Cirrus Logic WM8940 Manual page 4

MINIMUM AND MAXIMUM GAIN .................................................................................................................................................. 35
ALC HOLD TIME (NORMAL MODE ONLY) .................................................................................................................................. 36
PEAK LIMITER .............................................................................................................................................................................. 38
NOISE GATE (NORMAL MODE ONLY) ....................................................................................................................................... 39
OUTPUT SIGNAL PATH .......................................................................................................... 41
DIGITAL HI-FI DAC VOLUME CONTROL .................................................................................................................................... 41
HI-FI DIGITAL TO ANALOGUE CONVERTER (DAC) .................................................................................................................. 42
AUTOMUTE ................................................................................................................................................................................... 42
DAC OUTPUT LIMITER ................................................................................................................................................................ 42
VOLUME BOOST .......................................................................................................................................................................... 43
ANALOGUE OUTPUTS ........................................................................................................... 45
SPKOUTP/SPKOUTN OUTPUTS ................................................................................................................................................. 45
ZERO CROSS TIMEOUT .............................................................................................................................................................. 46
MONO MIXER AND OUTPUT ....................................................................................................................................................... 47
ENABLING THE OUTPUTS .......................................................................................................................................................... 47
UNUSED ANALOGUE INPUTS/OUTPUTS .................................................................................................................................. 48
OUTPUT SWITCH ................................................................................................................... 49
THERMAL SHUTDOWN ............................................................................................................................................................... 49
SPEAKER OUTPUT ...................................................................................................................................................................... 49
HEADPHONE OUTPUT ................................................................................................................................................................ 50
MONO OUTPUT ............................................................................................................................................................................ 50
DIGITAL AUDIO INTERFACES ............................................................................................... 51
MASTER AND SLAVE MODE OPERATION ................................................................................................................................. 51
AUDIO DATA FORMATS .............................................................................................................................................................. 51
AUDIO INTERFACE CONTROL ................................................................................................................................................... 53
LOOPBACK ................................................................................................................................................................................... 55
AUDIO SAMPLE RATES ......................................................................................................... 55
MASTER CLOCK AND PHASE LOCKED LOOP (PLL) ........................................................... 55
INTEGER N DIVISION................................................................................................................................................................... 57
FRACTIONAL K MODE ................................................................................................................................................................. 57
EXAMPLE PLL CONFIGURATION: .............................................................................................................................................. 57
COMPANDING ......................................................................................................................... 58
GENERAL PURPOSE INPUT/OUTPUT .................................................................................. 60
CONTROL INTERFACE .......................................................................................................... 61
SELECTION OF CONTROL MODE AND 2-WIRE MODE ADDRESS .......................................................................................... 61
USE OF MODE AS A GPIO PIN IN 3-WIRE MODE ..................................................................................................................... 61
3-WIRE SERIAL CONTROL MODE .............................................................................................................................................. 62
READBACK IN 3-WIRE MODE ..................................................................................................................................................... 62
2-WIRE SERIAL CONTROL MODE .............................................................................................................................................. 63
RESETTING THE CHIP ........................................................................................................... 63
POWER SUPPLIES ................................................................................................................. 64
RECOMMENDED POWER UP/DOWN SEQUENCE .................................................................................................................... 64
POWER MANAGEMENT ......................................................................................................... 66
VMID .............................................................................................................................................................................................. 66
BIASEN .......................................................................................................................................................................................... 66
ESTIMATED SUPPLY CURRENTS .............................................................................................................................................. 66
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WM8940
Rev 4.4