Preliminary Technical Data
WM8766
DAC DIGITAL VOLUME CONTROL
The DAC volume may also be adjusted in the digital domain using independent digital attenuation
control registers
REGISTER
ADDRESS
BIT
LABEL
DEFAULT
DESCRIPTION
0000000
7:0
LDA1[7:0]
11111111
(0dB)
Digital Attenuation data for Left channel DACL1 in 0.5dB steps. See
Table 10
Digital
Attenuation
DACL1
8
UPDATE
Not latched
Controls simultaneous update of all Attenuation Latches
0: Store LDA1 in intermediate latch (no change to output)
1: Store LDA1 and update attenuation on all channels
0000001
7:0
8
RDA1[6:0]
UPDATE
11111111
(0dB)
Digital Attenuation data for Right channel DACR1 in 0.5dB steps.
See Table 10.
Digital
Attenuation
DACR1
Not latched
Controls simultaneous update of all Attenuation Latches
0: Store RDA1 in intermediate latch (no change to output)
1: Store RDA1 and update attenuation on all channels.
0000100
7:0
8
LDA2[7:0]
UPDATE
11111111
(0dB)
Digital Attenuation data for Left channel DACL2 in 0.5dB steps. See
Table 10
Digital
Attenuation
DACL2
Not latched
Controls simultaneous update of all Attenuation Latches
0: Store LDA2 in intermediate latch (no change to output)
1: Store LDA2 and update attenuation on all channels.
0000101
7:0
8
RDA2[7:0]
UPDATE
11111111
(0dB)
Digital Attenuation data for Right channel DACR2 in 0.5dB steps.
See Table 10
Digital
Attenuation
DACR2
Not latched
Controls simultaneous update of all Attenuation Latches
0: Store RDA2 in intermediate latch (no change to output)
1: Store RDA2 and update attenuation on all channels.
0000110
7:0
8
LDA3[7:0]
UPDATE
11111111
(0dB)
Digital Attenuation data for Left channel DACL3 in 0.5dB steps. See
Table 10
Digital
Attenuation
DACL3
Not latched
Controls simultaneous update of all Attenuation Latches
0: Store LDA3 in intermediate latch (no change to output)
1: Store LDA3 and update attenuation on all channels.
0000111
7:0
8
RDA3[7:0]
UPDATE
11111111
(0dB)
Digital Attenuation data for Right channel DACR3 in 0.5dB steps.
See Table 10
Digital
Attenuation
DACR3
Not latched
Controls simultaneous update of all Attenuation Latches
0: Store RDA3 in intermediate latch (no change to output)
1: Store RDA3 and update attenuation on all channels.
0001000
7:0
8
MASTDA
[7:0]
11111111
(0dB)
Digital Attenuation data for all DAC channels in 0.5dB steps. See
Table 10
Master
Digital
Attenuation
UPDATE
Not latched
Controls simultaneous update of all Attenuation Latches
0: Store gain in intermediate latch (no change to output)
1: Store gain and update attenuation on all channels.
(all channels)
L/RDAX[7:0]
ATTENUATION LEVEL
00(hex)
-∞ dB (mute)
01(hex)
-127dB
:
:
:
:
:
:
FE(hex)
FF(hex)
-0.5dB
0dB
Table 10 Digital Volume Control Attenuation Levels
PTD Rev 2.3 February 2004
25
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