Pre-Production
WM8959
The input data source for each DAC can be changed under software control using register bits
DACL_SRC and DACR_SRC. The polarity of each DAC input may also be modified using register
bits DACL_DATINV and DACR_DATINV. These register bits are described in Table 14.
REGISTER
ADDRESS
BIT
15
LABEL
DEFAULT
DESCRIPTION
R5 (05h)
DACL_SRC
0b
Left DAC Data Source Select
0 = Left DAC outputs left channel data
1 = Left DAC outputs right channel data
Right DAC Data Source Select
0 = Right DAC outputs left channel data
1 = Right DAC outputs right channel data
Left DAC Invert
14
1
DACR_SRC
1b
0b
0b
R10 (0Ah)
DACL_DATINV
DACR_DATINV
0 = Left DAC output not inverted
1 = Left DAC output inverted
Right DAC Invert
0
0 = Right DAC output not inverted
1 = Right DAC output inverted
Table 14 DAC Routing and Control
DAC INTERFACE VOLUME BOOST
A digital gain function is available at the audio interface to boost the DAC volume when a small
signal is received on DACDAT. This is controlled using register bits DAC_BOOST[1:0]. To prevent
clipping at the DAC input, this function should not be used when the boosted DAC data is expected
to be greater than 0dBFS.
REGISTER
ADDRESS
BIT
LABEL
DEFAULT
DESCRIPTION
R5 (05h)
11:10
DAC_BOOST
[1:0]
00b
DAC Input Volume Boost
00 = 0dB
01 = +6dB (Input data must not
exceed -6dBFS)
10 = +12dB (Input data must not
exceed -12dBFS)
11 = +18dB (Input data must not
exceed -18dBFS)
Table 15 DAC Interface Volume Boost
PP, May 2008, Rev 3.1
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WOLFSON [ WOLFSON MICROELECTRONICS PLC ]
