AK4953A Datasheet, PDF (49/96 Pages) Asahi Kasei Microsystems – 24bit Stereo CODEC with MIC/HP/SPK-AMP

[AK4953A]
■ Output Digital Volume 2
The AK4953A has a digital output volume (256 levels, 0.5dB step, Mute). The volume can be set by the DVL7-0 and
DVR7-0 bits. The volume is included in front of a DAC block. The input data of DAC is changed from +12 to –115dB or
MUTE. When the DVOLC bit = “1”, the DVL7-0 bits control both Lch and Rch attenuation levels. When the DVOLC bit
= “0”, the DVL7-0 bits control Lch level and DVR7-0 bits control Rch level. This volume has soft transition function.
Therefore no switching noise occurs during the transition. The DVTM1-0 bits set the transition time between set values
of DVL/R7-0 bits (from 00H to FFH) as either 256/fs, 1024/fs or 2048/fs (Table 42). When DVTM1-0 bits = “01”, a soft
transition between the set values occurs (1024 levels). It takes 1024/fs (=23ms@fs=44.1kHz) from 00H (+12dB) to FFH
(MUTE).
DVL7-0 bits
DVR7-0 bits
Gain
Step
00H
+12.0dB
01H
+11.5dB
02H
+11.0dB
:
:
0.5dB
18H
0dB
(default)
:
FDH
-114.5dB
FEH
-115.0dB
FFH
Mute (- ∞)
Table 41. Output Digital Volume2 Setting
DVTM1 DVTM0 Transition Time between DVL/R7-0 bits = 00H and FFH
bit
bit
Setting
fs=8kHz
fs=44.1kHz
fs=96kHz
0
0
256/fs
32ms
5.8ms
2.7ms
0
1
1024/fs
128ms
23ms
11ms
(default)
1
0
2048/fs
256ms
46ms
21ms
1
1
N/A
Table 42. Transition Time Setting of Output Digital Volume2 (N/A: Not available)
MS1252-E-00
- 49 -
2010/10