[AK4627]
■ De-emphasis Filter
The AK4627 includes the digital de-emphasis filter (tc=50/15µs) by IIR filter. De-emphasis filter is not available in
Double Speed Mode and Quad Speed Mode. This filter corresponds to three sampling frequencies (32kHz, 44.1kHz,
48kHz). De-emphasis of each DAC can be set individually by register data of DEMA1-C0 (DAC1: DEMA1-0, DAC2:
DEMB1-0, DAC3: DEMC1-0, see “Register Definitions”).
Mode
Sampling Speed
Normal Speed
Normal Speed
Normal Speed
Normal Speed
DEM1
DEM0
DEM
44.1kHz
OFF
48kHz
32kHz
0
1
2
3
0
0
1
1
0
1
0
1
(default)
Table 7. De-emphasis control
■ Digital High Pass Filter
The ADC has a digital high pass filter for DC offset cancellation. The cut-off frequency of the HPF is 1.0Hz at fs=48kHz
and scales with sampling rate (fs).
MS1278-E-02
2012/03
- 17 -
AKM [ ASAHI KASEI MICROSYSTEMS ]
