AK4650 Datasheet, PDF (32/86 Pages) Asahi Kasei Microsystems – 16Bit ΔΣ CODEC with MIC/HP/SPK-AMP & TSC

[AK4650]
■ De-emphasis Filter
The AK4650 includes the digital de-emphasis filter (tc = 50/15μs) by IIR filter. Setting the DEM1-0 bits enables the
de-emphasis filter (Table 23).
DEM1
0
0
1
1
DEM0
Mode
0
44.1kHz
1
OFF
0
48kHz
1
32kHz
Table 23. De-emphasis Control
(default)
■ Bass Boost Function
The BST1-0 bits control the amount of low frequency boost applied to the DAC output signal (Table 24). If the BST1-0
bits are set to “10” (MID Level), AC-coupling capacitor can be sized down to 47μF. If the boosted signal exceeds the full
scale, the analog output clips to the full scale. Figure 20 shows the boost frequency response at –20dB signal input.
Boost Filter (fs=48kHz)
20
MAX
15
MID
10
MIN
5
0
-5
10
100
1000
Frequency [Hz]
Figure 20. Bass Boost Frequency (fs=48kHz)
BST1
0
0
1
1
BST0
Mode
0
OFF
1
MIN
0
MID
1
MAX
Table 24. Bass Boost Control
(default)
10000
MS0502-E-01
- 32 -
2007/04