AK4387 Datasheet, PDF (11/21 Pages) Asahi Kasei Microsystems – 106dB 192kHz 24-Bit 2ch ΔΣ DAC

ASAHI KASEI
[AK4387]
LRCK
BICK
(64fs)
SDTI
0123
23 24 25
31 0 1 2 3
23 24 25
31 0 1
23 22
1 0 Don’t care
23 22
1 0 Don’t care
23
23:MSB, 0:LSB
Lch Data
Rch Data
Figure 4. Mode 3 Timing
„ De-emphasis Filter
A digital de-emphasis filter is available for 32, 44.1 or 48kHz sampling rates (tc = 50/15µs) and is enabled or disabled
with DEM0 and DEM1. In case of double speed and quad speed mode, the digital de-emphasis filter is always off.
DEM1
0
0
1
1
DEM0
0
1
0
1
Mode
44.1kHz
OFF
48kHz
32kHz
Default
Table 8. De-emphasis Filter Control (Normal Speed Mode)
„ Output Volume
The AK4387 includes channel independent digital output volumes (ATT) with 256 levels at linear step including MUTE.
These volumes are in front of the DAC and can attenuate the input data from 0dB to –48dB and mute. When changing
levels, transitions are executed via soft changes; thus no switching noise occurs during these transitions. The transition
time of 1 level and all 256 levels is shown in Table 10.
Sampling Speed
Normal Speed Mode
Double Speed Mode
Quad Speed Mode
Transition Time
1 Level
255 to 0
4LRCK
1020LRCK
8LRCK
2040LRCK
16LRCK
4080LRCK
Table 9. ATT Transition Time
MS0429-E-00
- 11 -
2005/09