AK4683_07 Datasheet, PDF (38/84 Pages) Asahi Kasei Microsystems – Asynchronous Multi-Channel Audio CODEC with DIR/T

[AK4683]
■ Digital Volume Control
The AK4683 has channel-independent digital volume control (256 levels, 0.5dB step). The ATTAD7-0 bit set the
volume level of each ADC channel (Table 35), ATTDA7-0 set each DAC channel (Table 36).
ATTAD7-0
00H
01H
02H
:
2FH
30H
31H
FEH
FFH
Attenuation Level
+24dB
+23.5dB
+22.0dB
:
+0.5dB
0dB
-0.5dB
:
-103dB
MUTE (-∞)
(default)
Table 35.ADC Digital Volume
ATTDA7-0
00H
01H
02H
:
17H
18H
19H
FEH
FFH
Attenuation Level
+12dB
+11.5dB
+11.0dB
:
+0.5dB
0dB
-0.5dB
:
-115dB
MUTE (-∞)
(default)
Table 36.DAC Digital Volume
Transition time between set values of ATTAD7-0 (ATTDA7-0) bits can be selected by ATSAD (ATSDA) bits (Table
37, Table 38). Transition between set values of Mode 0 and Mode 1is the soft transition. Therefore, the switching noise
does not occur in the transition.
Mode
0
1
ATSAD
0
1
ATT speed
1061/fs
256/fs
(default)
Table 37. Transition time between set values of ATTAD7-0 bits (ADC)
Mode
0
1
ATSDA
0
1
ATT speed
1061/fs
256/fs
(default)
Table 38. Transition time between set values of ATTDA7-0 bits (DAC)
The transition between set values is soft transition of 1061 levels in Mode 0. It takes 1061/fs (24ms@fs=48kHz) from
00H to FFH(MUTE) in Mode 0. If PDN pin goes to “L”, the ATTAD7-0(ATTDA7-0) bits are initialized to 30H(18H).
The ATTs goes to their default value when RSTN1 bit = “0”. When RSTN1 bit return to “1”, the ATTs fade to their
current value.
MS0427-E-02
- 38 -
2007/04