AK4425A AKM [Asahi Kasei Microsystems], AK4425A Datasheet - Page 16

• Manufacturer Part Number: AK4425A
• Description: 192kHz 24-Bit Stereo ?? DAC with 2Vrms Output
• Manufacturer: AKM [Asahi Kasei Microsystems]

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The AK4425A 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
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Soft mute operation is performed in digital domain. When the SMUTE bit is set to “1”, the output signal is attenuated by
-∞ during ATT_DATA×ATT transition time
“0”, the mute is cancelled and the output attenuation gradually changes to the ATT level during ATT_DATA×ATT
transition time. If the soft mute is cancelled before attenuating to -∞, the attenuation is discontinued and returned to ATT
level by the same cycle. The soft mute is effective for changing the signal source without stopping the signal transmission.
Notes:
MS1127-E-01
Output Volume
Soft Mute Operation
(2) The analog output corresponding to the digital input has group delay, GD.
(1) ATT_DATA×ATT transition time
(3) If the soft mute is cancelled before attenuating to -∞ after starting the operation, the attenuation is discontinued and
SMUTE bit
Attenuation
AOUT
(1020/fs) at ATT_DATA=255.
returned to ATT level by the same cycle.
ATT Level
-∞
Sampling Speed
Normal Speed Mode
Double Speed Mode
Quad Speed Mode
(1)
(Table
Table 8. ATT Transition Time
Figure 11. Soft Mute function
(Table
8). For example, in Normal Speed Mode, this time is 1020LRCK cycles
8) from the current ATT level. When the SMUTE bit is returned to
Table
16LRCK
4LRCK
8LRCK
GD
1 Level
- 16 -
(2)
8.
Transition Time
(1)
1020LRCK
2040LRCK
4080LRCK
255 to 0
GD
(3)
[AK4425A]
2011/03