wm8903 Wolfson Microelectronics plc, wm8903 Datasheet - Page 46

• Manufacturer Part Number: wm8903
• Description: Ultra Low Power Codec For Portable Audio Applications
• Manufacturer: Wolfson Microelectronics plc

WM8903
DIGITAL MIXING
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INITIALISATION
When the DRC is initialised, the gain is set to the level determined by the DRC_STARTUP_GAIN
register field. The default setting is 0dB, but values from -18dB to +36dB are available, as described
in Table 21.
Table 21 DRC Initialisation
The ADC and DAC data can be combined in various ways to support a range of different usage
modes.
Data from either of the two ADCs can be routed to either the left or the right channel of the digital
audio interface. In addition, data from either of the digital audio interface channels can be routed to
either the left or the right DAC. See “Digital Audio Interface” for more information on the audio
interface.
DIGITAL MIXING PATHS
Figure 31 shows the digital mixing paths available in the WM8903 digital core.
R40 (28h)
DRC 0
REGISTER
ADDRESS
10:6
BIT
DRC_STARTUP_
GAIN [4:0]
LABEL
DEFAULT
00110
Initial gain at DRC startup
00000 = -18dB
00001 = -15dB
00010 = -12dB
00011 = -9dB
00100 = -6dB
00101 = -3dB
00110 = 0dB (default)
00111 = 3dB
01000 = 6dB
01001 = 9dB
01010 = 12dB
01011 = 15dB
01100 = 18dB
01101 = 21dB
01110 = 24dB
01111 = 27dB
10000 = 30dB
10001 = 33dB
10010 = 36dB
10011 to 11111 = Reserved
PP, Rev 3.1, August 2009
DESCRIPTION
Pre-Production
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