ak4650 AKM Semiconductor, Inc., ak4650 Datasheet - Page 31

• Manufacturer Part Number: ak4650
• Description: 16bit 6 Codec With Mic/hp/spk-amp & Tsc
• Manufacturer: AKM Semiconductor, Inc.

Register
Name
LMTH
LTM1-0
ZELMN
ZTM1-0
WTM1-0
REF5-0
IPGA5-0
LMAT1-0
RGAIN
ALC1
(3) Example of ALC1 Operation
Table 22 shows the examples of the ALC1 setting. In case of this examples, 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”.
IPGA gain at ALC1 operation start can be changed from the default value of IPGA5-0 bits while PMMIC bit is “1” and
ALC1 bit is “0”. When ALC1 bit is changed from “1” to “0”, IPGA holds the last gain value set by ALC1 operation.
MS0502-E-01
WR (ALC1= “1”, LMAT1-0, RGAIN, LMTH, ZELMN)
LTM1-0, LMTH, LMAT1-0, WTM1-0, ZTM1-0, RGAIN, REF5-0, ZELMN bits
WR (ZTM1-0, WTM1-0, LTM1-0)
Comment
Limiter detection Level
Limiter operation period at ZELMN
bit = “1”
Limiter zero crossing detection
Zero crossing timeout period
Recovery waiting period
*WTM1-0 bits should be the same
Maximum gain at recovery operation
Gain of IPGA at ALC1 operation start
Limiter ATT Step
Recovery GAIN Step
ALC1 Enable bit
data as ZTM1-0 bits
ALC1 Operation
WR (IPGA5-0)
Manual Mode
WR (REF5-0)
Note : WR : Write
Figure 19. Registers set-up sequence at ALC1 operation
* The value of IPGA should be
Table 22. Example of the ALC1 setting
the same or smaller than REF’s
Data
3DH
37H
00
00
00
00
1
0
0
1
- 31 -
fs=8kHz
Operation
Don’t use
+26.5dB
Enable
Enable
0.5dB
0.5dB
4dBFS
16ms
16ms
0dB
Example:
3DH
Data
Limiter = Zero crossing Enable
Recovery Cycle = 16ms @ fs= 8kHz
Limiter and Recovery Step = 0.5dB
Maximum Gain = +26.5dB
Limiter Detection Level = 4dBFS
ALC bit = “1”
37H
00
01
01
00
1
0
0
1
(1) Addr=66H, Data=4100H
(2) Addr=64H, Data=3D31H
(3) Addr=0EH, Data=0077H
(4) Addr=66H, Data=6100H
fs=16kHz
Operation
Don’t use
+26.5dB
Enable
Enable
0.5dB
0.5dB
4dBFS
16ms
16ms
0dB
Data
3DH
37H
00
10
10
00
1
0
0
1
fs=44.1kHz
[AK4650]
Operation
Don’t use
+26.5dB
11.6ms
11.6ms
Enable
Enable
2007/04
0.5dB
0.5dB
4dBFS
0dB