AK4635 AKM [Asahi Kasei Microsystems], AK4635 Datasheet - Page 38

• Manufacturer Part Number: AK4635
• Description: 16-Bit Mono CODEC with ALC & MIC/SPK/Video-AMP
• Manufacturer: AKM [Asahi Kasei Microsystems]

■
The AK4635 has a Gain Amplifier for Microphone input. These gains are selected by the MGAIN3-0 bit. The typical
input impedance is 30kΩ.
■
The MPI pin supplies power for the Microphone. This output voltage is proportional to 0.8 x AVDD typically and the
load resistance is minimum 2kΩ. No capacitor must not be connected to the MPI pin, directly.
Rev. 0.6
MIC Gain Amplifier
MIC Power
MGAIN3 bit
0
0
0
0
0
0
0
0
1
1
1k
1k
≥ 2k
MICP pin
MICNpin
MGAIN2 bit
MIC pin
MPI pin
MPI pin
0
0
0
0
1
1
1
1
0
0
Figure 37. MIC Differential Input Circuit
Others
Figure 38. MIC Block Circuit
MGAIN1 bit
MIC-Power
Table 20. Input Gain
MIC-Power
MIC-Amp
MIC-Amp
0
0
1
1
0
0
1
1
0
0
- 38 -
A/D
A/D
MGAIN0 bit
HPF
HPF
0
1
0
1
0
1
0
1
0
1
AK4635
AK4635
Audio
Audio
I/F
I/F
Input Gain
+20dB
+26dB
+32dB
+10dB
+17dB
+23dB
+29dB
+3dB
+6dB
0dB
N/A
STDO pin
STDO pin
BICK pin
BICK pin
FCK pin
FCK pin
(Figure
(default)
38)
[AK4635]
2007/10