[AK4685]
L/R channels of the analog outputs (LOUT+/-, ROUT+/- pins) can be muted independently by AMT1LN or AMT1RN
bits = “0”. When those channels are muted, transition time is depending on AMT2-0 bits setting. Each mute is cancelled
by AMT1LN / AMT1RN bit = “1”. It is digitally-processed, and the output attenuation gradually changes to the ATT
level during ATT_DATA x ATT transition time. (Table 16)
AMT1LN/1RN bit
(1)
(3)
ATT Level
Digital Attenuation
-∞
GD
(2)
AOUT
(1) “L” time of 20ms or more is needed.
(2) The soft mute transition time by analog processing is depending on the AMTS2-0 bits setting.
(3) ATT_DATA x ATT transition time (Table 16). In case of MODE0 and ATS2-0 bits =“00H”, the transition time of
ATT value from FFH(0dB) to 00H(MUTE) is 1061/fs.
Figure 16. Mute Sequence Example (AMT1LN/1RN bit)
When AMT1LN=AMT1RN bit = “0”, the analog outputs (DACL+/-, DACR+/- pins) are attenuated in soft transition as
well as when the MT1N pin = “L”. The analog block becomes power-down mode after the soft transition is completed,
and VCON is output from the analog outputs.
When a one of or both AMT1L and AMT1RN bits are set to “1”, the analog block returns to normal operation. The mute
on the corresponding channel is cancelled and the output attenuation gradually changes to the ATT level during
ATT_DATA x ATT transition time. (Table 16)
When the AMT2LN=AMT2RN bit = “0”, the analog and headphone blocks become power-down mode, and ground level
(VSS5) is output from these outputs as well as when the MT2N pin = “L”. Transition time is controlled by AMT2-0 bits.
The data inputs and DAC clocks must not be stopped before the soft transition complete.
When t both AMT2L and AMT2RN bits are set to “1”, the analog and headphone blocks return to normal operation. The
mute is cancelled and the output attenuation gradually changes to the ATT level during ATT_DATA x ATT transition
time. (Table 16)
MS1106-E-00
2009/08
- 34 -
AKM [ ASAHI KASEI MICROSYSTEMS ]
