[AK4679]
■ Input Digital Volume (Manual Mode)
The input digital volume becomes a manual mode when ALC bit is “0”. This mode is used in the case shown below.
1. After exiting reset state, set-up the registers for the ALC operation (ZTM1-0, LMTH1-0 bits and etc)
2. When the registers for the ALC operation (Limiter period, Recovery period and etc) are changed.
For example, in case of changing the sampling frequency.
3. When IVOL is used as a manual volume.
IVL7-0 and IVR7-0 bits set the gain of the volume control (Table 37). When IVOLC bit is “0”, IVL7-0 and IVR7-0 bits
control Lch and Rch volume values independently. When IVOLC bit is “1”, IVL7-0 bits controls both channels. The
IVOL value is changed at zero crossing or timeout. Zero crossing timeout period is set by ZTM1-0 bits. If IVL7-0 or
IVR7-0 bits are written during PMADL=PMADR=PMDML=PMDMR bits = “0”, IVOL operation starts with the written
values at the end of the ADC initialization cycle after PMADL, PMADR, PMDML or PMMDR bit is changed to “1”.
IVL7-0 bits
IVR7-0 bits
GAIN (dB)
Step
F1H
F0H
EFH
:
+36.0
+35.625
+35.25
:
92H
91H
90H
:
+0.375
0.0
−0.375
:
0.375dB
(default)
03H
02H
01H
00H
−53.25
−53.625
−54
MUTE
Table 37. Input Digital Volume Setting
MS1402-E-06
2013/02
- 78 -
AKM [ ASAHI KASEI MICROSYSTEMS ]
