AK4480 AKM [Asahi Kasei Microsystems], AK4480 Datasheet - Page 28

• Manufacturer Part Number: AK4480
• Description: High Performance 114dB 32-Bit DAC
• Manufacturer: AKM [Asahi Kasei Microsystems]

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The soft mute operation is performed at digital domain. When the SMUTE pin goes to “H” or the SMUTE bit set to “1”,
the output signal is attenuated by −∞ during ATT_DATA × ATT transition time from the current ATT level. When the
SMUTE pin is returned to “L” or the SMUTE bit is returned to “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 −∞ after starting the operation, 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:
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The AK4480 should be reset once by bringing the PDN pin = “L” upon power-up. The analog block exits power-down
mode by MCLK input and the digital block exits power-down mode after the internal counter counts MCLK for 4/fs.
MS1146-E-03
(1) ATT_DATA × ATT transition time. For example, this time is 1020LRCK cycles (1020/fs) at ATT_DATA=255 in
(2) The analog output corresponding to the digital input has group delay (GD).
(3) If the soft mute is cancelled before attenuating −∞ after starting the operation, the attenuation is discontinued
Soft Mute Operation (PCM and DSD)
(4) When the input data for each channel is continuously zeros for 8192 LRCK cycles, the DZF pin for each channel
System Reset
Normal Speed Mode.
goes to “H”. The DZF pin immediately returns to “L” if input data are not zero.
and returned to ATT level by the same cycle.
A ttenuation
A O U T
D ZF pin
S M U T E pin or
S M U T E bit
AT T _Level
-∞
(1)
Figure 12. Soft Mute Function
8192/fs
(4)
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G D
(2)
(1)
G D
(2)
(3)
[AK4480]
2012/01