AK4691EG AKM [Asahi Kasei Microsystems], AK4691EG Datasheet - Page 36

• Manufacturer Part Number: AK4691EG
• Description: 4ch ADC + 2ch DAC with MIC/HP/SPK-AMP
• Manufacturer: AKM [Asahi Kasei Microsystems]

Wind-noise reduction
Wind-noise reduction
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
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)).
MS0672-E-00
Any coefficient
Any coefficient
F1A13A-0A
F1B13A-0A
F1A13B-0B
F1B13B-0B
F1ASB
F1ASA
FIL1A
FIL1B
Any coefficient
Any coefficient
F3A13A-0A
F3B13A-0A
F3A13B-0B
F3B13B-0B
F3ASA
F3ASB
Stereo separation emphasis
Stereo separation emphasis
GN1A bit
GN1B bit
FIL3B
FIL3A
Table 24. Gain select of gain block (x: Don’t care)
0
0
1
0dB ∼ -10dB
MUTE
(set by
0dB ∼ -10dB
MUTE
(set by
FIL3B coefficient)
FIL3A coefficient)
Figure 25. Digital EQ/HPF/LPF
(Table
GN0A bit
GN0B bit
24) and EQA(EQB) coefficient set the compensation gain.
0
1
x
- 36 -
Any coefficient
Any coefficient
+12dB ∼ 0dB
+12dB ∼ 0dB
EQA15A-0A
EQB13A-0A
EQC15A-0A
EQA15B-0B
EQB13B-0B
EQC15B-0B
Gain compensation
Gain compensation
EQA
EQB
+12dB
+24dB
Gain
0dB
+24/+12/0dB
+24/+12/0dB
GN1B-0B
GN1A-0A
Gain
Gain
(default)
ALC
ADC1
ADC2
[AK4691]
2007/11