AK4538 Datasheet, PDF (29/70 Pages) Asahi Kasei Microsystems – 16Bit DS CODEC with MIC/HP/SPK-AMP

ASAHI KASEI
[AK4538]
n De-emphasis Filter
The AK4538 includes the digital de-emphasis filter (tc = 50/15µs) by IIR filter. Setting the DEM1-0 bits enables the
de-emphasis filter.
DEM1
0
0
1
1
DEM0
Mode
0
44.1kHz
1
OFF
0
48kHz
1
32kHz
Table 19. De-emphasis Control
Default
n Bass Boost Function
The BST1-0 bits control the amount of low frequency boost applied to the DAC output signal. If the BST1-0 bits are set to
“10” (MID Level), use a 47µF capacitor for AC-coupling. If the boosted signal exceeds full scale, the analog output clips
to the full scale. Figure 22 shows the boost frequency response at –20dB signal input.
Boost Frequency (fs=44.1kHz)
0
-5
MAX
-10
MID
-15
-20
MIN
-25
0.01
0.1
1
10
Frequency [kHz]
Figure 22. Boost Frequency (fs=44.1kHz)
BST1
BST0
Mode
0
0
OFF
Default
0
1
MIN
1
0
MID
1
1
MAX
Table 20. Low Frequency Boost Control
MS0198-E-01
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