AK4613 Datasheet, PDF (44/69 Pages) Asahi Kasei Microsystems – 4/12-Channel Audio CODEC

[AK4613]
■ Digital Attenuator
AK4613 has a channel-independent digital attenuator (256 levels, 0.5dB steps). Attenuation level of each channel can be
set by each the ATT7-0 bits (Table 17).
ATT7-0
00H
01H
02H
:
7DH
7EH
7FH
FEH
FFH
Attenuation Level
0dB
-0.5dB
-1.0dB
:
-62.5dB
-63.0dB
-63.5dB
:
-127.0dB
MUTE (-∞)
(default)
Table 17. Attenuation level of digital attenuator
Transition time between set values of ATT7-0 bits can be selected by the ATS1-0 bits (Table 18). Transition between set
values is the soft transition in Mode1/2/3 eliminating switching noise in the transition.
Mode
0
1
2
3
ATS1
0
0
1
1
ATS0
0
1
0
1
ATT speed
4096/fs
2048/fs
512/fs
256/fs
(default)
Table 18. Transition time between set values of ATT7-0 bits
The transition between set values is a soft transition of 4096 levels in mode 0. It takes 4096/fs (85.3ms@fs=48kHz) from
00H(0dB) to FFH(MUTE). If the PDN pin goes to “L”, the ATTs are initialized to 00H. The ATTs also become 00H when
RSTN bit = “0”, and fade to their current value when RSTN bit returns to “1”.
MS1052-E-02
- 44 -
2010/03