LG B2050, Service Manual

Page: 42 / 133

3. TECHNICAL BRIEF
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3.9 Microphone
The microphone is placed to the front cover and contacted to main PCB. The audio signal is
passed to AIN2P and AIN2N pins of AD6535. The voltage supply VMIC is output from AD6537B,
and is a biased voltage for the AIN2P. The AIN2P and AIN2N signals are then A/D converted by
the voiceband ADC part of AD6537B.The digitized speech (PCM 8KHz ,16KHz) is then passed
to the DSP section of AD6527 for processing (coding, interleaving etc).
Figure 3-28 Connection between Microphone and AD6537B
C I M O T E S O L C
K 1
0 0 2 R
0 0 1
0 1 2 R
0
8 0 2 R
K 2 . 2
3 0 2 R
3 1 2 C
p 9 3
p 9 3
9 0 2 C
0 0 2 - 2 0 M 5 L V A
0 0 2 A V
p 9 3
1 0 2 C
p 9 3
4 1 2 C
C I M V _ 5 V 2
0 0 2 - 2 0 M 5 L V A
1 0 2 A V
0 1 2 C
p 9 3
0 0 1
7 0 2 R
0 0 2 C I M
L 3 3 C - 2 4 L 5 1 - 4 B O
1
2
1 1 2 C
u 1 . 0
K 2 . 2
4 1 2 R
u 0 1
2 0 2 C
N _ C I M
P _ C I M
3.10 Main Speaker
In the case of B2050, The main speaker is driven directly from AD6537B AOUT1P and
AOUT1N pins and the gain is controlled by the PGA in an AD6537B.
R E V I E C E R
R E K A E P S
L E S _ K P S
N O I T C E L E S R E K A E P S / R E V I E C E R
T U P T U O
H G I H
W O L
0 0 2 N C
1
2
6
4
1 N I
8
2 N I
1 C N
5
7
2 C N
2
1 O N
0 1
2 O N
1
+ V
2 R M 4 8 6 4 S A L N
2 0 2 U
1 M O C
3
2 M O C
9
D N G
T A B V
8 9 2 C
A N
A N
9 9 2 C
0 2 2 C
u 0 1
P _ K P S
N _ K P S
N _ C E R L E S _ K P S
P _ C E R