AK4647VN AKM [Asahi Kasei Microsystems], AK4647VN Datasheet - Page 38

• Manufacturer Part Number: AK4647VN
• Description: Stereo CODEC with MIC/HP-AMP
• Manufacturer: AKM [Asahi Kasei Microsystems]

ASAHI KASEI
The AK4647 includes the digital de-emphasis filter (tc = 50/15μs) by IIR filter. Setting the DEM1-0 bits enables the
de-emphasis filter (Table 31).
The BST1-0 bits control the amount of low frequency boost applied to the DAC output signal (Table 32). If the BST1-0
bits are set to “01” (MIN Level), use a 47μF capacitor for AC-coupling. If the boosted signal exceeds full scale, the analog
output clips to the full scale. Figure 27 shows the boost frequency response at –20dB signal input.
MS0566-E-00
De-emphasis Filter
Bass Boost Function
-10
-15
-20
-25
-5
0
10
MID
MIN
MAX
Figure 27. Bass Boost Frequency Response (fs=44.1kHz)
DEM1
BST1
0
0
1
1
0
0
1
1
Table 31. De-emphasis Control
Table 32. Bass Boost Control
Boost Filter (fs=44.1kHz)
100
DEM0
0
1
0
1
BST0
0
1
0
1
Frequency [Hz]
- 38 -
44.1kHz
48kHz
32kHz
Mode
OFF
Mode
MAX
MIN
MID
OFF
1000
Default
Default
10000
[AK4647]
2006/11