Circuit Diagrams; Smps 1 Circuit Diagram - LG RH1777 Service Manual

CIRCUIT DIAGRAMS

1. SMPS 1 CIRCUIT DIAGRAM

12
No Power
BD101, TH101 is Defective
11
10
9
S/W Error
IC101 is Defective
8
7
6
No Power
F101 is Defective
5
4
3
2
1 NOTE) Warning
NOTES) Symbol denotes AC ground.
NOTE) Parts that are shaded are critical
NOTE) With respect to risk of fire or
NOTES) Symbol denotes DC chassis ground.
NOTE) electricial shock.
A B C D
5V No Power
D125 is Defective
No Power
D102 is Defective
5.3VA No Power
D128 is Defective
Switching Error
IC102,IC103 are Defective
E F G H I
3-43
IMPORTANT SAFETY NOTICE
WHEN SERVICING THIS CHASSIS, UNDER NO CIR-
CUMSTANCES SHOULD THE ORIGINAL DESIGN BE
MODIFIED OR ALTERED WITHOUT PERMISSION
FROM THE LG ELECTRONICS CORPORATION. ALL
COMPONENTS SHOULD BE REPLACED ONLY WITH
TYPES IDENTICAL TO THOSE IN THE ORIGINAL CIR-
FD(+)FD(-) No Power
D121 is Defective
-28VA No Power
D122 is Defective
13.5VA No Power
D124 is Defective
3.8VA No Power
D127 is Defective
33VA No Power
D125 is Defective
5V No Power
IC156, IC155 are Defective
J K L M
3-44
CUIT. SPECIAL COMPONENTS ARE SHADED ON THE NOTE :
SCHEMATIC FOR EASY IDENTIFICATION. 1. Shaded( ) parts are critical for safety. Replace only
THIS CIRCUIT DIAGRAM MAY OCCASIONALLY DIF- with specified part number.
FER FROM THE ACTUAL CIRCUIT USED. THIS WAY, 2. Voltages are DC-measured with a digital voltmeter
IMPLEMENTATION OF THE LATEST SAFETY AND during Play mode.
PERFORMANCE IMPROVEMENT CHANGES INTO
THE SET IS NOT DELAYED UNTIL THE NEW SERVICE
LITERATURE IS PRINTED.
(W, NTSC)
N O P Q R S T