WM8770
Production Data
REGISTER
ADDRESS
BIT
LABEL
DEFAULT
DESCRIPTION
01111
7:0
LDA4[7:0]
11111111
(0dB)
Digital Attenuation data for Left channel DACL4 in 0.5dB steps. See
Table 12
Digital
Attenuation
DACL4
8
UPDATE
Not latched
Controls simultaneous update of all Attenuation Latches
0: Store LDA4 in intermediate latch (no change to output)
1: Store LDA4 and update attenuation on all channels.
10000
7:0
8
RDA4[7:0]
UPDATE
11111111
(0dB)
Digital Attenuation data for Right channel DACR4 in 0.5dB steps.
See Table 12
Digital
Attenuation
DACR4
Not latched
Controls simultaneous update of all Attenuation Latches
0: Store RDA4 in intermediate latch (no change to output)
1: Store RDA4 and update attenuation on all channels.
10001
7:0 MASTDA[7:0]
11111111
(0dB)
Digital Attenuation data for all DAC channels in 0.5dB steps. See
Table 12
Master
Digital
Attenuation
8
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)
-127.5dB
:
:
:
:
:
:
FE(hex)
FF(hex)
-0.5dB
0dB
Table 12 Digital Volume Control Attenuation Levels
The Digital volume control also incorporates a zero cross detect circuit which detects a transition
through the zero point before updating the digital volume control with the new volume. This is
enabled by control bit DZCEN.
REGISTER ADDRESS
10011
BIT
LABEL
DEFAULT
DESCRIPTION
0
DZCEN
0
DAC Digital Volume Zero Cross
Enable:
DAC Control
0: Zero cross detect disabled
1: Zero cross detect enabled
PD Rev 4.1 June 2005
34
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WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
