2010,TexasInstrumentsIncorporated SubmitDocumentationFeedback 11 ProductFolderLink(s):TPA3008D2

TPA3008D2 SLOS435C–MAY2004–REVISEDAUGUST2010 www.ti.com APPLICATION INFORMATION (cid:1) (cid:1) PVCC 1 nF 1 nF PVCC 220 nF 220 nF 10 (cid:3)F 10 (cid:3)F 0.1 (cid:3)F 0.1 (cid:3)F RN CR CR TN TN DR DR TP TP CR CR RP S C C U U N N U U C C S Shutdown/Mute B PV PV RO RO PG PG RO RO PV PV B 1 (cid:3)F Control SHUTDOWN VCLAMPR Right Differential RINN NC Inputs 0.47 (cid:3)F RINP NC AVCC 0.47 (cid:3)F V2P5 AVCC 0.47 (cid:3)F Left Differential LINP NC Inputs 0.47 (cid:3)F LINN NC 0.1 (cid:3)F 10 (cid:3)F 0.47 (cid:3)F TPA3008D2 AVDDREF AGND NC AVDD 1 (cid:3)F GAIN0 COSC Gain 220 pF Control GAIN1 ROSC 120 k(cid:2) Fault Reporting FAULT AGND NC VCLAMPL L L N N L L P P L L N C C T T D D T T C C P 1 (cid:3)F L C C U U N N U U C C L S V V O O G G O O V V S B P P L L P P L L P P B 0.1 (cid:3)F 0.1 (cid:3)F 10 (cid:3)F 10 (cid:3)F 220 nF 220 nF PVCC 1 nF 1 nF PVCC (cid:1) (cid:1) (cid:1) Chip ferrite bead (example: Fair-Rite 251206700743) shown for EMI suppression. Figure16. StereoClass-DWithDifferentialInputs 12 SubmitDocumentationFeedback Copyright©2004–2010,TexasInstrumentsIncorporated ProductFolderLink(s):TPA3008D2

TPA3008D2 www.ti.com SLOS435C–MAY2004–REVISEDAUGUST2010 CLASS-D OPERATION Thissectionfocusesontheclass-DoperationoftheTPA3008D2. Traditional Class-D Modulation Scheme The traditional class-D modulation scheme, which is used in the TPA032D0x family, has a differential output where each output is 180 degrees out of phase and changes from ground to the supply voltage, V . Therefore, CC the differential prefiltered output varies between positive and negative V , where filtered 50% duty cycle yields CC 0 V across the load. The traditional class-D modulation scheme with voltage and current waveforms is shown in Figure 17. Note that even at an average of 0 V across the load (50% duty cycle), the current to the load is high, causinghighlossandthuscausingahighsupplycurrent. OUTP OUTN +12 V Differential Voltage 0 V Across Load −12 V Current Figure17. TraditionalClass-DModulationScheme'sOutputVoltageandCurrentWaveformsIntoan InductiveLoadWithNoInput TPA3008D2 Modulation Scheme The TPA3008D2 uses a modulation scheme that still has each output switching from 0 to the supply voltage. However, OUTP and OUTN are now in phase with each other with no input. The duty cycle of OUTP is greater than 50% and OUTN is less than 50% for positive output voltages. The duty cycle of OUTP is less than 50% and OUTN is greater than 50% for negative output voltages. The voltage across the load sits at 0 V throughout most oftheswitchingperiod,greatlyreducingtheswitchingcurrent,whichreducesanyI2Rlossesintheload. Copyright©2004–2010,TexasInstrumentsIncorporated SubmitDocumentationFeedback 13 ProductFolderLink(s):TPA3008D2

TPA3008D2 SLOS435C–MAY2004–REVISEDAUGUST2010 www.ti.com OUTP OUTN Output = 0 V Differential +12 V Voltage 0 V Across −12 V Load Current OUTP OUTN Output > 0 V Differential +12 V Voltage 0 V Across −12 V Load Current Figure18. TheTPA3008D2OutputVoltageandCurrentWaveformsIntoanInductiveLoad Efficiency: LC Filter Required With the Traditional Class-D Modulation Scheme The main reason that the traditional class-D amplifier needs an output filter is that the switching waveform results in maximum current flow. This causes more loss in the load, which causes lower efficiency. The ripple current is large for the traditional modulation scheme, because the ripple current is proportional to voltage multiplied by the time at that voltage. The differential voltage swing is 2 x V , and the time at each voltage is half the period for CC the traditional modulation scheme. An ideal LC filter is needed to store the ripple current from each half cycle for the next half cycle, while any resistance causes power dissipation. The speaker is both resistive and reactive, whereasanLCfilterisalmostpurelyreactive. The TPA3008D2 modulation scheme has little loss in the load without a filter because the pulses are short and the change in voltage is V instead of 2 x V . As the output power increases, the pulses widen, making the CC CC ripple current larger. Ripple current could be filtered with an LC filter for increased efficiency, but for most applicationsthefilterisnotneeded. An LC filter with a cutoff frequency less than the class-D switching frequency allows the switching current to flow through the filter instead of the load. The filter has less resistance than the speaker, which results in less power dissipation,thereforeincreasingefficiency. Effects of Applying a Square Wave Into a Speaker Audio specialists have advised for years not to apply a square wave to speakers. If the amplitude of the waveform is high enough and the frequency of the square wave is within the bandwidth of the speaker, the square wave could cause the voice coil to jump out of the air gap and/or scar the voice coil. A 250-kHz switching frequency, however, does not significantly move the voice coil, as the cone movement is proportional to 1/f2 for frequenciesbeyondtheaudioband. 14 SubmitDocumentationFeedback Copyright©2004–2010,TexasInstrumentsIncorporated ProductFolderLink(s):TPA3008D2

TPA3008D2 www.ti.com SLOS435C–MAY2004–REVISEDAUGUST2010 Damage may occur if the voice coil cannot handle the additional heat generated from the high-frequency switching current. The amount of power dissipated in the speaker may be estimated by first considering the overall efficiency of the system. If the on-resistance (rds(on)) of the output transistors is considered to cause the dominant loss in the system, then the maximum theoretical efficiency for the TPA3008D2 with an 8-Ω load is as follows: R L 8 Efficiency(theoretical, %) (cid:3) (cid:1)100%(cid:3) (cid:1)100%(cid:3)86% (cid:4) (cid:5) (8(cid:2)1.3) RL(cid:2)rds(on) (1) The maximum measured output power is approximately 8.5 W with an 12-V power supply. The total theoretical powersupplied(P(total))forthisworst-caseconditionwouldthereforebeasfollows: P P (cid:1) O (cid:1)8.5W(cid:1)9.88W (total) Efficiency 0.86 (2) The efficiency measured in the lab using an 8-Ω speaker was 81%. The power not accounted for as dissipated acrossther maybecalculatedbysimplysubtractingthetheoreticalpowerfromthemeasuredpower: DS(on) Otherlosses(cid:2)P (measured)(cid:1)P (theoretical) (cid:2) 10.49 (cid:1) 9.88 (cid:2) 0.61W (total) (total) (3) The quiescent supply current at 12 V is measured to be 22 mA. It can be assumed that the quiescent current encapsulates all remaining losses in the device, i.e., biasing and switching losses. It may be assumed that any remainingpowerisdissipatedinthespeakerandiscalculatedasfollows: P (cid:3)0.61W (cid:2) (12V(cid:1)22mA) (cid:3) 0.35W (dis) (4) Note that these calculations are for the worst-case condition of 8.5 W delivered to the speaker. Because the 0.35 W is only 4% of the power delivered to the speaker, it may be concluded that the amount of power actually dissipated in the speaker is relatively insignificant. Furthermore, this power dissipated is well within the specifications of most loudspeaker drivers in a system, as the power rating is typically selected to handle the powergeneratedfromaclippingwaveform. When to Use an Output Filter for EMI Suppression Design the TPA3008D2 without the filter if the traces from amplifier to speaker are short (< 50 cm). Powered speakers, where the speaker is in the same enclosure as the amplifier, is a typical application for class-D without afilter. Most applications require a ferrite bead filter. The ferrite filter reduces EMI around 1 MHz and higher (FCC and CE only test radiated emissions greater than 30 MHz). When selecting a ferrite bead, choose one with high impedanceathighfrequencies,butlowimpedanceatlowfrequencies. Use a LC output filter if there are low frequency (<1 MHz) EMI-sensitive circuits and/or there are long wires from theamplifiertothespeaker. When both an LC filter and a ferrite bead filter are used, the LC filter should be placed as close as possible to theICfollowedbytheferritebeadfilter. 33 m H OUTP L1 C1 0.1C m2F 0.47 m F 33 m H OUTN L2 C3 0.1 m F Figure19. TypicalLCOutputFilter,CutoffFrequencyof27kHz,SpeakerImpedance=8Ω Copyright©2004–2010,TexasInstrumentsIncorporated SubmitDocumentationFeedback 15 ProductFolderLink(s):TPA3008D2

TPA3008D2 SLOS435C–MAY2004–REVISEDAUGUST2010 www.ti.com Ferrite Chip Bead OUTP 1 nF Ferrite Chip Bead OUTN 1 nF Figure20. TypicalFerriteChipBeadFilter(Chipbeadexample:Fair-Rite2512067007Y3) Gain setting via GAIN0 and GAIN1 inputs ThegainoftheTPA3008D2issetbytwoinputterminals,GAIN0andGAIN1. The gains listed in Table 2 are realized by changing the taps on the input resistors inside the amplifier. This causes the input impedance (Z) to be dependent on the gain setting. The actual gain settings are controlled by i ratios of resistors, so the gain variation from part-to-part is small. However, the input impedance may shift by 20%duetoshiftsintheactualresistanceoftheinputresistors. For design purposes, the input network (discussed in the next section) should be designed assuming an input impedance of 26 kΩ, which is the absolute minimum input impedance of the TPA3008D2. At the lower gain settings,theinputimpedancecouldincreaseashighas165kΩ Table2.GainSetting INPUTIMPEDANCE AMPLIFIERGAIN(dB) GAIN1 GAIN0 (kΩ) TYP TYP 0 0 15.3 137 0 1 21.2 88 1 0 27.2 52 1 1 31.8 33 INPUT RESISTANCE Each gain setting is achieved by varying the input resistance of the amplifier that can range from its smallest value, 33 kΩ, to the largest value, 137 kΩ. As a result, if a single capacitor is used in the input high-pass filter, the-3dBorcutofffrequencychangeswhenchanginggainsteps. Zf Input Ci IN Zi Signal The-3-dBfrequencycanbecalculatedusingEquation5.UseTable2forZ values. i f(cid:1) 1 2(cid:1) ZC i i (5) 16 SubmitDocumentationFeedback Copyright©2004–2010,TexasInstrumentsIncorporated ProductFolderLink(s):TPA3008D2

TPA3008D2 www.ti.com SLOS435C–MAY2004–REVISEDAUGUST2010 INPUT CAPACITOR, C I In the typical application, an input capacitor (C) is required to allow the amplifier to bias the input signal to the i proper dc level for optimum operation. In this case, C and the input impedance of the amplifier (Z) form a i i high-passfilterwiththecornerfrequencydeterminedinEquation6. −3 dB f (cid:1) 1 c 2(cid:1)ZC i i fc (6) The value of C is important, as it directly affects the bass (low-frequency) performance of the circuit. Consider i the example where Z is 137 kΩ and the specification calls for a flat bass response down to 20 Hz. Equation 6 is i reconfiguredasEquation7. C (cid:1) 1 i 2(cid:1)Z f i c (7) In this example, C is 58 nF; so, one would likely choose a value of 0.1 µF as this value is commonly used. If the i gain is known and is constant, use Z from Table 2 to calculate C. A further consideration for this capacitor is the i i leakage path from the input source through the input network (C) and the feedback network to the load. This i leakage current creates a dc offset voltage at the input to the amplifier that reduces useful headroom, especially in high gain applications. For this reason, a low-leakage tantalum or ceramic capacitor is the best choice. When polarized capacitors are used, the positive side of the capacitor should face the amplifier input in most applications as the dc level there is held at 2.5 V, which is likely higher than the source dc level. Note that it is importanttoconfirmthecapacitorpolarityintheapplication. Forthebestpopperformance,C shouldbelessthanorequalto1µF. I PowerSupplyDecoupling,C S The TPA3008D2 is a high-performance CMOS audio amplifier that requires adequate power supply decoupling to ensure that the output total harmonic distortion (THD) is as low as possible. Power supply decoupling also prevents oscillations for long lead lengths between the amplifier and the speaker. The optimum decoupling is achieved by using two capacitors of different types that target different types of noise on the power supply leads. Forhigherfrequencytransients,spikes,ordigitalhashontheline,agoodlowequivalent-series-resistance(ESR) ceramic capacitor, typically 0.1 µF placed as close as possible to the device V lead works best. For filtering CC lower frequency noise signals, a larger aluminum electrolytic capacitor of 10 µF or greater placed near the audio power amplifier is recommended. The 10-µF capacitor also serves as local storage capacitor for supplying currentduringlargesignaltransientsontheamplifieroutputs. BSNandBSPCapacitors The full H-bridge output stages use only NMOS transistors. Therefore, they require bootstrap capacitors for the high side of each output to turn on correctly. A 220-nF ceramic capacitor, rated for at least 25 V, must be connected from each output to its corresponding bootstrap input. Specifically, one 220-nF capacitor must be connected from xOUTP to xBSP, and one 220-nF capacitor must be connected from xOUTN to xBSN. (See the applicationcircuitdiagraminFigure16.) The bootstrap capacitors connected between the BSxx pins and corresponding output function as a floating power supply for the high-side N-channel power MOSFET gate drive circuitry. During each high-side switching cycle, the bootstrap capacitors hold the gate-to-source voltage high enough to keep the high-side MOSFETs turnedon. Copyright©2004–2010,TexasInstrumentsIncorporated SubmitDocumentationFeedback 17 ProductFolderLink(s):TPA3008D2

TPA3008D2 SLOS435C–MAY2004–REVISEDAUGUST2010 www.ti.com VCLAMPCapacitors To ensure that the maximum gate-to-source voltage for the NMOS output transistors is not exceeded, two internal regulators clamp the gate voltage. Two 1-µF capacitors must be connected from VCLAMPL (pin 25) and VCLAMPR (pin 36) to ground and must be rated for at least 25 V. The voltages at the VCLAMP terminals vary withV andmaynotbeusedforpoweringanyothercircuitry. CC InternalRegulated5-VSupply(AV ) DD The AV terminal (pin 29) is the output of an internally generated 5-V supply, used for the oscillator, DD preamplifier, and volume control circuitry. It requires a 1-µF capacitor, placed close to the pin, to keep the regulatorstable. This regulated voltage can be used to control GAIN0 and GAIN1 terminals, but should not be used to drive externalcircuitry. DifferentialInput The differential input stage of the amplifier cancels any noise that appears on both input lines of the channel. To use the TPA3008D2 with a differential source, connect the positive lead of the audio source to the INP input and the negative lead from the audio source to the INN input. To use the TPA3008D2 with a single-ended source, ac ground the INP or INN input through a capacitor equal in value to the input capacitor on INN or INP and apply the audio source to either input. In a single-ended input application, the unused input should be ac grounded at theaudiosourceinsteadofatthedeviceinputforbestnoiseperformance. SHUTDOWN OPERATION The TPA3008D2 employs a shutdown mode of operation designed to reduce supply current (I ) to the absolute CC minimum level during periods of nonuse for power conservation. The SHUTDOWN input terminal should be held high (see specification table for trip point) during normal operation when the amplifier is in use. Pulling SHUTDOWN low causes the outputs to mute and the amplifier to enter a low-current state. Never leave SHUTDOWNunconnected,becauseamplifieroperationwouldbeunpredictable. For the best power-off pop performance, place the amplifier in the shutdown mode prior to removing the power supplyvoltage. USING LOW-ESR CAPACITORS Low-ESRcapacitorsarerecommendedthroughoutthisapplicationsection.Areal(asopposedtoideal)capacitor can be modeled simply as a resistor in series with an ideal capacitor. The voltage drop across this resistor minimizes the beneficial effects of the capacitor in the circuit. The lower the equivalent value of this resistance, themoretherealcapacitorbehaveslikeanidealcapacitor. 18 SubmitDocumentationFeedback Copyright©2004–2010,TexasInstrumentsIncorporated ProductFolderLink(s):TPA3008D2

TPA3008D2 www.ti.com SLOS435C–MAY2004–REVISEDAUGUST2010 SHORT-CIRCUIT PROTECTION AND AUTOMATIC RECOVERY FEATURE The TPA3008D2 has short-circuit protection circuitry on the outputs that prevents damage to the device during output-to-output shorts, output-to-GND shorts, and output-to-V shorts. When a short circuit is detected on the CC outputs, the part immediately disables the output drive. This is a latched fault and must be reset by cycling the voltage on the SHUTDOWN pin to a logic low and back to the logic high state for normal operation. This clears the short-circuit flag and allows for normal operation if the short was removed. If the short was not removed, the protectioncircuitryagainactivates. The fault terminal can be used for automatic recovery from a short-circuit event, or used to monitor the status withanexternalGPIO. THERMAL PROTECTION Thermal protection on the TPA3008D2 prevents damage to the device when the internal die temperature exceeds 150°C. There is a ±15 degree tolerance on this trip point from device to device. Once the die temperature exceeds the thermal set point, the device enters into the shutdown state and the outputs are disabled. This is not a latched fault. The thermal fault is cleared once the temperature of the die is reduced by 20°C.Thedevicebeginsnormaloperationatthispointwithnoexternalsysteminteraction. PRINTED-CIRCUIT BOARD (PCB) LAYOUT Because the TPA3008D2 is a class-D amplifier that switches at a high frequency, the layout of the printed-circuit board(PCB)shouldbeoptimizedaccordingtothefollowingguidelinesforthebestpossibleperformance. • Decoupling capacitors—The high-frequency 0.1-µF decoupling capacitors should be placed as close to the PVCC (pins 14, 15, 22, 23, 38, 39, 46, and 47) and AV (pin 33) terminals as possible. The V2P5 (pin 4) CC capacitor,AV (pin29)capacitor,andVCLAMP(pins25and36)capacitorshouldalsobeplacedascloseto DD the device as possible. Large (10 µF or greater) bulk power supply decoupling capacitors should be placed neartheTPA3008D2onthePVCCL,PVCCR,andAV terminals. CC • Grounding—The AV (pin 33) decoupling capacitor, AV (pin 29) capacitor, V2P5 (pin 4) capacitor, COSC CC DD (pin 28) capacitor, and ROSC (pin 27) resistor should each be grounded to analog ground (AGND, pins 26 and 30). The PVCC decoupling capacitors should each be grounded to power ground (PGND, pins 18, 19, 42,and43).AnaloggroundandpowergroundmaybeconnectedatthePowerPAD,whichshouldbeusedas a central ground connection or star ground for the TPA3008D2. Basically, an island should be created with a singleconnectiontoPGNDatthePowerPAD. • Output filter—The ferrite EMI filter (Figure 20) should be placed as close to the output terminals as possible for the best EMI performance. The LC filter (Figure 19) should be placed close to the outputs. The capacitors used in both the ferrite and LC filters should be grounded to power ground. If both filters are used, the LC filtershouldbeplacedfirst,followingtheoutputs. • PowerPAD—The PowerPAD must be soldered to the PCB for proper thermal performance and optimal reliability. The dimensions of the PowerPAD thermal land should be 5 mm by 5 mm (197 mils by 197 mils). The PowerPAD size measures 4,55 x 4,55 mm. Four rows of solid vias (four vias per row, 0,3302 mm or 13 mils diameter) should be equally spaced underneath the thermal land. The vias should connect to a solid copper plane, either on an internal layer or on the bottom layer of the PCB. The vias must be solid vias, not thermal relief or webbed vias. For additional information, see the PowerPAD Thermally Enhanced Package applicationnote,(SLMA002). For an example layout, see the TPA3008D2 Evaluation Module (TPA3008D2EVM) User Manual, (SLOU165). Both the EVM user manual and the PowerPAD application note are available on the TI Web site at http://www.ti.com. Copyright©2004–2010,TexasInstrumentsIncorporated SubmitDocumentationFeedback 19 ProductFolderLink(s):TPA3008D2

TPA3008D2 SLOS435C–MAY2004–REVISEDAUGUST2010 www.ti.com BASIC MEASUREMENT SYSTEM Thisapplicationnotefocusesonmethodsthatusethebasicequipmentlistedbelow: • Audioanalyzerorspectrumanalyzer • Digitalmultimeter(DMM) • Oscilloscope • Twisted-pairwires • Signalgenerator • Powerresistor(s) • Linearregulatedpowersupply • Filtercomponents • EVMorothercompleteaudiocircuit Figure 21 shows the block diagrams of basic measurement systems for class-AB and class-D amplifiers. A sine wave is normally used as the input signal because it consists of the fundamental frequency only (no other harmonics are present). An analyzer is then connected to the APA output to measure the voltage output. The analyzer must be capable of measuring the entire audio bandwidth. A regulated dc power supply is used to reduce the noise and distortion injected into the APA through the power pins. A System Two audio measurement system(AP-II)(Reference1)byAudioPrecisionincludesthesignalgeneratorandanalyzerinonepackage. The generator output and amplifier input must be ac-coupled. However, the EVMs already have the ac-coupling capacitors, (C ), so no additional coupling is required. The generator output impedance should be low to avoid IN attenuating the test signal, and is important because the input resistance of APAs is not high. Conversely, the analyzer-input impedance should be high. The output impedance, R , of the APA is normally in the hundreds OUT ofmilliohmsandcanbeignoredforallbutthepower-relatedcalculations. Figure 21(a) shows a class-AB amplifier system. It takes an analog signal input and produces an analog signal output.ThisamplifiercircuitcanbedirectlyconnectedtotheAP-IIorotheranalyzerinput. This is not true of the class-D amplifier system shown in Figure 21(b), which requires low-pass filters in most cases in order to measure the audio output waveforms. This is because it takes an analog input signal and converts it into a pulse-width modulated (PWM) output signal that is not accurately processed by some analyzers. 20 SubmitDocumentationFeedback Copyright©2004–2010,TexasInstrumentsIncorporated ProductFolderLink(s):TPA3008D2

TPA3008D2 www.ti.com SLOS435C–MAY2004–REVISEDAUGUST2010 Power Supply Signal APA R Analyzer Generator L 20 Hz − 20 kHz (a) Basic Class−AB Power Supply Low-Pass RC Filter Signal Class-D APA R(A) Analyzer Generator L 20 Hz − 20 kHz Low-Pass RC Filter (b) Filter-Free and Traditional Class-D (A) For efficiency measurements with filter-free class-D, RL should be an inductive load like a speaker. Figure21. AudioMeasurementSystems The TPA3008D2 uses a modulation scheme that does not require an output filter for operation, but they do sometimes require an RC low-pass filter when making measurements. This is because some analyzer inputs cannot accurately process the rapidly changing square-wave output and therefore record an extremely high level of distortion. The RC low-pass measurement filter is used to remove the modulated waveforms so the analyzer canmeasuretheoutputsinewave. DIFFERENTIAL INPUT AND BTL OUTPUT All of the class-D APAs and many class-AB APAs have differential inputs and bridge-tied load (BTL) outputs. Differential inputs have two input pins per channel and amplify the difference in voltage between the pins. Differential inputs reduce the common-mode noise and distortion of the input circuit. BTL is a term commonly used in audio to describe differential outputs. BTL outputs have two output pins providing voltages that are 180 degrees out of phase. The load is connected between these pins. This has the added benefits of quadrupling the outputpowertotheloadandeliminatingadcblockingcapacitor. A block diagram of the measurement circuit is shown in Figure 22. The differential input is a balanced input, meaning the positive (+) and negative (-) pins have the same impedance to ground. Similarly, the BTL output equatestoabalancedoutput. Copyright©2004–2010,TexasInstrumentsIncorporated SubmitDocumentationFeedback 21 ProductFolderLink(s):TPA3008D2

TPA3008D2 SLOS435C–MAY2004–REVISEDAUGUST2010 www.ti.com Evaluation Module Audio Power Generator Amplifier Analyzer C Low−Pass IN RC Filter VGEN RGEN CIN RIN ROUT RL RANA CANA Low−Pass RGEN RIN ROUT RC Filter RANA CANA Twisted-Pair Wire Twisted-Pair Wire Figure22. DifferentialInput,BTLOutputMeasurementCircuit The generator should have balanced outputs, and the signal should be balanced for best results. An unbalanced output can be used, but it may create a ground loop that affects the measurement accuracy. The analyzer must alsohavebalancedinputsforthesystemtobefullybalanced, thereby cancelling out any common-mode noise in thecircuitandprovidingthemostaccuratemeasurement. ThefollowinggeneralrulesshouldbefollowedwhenconnectingtoAPAswithdifferentialinputsandBTLoutputs: • Useabalancedsourcetosupplytheinputsignal. • Useananalyzerwithbalancedinputs. • Usetwisted-pairwireforallconnections. • Useshieldingwhenthesystemenvironmentisnoisy. • Ensure that the cables from the power supply to the APA, and from the APA to the load, can handle the large currents(seeTable3). Table 3 shows the recommended wire size for the power supply and load cables of the APA system. The real concern is the dc or ac power loss that occurs as the current flows through the cable. These recommendations arebasedon12-inchlongwirewitha20-kHzsine-wavesignalat25°C. Table3.RecommendedMinimumWireSizeforPowerCables DCPOWERLOSS ACPOWERLOSS P (W) R (Ω) AWGSize OUT L (MW) (MW) 10 4 18 22 16 40 18 42 2 4 18 22 3.2 8 3.7 8.5 1 8 22 28 2 8 2.1 8.1 <0.75 8 22 28 1.5 6.1 1.6 6.2 CLASS-D RC LOW-PASS FILTER An RC filter is used to reduce the square-wave output when the analyzer inputs cannot process the pulse-width modulated class-D output waveform. This filter has little effect on the measurement accuracy because the cutoff frequency is set above the audio band. The high frequency of the square wave has negligible impact on measurement accuracy because it is well above the audible frequency range, and the speaker cone cannot respond at such a fast rate. The RC filter is not required when an LC low-pass filter is used, such as with the class-DAPAsthatemploythetraditionalmodulationscheme(TPA032D0x,TPA005Dxx). The component values of the RC filter are selected using the equivalent output circuit as shown in Figure 23. R L is the load impedance that the APA is driving for the test. The analyzer input impedance specifications should be available and substituted for R and C . The filter components, R and C , can then be derived for the ANA ANA FILT FILT system. The filter should be grounded to the APA near the output ground pins or at the power supply ground pin tominimizegroundloops. 22 SubmitDocumentationFeedback Copyright©2004–2010,TexasInstrumentsIncorporated ProductFolderLink(s):TPA3008D2

TPA3008D2 www.ti.com SLOS435C–MAY2004–REVISEDAUGUST2010 Load RC Low-Pass Filters AP Analyzer Input R FILT C C R FILT ANA ANA V= V R L IN V L OUT R FILT C C R FILT ANA ANA To APA GND Figure23. MeasurementLow-PassFilterDerivationCircuit-Class-DAPAs The transfer function for this circuit is shown in Equation 8 where w = R C , R = R || R and O EQ EQ EQ FILT ANA C = (C + C ). The filter frequency should be set above f , the highest frequency of the measurement EQ FILT ANA MAX bandwidth, to avoid attenuating the audio signal. Equation 9 provides this cutoff frequency, f . The value of R C FILT mustbechosenlargeenoughtominimizecurrentthatisshuntedfromtheload,yetsmallenoughtominimizethe attenuation of the analyzer-input voltage through the voltage divider formed by R and R . A rule of thumb is FILT ANA that R should be small (~100 Ω) for most measurements. This reduces the measurement error to less than FILT 1%forR ≥10kΩ. ANA (cid:3) RANA (cid:4) (cid:3)VOUT(cid:4) RANA(cid:1)RFILT (cid:2) VIN (cid:3) (cid:1) (cid:4) 1(cid:1)j (cid:1) O (8) fC(cid:2)(cid:3)2(cid:1)fMAX (9) An exception occurs with the efficiency measurements, where R must be increased by a factor of ten to FILT reduce the current shunted through the filter. C must be decreased by a factor of ten to maintain the same FILT cutofffrequency.SeeTable4fortherecommendedfiltercomponentvalues. Once f is determined and R is selected, the filter capacitance is calculated using Equation 9. When the C FILT calculatedvalueisnotavailable,itisbettertochooseasmallercapacitancevaluetokeepf abovetheminimum C desiredvaluecalculatedinEquation10. C (cid:2) 1 FILT 2(cid:1) (cid:1)f (cid:1)R C FILT (10) Table 4 shows recommended values of R and C based on common component values. The value of f FILT FILT C was originally calculated to be 28 kHz for an f of 20 kHz. C , however, was calculated to be 57,000 pF, but MAX FILT the nearest values of 56,000 pF and 51,000 pF were not available. A 47,000-pF capacitor was used instead, and f is34kHz,whichisabovethedesiredvalueof28kHz. C Table4.TypicalRCMeasurementFilterValues MEASUREMENT R C FILT FILT Efficiency 1000Ω 5,600pF Allothermeasurements 100Ω 56,000pF Copyright©2004–2010,TexasInstrumentsIncorporated SubmitDocumentationFeedback 23 ProductFolderLink(s):TPA3008D2

TPA3008D2 SLOS435C–MAY2004–REVISEDAUGUST2010 www.ti.com REVISION HISTORY ChangesfromRevisionB(November2004)toRevisionC Page • ReplacedtheDISSIPATIONRATINGTABLEwiththeThermalInformationTable ............................................................. 2 24 SubmitDocumentationFeedback Copyright©2004–2010,TexasInstrumentsIncorporated ProductFolderLink(s):TPA3008D2

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) TPA3008D2PHP ACTIVE HTQFP PHP 48 250 Green (RoHS NIPDAU Level-4-260C-72 HR -40 to 85 TPA3008D2 & no Sb/Br) TPA3008D2PHPG4 ACTIVE HTQFP PHP 48 250 Green (RoHS NIPDAU Level-4-260C-72 HR -40 to 85 TPA3008D2 & no Sb/Br) TPA3008D2PHPR ACTIVE HTQFP PHP 48 1000 Green (RoHS NIPDAU Level-4-260C-72 HR -40 to 85 TPA3008D2 & no Sb/Br) TPA3008D2PHPRG4 ACTIVE HTQFP PHP 48 1000 Green (RoHS NIPDAU Level-4-260C-72 HR -40 to 85 TPA3008D2 & 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 Addendum-Page 1

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

PACKAGE MATERIALS INFORMATION www.ti.com 26-Feb-2019 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) TPA3008D2PHPR HTQFP PHP 48 1000 330.0 16.4 9.6 9.6 1.5 12.0 16.0 Q2 PackMaterials-Page1

PACKAGE MATERIALS INFORMATION www.ti.com 26-Feb-2019 *Alldimensionsarenominal Device PackageType PackageDrawing Pins SPQ Length(mm) Width(mm) Height(mm) TPA3008D2PHPR HTQFP PHP 48 1000 350.0 350.0 43.0 PackMaterials-Page2

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