LG BD550, Service Manual

Page: 108 / 141

3-93 3-94
CIRCUIT DIAGRAMS
1. SMPS - POWER CIRCUIT DIAGRAM
WHEN SERVICING THIS CHASSIS, UNDER NO
CIRCUMSTANCES SHOULD THE ORIGINAL DESIGN
BE MODIFIED OR ALTERED WITHOUT PERMISSION
FROM THE LG CORPORATION. ALL COMPONENTS
SHOULD BE REPLACED ONLY WITH TYPES
IDENTICAL TO THOSE IN THE ORIGINAL CIRCUIT.
SPECIAL COMPONENTS ARE SHADED ON THE SCHEMATIC FOR EASY IDENTIFICATION. THIS
CIRCUIT DIAGRAM MAY OCCASIONALLY DIFFER
FROM THE ACTUAL CIRCUIT USED. THIS WAY,
IMPLEMENTATION OF THE LATEST SAFETY AND
PERFORMANCE IMPROVEMENT CHANGES INTO
THE SET IS NOT DELAYED UNTIL THE NEW SERVICE
LITERATURE IS PRINTED. 1. Shaded( ) parts are critical for safety. Replace only
with specified part number.
2. Voltages are DC-measured with a digital voltmeter
during Play mode.
IMPORTANT SAFETY NOTE :
A
1
2
3
4
5
6
7
8
9
10
11
12
B C D E F G H I J K L M N O P Q R S T
Warning
Parts that are shaded are critical with
respect to risk of fire or electrical shock.
CAUTION:
Danger if fuse is incorrectly replaced.
Replace only with the type identical to fuse rating
and(or) model name described in main label.
13VA No Power
D124 is Defective
No Power
D101,R101 are Defective
Switching Error
IC102,IC103 are Defective
S/W Error
IC101 is Defective
5.3VA No Power
D126,D127 are Defective
No Power
F101 is Defective
No Power
D104 is Defective