ASAHI KASEI
[AK4140]
Stereo Volume Control
The AK4140 has a digital output volume (25 levels, 1dB step, Mute). The L4-0 and R4-0 bits can set the volume. The
volume is placed in front of a stereo matrix block. The input data of the digital volume is changed from +12 to –12dB or
MUTE. When the VOLC bit = “1” (default), the L4-0 bits control both Lch and Rch attenuation levels. When the VOLC
bit = “0”, the L4-0 bits control Lch level and R4-0 bits control Rch level. This volume has a soft transition function. When
changing levels, transitions are executed with soft changes; thus no switching noise occurs during these transitions. The
transition time of 1 level and all levels are shown in Table 17.
Transition Time
1 Level
8LRCK
+12 to -12
192LRCK
Table 17. ATT Transition Time
L4
1
L3
1
L2
0
L1
0
L0
1
Gain
+12dB
+11dB
…
1
1
0
0
0
…
0
…
1
…
1
…
1
…
0
+1dB
0
1
1
0
1
0dB
0
1
1
0
0
-1dB
…
0
0
…
0
0
…
0
0
…
1
0
…
0
1
…
-11dB
-12dB
Mute (default)
0
0
0
0
0
Table 18. Volume (Lch)
R4
1
R3
1
R2
0
R1
0
R0
1
Gain
+12dB
+11dB
…
1
1
0
0
0
…
0
…
1
…
1
…
1
…
0
+1dB
0
1
1
0
1
0dB
0
1
1
0
0
-1dB
…
0
0
…
0
0
…
0
0
…
1
0
…
0
1
…
-11dB
-12dB
Mute (default)
0
0
0
0
0
Table 19. Volume (Rch)
MS0547-E-01
2007/03
- 27 -
AKM [ ASAHI KASEI MICROSYSTEMS ]
