AK4642EN Datasheet, PDF (31/83 Pages) Asahi Kasei Microsystems – Stereo CODEC with MIC/HP/SPK-AMP

ASAHI KASEI
[AK4642EN]
„ Digital High Pass Filter
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.
„ MIC/LINE Input Selector
The AK4642 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 21).
MDIF1 bit
0
1
MDIF2 bit
0
1
0
1
INL bit
INR bit
Lch
0
0
LIN1
1
LIN1
1
0
LIN2
1
LIN2
0
x
LIN1
1
x
N/A
x
0
N/A
1
IN1+/−
x
x
IN1+/−
Table 15. MIC/Line In Path Select
Rch
RIN1
RIN2
RIN1
RIN2
IN2+/−
N/A
N/A
RIN2
IN2+/−
Default
AK4642
LIN1/IN1− pin
RIN1/IN1+ pin
INL bit
MDIF1 bit
ADC Lch
RIN2/IN2− pin
LIN2/IN2+ pin
INR bit
MDIF2 bit
Figure 20. Mic/Line Input Selector
ADC Rch
MS0420-E-00
- 31 -
2005/09