Production Data
WM8946
DIGITAL-TO-ANALOGUE CONVERTER (DAC)............................................................ 47
DAC DIGITAL VOLUME CONTROL..........................................................................................................47
DAC AUTO-MUTE.....................................................................................................................................50
DAC SLOPING STOPBAND FILTER ........................................................................................................50
DIGITAL BEEP GENERATOR ....................................................................................... 51
OUTPUT SIGNAL PATH................................................................................................ 52
OUTPUT SIGNAL PATHS ENABLE..........................................................................................................53
LINE OUTPUT MIXER CONTROL ............................................................................................................54
SPEAKER PGA MIXER CONTROL ..........................................................................................................56
SPEAKER PGA VOLUME CONTROL.......................................................................................................59
SPEAKER OUTPUT CONTROL................................................................................................................61
ANALOGUE OUTPUTS ................................................................................................. 62
LINE OUTPUTS.........................................................................................................................................62
SPEAKER OUTPUTS................................................................................................................................62
EXTERNAL COMPONENTS FOR LINE OUTPUT....................................................................................62
LDO REGULATOR......................................................................................................... 63
REFERENCE VOLTAGES AND MASTER BIAS ........................................................... 66
POP SUPPRESSION CONTROL .................................................................................. 68
DISABLED OUTPUT CONTROL...............................................................................................................68
OUTPUT DISCHARGE CONTROL ...........................................................................................................69
DIGITAL AUDIO INTERFACE........................................................................................ 69
MASTER AND SLAVE MODE OPERATION.............................................................................................69
AUDIO DATA FORMATS ..........................................................................................................................70
COMPANDING..........................................................................................................................................73
LOOPBACK...............................................................................................................................................76
DIGITAL PULL-UP AND PULL-DOWN......................................................................................................77
CLOCKING AND SAMPLE RATES................................................................................ 77
DIGITAL MIC CLOCKING .........................................................................................................................80
FREQUENCY LOCKED LOOP (FLL)........................................................................................................80
EXAMPLE FLL CALCULATION.................................................................................................................84
EXAMPLE FLL SETTINGS........................................................................................................................85
VIDEO BUFFER............................................................................................................. 86
RECOMMENDED VIDEO BUFFER INITIALISATION SEQUENCE..........................................................88
GENERAL PURPOSE INPUT/OUTPUT ........................................................................ 90
GPIO FUNCTION SELECT .......................................................................................................................93
INTERRUPTS ................................................................................................................ 94
CONTROL INTERFACE................................................................................................. 96
SELECTION OF CONTROL INTERFACE MODE.....................................................................................96
2-WIRE (I2C) CONTROL MODE...............................................................................................................97
3-WIRE (SPI) CONTROL MODE...............................................................................................................99
4-WIRE (SPI) CONTROL MODE.............................................................................................................100
PD, July 2012, Rev 4.3
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WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
