AK4706 Datasheet, PDF (28/53 Pages) Asahi Kasei Microsystems – 2ch 24bit DAC with AV Switch & HD/SD Video Filter

ASAHI KASEI
[AK4706]
„ Volume Control #1 (Main Volume)
The AK4706 has main volume control (Volume #1) as shown in Table 12.
(02H: D5-D0)
L5
L4
L3
L2
L1
L0
1
0
0
0
1
0
1
0
0
0
0
1
1
0
0
0
0
0
0
1
1
1
1
1
…
…
…
…
…
…
0
0
0
0
0
1
0
0
0
0
0
0
Note: The output must not exceed 3Vrms.
Table 12. Volume #1
Gain
+6dB
+4dB
+2dB
0dB (default)
…
-60dB
Mute
When the MOD bit = “1”(default), changing levels don’t have pop noise. MDT1-0 bits select the transition time (see
Table 13). When the new gain value 1EH(-2dB) is written to gain resistor while the actual (stable) gain is 1FH(0dB), the
gain changes to 1EH(-2dB) within the transition time selected by MDT1-0 bits. The AK4706 compares the actual gain to
the value of gain register after finishing the transition time, and re-changes the actual gain to new resister value within the
transition time if the register value is different from the actual gain when compared. When the MOD bit = “0” then there
is no transition time and the gain changes immediately. This change may cause a click noise.
WR
[Gain=1EH]
WR
[Gain=1DH]
WR
[Gain=1CH]
Gain Register
Actual Gain
1FH
1EH
compare
1FH (to 1EH)
1EH
1DH
1CH
compare compare
(to 1DH) (to 1CH)
1CH
1DH
Transition Time (256/fs to 2048/fs. pop free.)
Figure 7. Volume Change Operation (MOD bit = “1”)
MDT1
0
0
1
1
MDT0
Transition Time
0
256/fs
1
512/fs
0
1024/fs
1
2048/fs (default)
Table 13. Volume Transition Time
MS0507-E-00
- 28 -
2006/05