Production Data
WM8350
12.1
GENERAL DESCRIPTION ............................................................................. 45
12.1.1
CLOCKING THE AUDIO CODEC........................................................................................46
12.1.2
12.1.3
CLOCKING THE DC-DC CONVERTERS............................................................................ 46
INTERNAL RC OSCILLATOR..............................................................................................46
12.2
12.3
CRYSTAL OSCILLATOR................................................................................ 46
CLOCKING AND SAMPLE RATES ................................................................ 47
12.3.1
12.3.2
12.3.3
12.3.4
12.3.5
12.3.6
SYSCLK CONTROL............................................................................................................. 49
ADC / DAC SAMPLE RATES............................................................................................... 50
BCLK CONTROL ................................................................................................................. 52
ADCLRCLK / DACLRCLK CONTROL .................................................................................54
OPCLK CONTROL ..............................................................................................................55
SLOWCLK CONTROL......................................................................................................... 55
12.4
FLL ................................................................................................................. 55
12.4.1
EXAMPLE FLL CALCULATION...........................................................................................58
12.4.2
EXAMPLE FLL SETTINGS ..................................................................................................59
13 AUDIO CODEC SUBSYSTEM.....................................................................60
13.1
13.2
13.3
13.4
GENERAL DESCRIPTION ............................................................................. 60
AUDIO PATHS ............................................................................................... 61
ENABLING THE AUDIO CODEC ................................................................... 62
INPUT SIGNAL PATH .................................................................................... 63
13.4.1
13.4.2
MICROPHONE INPUTS ...................................................................................................... 63
ENABLING THE PRE-AMPLIFIERS....................................................................................64
SELECTING INPUT SIGNALS.............................................................................................65
CONTROLLING THE PRE-AMPLIFIER GAINS...................................................................66
MICROPHONE BIASING.....................................................................................................67
AUXILIARY INPUTS (IN3L AND IN3R)................................................................................67
INPUT MIXERS....................................................................................................................69
13.4.3
13.4.4
13.4.5
13.4.6
13.4.7
13.5
ANALOGUE TO DIGITAL CONVERTER (ADC)............................................. 71
13.5.1
13.5.2
ADC VOLUME CONTROL...................................................................................................72
ADC HIGH-PASS FILTER....................................................................................................72
DIGITAL MIXING............................................................................................ 73
13.6
13.7
13.6.1
DIGITAL SIDETONE............................................................................................................ 73
DIGITAL TO ANALOGUE CONVERTER (DAC)............................................. 75
13.7.1
13.7.2
13.7.3
13.7.4
13.7.5
DAC PLAYBACK VOLUME CONTROL ...............................................................................76
DAC SOFT MUTE AND SOFT UN-MUTE............................................................................ 76
DAC DE-EMPHASIS............................................................................................................ 77
DAC OUTPUT PHASE AND MONO MIXING....................................................................... 78
DAC STOPBAND ATTENUATION.......................................................................................78
13.8
OUTPUT SIGNAL PATH ................................................................................ 79
13.8.1
13.8.2
13.9
ENABLING THE ANALOGUE OUTPUTS............................................................................ 79
OUTPUT MIXERS................................................................................................................ 80
ANALOGUE OUTPUTS.................................................................................. 83
13.9.1
13.9.2
13.9.3
13.9.4
OUT1L AND OUT1R............................................................................................................ 83
OUT2L AND OUT2R............................................................................................................ 85
HEADPHONE OUTPUTS EXTERNAL CONNECTIONS .....................................................87
OUT3 AND OUT4 ................................................................................................................ 89
13.10 DIGITAL AUDIO INTERFACE ........................................................................ 91
13.10.1 AUDIO DATA FORMATS.....................................................................................................91
13.10.2 AUDIO INTERFACE TDM MODE ........................................................................................94
13.10.3 TDM DATA FORMATS......................................................................................................... 94
13.10.4 LOOPBACK .........................................................................................................................96
13.11 COMPANDING............................................................................................... 97
13.12 ADDITIONAL CODEC FUNCTIONS............................................................... 99
13.12.1 HEADPHONE JACK DETECT.............................................................................................99
13.12.2 MICROPHONE DETECTION.............................................................................................100
PD, February 2011, Rev 4.4
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WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
