ak5701 AKM Semiconductor, Inc., ak5701 Datasheet - Page 34

• Manufacturer Part Number: ak5701
• Description: 16-bit ?? Stereo Adc With Pll & Mic-amp
• Manufacturer: AKM Semiconductor, Inc.

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The AK5701 has a gain amplifier for microphone input. The gain of MIC-Amp is selected by the MGAIN1-0 bits
20). The typical input impedance is 60kΩ(typ)@MGAIN1-0 bits = “00” or 30kΩ(typ)@MGAIN1-0 bits = “01” or “10”.
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When PMMP bit = “1”, the MPWR pin supplies power for the microphone. This output voltage is typically 0.75 x AVDD
and the load resistance is minimum 0.5kΩ. In case of using two sets of stereo mic, the load resistance is minimum 2kΩ for
each channel. Any capacitor must not be connected directly to the MPWR pin
MS0404-E-02
MIC Gain Amplifier
MIC Power
Figure 37. Connection Example for Full-differential Mic Input (MDIF1/2 bits = “1”)
MIC Power
MGAIN1 bit
0
0
1
1
Table 20. Mic Input Gain (N/A: Not available)
PMMP bit
0
1
1k
1k
Figure 38. MIC Block Circuit
MGAIN0 bit
MPWR pin
IN1+ pin
IN1− pin
Table 21. MIC Power
MPWR pin
LIN1 pin
RIN1 pin
LIN2 pin
RIN2 pin
0
1
0
1
- 34 -
MPWR pin
Output
Hi-Z
Input Gain
+15dB
+30dB
0dB
N/A
MIC-Amp
(default)
AK5701
(Figure
(default)
Microphone
Microphone
Microphone
Microphone
38).
[AK5701]
2007/08
(Table