ak4647 AKM Semiconductor, Inc., ak4647 Datasheet - Page 27

• Manufacturer Part Number: ak4647
• Description: Stereo Codec With Mic/hp-amp
• Manufacturer: AKM Semiconductor, Inc.

ASAHI KASEI
The ADC has a digital high pass filter for DC offset cancellation. The cut-off frequency of the HPF is 0.9Hz
(@fs=44.1kHz) and scales with sampling rate (fs). When PMADL bit = “1” or PMADR bit = “1”, the HPF of ADC is
enabled but the HPF of DAC is disabled. When PMADL=PMADR bits = “0”, PMDAC bit = “1”, the HPF of DAC is
enabled but the HPF of ADC is disabled.
The AK4647 has input selector. When MDIF1 and MDIF2 bits are “0”, INL and INR bits select LIN1/LIN2 and
RIN1/RIN2, respectively. When MDIF1 and MDIF2 bits are “1”, LIN1, RIN1, LIN2 and RIN2 pins become IN1−, IN1+,
IN2+ and IN2− pins respectively. In this case, full-differential input is available (Figure 22). When full-differential input
is used, the signal should not be input to the pins marked by “X” in.
MS0566-E-00
Digital High Pass Filter
MIC/LINE Input Selector
MDIF1 bit
Others
0
0
0
0
0
1
1
Table 16. Handling of MIC/Line Input Pins (“-“: N/A; “X”: Signal should not be input.)
MDIF2 bit
MDIF1 bit
0
0
0
0
1
0
1
Register
0
0
1
1
MDIF2 bit
INL bit
Table 15. MIC/Line In Path Select
0
0
1
0
0
0
0
0
1
0
1
LIN1
IN1−
Pin
- 27 -
O
O
O
O
INR bit
0
1
0
1
0
1
0
RIN1
IN1+
O
X
O
O
LIN2
IN2+
IN1+/−
IN1+/−
LIN1
LIN1
LIN2
LIN2
LIN1
O
O
X
O
N/A
Lch
RIN2
IN2−
O
O
O
O
IN2+/−
IN2+/−
RIN1
RIN2
RIN1
RIN2
RIN2
N/A
Rch
Default
[AK4647]
2006/11