AK4691 Datasheet, PDF (36/80 Pages) Asahi Kasei Microsystems – 4ch ADC + 2ch DAC with MIC/HP/SPK-AMP

[AK4691]
FIL3A, EQA, FIL1A, GN1A, and GN0A bits are for ADC1.
FIL3B, EQB, FIL1B, GN1B, and GN0B bits are for ADC2.
FIL3A(FIL3B) coefficient also sets the attenuation of the stereo separation emphasis.
The combination of GN1-0A(GN1-0B) bits (Table 24) and EQA(EQB) coefficient set the compensation gain.
FIL1A(FIL1B) and FIL3A(FIL3B) blocks become HPF when F1ASA(F1ASB) and F3ASA(F3ASB) bits are “0” and
become LPF when F1ASA(F1ASB) and F3ASA(F3ASB) bits are “1”, respectively.
When EQA(EQB) and FIL1A(FIL1B) bits are “0”, EQA(EQB) and FIL1A(FIL1B) blocks become “through” (0dB).
When FIL3A(FIL3B) bit is “0”, FIL3A(FIL3B) block become “MUTE”. When each filter coefficient is changed, each
filter should be set to “through” (“MUTE” in case of FIL3A (FIL3B)).
Wind-noise reduction
Stereo separation emphasis
Gain compensation
FIL1A
FIL3A
EQA
Gain
ADC1
Any coefficient
F1A13A-0A
F1B13A-0A
F1ASA
Any coefficient
F3A13A-0A
F3B13A-0A
F3ASA
0dB ∼ -10dB
MUTE
(set by
FIL3A coefficient)
Wind-noise reduction
FIL1B
Stereo separation emphasis
FIL3B
Any coefficient
EQA15A-0A
EQB13A-0A
EQC15A-0A
+12dB ∼ 0dB
GN1A-0A
+24/+12/0dB
Gain compensation
EQB
Gain
ALC
ADC2
Any coefficient
F1A13B-0B
F1B13B-0B
F1ASB
Any coefficient 0dB ∼ -10dB
F3A13B-0B MUTE
F3B13B-0B (set by
F3ASB
FIL3B coefficient)
Any coefficient
EQA15B-0B
EQB13B-0B
EQC15B-0B
+12dB ∼ 0dB
GN1B-0B
+24/+12/0dB
Figure 25. Digital EQ/HPF/LPF
GN1A bit
GN1B bit
GN0A bit
GN0B bit
Gain
0
0
0dB
(default)
0
1
+12dB
1
x
+24dB
Table 24. Gain select of gain block (x: Don’t care)
MS0672-E-00
- 36 -
2007/11