LG KG270, Service Manual

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1. INTRODUCTION ...............................5
1.1 Purpose .................................................. 5
1.2 Regulatory Information............................ 5
2. PERFORMANCE...............................7
2.1 H/W Features...........................................7
2.2 S/W Features ...........................................8
3. TECHNICAL BRIEF ........................14
3.1 Digital Main Processor(PMB7880).........14
3.2 Power Amplifier Module (SKY77318) ....22
3.3 26 MHz Clock (DCXO)...........................24
3.4 RTC(32.768KHz Crystal) .......................25
3.5 LCD Interface(3-wire SPI interface) .......26
3.6 SIM Card Interface.................................28
3.7 KEYPAD Interface .................................29
3.8 Battery Charging Block Interface ...........30
3.9 RF Interface ...........................................31
3.10 Audio Interface.....................................33
3.11 Key LED Interface................................37
3.12 Vibrator Interface .................................38
3.13 Memory Interface .................................39
3.14 Power Block Interface ..........................40
3.15 FM Radio Interface ..............................42
4. TROUBLE SHOOTING ...................44
4.1 RF Trouble .............................................44
4.2 TX Trouble .............................................50
4.3 Power On Trouble..................................54
4.4 SIM Card Trouble...................................56
4.5 Vibrator Trouble .....................................58
4.6 Keypad Trouble......................................60
4.7 RTC Trouble ..........................................62
4.8. Key backlight Trouble ...........................64
4.9. LCD Trouble..........................................66
4.10. Microphone Trouble ............................69
4.11. Receiver Trouble.................................71
4.12 Speaker Trouble ..................................73
4.13 Headphone Trouble .............................75
4.14 Charging Trouble .................................77
4.15 FM Radio Trouble ................................79
5. DOWNLOAD.......................................82
5.1 Download Setup.....................................82
5.2 Download Process .................................83
6. BLOCK DIAGRAM ..........................88
7. Circuit Diagram ..............................89
8. PCB LAYOUT ..................................93
9. ENGINEERING MODE ....................95
9.1 About Engineering Mode .......................95
9.2 Access Codes ........................................95
9.3 Key Operation ........................................95
9.4 Engineering Mode Menu Tree ...............95
10. CALIBRATION ..............................92
10.1 Test Equipment Setup .........................92
10.2 Calibration Steps..................................92
11. STAND ALONE TEST .................109
11.1 Test Program Setting .........................109
11.2 Tx Test ...............................................111
11.3 RX Test ..............................................112
12. EXPLODED VIEW &
REPLACEMENT PART LIST ..... 113
12.1 Exploded View .................................. 113
12.2 Replacement Parts ............................115
12.3 Accessory ......................................... 124
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