AK5373 Datasheet, PDF (16/53 Pages) Asahi Kasei Microsystems – 24-bit Stereo ADC with USB Interface

[AK5373]
■ MIC Gain Amplifier
The AK5373 has a gain amplifier for microphone inputs. The gain of MIC-Amp is selected by the MGAIN2-0 pins or
MGAIN2-0 bits (Table 2).
MGAIN2
pin
L
L
L
L
H
H
H
H
MGAIN1
pin
L
L
H
H
L
L
H
H
MGAIN0 MGAIN2 MGAIN1 MGAIN0
pin
bit
bit
bit
0
0
0
0
0
1
0
1
0
L
0
1
1
1
0
0
1
0
1
1
1
0
1
1
1
H
L
H
L
x
x
x
H
L
H
Table 2. Mic Input Gain (x: Don’t care)
Input Gain
0dB
0dB
+6dB
+12dB
+18dB
+24dB
+30dB
+36dB
0dB
+6dB
+12dB
+18dB
+24dB
+30dB
+36dB
■ MIC Power
When PMMP bit = “1”, the MPWR pin supplies power for the microphone. This output voltage is typically 2.2V and the
output current is maximum 2.0mA. In case of using two sets of stereo full-differential microphones, the load resistance is
minimum 1kΩ for each channel. Any capacitor must not be connected directly to the MPWR pin (Figure 14).
PMMP bit
MPWR pin
0
Hi-Z
1
Output
Table 3. MIC Power
MIC Power
VREF
MPWR
AK5373
MI CLP
MI CLN
MI CRP
MI CRN
Mi crop hone
Mi crop hone
Figure 14. MIC Block Circuit
MS1202-E-00
- 16 -
2010/06