Speaker Trouble - LG C1100 Service Manual

4.7 Speaker Trouble

Test Points
CN201
C410
Circuit Diagram
VMEM
R401 0 1
13MHZ_MIDI
4
MIDI_RESET
30
ADD00
31
RD
29
MIDI_CS
5
R403
10K
28
WR
3
MIDI_INT
27
DATA08
26
DATA09
25
DATA10
24
DATA11
23
DATA12
22
DATA13
21
DATA14
20
DATA15
C401
R408 3.3K
6
1000p
C402 0.1u
9
R412
32 SDOUT
10K
R413
7
0
C403 0.1u
8
U401
R404
C404
R420
These five components
make up the amplifier and
the filter stage of melody.
[C404 R402 C405 R404 R417]
U401
YMU759B
11
CLK1 HPOUT_R
10
_RST
HPOUT_L
C404
A0
R402
12
EQ1
_RD
0.01u
_CS 39K
13
EQ2
IFSEL
C405 R404
_WR
100p 0
_IRQ
R417 150K
14
EQ3
D0
2
D1 EXT1
19
D2 EXT2
D3
D4
17
D5
SPOUT1
D6
Speaker path
VBAT
D7
PLLC SPOUT2
18
VREF
R410 0
SPVDD 15
VDD C408
0.1u
16
VSS SPVSS
(16 Poly MIDI)
vibrator
C417
C405
Figure 4-19.
VMEM
C409 39p
R405
SPKN
NA
R406
SPKP
1
NA
R407
2
0
3
R409
4
0
5
C406 C407
Closed to Analog SW
47p 47p
R414
RECP
4.7 receiver path
R416
RECN
4.7
C411 C412
47p 47p
- 67 -
4. Trouble Shooting
Soldering
check
Analog switch for select audio
path or midi path.
To the speaker at LCD
U402
module via CN201.
MAX4684EUB
10
V+ NO2
9
NO1 COM2
8
COM1 IN2
7
IN1 NC2
C410 47p
6
NC1 GND
SPK_RCV_SEL
R415 100K
Speaker
SPK_REC_N
SPK_REC_P