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ASINGLETHRESHOLDABOVEWHICHTHEGAINISREDUCED4HEAMOUNTOF
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ANDISDElNEDASD"CHANGEININPUTD"CHANGEINOUTPUT&OR
EXAMPLEIFTHEINPUTTOACOMPRESSORISINCREASEDBYD"
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THEABSO
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THEINTEGERPARTOFTHEEXPRESSION
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R
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THEINTEGERPARTOFTHEEXPRESSION
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THEPREDICTIVECOMPRESSORDELAYIN
ABSOLUTETIME
F
3
F
F
THEAUDIOSAMPLERATEANDTHEMAXIMUM
3
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VALUEIS
R
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WHERE
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R
GAINAND>THERAISETOTHEPOWER
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LEFTANDRIGHTINPUTSAA
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2IGHTWHEREAAAND
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MEMORY4HEADDRESSINTOTHEMEMORYWILLBEAUTOMATICALLY
INCREMENTEDFOREACHNEWWRITE4HISMODEISDOCUMENTEDINTHE
30)2EAD7RITE$ATA&ORMATSSECTIONOFTHISDATASHEET
/NCETHEDATAHASBEENWRITTENTHESHUTDOWNBITCANBECLEARED
$4HEPROCESSORTHENWILLINITIATEAVOLUMERAMPUPSEQUENCE
!$#
"
&IGURE2ECOMMENDED3EQUENCESFOR#OMPLETE0ARAMETEROR0ROGRAM2!-5PLOADED5SING3HUTDOWN-ECHANISM
REV. B
!$
n
n
./4%3
4HEDETECTORHOLDANDDECAYTIMESAREINTEGERVALUESWHILETHERESTOFTHEPARAMETERSAREFRACTIONALTWOSCOMPLEMENTVALUES
4HEDEFAULTDECAYTIMEOFTHEHOLDRELEASECIRCUITISSETFASTENOUGHSOTHATTHEDECAYISDOMINATEDBYTHETIMECONSTANTOFTHERMSDETECTOR
4ABLE6) 0ARAMETER2!-#ONTENTS$EFAULT0ROGRAM
))2,EFTB
))2,EFTB
))2,EFTB
))2,EFTA
))2,EFTA
))2,EFTB
))2,EFTB
))2,EFTB
))2,EFTA
))2,EFTA
))2,EFTB
))2,EFTB
))2,EFTB
))2,EFTA
))2,EFTA
))2,EFTB
))2,EFTB
))2,EFTB
))2,EFTA
))2,EFTA
))2,EFTB
))2,EFTB
))2,EFTB
))2,EFTA
))2,EFTA
))2,EFTB
))2,EFTB
))2,EFTB
))2,EFTA
))2,EFTA
))2,EFTB
))2,EFTB
))2,EFTB
))2,EFTA
))2,EFTA
))22IGHTB
))22IGHTB
))22IGHTB
))22IGHTA
))22IGHTA
))22IGHTB
))22IGHTB
))22IGHTB
))22IGHTA
))22IGHTA
))22IGHTB
))22IGHTB
))22IGHTB
))22IGHTA
))22IGHTA
))22IGHTB
))22IGHTB
))22IGHTB
))22IGHTA
$EFAULT6ALUE
IN&RACTIONAL
!DDR
&UNCTION
&ORMAT
))22IGHTA
))22IGHTB
))22IGHTB
))22IGHTB
))22IGHTA
))22IGHTA
))22IGHTB
))22IGHTB
))22IGHTB
))22IGHTA
))22IGHTA
))22IGHTB
))22IGHTB
))22IGHTB
))22IGHTA
))22IGHTA
))28OVER,EFTB
))28OVER,EFTB
))28OVER,EFTB
))28OVER,EFTA
))28OVER,EFTA
))28OVER,EFTB
))28OVER,EFTB
))28OVER,EFTB
))28OVER,EFTA
))28OVER,EFTA
))28OVER2IGHTB
))28OVER2IGHTB
))28OVER2IGHTB
))28OVER2IGHTA
))28OVER2IGHTA
))28OVER2IGHTB
))28OVER2IGHTB
))28OVER2IGHTB
))28OVER2IGHTA
))28OVER2IGHTA
))28OVER3UBB
))28OVER3UBB
))28OVER3UBB
))28OVER3UBA
))28OVER3UBA
))28OVER3UBB
))28OVER3UBB
))28OVER3UBB
))28OVER3UBA
))28OVER3UBA
))28OVER3UBB
))28OVER3UBB
))28OVER3UBB
))28OVER3UBA
))28OVER3UBA
))23UBRMSB
))23UBRMSB
))23UBRMSB
$EFAULT6ALUE
IN&RACTIONAL
!DDR
&UNCTION
&ORMAT
))23UBRMSA
))23UBRMSA
n
-AIN#OMPRESSOR
ALL
,OOK5P4ABLE"ASE
-AIN#OMPRESSOR
!TTACKRMS4IME
D"SEC
#ONSTANT
-AIN0OST
#OMPRESSOR'AIN
n
3UBWOOFER
#OMPRESSOR
,OOK5P4ABLE"ASE
3UB#OMPRESSOR
!TTACKRMS4IME
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#ONSTANT
0OST#OMPRESSOR
'AIN3UB
(IGH0ASS&ILTER
#UTOFF&REQUENCY
-AIN#OMPRESSOR
,OOK!HEAD$ELAY
$ELAY,EFT
$ELAY2IGHT
$ELAY3UB
3TEREO3PREADING
#OEFlCIENT
3TEREO3PREADING
&REQUENCY#ONTROL
3UBWOOFER
2EINJECTION
TO-AIN,EFT
3UBWOOFER
2EINJECTION
TO-AIN2IGHT
3UBWOOFER#HANNEL
)NPUT'AINFROM
,EFT)N
3UBWOOFER#HANNEL
)NPUT'AINFROM
2IGHT)N
-AIN$ETECTOR(OLD
4IME3AMPLES
-AX
3UB$ETECTOR(OLD
4IME3AMPLES
-AX
-AIN$ETECTOR
$ECAY4IME
D"SEC
3UB$ETECTOR
$ECAY4IME
D"SEC
n
5NUSED
$EFAULT6ALUE
IN&RACTIONAL
!DDR
&UNCTION
&ORMAT
REV. B
!$
n
n
THATLASTSFORMSTOMS!GAINTHISREDUCESTHECHANCEOF
ANYPOPORCLICKNOISEFROMOCCURRING
.OTETHATTHISSHUTDOWNSEQUENCEASSUMESTHATTHEPARTISSET
TOTHEFASTVOLUMERAMPSPEED#ONTROL2EGISTER"IT)FTHE
SLOWRAMPSPEEDISSETTHEVOLUMEMAYNOTREACHZEROBEFORETHE
PARTENTERSSHUTDOWNANDACLICKORPOPMAYBEHEARD
3AFELOAD-ECHANISM
-ANYAPPLICATIONSREQUIREREALTIMECONTROLOFlLTERCHARACTERISTICS
SUCHASBASSTREBLECONTROLSANDPARAMETRICORGRAPHICEQUALIZATION
4OPREVENTINSTABILITYFROMOCCURRINGALLOFTHEPARAMETERSOFA
PARTICULARBIQUADlLTERMUSTBEUPDATEDATTHESAMETIMEOTHER
WISETHElLTERCOULDEXECUTEFORONEORTWOAUDIOFRAMESWITHA
MIXTUREOFOLDANDNEWCOEFlCIENTS4HISMIXOFOLDANDNEW
COULDCAUSETEMPORARYINSTABILITYLEADINGTOTRANSIENTSTHATCOULD
TAKEALONGTIMETODECAY
4HEMETHODUSEDINTHE!$TOELIMINATETHISPROBLEMISTO
LOADASETOFlVEREGISTERSINTHE30)PORTWITHTHEDESIREDPARAM
ETER2!-ADDRESSANDDATA&IVEREGISTERSAREUSEDBECAUSEEACH
BIQUADlLTERHASlVECOEFlCIENTS/NCETHESEREGISTERSARELOADED
THEINITIATESAFETRANSFERBITIN#ONTROL2EGISTERSHOULDBESET
/NCETHISBITISSETTHEPROCESSORWAITSFORAPERIODOFTIMEIN
THEPROGRAMSEQUENCEWHERETHEPARAMETER2!-ISNOTBEING
ACCESSEDFORATLEASTlVECONSECUTIVEINSTRUCTIONCYCLES7HENTHE
PROGRAMCOUNTERREACHESTHISPOINTTHEPARAMETER2!-ISWRIT
TENWITHlVENEWDATAVALUESATADDRESSESCORRESPONDINGTOTHOSE
THATWEREENTEREDINTHESAFELOADREGISTERS7HENTHEOPERATIONIS
COMPLETE"ITOF#ONTROL2EGISTERREADISSET4HISBITMAY
BEPOLLEDBYTHEEXTERNALMICROPROCESSORUNTILAISREADAND
WILLBERESETONAREADOPERATION4HEPOLLINGOPERATIONISNOT
REQUIREDTHESAFELOADMECHANISMGUARANTEESTHATTHETRANSFERWILL
BECOMPLETEWITHINONEAUDIOFRAME
4HESAFELOADLOGICAUTOMATICALLYSENDSONLYTHOSESAFELOADREGISTERS
THATHAVEBEENWRITTENTOSINCETHELASTSAFELOADOPERATION&OR
EXAMPLEIFONLYTWOPARAMETERSARETOBESENTTHENITISNECES
SARYTOWRITETOONLYTWOOFTHElVESAFELOADREGISTERS7HENTHE
REQUESTSAFETRANSFERBITISASSERTEDONLYTHOSETWOREGISTERSWILL
BESENTTHEOTHERTHREEREGISTERSARENOTSENTANDCANSTILLHOLD
OLDORINVALIDDATA
4HESAFELOADMECHANISMISNOTLIMITEDTOUPLOADINGBIQUAD
COEFlCIENTSANYSETOFlVEVALUESINTHEPARAMETER2!-MAYBE
UPDATEDINTHESAMEWAY4HISALLOWSREALTIMEADJUSTMENTOFTHE
COMPRESSORLIMITERDELAYORSTEREOSPREADINGBLOCKS
3UMMARYOF2!--ODES
4ABLE6))SHOWSTHESIZESANDAVAILABLEMODESOFTHEPARAMETER
2!-ANDTHEPROGRAM2!-
30)2%!$72)4%$!4!&/2-!43
4HEREADWRITEFORMATSOFTHE30)PORTAREDESIGNEDTOBEBYTE
ORIENTED4HISALLOWSFOREASYPROGRAMMINGOFCOMMONMICROCON
TROLLERCHIPS4OlTINTOABYTEORIENTEDFORMATSAREAPPENDED
TOTHEDATAlELDSTOEXTENDTHEDATAWORDTOTHENEXTMULTIPLEOF
BITS&OREXAMPLEBITWORDSWRITTENTOTHE30)PARAMETER
2!-AREAPPENDEDWITHTWOLEADINGZEROESTOREACHBITS
BYTESANDBITWORDSWRITTENTOTHEPROGRAM2!-ARE
APPENDEDWITHlVEZEROSTOREACHBITSBYTES4HESEZERO
EXTENDEDDATAlELDSAREAPPENDEDTOABYTElELDCONSISTINGOFA
READWRITEBITANDABITADDRESS4HE30)PORTKNOWSHOWMANY
DATABYTESTOEXPECTBASEDONTHEADDRESSTHATISRECEIVEDINTHE
lRSTTWOBYTES
4HETOTALNUMBEROFBYTESFORASINGLELOCATION30)WRITECOMMAND
CANVARYFROMBYTESFORACONTROLREGISTERWRITETOBYTESFOR
APROGRAM2!-WRITE"LOCKWRITESMAYBEUSEDTOlLLCONTIGUOUS
LOCATIONSINPROGRAM2!-ORPARAMETER2!-
4HEREADANDWRITEFORMATSOFTHEPARAMETER2!-PROGRAM2!-
ANDREGISTERSAREDETAILEDIN4ABLES6)))TO8)8
4ABLE6))2EAD7RITE-ODES
30)!DDRESS
"URST-ODE
-EMORY
3IZE
2ANGE
2EAD
7RITE
!VAILABLE
7RITE-ODES
0ARAMETER2!-
n
9E S
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9E S
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9E S
9E S
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"YTE
"YTE
"YTE
"YTE
"YTE
2
O
!DDR;=
!DDR;=
0ARAM;=
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"YTE
"YTE
"YTE
"YTE
"YTE
2
O
!DDR;=
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"YTE
"YTE
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0ROG;=
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!$$2!$$2
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REV. B
!$
n
n
"YTE
"YTE
"YTE
"YTE
"YTE
"YTE
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"YTE
"YTE
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"YTE
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0ROG;=
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4ABLE8)) 30)#ONTROL2EGISTER7RITE&ORMAT
"YTE
"YTE
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2
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"YTE
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2
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!DDR;=
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0ROG#OUNT;=2EG3EL;=
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"YTE
"YTE
"YTE
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2
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0ROG#OUNT;=2EG3EL;=
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"YTE
"YTE
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2
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"YTE
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!$
n
n
).)4)!,):!4)/.
0OWER5P3EQUENCE
4HE!$HASABUILTINPOWERUPSEQUENCETHATINITIALIZESTHE
CONTENTSOFTHEINTERNAL2!-S$URINGTHISTIMETHECONTENTS
OFTHEINTERNALPROGRAMBOOT2/-ARECOPIEDTOTHEINTERNAL
PROGRAM2!-MEMORYANDLIKEWISETHE30)PARAMETER2!-IS
lLLEDWITHVALUESFROMITSASSOCIATEDBOOT2/-4HEDATAMEMO
RIESAREALSOCLEAREDDURINGTHISTIME
4HEBOOTSEQUENCELASTSFOR-#,+CYCLESANDSTARTSONTHE
RISINGEDGEOFTHE2%3%4"PIN3INCETHEBOOTSEQUENCEREQUIRES
ASTABLEMASTERCLOCKTHEUSERSHOULDAVOIDWRITINGTOORREADING
FROMTHE30)REGISTERSDURINGTHISPERIODOFTIME.OTETHATTHE
DEFAULTPOWERONSTATEOFTHEINTERNALCLOCKMODECIRCUITRYIS
F
3
F
F
ORABOUT-(ZFORNORMALAUDIOSAMPLERATES4HISMODE
BYPASSESALLTHEINTERNALCLOCKDOUBLERSANDALLOWSTHEEXTERNAL
MASTERCLOCKTODIRECTLYOPERATETHE$30CORE)FTHEEXTERNAL
MASTERCLOCKIS
F
3
F
F
THENTHEBOOTSEQUENCEWILLOPERATEAT
THISREDUCEDCLOCKRATEANDWILLTAKESLIGHTLYLONGERTOCOMPLETE
!FTERTHEBOOTSEQUENCEHASlNISHEDTHECLOCKMODESMAYBE
SETVIATHE30)PORT&OREXAMPLEIFTHEEXTERNALMASTERCLOCK
FREQUENCYIS
F
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CLOCKTHEBOOTSEQUENCEWOULDTAKE
F
3
F
F
CLOCKCYCLESTOCOMPLETEAFTERWHICHAN30)WRITECOULD
OCCURTOPUTTHE!$IN
F
3
F
F
MODE
4HEDEFAULTSTATEOFTHE-#,+INPUTSELECTORIS-#,+3INCE
THISINPUTSELECTORISCONTROLLEDUSINGTHE30)PORTANDTHE30)PORT
CANNOTBEWRITTENTOUNTILTHEBOOTSEQUENCEISCOMPLETETHERE
MUSTBEASTABLEMASTERCLOCKSIGNALPRESENTONTHE-#,+PINAT
STARTUP
3ETTINGTHE#LOCK-ODE
4HE!$CONTAINSACLOCKDOUBLERCIRCUITTHATISUSEDTOGENER
ATEANINTERNAL
F
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F
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F
3
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4HECLOCKMODEISSETBYWRITINGTO"ITOF#ONTROL2EGISTER
7HENTHECLOCKMODEISCHANGEDITISPOSSIBLETHATAGLITCHWILL
OCCURONTHEINTERNAL-#,+SIGNAL4HISMAYCAUSETHEPROCES
SORTOINADVERTENTLYWRITEANINCORRECTVALUEINTOTHEDATA2!-
WHICHCOULDCAUSEANAUDIOPOPORCLICKSOUND4OPREVENTTHIS
THEFOLLOWINGPROCEDUREISRECOMMENDED
!SSERTTHESOFTPOWERDOWNBIT"ITIN#ONTROL2EGISTERTO
STOPTHEINTERNAL-#,+
7RITETHEDESIREDCLOCKMODEINTO"ITOF#ONTROL2EGISTER
7AITATLEASTMSWHILETHECLOCKDOUBLERSSETTLE
$EASSERTTHESOFTPOWERDOWNBIT
!NALTERNATIVEPROCEDUREISTOINITIATEASOFTSHUTDOWNOFTHEPRO
CESSORCOREBYWRITINGATOTHEHALTPROGRAMBITIN#ONTROL
2EGISTER4HISINITIATESAVOLUMERAMPDOWNSEQUENCEFOLLOWED
BYASHUTDOWNOFTHE$30CORE/NCETHECOREISSHUTDOWNWHICH
CANBEVERIlEDBYREADING"ITFROM#ONTROL2EGISTERORBY
WAITINGATLEASTMSTHENEWCLOCKMODECANBEPROGRAMMED
BYWRITINGTO"ITOF#ONTROL2EGISTER4HE$30CORECANTHEN
BERESTARTEDBYCLEARINGTHEHALTPROGRAMBITIN#ONTROL2EGISTER
3ETTINGTHE$ATAAND-#,+)NPUT3ELECTORS
4HE!$CONTAINSINPUTSELECTORSFORBOTHSERIALDATAINPUTS
ANDTHE-#,+INPUT4HISALLOWSTHE!$TOSELECTAVARIETY
OFINPUTANDCLOCKSOURCESWITHNOEXTERNALHARDWAREREQUIRED
4HESEINPUTSELECTORSARECONTROLLEDBYWRITINGTO30)#ONTROL
2EGISTER
7HENTHEDATASOURCEOR-#,+SOURCEISCHANGEDBYWRITING
TOTHE30)PORTITISPOSSIBLETHATAPOPORCLICKWILLOCCURINTHE
AUDIO4OPREVENTTHISNOISETHECORESHOULDBESHUTDOWNBY
WRITINGATOTHEHALTPROGRAMBITIN#ONTROL2EGISTER4HIS
INITIATESAVOLUMERAMPDOWNSEQUENCEFOLLOWEDBYASHUTDOWN
OFTHE$30CORE/NCETHECOREISSHUTDOWNWHICHCANBEVERI
lEDBYREADING"ITFROM#ONTROL2EGISTERORBYWAITINGAT
LEASTMSAFTERTHEHALTPROGRAMCOMMANDISISSUEDTHENEW
DATAOR-#,+SOURCECANBEPROGRAMMEDBYWRITINGTO#ONTROL
2EGISTER4HE$30CORECANTHENBERESTARTEDBYCLEARINGTHE
HALTPROGRAMBITIN#ONTROL2EGISTER
$!4!#!0452%2%')34%23
4HE!$INCORPORATESAFEATURECALLEDDATACAPTURE5SING
THISFEATUREANYNODEINTHESIGNALPROCESSINGmOWMAYBESENT
TOEITHERAN30)READABLEREGISTERORADEDICATEDSERIALOUTPUT
PIN4HISALLOWSTHEBASICFUNCTIONALITYOFTHE!$TOBE
EXTENDEDTOALARGERNUMBEROFCHANNELS!LTERNATIVELYITCANBE
USEDTOMONITORANDDISPLAYINFORMATIONABOUTSIGNALLEVELSOR
COMPRESSORLIMITERACTIVITY
4HE!$CONTAINSFOURINDEPENDENTDATACAPTUREREGISTERS
4WOOFTHESEREGISTERSTRANSFERTHEIRDATATOTHEDATACAPTURESERIAL
OUTPUT$#3/54PIN4HESERIALDATAFORMATOFTHISPINISTHE
SAMEASTHESERIALDATAFORMATUSEDFORTHEMAINDIGITALINPUTS
ANDTHE,2#,+AND"#,+SIGNALSCANTHEREFOREBEUSEDAS
FRAMESYNCANDBITCLOCKSIGNALS4HISPINISPRIMARILYINTENDED
TOFEEDSIGNALSTOANEXTERNAL$!#OR$30CHIPTOEXTENDTHE
NUMBEROFCHANNELSTHATTHEINTERNAL$30CANACCESS4HEOTHER
TWOREGISTERSMAYBEREADBACKOVERTHE30)PORTANDCANBEUSED
FORAVARIETYOFPURPOSES/NEEXAMPLEMIGHTBETOACCESSTHED"
OUTPUTOFTHEINTERNALRMSDETECTORTORUNAFRONTPANELSIGNAL
LEVELDISPLAY!SAMPLESYSTEMISSHOWNIN&IGURE&OREACH
OFTHEFOURDATACAPTUREREGISTERSACAPTURECOUNTANDAREGISTER
SELECTMUSTBESET4HECAPTURECOUNTISANUMBERBETWEENAND
THATCORRESPONDSTOTHEPROGRAMSTEPNUMBERWHERETHE
CAPTUREWILLOCCUR4HEREGISTERSELECTlELDPROGRAMSONEOFFOUR
REGISTERSINTHE$30CORETHATWILLBETRANSFERREDTOTHEDATACAP
TUREREGISTERWHENTHEPROGRAMCOUNTEREQUALSTHECAPTURECOUNT
4HEREGISTERSELECTlELDISDECODEDASFOLLOWS
-ULTIPLIER/UTPUT-ULT?/UT
/UTPUTOFD"#ONVERSION"LOCK$"?/54
-ULTIPLIER$ATA)NPUT-$)
-ULTIPLIER#OEFlCIENT)NPUT-#)
4HECAPTURECOUNTANDREGISTERSELECTBITSARESETBYWRITINGTOONE
OFTHEFOURDATACAPTUREREGISTERSATTHEFOLLOWING30)ADDRESSES
30)$ATA#APTURE3ETUP2EGISTER
30)$ATA#APTURE3ETUP2EGISTER
$ATA#APTURE3ERIAL/UT3ETUP2EGISTER
$ATA#APTURE3ERIAL/UT3ETUP2EGISTER
REV. B
!$
n
n
4HEFORMATOFTHECAPTUREDDATAVARIESACCORDINGTOTHEREGISTER
SELECTlELDS$ATACAPTUREDFROMTHEMULT?OUTSETTINGISIN
TWOSCOMPLEMENTFORMATSOTHATAFULLSCALEINPUTSIGNALWILL
PRODUCEAFULLSCALEDIGITALOUTPUTASSUMINGNOPROCESSING)F
THEPARAMETERSARESETSUCHTHATTHEINPUTTOOUTPUTGAINISMORE
THAND"THENTHEDIGITALOUTPUTWILLBECLIPPED
$ATACAPTUREDFROMTHE
$"?/54
SETTINGISINFORMATWHERE
4
THEACTUALRMSD"LEVELISEQUALTOn
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EQUATION
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4
THISDATAFORMATTHEACTUALOUTPUTREADINGSWILLRANGEFROMnD"
TOD"4HE!$USESTHECONVENTIONTHATD"ISTHERMS
VALUEOFTHEFULLSCALEDIGITALSIGNAL
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DIGITALINPUTWILLPRODUCEAnD"DIGITALOUTPUTASSUMINGTHE
!$ISSETFORNOPROCESSING
$ATACAPTUREDUSINGTHE-#)SETTINGISINFORMAT4HISDATA
ISGENERALLYASIGNALGAINORlLTERCOEFlCIENTANDTHEREFOREITDOES
NOTMAKESENSETOTALKABOUTTHEINPUTTOOUTPUTGAIN!COEFl
CIENTOFCORRESPONDSTOAGAINOF
4HEDATATHATMUSTBEWRITTENTOSETUPTHEDATACAPTUREISA
CONCATENATIONOFTHEBITPROGRAMCOUNTINDEXWITHTHEBIT
REGISTERSELECTlELD2EFERTO4ABLE88TOlNDTHECAPTURECOUNT
ANDREGISTERSELECTNUMBERSTHATCORRESPONDTOTHEDESIREDPOINT
TOBEMONITOREDINTHEDEFAULTSIGNALPROCESSINGmOW
4HE30)CAPTUREREGISTERSCANBEACCESSEDBYREADINGFROM30)
,OCATIONSFOR30)#APTURE2EGISTERORFOR30)#AP
TURE2EGISTER4HEOTHERTWODATACAPTUREREGISTERSDATACAPTURE
SERIALOUTAUTOMATICALLYTRANSFERTHEIRDATATOTHEDATACAPTURE
SERIALOUT$#3/54PIN$#3/54#APTURE2EGISTERISPRES
ENTINTHELEFTDATASLOTASDElNEDBYTHESERIALINPUTFORMATAND
$#3/54#APTURE2EGISTERISPRESENTINTHERIGHTDATASLOT4HE
FORMATFORWRITINGTOTHE30)DATACAPTURESETUPREGISTERSISGIVEN
INTHE30)SECTIONOFTHISDATASHEET
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REV. B
!$
n
n
4ABLE88$ATA#APTURE4RAP)NDEXESAND2EGISTER3ELECT$EFAULT0ROGRAM
0ROGRAM#OUNT
2EGISTER
3IGNAL$ESCRIPTION
)NDEX"ITS
3ELECT"ITS
.UMERIC&ORMAT
(0&/UT,EFT
-ULT?/UT
#LIPPED
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#LIPPED
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-ULT?/UT
#LIPPED
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#LIPPED
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#LIPPED
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#LIPPED
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#LIPPED
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#LIPPED
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#LIPPED
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#LIPPED
2IGHT"IQUAD/UTPUT
-ULT?/UT
#LIPPED
2IGHT"IQUAD/UTPUT
-ULT?/UT
#LIPPED
2IGHT"IQUAD/UTPUT
-ULT?/UT
#LIPPED
2IGHT"IQUAD/UTPUT
-ULT?/UT
#LIPPED
2IGHT"IQUAD/UTPUT
-ULT?/UT
#LIPPED
2IGHT"IQUAD/UTPUT
-ULT?/UT
#LIPPED
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-ULT?/UT
#LIPPED
6OLUME/UT,EFT
-ULT?/UT
#LIPPED
6OLUME/UT2IGHT
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#LIPPED
6OLUME/UT3UB
-ULT?/UT
#LIPPED
0HAT3TEREO/UT,EFT
-ULT?/UT
#LIPPED
0HAT3TEREO/UT2IGHT
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#LIPPED
$ELAY/UTPUT,EFT
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#LIPPED
Left Xover Biquad 0 Output
99
Mult_Out
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Left Xover Biquad 1 Output
108
Mult_Out
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Right Xover Biquad 0 Output
349
Mult_Out
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Right Xover Biquad 1 Output
358
Mult_Out
1.23, Clipped
Sub Delay Output
511
Mult_Out
1.23, Clipped
Sub rms Biquad Output
467
Mult_Out
1.23, Clipped
Sub rms Output (dB)
489
DB_Out
24-Bit Positive Binary, Bit 19
Corresponds to a 3 dB Change
Sub Compressor Gain (Linear)
495
MCI
2.22, 2 LSBs = 0
Subchannel Output
511
Mult_Out
1.23, Clipped
REV. B
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REV. B
AD1954
Rev. B | Page 33
OUTLINE DIMENSIONS
COM P LI AN T TO JE D EC S TANDARDS MS - 022-AB-1
041807-A
13.45
13.20 SQ
12.95
0.45
0.29
2.45
MAX
1.03
0.88
0.73
TOP VIEW
(PINS DOWN)
12
44
1
22
23
34
33
11
0.25
0.10
2.20
2.00
1.80
7°
0°
VIEW A
ROTATED 90° CCW
0.23
0.11
10.20
10.00 SQ
9.80
0.80 BSC
LE AD P IT C H LE AD W I DTH
0.10
COPLANARITY
VIEW A
SEATING
PLANE
1.60 REF
PIN 1
Figure 25. 44-Lead Metric Quad Flat Package [MQFP]
(S-44-1)
Dimensions shown in millimeters
COM P LI ANT TO JE DEC STANDARDS MS-0 26- BBC
TOP VIEW
(PINS DOWN)
1
12 13 25
24
36
37
48
0.27
0.22
0.17
0.50
BSC
LEAD PITCH
1.60
MAX
0.75
0.60
0.45
VIEW A
PIN 1
0.20
0.09
1.45
1.40
1.35
0.08
COPLANARITY
VIEW A
ROTATE D 90 ° CCW
SEATING
PLANE
7°
3.5°
0°
0.15
0.05
9.20
9.00 SQ
8.80
7.20
7.00 SQ
6.80
051706-A
Figure 26. 48-Lead Low Profile Quad Flat Package [LQFP]
(ST-48)
Dimensions shown in millimeters
ORDERING GUIDE
Model1 Temperature Range Package Description Package Option
AD1954YSZ –40°C to +105°C 44-Lead MQFP S-44-1
AD1954YSTZ –40°C to +105°C 48-Lead LQFP ST-48
AD1954YSTZRL –40°C to +105°C 48-Lead LQFP, 13" Tape and Reel ST-48
1 Z = RoHS Compliant Part.
AD1954
Rev. B | Page 34
REVISION HISTORY
12/14—Rev. A to Rev. B
Changes to Signal Processing Overview Section ....................... 12
Changes to Graphical Custom Programming Tools Section .... 31
Updated Outline Dimensions ....................................................... 33
Changes to Ordering Guide .......................................................... 33
8/03—Rev. 0 to Rev. A
Changes to Specifications ................................................................ 3
Changes to Absolute Maximum Ratings ....................................... 6
Changes to Ordering Guide ............................................................ 6
Change to TPCs 1 and 2 .................................................................. 8
Change to Main Compressor/Limiter Section ........................... 15
Change to Interpolation Filters Section ....................................... 18
Replaced Control Register 1 Section ............................................ 20
Changes to Control Register 2 Section ........................................ 21
Changes to Parameter RAM Contents Section .......................... 22
Change to Table VI ......................................................................... 23
Change to Table IX ......................................................................... 24
Change to Table XI ......................................................................... 25
Change to Data Capture Registers Section ................................. 26
Change to Table XX ........................................................................ 28
Change to Analog Output Section ............................................... 30
Reversed Figures 22 and 23 ........................................................... 30
Added Figure 24 .............................................................................. 30
Updated Outline Dimensions ....................................................... 33
©2014 Analog Devices, Inc. All rights reserved. Trademarks and
registered trademarks are the property of their respective owners.
D02760-0-12/14(B)
