LG HT306SF Service Manual

2-1
SECTION 2
ELECTRICAL
CONTENTS
ELECTRICAL TROUBLESHOOTING GUIDE ............................................................................................... 2-2
1. POWER SUPPLY CIRCUIT .................................................................................................................... 2-2
2. FRONT CIRCUIT (1/2) ............................................................................................................................ 2-3
3. FRONT CIRCUIT (2/2) ............................................................................................................................ 2-4
4. SYSTEM OPERATION FLOW ................................................................................................................ 2-5
5. TEST & DEBUG FLOW .......................................................................................................................... 2-6
6. AMP PROTECTION .............................................................................................................................. 2-12
7. AUDIO μ-COM CIRCUIT(DVD & AMP) ................................................................................................ 2-13
DETAILS AND WAVEFORMS ON SYSTEM TEST AND DEBUGGING .................................................. 2-14
1. SYSTEM 27 MHZ CLOCK, RESET, FLASH R/W SIGNAL .................................................................. 2-14
2. SDRAM CLOCK .................................................................................................................................... 2-15
3. TRAY OPEN/CLOSE SIGNAL .............................................................................................................. 2-16
4. SLED CONTROL RELATED SIGNAL (NO DISC CONDITION) .......................................................... 2-17
5. LENS CONTROL RELATED SIGNAL (NO DISC CONDITION) .......................................................... 2-18
6. LASER POWER CONTROL RELATED SIGNAL (NO DISC CONDITION) ......................................... 2-18
7. DISC TYPE JUDGEMENT WAVEFORMS ........................................................................................... 2-19
8. FOCUS ON WAVEFORMS................................................................................................................... 2-21
9. SPINDLE CONTROL WAVEFORMS (NO DISC CONDITION) ............................................................ 2-22
10. TRACKING CONTROL RELATED SIGNAL (SYSTEM CHECKING) ................................................... 2-23
11. MT1389MH VIDEO OUTPUT WAVEFORMS ....................................................................................... 2-24
12. DVD & AMP WAVEFORMS MT1389MH .............................................................................................. 2-25
WIRING DIAGRAM ........................................................................................................................................ 2-27
BLOCK DIAGRAMS ...................................................................................................................................... 2-29
CIRCUIT DIAGRAMS .................................................................................................................................... 2-33
1. SMPS CIRCUIT DIAGRAM .................................................................................................................. 2-33
2. MAIN & AMP - 1 CIRCUIT DIAGRAM .................................................................................................. 2-35
3. MAIN & AMP - 2 CIRCUIT DIAGRAM .................................................................................................. 2-37
4. FRONT & POWER KEY CIRCUIT DIAGRAM ...................................................................................... 2-39
5. FRONT JACK CIRCUIT DIAGRAM ...................................................................................................... 2-41
CIRCUIT VOLTAGE CHART ........................................................................................................................ 2-43
PRINTED CIRCUIT BOARD DIAGRAMS .................................................................................................... 2-47
1. MAIN & AMP P.C. BOARD ................................................................................................................... 2-47
2. SMPS P.C. BOARD .............................................................................................................................. 2-51
3. FRONT P.C. BOARD ............................................................................................................................ 2-53
4. POWER KEY P.C. BOARD .................................................................................................................. 2-53
5. FRONT JACK P.C. BOARD .................................................................................................................. 2-53

LG HT306SF Specifications

General

Audio decoders	Dolby Digital
RMS rated power	330 W
Audio output channels	5.1 channels
Weight	3500 g
Audio system	Dolby digital
Built-in HDD	No
Dimensions (WxDxH)	365 x 307 x 58.5 mm
Surround speaker weight	400 g
Apple docking compatibility	Not supported
Surround speaker dimensions (WxHxD)	97 x 110 x 80 mm
Center speaker RMS power	75 W
Satellite speakers RMS power	45 W
Video formats supported	DivX
Radio Data System (RDS)	Yes
Preset stations quantity	50
Disc types supported	CD, CD-R, CD-RW, DVD, DVD+R, DVD+RW, DVD-R, DVD-RW
Optical disc player type	DVD player
HDMI in	0
USB version	2.0
Karaoke	-
Product color	Black

Weight and Dimensions

Subwoofer dimensions (WxDxH)	157 x 325 x 250 mm
Center speaker dimensions (WxDxH)	97 x 80 x 110 mm