[AK4675]
■ Digital Volume Control for B/T MIC Input (BIVOL)
The AK4675 has a digital volume control (5 levels, 6dB step) for B/T mic input. The volume can be set by the BIV2-0
bits. The volume is included at SDTIB input. The input data is changed from 0 to –24dB.
BIV2-0
0H
Gain
0dB
(default)
1H
2H
3H
4H
−6dB
−12dB
−18dB
−24dB
N/A
Others
Table 41. B/T Mic Volume Code Table (N/A: Not available)
■ Path & Mixing Setting of Digital Block (Figure 56.)
PMADL and PMADR bits set both ADC power management and output data selection. In case of mono operation, the
same data is output to both channel slots.
PMADL
PMADR
ADC Lch data
All “0”
Rch Input Signal
Lch Input Signal
Lch Input Signal
ADC Rch data
All “0”
Rch Input Signal
Lch Input Signal
Rch Input Signal
0
0
1
1
0
1
0
1
(default)
Table 42. ADC Mono/Stereo Select
PFSEL bit select the input data of programmable filter.
PFSEL
Programmable Filter Input
0
1
ADC Output (selected by Table 42.) (default)
SDTI Input (selected by Table 48)
Table 43. Programmable Filter Input Signal Select
When ADM bit is “1”, ALC output data is output to both channels of SDTO and SVOLA as (L+R)/2, respectively.
ADM
0
1
Lch
L
(L+R)/2
Rch
R
(L+R)/2
(default)
Table 44. ALC Output Mono Mixing
MS0963-E-00
2008/05
- 86 -
AKM [ ASAHI KASEI MICROSYSTEMS ]
