[AK4646]
■ Input Digital Volume (Manual Mode)
The input digital volume becomes a manual mode at ALC1 bit = “0” when either Lch and Rch of ADC is powered-up
(PMADL bit = “1” or PMADR bit = “1”) and DAFIL 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, LMTH and etc)
2. When the registers for the ALC operation (Limiter period, Recovery period and etc) are changed.
For example; when the change of 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 34). The IVOL value is changed at zero crossing or
timeout. The zero crossing timeout period is set by ZTM1-0 bits. If IVL7-0 or IVR7-0 bits are written during
PMADL=PMADR bits = “0”, IVOL operation starts with the written values at the end of the ADC initialization cycle
after PMADL or PMADR bit is changed to “1”.
If IVL7-0 or IVR7-0 bits are written during PMADL=PMADR bits = “0”, IVOL operation starts with the written values
at the end of the ADC initialization cycle after PMADL or PMADR bit is changed to “1”.
IVL7-0
IVR7-0
GAIN (dB)
Step
F1H
F0H
EFH
:
+36.0
+35.625
+35.25
:
E2H
E1H
E0H
:
+30.375
+30.0
+29.625
:
0.375dB
(default)
03H
02H
01H
00H
−53.25
−53.625
−54
MUTE
Table 34. Input Digital Volume Setting
MS0557-E-05
2011/01
- 43 -
AKM [ ASAHI KASEI MICROSYSTEMS ]
