AK4112B Datasheet, PDF (12/30 Pages) Asahi Kasei Microsystems – HIGH FEATURE 96kHz 24BIT DIR

ASAHI KASEI
[AK4112B]
„ De-emphasis Filter Control
The AK4112B includes the digital de-emphasis filter (tc=50/15µs) by IIR filter corresponding to four sampling
frequencies (32kHz, 44.1kHz, 48kHz and 96kHz). When DEAU bit=“1”, the de-emphasis filter is enabled automatically
by sampling frequency and pre-emphasis information in the channel status. The AK4112B goes this mode at default.
Therefore, in Parallel Mode, the AK4112B is always placed in this mode and the de-emphasis filter is controlled by the
status bits in channel 1. In Serial Mode, DEM0/1 and DFS bits can control the de-emphasis filter when DEAU is “0”.
When the “0” data is input to the de-emphasis filter, the output data will be “0” or “-1”. The internal de-empahsis filter is
bypassed and the recovered data is output without any change if either pre-emphasis or de-emphasis Mode is OFF.
FS96 FS1
0
0
0
0
0
1
0
1
1
0
1
0
1
1
1
1
FS0 Mode
0
44.1kHz
1
OFF
0
48kHz
1
32kHz
0
OFF
1
OFF
0
96kHz
1
OFF
Table 7. De-emphasis Auto Control at DEAU=“1” and PEM=“1”
DFS DEM1 DEM0 Mode
0
0
0 44.1kHz
0
0
1
OFF Default
0
1
0
48kHz
0
1
1
32kHz
1
0
0
OFF
1
0
1
OFF
1
1
0
96kHz
1
1
1
OFF
Table 8. De-emphasis Manual Control at DEAU=“0” and PEM=“1”
MS0078-E-02
- 12 -
2004/04