ak4665a AKM Semiconductor, Inc., ak4665a Datasheet - Page 30

• Manufacturer Part Number: ak4665a
• Description: 20-bit Stereo Codec With Mic/hp-amp
• Manufacturer: AKM Semiconductor, Inc.

ASAHI KASEI
(3) Example for ALC2 Operation
Table 29 shows the examples of the ALC2 setting. The ALC2 operation starts from 0dB.
The following registers should not be changed during the ALC2 operation. These bits should be changed after the ALC2
operation is finished by ALC2 bit is “0” or PMLO bit is “0”.
MS0440-E-01
Register Name Comment
LMTHP
LTMP1-0
WTMP1-0
REFP7-0
LMATP1-0
RGAINP
PTS1-0
ALC2
- LMTHP, LTMP1-0, LMATP1-0, WTMP1-0, RGAINP, REFP5-0, PTS1-0
WR (LMATP1-0, RGAINP, WT MP1-0)
WR (LMTHP, LTMP1-0)
Limiter detection Level
Maximum gain at recovery operation
Recovery waiting period
Maximum gain at recovery operation
Limiter ATT Step
Recovery GAIN Step
ALC2 recovery transition time
ALC2 Enable bit
WR (ALC2= “1”)
ALC2 Operation
WR (REFP5-0)
WR (PTS1-0)
Note : WR : Write
ALC2=OFF
Figure 18. Registers set-up sequence at ALC2 operation
Table 29. Example for the ALC2 setting
Example:
- 30 -
Limiter Cycle = 544 µ s @ fs=44.1kHz
Recovery Cycle = 557ms @ fs= 44.1kHz
Limiter and Recovery Step = 1
Maximum Gain = +12dB
Limiter Detection Level = − 11.5dBV
Recovery Transition Time = 139ms @ fs=44.1kHz
ALC2 bit = “1”
Data
30H
10
11
00
11
1
0
1
−11.5dBV
Enable
16kHz
32kHz
512ms
+12dB
128ms
500µs
0.5dB
0.5dB
8kHz
(4) Addr =14H, Data=C0H
(1) Addr=12H, Data=18H
(2) Addr=13H, Data=18H
(3) Addr=11H, Data=30H
(5) Addr=12H, Data=38H
11.025kHz
−11.5dBV
22.05kHz
44.1kHz
+12dB
139ms
Enable
557ms
544µs
0.5dB
0.5dB
fs
−11.5dBV
Enable
12kHz
24kHz
48kHz
512ms
+12dB
128ms
500µs
0.5dB
0.5dB
[AK4665A]
2006/05