wm8903 Wolfson Microelectronics plc, wm8903 Datasheet - Page 42

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

WM8903
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Table 15 DRC Compression Control
GAIN LIMITS
The minimum and maximum gain applied by the DRC is set by register fields DRC_MINGAIN and
DRC_MAXGAIN. These limits can be used to alter the DRC response from that illustrated in Figure
30. If the range between maximum and minimum gain is reduced, then the extent of the dynamic
range control is reduced. The maximum gain prevents quiet signals (or silence) from being
excessively amplified.
R42 (2Ah)
DRC 2
R43 (2Bh)
DRC 3
REGISTER
ADDRESS
10:5
BIT
5:3
2:0
4:0
DRC_R0_SLOP
E_COMP [2:0]
DRC_R1_SLOP
E_COMP [2:0]
DRC_THRESH_
COMP [5:0]
DRC_AMP_CO
MP [4:0]
LABEL
DEFAULT
000000
00000
100
000
Compressor slope R0
000 = 1 (no compression)
001 = 1/2
010 = 1/4
011 = 1/8
100 = 1/16
101 = 0
110 = Reserved
111 = Reserved
Compressor slope R1
000 = 1 (no compression)
001 = 1/2
010 = 1/4
011 = 1/8
100 = 0
101 = Reserved
11X = Reserved
Compressor threshold T (dB)
000000 = 0dB
000001 = -0.75dB
000010 = -1.5dB
… (-0.75dB steps)
111100 = -45dB
111101 = Reserved
11111X = Reserved
Compressor amplitude at threshold
YT (dB)
00000 = 0dB
00001 = -0.75dB
00010 = -1.5dB
… (-0.75dB steps)
11110 = -22.5dB
11111 = Reserved
PP, Rev 3.1, August 2009
DESCRIPTION
Pre-Production
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