[AK4438]
■ Soft Mute Operation
The soft mute operation is performed at digital domain. When the SMUTE pin goes to “H” or set SMUTE
bit 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 , 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.
SMUTE pin or
SMUTE bit
(1)
(1)
ATT_Level
Attenuation
(3)
-
GD
(2)
GD
(2)
AOUT
(4)
8192/fs
DZF pin
Notes:
(1) ATT_DATA ATT transition time. For example, this time is 4080LRCK cycles at ATT_DATA=255 in
Normal Speed Mode.
(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 and returned to ATT level by the same cycle.
(4) When the input data for a zero detection channel is continuously zeros for 8192 LRCK cycles, the
DZF pin goes to “H”. The DZF pin immediately returns to “L” if input data are not zero.
Figure 30. Soft Mute Function and Zero Detection
016001925-E-00
2016/03
- 38 -
AKM [ ASAHI KASEI MICROSYSTEMS ]
