
[AK4671] 
MS0666-E-00 
2007/10 
- 62 - 
1.
ADC: Include the Digital Filter (LPF) for ADC as shown in “
FILTER CHRACTERISTICS
”. 
2.
DAC: Include the Digital Filter (LPF) for DAC as shown in “
FILTER CHRACTERISTICS
”. 
3.
HPF: High Pass Filter. Applicable to use as Wind-Noise Reduction Filter. (See “
Digital Programmable Filter
”.) 
4.
LPF: Low Pass Filter (See “
Digital Programmable Filter
”.) 
5.
Stereo Separation: Stereo Separation Emphasis Filter & Gain Compensation. (See “
Digital Programmable Filter
”.) 
Gain Compensation is composed with EQ0 and Gain blocks. This block adjusts the frequency response after Stereo 
Separation Emphasis. 
6.
5-Band Notch: Applicable to use as Equalizer or Notch Filter. (See “
Digital Programmable Filter
”.) 
7.
ALC: Input Digital Volume with ALC function. (See “
Input Digital Volume
” and “
ALC Operation
”.) 
8.
SVOLA: Side Tone Volume at Internal MIC/SPK or External Headset Phone Call. (See “
Side Tone Volume
”.) 
9.
5-Band EQ: Equalizer for playback path. (See “
5-band Equalizer
”.) 
10.
DATT: Digital Volume for playback path. (See “
Digital Output Volume
”.) 
11.
SMUTE: Soft mute. (See “
Soft Mute
”.) 
12.
DATT-B: Digital Volume for Recording of Received Voice. (See “
Digital Volume for Recording of Received 
Voice
”) 
13.
DATT-C: Digital Volume of Received Voice. (See “
Digital Volume for Received Voice
”) 
14.
SVOLA: Side Tone Volume at B/T Headset Phone Call. (See “
Side Tone Volume for B/T Phone Call
”.) 
Mode 
PMADL 
PMADR 
PMDAL 
Recording Mode 
1 
1 
1 
0 
0 
1 
Recording & 
1 
1 
Playback Mode 
1 
0 
0 
1 
Playback Mode 
0 
0 
Table 22. Recode/Playback Mode 
PMDAR 
0 
0 
0 
1 
1 
1 
1 
PFSEL 
0 
0 
0 
0 
0 
0 
1 
Figure 
Figure 58 
Figure 59 
Figure 60 
0 
0 
0 
1 
1 
1 
1 
2nd Order 
HPF 
ADC 
5 Band 
Notch 
ALC 
(Volume) 
1st Order
LPF 
Stereo 
Separation
Gain 
Compensation
Figure 58. Path at Recording Mode 
DAC 
2nd Order 
HPF 
ADC 
5 Band 
Notch 
ALC 
(Volume) 
SMUTE 
DEM 
1st Order
LPF 
Stereo 
Separation
Gain 
Compensation
DATT
5 Band 
EQ 
Figure 59. Path at Recording & Playback Mode 
DAC 
1st Order 
HPF 
ADC 
5 Band 
EQ 
ALC 
(Volume) 
1st Order
LPF 
Stereo 
Separation
Gain 
Compensation
1st Order
HPF 
“0” Data
SMUTE
DEM 
DATT 
5 Band 
EQ 
Figure 60. Path at Playback Mode