AK4679EG Datasheet, PDF (93/220 Pages) Asahi Kasei Microsystems – 24bit Stereo CODEC with DSP and MIC/RCV/HP/SPK/LINE-AMP

[AK4679]
(2-3) Dynamic Volume Control Curve
The inflection points of the DVLC curve is set by three coordinate values (VM1X5-0, VM1Y5-0, VM2X5-0, VM2Y5-0,
VM3X4-0 and VM3Y4-0 bits). The setting of three inflection points are calculated the values of (X1_M, Y1_M), (X2_M,
Y2_M), (X3_M, Y3_M) in dB. The inflection points should be set in such a way that VM1X ≤ VM2X ≤ VM3X, VM1Y ≤
VM2Y ≤ VM3Y. And the each slope is set by M1G6-0, M2G6-0, M3G6-0 and M4G6-0 bits. X4_M is fixed full-scale, Y4_M
is calculated by the M4G value. The initial value of the DVLC gain is set by the M1G. When the HPF and LPF is bypass
(DMHPF1-0 = DMLPF1-0 bits = “00”), the audio data passes this block by 0dB gain.
Full scale
(X3_M, Y3_M)
(X2_M, Y2_M) _M3G
M4G
(X4_M, Y4_M)
(X1_M, Y1_M)
M2G
M1G
(0, 0)
DVLC Input Level
Full scale
Figure 72. DVLC Curve for Middle Frequency Range
VM1X/Y5-0 bits Dynamic Volume Control Point
VM2X/Y5-0 bits
[dBFS]
Step
00H
0
(default)
01H
−1.5
02H
−3.0
1.5dB
:
:
2EH
−69.0
2FH
−70.5
30H
N/A
:
:
N/A
3FH
N/A
Table 55. DVLC Point Setting for X/Y1, X/Y2 (N/A: Not available)
VM3X/Y4-0 bits
00H
01H
02H
:
1EH
1FH
Dynamic Volume Control Point
[dBFS]
Step
0
−1.5
−3.0
1.5dB
:
−45.0
−46.5
Table 56. DVLC Point Setting for X/Y3
(default)
MS1402-E-06
- 93 -
2013/02