Datasheet

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ChannelStatusInformation(PCM2902)
CopyrightManagement(PCM2902)
INTERFACESEQUENCE
PowerOn,Attach,andPlaybackSequence
D+/D–
2.5V(Typ)
0V
InternalReset
ReadyforSetup
SOF
ReadyforPlayback
BusReset
SetConfiguration
SOF SOF
BPZ
BusIdle
5V (Typ)
1
AudioData
st
2 AudioData
nd
V (Pin3)
BUS
SSPND
V L
OUT
V
R
OUT
700 sm
DeviceSetup
1ms
T0055-02
PCM2900
PCM2902
SLES035E–MARCH2007–REVISEDMARCH2008
Thechannelstatusinformationisfixedasconsumerapplication,PCMmode,copyright,anddigital/digital
converter.Allotherbitsarefixedas0sexceptforthesamplefrequency,whichissetautomaticallyaccordingto
thedatareceivedthroughtheUSB.
Isochronous-indataisaffectedbytheserialcopymanagementsystem(SCMS).Wherereceivingdigitalaudio
datathatisindicatedasoriginaldatainthecontrolbit,inputdigitalaudiodatatransferstothehost.Ifthedatais
indicatedasfirstgenerationorhigher,transferreddataisselectedtoanaloginput.
DigitalaudiodataoutputisalwaysencodedasoriginalwithSCMScontrol.
Theimplementationofthisfeatureisanoptionforthecustomer.Notethatitistheuser'sresponsibilitywhether
theyimplementthisfeatureintheirproductornot.
ThePCM2900/2902isreadyforsetupwhentheresetsequencehasfinishedandtheUSBbusisattached.After
connectionhasbeenestablishedbysetup,thePCM2900/2902isreadytoacceptUSBaudiodata.Whilewaiting,
theaudiodata(idlestate)andanalogoutputaresettobipolarzero(BPZ).
Whenreceivingtheaudiodata,thePCM2900/2902storesthefirstaudiopacket,whichcontained1-msaudio
data,intotheinternalstoragebuffer.ThePCM2900/2902startsplayingtheaudiodatawhendetectingthe
followingstartofframe(SOF)packet.
Figure32.InitialSequence
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ProductFolderLink(s):PCM2900PCM2902
Not Recommended for New Designs