WM8731_WM8731L

wWM8731/WM8731LPortableInternetAudioCODECwithHeadphoneDriverandProgrammableSampleRatesWOLFSONMICROELECTRONICSplc2004WolfsonMicroelectronicsplcDESCRIPTIONTheWM8731orWM8731L(WM8731/L)arelowpowerstereoCODECswithanintegratedheadphonedriver.TheWM8731/LisdesignedspecificallyforportableMP3audioandspeechplayersandrecorders.TheWM8731isalsoidealforMD,CD-RWmachinesandDATrecorders.Stereolineandmonomicrophonelevelaudioinputsareprovided,alongwithamutefunction,programmablelinelevelvolumecontrolandabiasvoltageoutputsuitableforanelectrettypemicrophone.Stereo24-bitmulti-bitsigmadeltaADCsandDACsareusedwithoversamplingdigitalinterpolationanddecimationfilters.Digitalaudioinputwordlengthsfrom16-32bitsandsamplingratesfrom8kHzto96kHzaresupported.Stereoaudiooutputsarebufferedfordrivingheadphonesfromaprogrammablevolumecontrol,lineleveloutputsarealsoprovidedalongwithanti-thumpmuteandpowerup/downcircuitry.Thedeviceiscontrolledviaa2or3wireserialinterface.Theinterfaceprovidesaccesstoallfeaturesincludingvolumecontrols,mutes,de-emphasisandextensivepowermanagementfacilities.Thedeviceisavailableinasmall28-pinSSOPpackageorthesmaller28leadquadflatleadlesspackage(QFN).FEATURES•HighlyEfficientHeadphoneDriver•AudioPerformance-ADCSNR90dB(‘A’weighted)at3.3V,85dBat1.8V-DACSNR100dB(‘A’weighted)at3.3V,95dBat1.8V•LowPower-Playbackonly22mW,8mW(‘L’Variant)-AnaloguePassThrough12mW,3.5mW(‘L’variant)-1.42–3.6VDigitalSupplyOperation-2.7–3.6VAnalogueSupplyOperation-1.8–3.6VAnalogueSupplyOperation(‘L’Variant)•ADCandDACSamplingFrequency:8kHz–96kHz•SelectableADCHighPassFilter•2or3-WireMPUSerialControlInterface•ProgrammableAudioDataInterfaceModes-I2S,Left,RightJustifiedorDSP-16/20/24/32bitWordLengths-MasterorSlaveClockingMode•MicrophoneInputandElectretBiaswithSideToneMixer•Availablein28-PinSSOPor28-pinQFNpackageAPPLICATIONS•PortableMP3PlayersandRecorders•CDandMinidiscRecorders•PDAs/smartphonesBLOCKDIAGRAMMUXMUXVOLVOLADCADCDIGITALFILTERSDIGTALAUDIOINTERFACECONTROLINTERFACEDACDACVOL/MUTEVOL/MUTEH/PDRIVERH/PDRIVERCSBSDINSCLKΣΣRHPOUTLHPOUTROUTLOUTRLINEINLLINEINVMIDDBVDDDGNDAVDDAGND0dB/20dBMICIN+12to-34.5dB,1.5dBStepsCLKOUT+6to-73dB1dBStepsHPVDDHPGND+6to-73dB1dBStepsDCVDDADCLRCDACLRCBCLKDACDATADCDATOSCXTI/MCLKXTOMODEMICBIASMUTEBypassBypassCLKINDIVIDER(Divx1,x2)CLKOUTDIVIDER(Divx1,x2)ATTEN/MUTEMUTEMUTEATTEN/MUTEMUTEMUTEMUTEMUTEMUTE+12to-34.5dB,1.5dBStepsSideToneSideToneWWM8731WM8731/WM8731LProductionDatawPDRev3.4April20042TABLEOFCONTENTSDESCRIPTION.......................................................................................................1FEATURES.............................................................................................................1APPLICATIONS.....................................................................................................1BLOCKDIAGRAM.................................................................................................1PINCONFIGURATION-28PINSSOP.................................................................3ORDERINGINFORMATION..................................................................................3PINCONFIGURATION–28PINQFN...................................................................4ORDERINGINFORMATION..................................................................................4PINDESCRIPTION................................................................................................5ABSOLUTEMAXIMUMRATINGS.........................................................................6RECOMMENDEDOPERATINGCONDITIONS–WM8731...................................6RECOMMENDEDOPERATINGCONDITIONS–WM8731L.................................6ELECTRICALCHARACTERISTICS–WM8731....................................................7TERMINOLOGY.....................................................................................................9POWERCONSUMPTION–WM8731..................................................................10ELECTRICALCHARACTERISTICS–WM8731L................................................11TERMINOLOGY...................................................................................................12POWERCONSUMPTION–WM8731L................................................................12MASTERCLOCKTIMING....................................................................................13DIGITALAUDIOINTERFACE–MASTERMODE.......................................................14DIGITALAUDIOINTERFACE–SLAVEMODE..........................................................15MPUINTERFACETIMING..........................................................................................16DEVICEDESCRIPTION.......................................................................................18INTRODUCTION.........................................................................................................18AUDIOSIGNALPATH.................................................................................................19DEVICEOPERATION.