Pre Production
WM8941
TABLE OF CONTENTS
DESCRIPTION ................................................................................................................1
FEATURES......................................................................................................................1
APPLICATIONS ..............................................................................................................1
BLOCK DIAGRAM ..........................................................................................................2
PIN CONFIGURATION....................................................................................................5
ORDERING INFORMATION ...........................................................................................5
PIN DESCRIPTION .........................................................................................................6
ABSOLUTE MAXIMUM RATINGS..................................................................................7
RECOMMENDED OPERATING CONDITIONS ..............................................................7
ELECTRICAL CHARACTERISTICS ...............................................................................8
TERMINOLOGY....................................................................................................................10
AUDIO PATHS OVERVIEW..........................................................................................12
SIGNAL TIMING REQUIREMENTS..............................................................................14
SYSTEM CLOCK TIMING .....................................................................................................14
AUDIO INTERFACE TIMING – MASTER MODE ..................................................................14
AUDIO INTERFACE TIMING – SLAVE MODE......................................................................15
CONTROL INTERFACE TIMING – 3-WIRE MODE ..............................................................16
CONTROL INTERFACE TIMING – 2-WIRE MODE ..............................................................17
DEVICE DESCRIPTION................................................................................................18
INTRODUCTION...................................................................................................................18
INPUT SIGNAL PATH...........................................................................................................19
ANALOGUE TO DIGITAL CONVERTER (ADC)....................................................................25
INPUT LIMITER / AUTOMATIC LEVEL CONTROL (ALC) ....................................................30
OUTPUT SIGNAL PATH .......................................................................................................43
VOLUME BOOST..................................................................................................................45
ANALOGUE OUTPUTS.........................................................................................................47
OUTPUT SWITCH ................................................................................................................50
VIDEO BUFFER....................................................................................................................53
DIGITAL AUDIO INTERFACES.............................................................................................58
AUDIO SAMPLE RATES.......................................................................................................62
MASTER CLOCK AND PHASE LOCKED LOOP (PLL).........................................................63
COMPANDING......................................................................................................................66
GENERAL PURPOSE INPUT/OUTPUT................................................................................68
CONTROL INTERFACE........................................................................................................68
3-WIRE SERIAL CONTROL MODE ......................................................................................70
READBACK IN 3-WIRE MODE .............................................................................................70
2-WIRE SERIAL CONTROL MODE ......................................................................................71
RESETTING THE CHIP ........................................................................................................71
POWER SUPPLIES ..............................................................................................................71
POWER MANAGEMENT ......................................................................................................74
POP MINIMISATION .............................................................................................................75
REGISTER MAP............................................................................................................76
REGISTER BITS BY ADDRESS ...........................................................................................77
DIGITAL FILTER CHARACTERISTICS........................................................................89
TERMINOLOGY....................................................................................................................89
DAC FILTER RESPONSES...................................................................................................90
ADC FILTER RESPONSES...................................................................................................90
HIGHPASS FILTER...............................................................................................................91
NOTCH FILTERS AND LOW PASS FILTER.........................................................................92
PP, Rev 3.3, December 2007
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WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
