AK4671_10 Datasheet, PDF (74/166 Pages) Asahi Kasei Microsystems – Stereo CODEC with MIC/RCV/HP-AMP

[AK4671]
■ Digital Output Volume
The AK4671 has a digital output volume (256 levels, 0.5dB step, Mute). The volume can be set by the OVL7-0 and
OVR7-0 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 OVOLC bit = “1”, the OVL7-0 bits control both Lch and Rch attenuation levels. When the OVOLC bit
= “0”, the OVL7-0 bits control Lch level and OVR7-0 bits control Rch level. This volume has a soft transition function.
The OVTM bit sets the transition time between set values of OVL/R7-0 bits as either 1061/fs or 256/fs (Table 37). When
OVTM bit = “0”, a soft transition between the set values occurs (1062 levels). It takes 1061/fs (=24ms@fs=44.1kHz)
from 00H (+12dB) to FFH (MUTE).
(default)
OVL/R7-0
Gain
00H
+12.0dB
01H
+11.5dB
02H
+11.0dB
:
:
18H
0dB
:
:
FDH
−114.5dB
FEH
−115.0dB
FFH
MUTE (−∞)
Table 36. Digital Volume Code Table
Step
0.5dB
OVTM bit
Transition time between DVL/R7-0 bits = 00H and FFH
Setting
fs=8kHz
fs=44.1kHz
0
1061/fs
133ms
24ms
1
256/fs
32ms
6ms
Table 37. Transition Time Setting of Digital Output Volume
(default)
MS0666-E-02
- 74 -
2010/06