LG 6870R9731AA PSU Schematic

3-20 3-21

BLOCK DIAGRAMS

1. POWER(SMPS) BLOCK DIAGRAM

BD101

T101

TRANS

R101

BR BL

(BK)(WH)

C103

FUSE

(F101)

NOISE FILTER

BLOCK

(C101,L102,

C102)

PHOTO COUPLER

(IC102)

ERROR

AMP

(IC103)

SNUBBER

BLOCK (D101,C105 C106,R104)

DRIVE & S/W BLOCK

(IC101, D102, R105,

C104, C109 , C135)

Y-CAP

C111

Y-CAP

C110

FEED-BACK

BLOCK R112,R113, C133,R114.

R115,R116

R117)

RECTIFIER &

SMOOTING BLOCK

(D110,C123,C163,

R133,L122,C126)

RECTIFIER &

SMOOTING BLOCK

(D118,D112,C129,

C131,L124,L125)

RECTIFIER &

SMOOTING BLOCK

(D111,C127,L123,

C128)

RECTIFIER &

SMOOTING BLOCK

(D113,C132,R119)

CAP VCC

D115

D117

DRUM VCC

12V

5.3VA

3.3V

33V

12V REG BLOCK

(Q156,ZD103,C151,

R150,R153,C152)

8V REG BLOCK

(D114,IC151,R170,

C154,C159)

5V S/W BLOCK

(Q160,C155,D121,

R157,R158,R159,R160)

3.3V REG BLOCK

(IC152,C153,R156)

33V S/W BLOCK

(Q161,R154,R155,

R177)

5V S/W BLOCK

(Q163,C162,R173,

Q164)

PWR CTL'H'

SW5V

9V REG BLOCK

(Q165,ZD171,C171,

R174,R175,R176)

PWR CTL BLOCK

(Q162,C161,R164,

R163)

657 8

DVW-7000

3-32 3-33

NOTES) Symbol denotes AC ground.

NOTES) Symbol denotes DC chassis ground.

NOTE) Warning

NOTE) Parts that are shaded are critical NOTE) With respect to risk of fire or NOTE) electricial shock.

SR14370A

DVW-7000

(DVW-7000 Without)

CIRCUIT DIAGRAMS

1. POWER(SMPS) CIRCUIT DIAGRAM 1

Switching Error. IC101 is defective.

Switching Error. IC103, 102 are defective.

2.5V, 3.3V no power. D111 is defective.

No Power. F101 is defective.

5.3VA no power. D112 is defective.

33V no power. D113 is defective.

No power. BD101, R101 are defective.

12VA no power. D110 is defective.

IMPORTANT SAFETY NOTICE

WHEN SERVICING THIS CHASSIS, UNDER NO CIRCUMSTANCES SHOULD THE ORIGINAL DESIGN BE MODIFIED OR ALTERED WITHOUT PERMISSION FROM THE GO VIDEO ELECTRONICS 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.

NOTE :

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.

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