AK4632VN AKM [Asahi Kasei Microsystems], AK4632VN Datasheet - Page 33

• Manufacturer Part Number: AK4632VN
• Description: 16-Bit ?? Mono CODEC with ALC & MIC/SPK/Video-AMP
• Manufacturer: AKM [Asahi Kasei Microsystems]

ASAHI KASEI
[3] Example of ALC1 Operation
Table 15 shows the example of the ALC1 setting. In case of this example, ALC1 operation starts from 0dB.
The following registers should not be changed during the ALC1 operation. These bits should be changed, after the ALC1
operation is finished by ALC1 bit = “0” or PMMIC bit = “0”.
When setting IPGA gain at the start of ALC1 operation, IPGA6-0 bits should be set while PMMIC bit is “1” and ALC1 bit
is “0”. When PMMIC bit = “1”, IPGA6-0 bits value aren’t reflected to IPGA. When ALC1 bit is changed from “1” to “0”,
IPGA holds the last gain value set automatically by ALC1 operation.
MS0396-E-00
Register Name Comment
LMTH
LTM1-0
ZELM
ZTM1-0
WTM1-0
REF6-0
IPGA6-0
LMAT1-0
RATT
ALC1
• LTM1-0, LMTH, LMAT1-0, WTM1-0, ZTM1-0, RATT, REF6-0, ZELM bits
WR (ALC1= “1”, LMAT1-0, RATT, LMTH, ZELM)
WR (ZTM1-0, WTM1-0, LTM1-0)
Limiter detection Level
Limiter operation period at ZELM = 1
Limiter zero crossing detection
Zero crossing timeout period
Recovery waiting period
*WTM1-0 bits should be the same data
Maximum gain at recovery operation
IPGA gain at the start of ALC1 operation
Limiter ATT Step
Recovery GAIN Step
ALC1 Enable bit
as ZTM1-0 bits
ALC1 Operation
Note : WR : Write
WR (IPGA6-0)
WR (REF6-0)
Manual Mode
Figure 31. Registers set-up sequence at the ALC1 operation
Table 15. Examples of the ALC1 Setting
* The value of IPGA should be
the same or smaller than REF’s
- 33 -
Data
47H
10H
00
00
00
00
1
0
0
1
fs=8kHz
Operation
Don’t use
+27.5dB
Example:
-4dBFS
Enable
Enable
1 step
1 step
16ms
16ms
0dB
Limiter = Zero crossing Enable
Recovery Cycle = 16ms @ fs= 8kHz
Limiter and Recovery Step = 1
Maximum Gain = +27.5dB
Limiter Detection Level = -4dBFS
ALC2 bit = “1” (default)
(1) Addr=06H, Data=00H
(2) Addr=08H, Data=47H
(3) Addr=09H, Data=10H
(4) Addr=07H, Data=61H
Data
47H
10H
00
01
01
00
1
0
0
1
fs=16kHz
Operation
Don’t use
+27.5dB
-4dBFS
Enable
Enable
1 step
1 step
16ms
16ms
0dB
[AK4632]
2005/06