ak4671 AKM Semiconductor, Inc., ak4671 Datasheet - Page 74

• Manufacturer Part Number: ak4671
• Description: Stereo Codec With Mic/rcv/hp-amp
• Manufacturer: AKM Semiconductor, Inc.

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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
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).
MS0666-E-00
Digital Output Volume
OVTM bit
0
1
(default)
Table 37. Transition Time Setting of Digital Output Volume
Transition time between DVL/R7-0 bits = 00H and FFH
1061/fs
Setting
256/fs
OVL/R7-0
Table 36. Digital Volume Code Table
FDH
FEH
FFH
00H
01H
02H
18H
:
:
- 74 -
MUTE ( −∞ )
− 114.5dB
− 115.0dB
+12.0dB
+11.5dB
+11.0dB
fs=8kHz
133ms
32ms
Gain
0dB
:
:
fs=44.1kHz
0.5dB
Step
24ms
6ms
(default)
(Table
37). When
[AK4671]
2007/10