LG U990 Service Manual page 127

4. TROUBLE SHOOTING
U504
MIDI_3.3V
C565 C566
4.7u 1u
C570
1u
LGE Internal Use Only
C562
R522
1 12
PVDD OUTL
2 11
C1P U504 SVSS
MAX9722BETE
3 10
PGND U504 OUTR
4 9
C1N SVDD2
C577
1u
Schematic of voice path
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FB502
FB503
C578
R529
HP_AMP_EN
HP_EAR_L
FB502 600
R524
68
FB503 600
R525
PQ
68
PQ
HP_EAR_R
Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes
MIDI_EAR_L
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