ak4368 AKM Semiconductor, Inc., ak4368 Datasheet - Page 27

• Manufacturer Part Number: ak4368
• Description: Dac With Built-in Pll & Hp-amp
• Manufacturer: AKM Semiconductor, Inc.

ASAHI KASEI
The AK4368 has a channel-independent digital attenuator (256 levels, 0.5dB step). This digital attenuator is placed before
the D/A converter. ATTL/R7-0 bits set the attenuation level (0dB to −127dB or MUTE) for each channel (Table 17). At
DATTC bit = “1”, ATTL7-0 bits control both channel’s attenuation levels. At DATTC bit = “0”, ATTL7-0 bits control
the left channel level and ATTR7-0 bits control the right channel level.
The ATS bit sets the transition time between set values of ATT7-0 bits as either 1061/fs or 7424/fs (Table 18). When the
ATS bit = “0”, a soft transition between the set values occurs(1062 levels). It takes 1061/fs (24ms@fs=44.1kHz) from
FFH(0dB) to 00H(MUTE). The ATTs are 00H when the PMDAC bit is “0”. When the PMDAC returns to “1”, the ATTs
fade to their current value. The digital attenuator is independent of the soft mute function.
MS0529-E-00
Digital Attenuator
Table 18. Transition time between set values of ATT7-0 bits
ATS
0
1
ATTR7-0
ATTL7-0
Table 17. Digital Volume ATT values
FDH
FCH
FFH
FEH
02H
01H
00H
0dB to MUTE
:
:
1061/fs
7424/fs
ATT speed
MUTE (−∞)
Attenuation
−126.5dB
−127.0dB
- 27 -
−0.5dB
−1.0dB
−1.5dB
0dB
:
:
1 step
29/fs
4/fs
Default
Default
[AK4368EG]
2006/07