ak4538 AKM Semiconductor, Inc., ak4538 Datasheet - Page 29

• Manufacturer Part Number: ak4538
• Description: 16bit ?? Codec With Mic/hp/spk-amp
• Manufacturer: AKM Semiconductor, Inc.

ASAHI KASEI
n De-emphasis Filter
The AK4538 includes the digital de-emphasis filter (tc = 50/15 s) by IIR filter. Setting the DEM1-0 bits enables the
de-emphasis filter.
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 47 F 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.
MS0198-E-01
-10
-15
-20
-25
-5
0
0.01
DEM1
BST1
0
0
1
1
0
0
1
1
Figure 22. Boost Frequency (fs=44.1kHz)
Table 20. Low Frequency Boost Control
MIN
Table 19. De-emphasis Control
Boost Frequency (fs=44.1kHz)
DEM0
0
1
0
1
BST0
0
1
0
1
0.1
Frequency [kHz]
- 29 -
MAX
44.1kHz
48kHz
32kHz
Mode
OFF
Mode
MAX
MIN
MID
OFF
MID
1
Default
Default
10
[AK4538]
2003/5