wm8918 Wolfson Microelectronics plc, wm8918 Datasheet - Page 46

• Manufacturer Part Number: wm8918
• Description: Ultra Low Power Dac For Portable Audio Applications
• Manufacturer: Wolfson Microelectronics plc

WM8918
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The “knee” in Figure 29 is represented by register fields DRC_KNEE_IP and DRC_KNEE_OP.
Parameter Y0, the output level for a 0dB input, is not specified directly, but can be calculated from
the other parameters, using the equation
The DRC Compression parameters are defined in Table 14.
Table 14 DRC Compression Control
R43 (2Bh)
DRC Control 3
R42 (2Ah)
DRC Control 2
REGISTER
ADDRESS
10:5
BIT
4:0
5:3
2:0
DRC_LO_COMP
DRC_KNEE_OP
DRC_HI_COMP
DRC_KNEE_IP
LABEL
[5:0]
[4:0]
[2:0]
[2:0]
DEFAULT
00_0000
0_0000
000
000
Input signal at the Compressor
'knee'.
000000 = 0dB
000001 = -0.75dB
000010 = -1.5dB
… (-0.75dB steps)
111100 = -45dB
111101 to 111111 = Reserved
Output signal at the Compressor
'knee'.
00000 = 0dB
00001 = -0.75dB
00010 = -1.5dB
… (-0.75dB steps)
11110 = -22.5dB
11111 = Reserved
Compressor slope (upper region)
000 = 1 (no compression)
001 = 1/2
010 = 1/4
011 = 1/8
100 = 1/16
101 = 0
110 to 111 = Reserved
Compressor slope (lower region)
000 = 1 (no compression)
001 = 1/2
010 = 1/4
011 = 1/8
100 = 0
101 to 111 = Reserved
PD, Rev 4.0, September 2010
DESCRIPTION
Production Data
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