WM8711BL Wolfson Microelectronics, WM8711BL Datasheet - Page 14

• Manufacturer Part Number: WM8711BL
• Description: Ultra-Small Audio DAC
• Manufacturer: Wolfson Microelectronics

WM8711BL
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AUDIO SIGNAL PATH
DAC FILTERS
The DAC filters perform true 24 bit signal processing to convert the incoming digital audio data from
the digital audio interface at the specified sample rate to multi-bit oversampled data for processing by
the analogue DAC. Figure 6 illustrates the DAC digital filter path.
Figure 6 DAC Filter Schematic
The DAC digital filter can apply digital de-emphasis under software control, as shown in Table 2. The
DAC can also perform a soft mute where the audio data is digitally brought to a mute level. This
removes any abrupt step changes in the audio that might otherwise result in audible clicks in the
audio outputs.
Table 2 DAC Software Control
Note 1:
0000101
Digital Audio
Path Control
1. Not valid when SR[3:0] = 1111 or 0111.
2. To ensure correct DACMU operation at fs = 88.2kHz, set SR[3:0] = 1000.
3. To ensure correct DACMU operation at fs = 96kHz, set SR[3:0] = 0000.
REGISTER
FROM DIGITAL
ADDRESS
INTERFACE
AUDIO
2:1
3
BIT
DE_EMPHASIS
DEEMP
DIGITAL
DEEMP[1:0]
DACMU
LABEL
DACMU
MUTE
00
1
DEFAULT
INTERPOLATION
DIGITAL
FILTER
De-emphasis Control
(Digital)
11 = 48kHz
10 = 44.1kHz
01 = 32kHz
00 = Disable
DAC Soft Mute Control
(Digital)
1 = Enable soft mute
0 = Disable soft mute
Note 1
PD, Rev 4.1, April 2007
DESCRIPTION
OUTPUTS
TO LINE
Production Data
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