AK4490EN Datasheet, PDF (33/68 Pages) Asahi Kasei Microsystems – Premium 32-Bit 2ch DAC

[AK4490EN]
Full Scale (FS) DSD Signal Detection Function
The AK4490EN has a full scale (FS) detection function at each channel in DSD Mode. When DSDL or
DSDR input data is continuously “0” (-FS) or “1” (+FS) for 2048 cycles, the AK4490EN detects full scale
and enters full scale detection status and DML or DMR bit becomes “1”. The output will be muted by full
scale detection if DDM bit = “1”. When DSDD bit is “0”, the output is attenuated in soft transition. When
DSDD bit is “1”, the soft transition is disabled.
Recovery method to normal operation mode from full scale detection status is controlled by DMC bit when
DDM bit = “1”. When DMC bit = “0”, the AK4490EN returns to normal operation automatically by a normal
signal input. When DMC bit = “1”, the AK4490EN returns normal operation by writing DMRE bit = “1”.
Table 18. DSD Mode and the Device Status after Detection (DDM bit= “1”)
DSDD
Mode
Status After Detection
0
Normal Path
Soft Mute Enable
(default)
1
Volume Bypass
Soft Mute Disable
Table 19. Recovery Method to Normal Operation Mode from Full Scale Detection Status
DDM
DMC
DMRE
Status After Detection
0
*
*
When full scale is detected, Mute function is Disable. (default)
When full scale is detected, Mute function is Enable.
1
0
*
The AK4490EN returns normal operation automatically
by a normal signal input.
When full scale is detected, Mute function is Enable.
1
1
0
The AK4490EN keeps mute mode, even if a normal
signal is input.
1
1
1
(Note 28)
When full scale is detected, Mute function is Enable.
The AK4490EN returns normal operation, when a
normal signal is input and DMRE bit is set “1”.
Note 28. After the AK4490EN returns normal operation, DMRE bit is returned to “0” automatically.
DSD Error
(DDR or DDLbit)
2048fs
DSD Data
DSD Data
DSD Data(FS or -FS )
DSD Data
AOUT
Mode _{Figure 9. Analog Output Waveform on DSD FS Detection (DSDD bit= “1”)}
DSD Error
(DDR or DDLbit)
2048fs
DSD Data
DSD Data
DSD Data(FS or -FS )
DSD Data
AOUT
Mode
Figure 10. Analog Output Waveform on DSD FS Detection (DSDD bit= “0”)
015013666-E-01
- 33 -
2015/12