WM8985_07 WOLFSON [Wolfson Microelectronics plc], WM8985_07 Datasheet - Page 49

• Manufacturer Part Number: WM8985_07
• Description: Multimedia CODEC With Class D Headphone and Line Out
• Manufacturer: WOLFSON [Wolfson Microelectronics plc]

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Table 25 ALC Min Gain Values
ALC HOLD TIME (NORMAL MODE ONLY)
Table 26 ALC Hold Time
Note that if the ALC gain setting strays outside the ALC operating range, either by starting the ALC
outside of the range or changing the ALCMAX or ALCMIN settings during operation, the ALC will
immediately adjust the gain to return to the ALC operating range. It is recommended that the ALC
starting gain is set between the ALCMAX and ALCMIN limits.
In Normal mode, the ALC has an adjustable hold time which sets a time delay before the ALC
begins it’s decay phase (gain increasing). The hold time is set by the ALCHLD register.
If the hold time is exceeded this indicates that the signal has reached a new average level and the
ALC will increase the gain to adjust for that new average level.
threshold during the hold period, the hold phase is abandoned and the ALC returns to normal
operation.
ALCMIN
000
001
010
011
100
101
110
111
R33
ALC Control
2
REGISTER
ADDRESS
7:4
BIT
Minimum Gain (dB)
ALCHLD
-12
12
18
24
30
LABEL
-6
0
6
0000
DEFAULT
ALC hold time before gain is increased.
DESCRIPTION
If the signal goes above the
PP, Rev 3.5, January 2007
WM8985
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