LG KG920 - Main Microphone

3. TECHNICAL BRIEF
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3.12 Main Microphone
The microphone is placed to be contacted to KEYPAD PCB through FPCB.
The audio signal is passed to AIN1P and AININ pins of AD6535. The voltage supply VMIC is output from
AD6535, and is a biased voltage for the AIN1P. The AIN1P and AIN1N signals are then A/D converted
by the voiceband ADC part of AD6535.
The digitized speech (PCM 8KHz ,16KHz) is then passed to the DSP section of AD6527 for processing
(coding, interleaving etc).
CLOSE TO AD6535
C146
39p
C141
39p
4.7
R111
R109
4.7
NC_R12
R12
T8
SGND1
R8
SGND2 DGND
C2
GPI
LGND
N15
M2
AIN1N
P16
AIN1P
AIN2N
R15
AIN2P
P15
AIN3L
R13
R14
AIN3R
AOUT1N
K15
AOUT1P
J15
AOUT2N1
T9
AOUT2N2
R9
AOUT2P1
R11
AOUT2P2
T11
AOUT3L
J16
AOUT3R
K16
B16
AGND1
A11
AGND2 AGND3
L15
R16
39p
C139
39p
C142
C149
39p
C145
39p
39p
C148C147
39p
C144
39p
C140
39p
39p
C150
SPK_P_SM
RCV_P
RCV_N
AUX_OUT_L
MIC_IN-
MIC_IN+
AUX_MIC_N
AUX_MIC_P
AUX_OUT_R
Figure 3-33.
MAIN MICROPHONE
C416
39p
2.2K
R427
100
R422
39p
C420
R417
1K
2V5_VMIC
C423 0.1u
C413
39p
10u
C421
R426
100
C425
39p
2.2K
R420
0
R423
39p
C426
MIC_IN+
MIC_IN-
MIC_P
MIC_N
VA102
EVLC14S02050 EVLC14S02050
VA101
MIC1
OBG-415L42-C33LH
MIC_P
MIC_N