File name LG_2200N.pdfCIRCUIT DIAGRAM
1. POWER(SMPS) CIRCUIT DIAGRAM
IMPORTANT SAFETY NOTICE WHEN SERVICING THIS CHASSIS, UNDER NO CIRCUMSTANCES SHOULD THE ORIGINAL DESIGN BE MODIFIED OR ALTETED WITHOUT PERMISSION FROM THE ZENITH ELECTRONICS CORPORATION ALL COMPONENTS SHOULD BE REPLACED ONLY WITH TYPES IDENTICAL TO THOSE IN THE ORIGI-
NAL CIRCUIT SPECIAL COMPONTS ARE SHADED ON NOTE : THE SCHEMATIC FOR EASY IDENTIFICATION. 1. Shaded( ) parts are critical for safety. Replace only THIS CIRCUIT DIAGRAM MAY OCCASIONALLY DIFwith 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.
IC902 is defective. 8V Power Line dead.
Q908, R928, D913 and Q909 are defective. 5V Power Line dead.
IC903 PIN3 (AC110V, PLAY)
IC901 PIN3 (AC110V, STAND-BY)
Q901 and Q902 are defective. FLD(+), FLD(-) are dead.
IC901 is defective. Power dead.
C927, R918, R922 and IC905 are defective. Power dead.
Q903, Q904 are defective. Power control is abnormal.
NOTES) NOTES) NOTES) NOTES)
Warning Parts that are shaded are critical With respect to risk of fire or electricial shock.
3-18
3-19
2. RF & DVD DSP CIRCUIT DIAGRAM
Q202 is defective. DVD LD will not be on. IC204 is defective being slipped during search.
IC209 is defective AD Converter Error
TZC Mirr. Generator
AD Ref. Voltage Gen
RF/TE/FE Signal generation
Q203 is defective CD LD will not be on
Digital Servo DSP/ CD Decoder
Spindle Low Pass Filter
DRAM
3.3V Regulator
IC219 is defective Servo will not operate
IC403 is defective No Spindle Full Speed
T.E F.E
R.F TRACKING LOOP
FOCUS LOOP SLED LOOP
SPINDLE LOOP
3-20
3-21
3. DRIVE CIRCUIT DIAGRAM
SPINDLE
MOTOR DRIVE
SPINDLE TRACKING DOOR
FOCUS SLIED
3-22
3-23
4. MPEG & ENCODER CIRCUIT DIAGRAM
2 1 3 4 6 7 8 9 10 11 12 13
No power on 3.3V Reg.
5
No power on No power on µ-com->MPEG address
ROM
VIDEO ENCODER
14 15
The screen is distorted(DVD) Over 3V->Data error. GND:OK No VCD screen display(option). No CD sound out. No DVD screen display
16
Over 3V->Data error. GND:OK (CD/VCD option) No power on No Audio(check clock)
MPEG2 DECODER
No 5.1CH Audio
18
No 2CH Audio Audio signal doesn't appear No screen No power on µ-com->MPEG command data No power on over 3V: normal
19 20 21 17 25 22
16M SDRAM 16M SDRAM VIDEO ENCODER
No power on Check 89MHz Video Mute doesn't operate in power on/off No Pb output No Pr output No Y output
23
24
No composite video output No Luminance output in Y/C Video No Chrominance output in Y/C Video No power on No power on
CLOCK
VIDEO
26
3-24
3-25
5. AUDIO CIRCUIT DIAGRAM
IC712, 713 are defective Audio bad
Q601 is defective 5.1CH FL/FR Audio out bad IC704 is defective 2CH Audio out bad Q705 is defective 2CH Audio out bad
IC604 is defective 5.1CH FL/FR Audio out bad
IC705,706,707 are defective Audio POP noise o |