AK4691 Datasheet, PDF (49/80 Pages) Asahi Kasei Microsystems – 4ch ADC + 2ch DAC with MIC/HP/SPK-AMP

[AK4691]
■ Digital Output Volume
The AK4691 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 placed 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 a soft transit function. The
DVTM bit sets the transition time between set values of DVL/R7-0 bits as either 1061/fs or 256/fs (Table 40). When
DVTM bit = “0”, a soft transition between the set values occurs (1062 levels). It takes 1061/fs (=22.1ms@fs=48kHz)
from 00H (+12dB) to FFH (MUTE).
DVL/R7-0 bits
Gain
00H
+12.0dB
01H
+11.5dB
02H
+11.0dB
:
:
18H
0dB
(default)
:
:
FDH
−114.5dB
FEH
−115.0dB
FFH
MUTE (−∞)
Table 39. Digital Volume Code Table
DVTM bit
0
1
Transition time between DVL/R7-0 bits = 00H and FFH
Setting
fs=8kHz
fs=48kHz
1061/fs
133ms
22.1ms
256/fs
32ms
5.3ms
Table 40. Transition Time Setting of Digital Output Volume
(default)
MS0672-E-00
- 49 -
2007/11