AK4671_10 Datasheet, PDF (58/166 Pages) Asahi Kasei Microsystems – Stereo CODEC with MIC/RCV/HP-AMP

[AK4671]
■ MIC Gain Amplifier
The AK4671 has a gain amplifier for microphone input. The gain of MIC-Amp Lch and Rch is independently selected by
the MGNL3-0 and MGNR3-0 bits (Table 19). The typical input impedance is 42kΩ(typ)@MGNL/R0 bits = “0” or
30kΩ(typ)@MGNL/R0 bits = “1”.
Mode
0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
MGNL3
MGNR3
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
MGNL2
MGNR2
MGNL1
MGNR1
MGNL0
MGNR0
Input Gain
0
0
0
N/A
0
0
1
−12dB
0
1
0
−9dB
0
1
1
−6dB
1
0
0
−3dB
1
0
1
0dB
1
1
0
+3dB
1
1
1
+6dB
0
0
0
+9dB
0
0
1
+12dB
0
1
0
+15dB
0
1
1
+18dB
1
0
0
+21dB
1
0
1
+24dB
1
1
0
+27dB
1
1
1
+30dB
Table 19. Mic Input Gain (N/A: Not available)
Input Resistance
N/A
30kΩ
42kΩ
30kΩ
42kΩ
30kΩ
42kΩ
30kΩ
42kΩ
30kΩ
42kΩ
30kΩ
42kΩ
30kΩ
42kΩ
30kΩ
(default)
MS0666-E-02
- 58 -
2010/06