LG C2100, Service Manual

Page: 2 / 135

- 3 -
1. INTRODUCTION .............................. 5
1.1 Purpose................................................... 5
1.2 Regulatory Information............................ 5
1.3 Abbreviations .......................................... 7
2. PERFORMANCE.............................. 9
2.1 H/W Features.......................................... 9
2.2 Technical Specification ......................... 10
3. TECHNICAL BRIEF ....................... 15
3.1 Transceiver (SI4205, U505).................. 15
3.2 Power Amplifier Module
(SKY77325, U501)................................ 21
3.3 26 MHz Clock (VCTCXO, X500)........... 22
3.4 Power Supplies for RF Circuits
(RF LDO, U503).................................... 22
3.5 Digital Main Processor
(AD6527, U101) .................................... 23
3.6 Analog Main & Power Management
Processor (AD6537B, U102) ................ 29
3.7 Display and Interface ............................ 39
3.8 Keypad Switches and Scanning ........... 41
3.9 Microphone ........................................... 42
3.10 Main Speaker...................................... 42
3.11 Headset Interface................................ 43
3.12 Key Back-light Illumination.................. 44
3.13 LCD Back-light Illumination................. 45
3.14 VIBRATOR.......................................... 46
4. TROUBLESHOOTING ................... 47
4.1 RX Trouble............................................ 47
4.2 TX Trouble ............................................ 55
4.3 Power On Trouble................................. 63
4.4 Charging Trouble .................................. 65
4.5 Vibrator Trouble .................................... 67
4.6 LCD Trouble.......................................... 69
4.7 MIC Trouble .......................................... 71
4.8 SIM Card Interface Trouble................... 73
4.9 Earphone Trouble ................................. 75
4.10 KEY backlight Trouble ........................ 77
4.11 Receiver Trouble................................. 79
4.12 Microphone Trouble ............................ 81
4.13 RTC Trouble ....................................... 83
4.14 Indication LED Trouble ....................... 85
4.15 Folder on/off Trouble........................... 87
5. DOWNLOAD AND
CALIBRATION ............................... 89
5.1 Download .............................................. 89
5.2 Calibration............................................. 95
6. BLOCK DIAGRAM ......................... 98
7. CIRCUIT DIAGRAM ....................... 99
8. PCB LAYOUT ............................... 105
9. ENGINEERING MODE ................. 107
9.1 BB Test [MENU 1]............................... 108
9.2 RF Test [MENU 2]............................... 109
9.3 MF mode [MENU 3] ............................ 110
9.4 Trace option [MENU 4] ....................... 111
9.5 Call timer [MENU 5] ............................ 111
9.6 Fact. Reset [MENU 6] ......................... 111
9.7 S/W version......................................... 111
10. STAND ALONE TEST ................ 112
10.1 Introduction ....................................... 112
10.2 Setting Method.................................. 112
10.3 Means of Test ................................... 113
11. AUTO CALIBRATION................. 115
11.1 Overview ........................................... 115
Table Of Contents