LG NP7550 - Section 3 Electrical

3-1
SECTION 3
ELECTRICAL
CONTENTS
ONE POINT REPAIR GUIDE ............................................................................................................................ 3-2
1. NO POWER PROBLEM ......................................................................................................................... 3-2
2. NO SOUND IN PORTABLE MODE ........................................................................................................ 3-3
3. NO SOUND IN BLUETOOTH MODE ..................................................................................................... 3-4
4. NO CHARGING BATTERY ..................................................................................................................... 3-5
ELECTRICAL TROUBLESHOOTING GUIDE ................................................................................................... 3-7
1. POWER/ DSP/ AMP ............................................................................................................................... 3-7
2. CHARGING BATTERY ........................................................................................................................... 3-8
3. AMP ........................................................................................................................................................ 3-9
4. PAIRING BLUETOOTH ........................................................................................................................ 3-10
5. KEY/ LED .............................................................................................................................................. 3-10
WAVEFORMS OF MAJOR CHECK POINT .................................................................................................... 3-11
1. DSP ....................................................................................................................................................... 3-11
2. ADC ....................................................................................................................................................... 3-11
3. BLUETOOTH ........................................................................................................................................ 3-12
4. AMP ...................................................................................................................................................... 3-12
WIRING DIAGRAM .......................................................................................................................................... 3-13
BLOCK DIAGRAMS ........................................................................................................................................ 3-15
1. SYSTEM BLOCK DIAGRAM ................................................................................................................ 3-15
2. POWER BLOCK DIAGRAM ................................................................................................................. 3-17
CIRCUIT DIAGRAMS ...................................................................................................................................... 3-19
1. MAIN - DSP/ ADC/ AMP CIRCUIT DIAGRAM ..................................................................................... 3-19
2. MAIN - POWER/ CHARGER CIRCUIT DIAGRAM ............................................................................... 3-21
3. JACK CIRCUIT DIAGRAM ................................................................................................................... 3-23
CIRCUIT VOLTAGE CHART ........................................................................................................................... 3-25
PRINTED CIRCUIT BOARD DIAGRAMS ....................................................................................................... 3-27
1. MAIN P. C. BOARD .............................................................................................................................. 3-27
2. JACK P. C. BOARD .............................................................................................................................. 3-29