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Service Manual
Internal Use Only
Service Manual
U990/KU990
Model : U990/KU990
Date: November, 2007 / Issue 1.0
Table Of Contents
1. INTRODUCTION.................................. 5 4.11 Micro SD trouble ....................................122
1.1 Purpose ...................................................... 5 4.12 Audio trouble..........................................123
1.2 Regulatory Information ............................... 5 4.13 Camera trouble ......................................136
4.14 Main LCD trouble...................................142
2. PERFORMANCE ..................................7 4.15 Bluetooth trouble....................................145
4.16 Bluetooth RF Test..................................146
2.1 System Overview.........................................7
4.17 Touch Screen trouble ............................147
2.2 Usable environment.....................................8
2.3 Radio Performance......................................8
5. DOWNLOAD.....................................148
2.4 Current Consumption.................................16
2.5 RSSI BAR ..................................................17 5.1 Introduction ..............................................148
2.6 Battery BAR ...............................................17 5.2 Downloading Procedure ..........................148
2.7 Sound Pressure Level ...............................18 5.3 Troubleshooting Download Errors ..........161
2.8 Charging ....................................................18 5.4 Caution ....................................................166
3. TECHNICAL BRIEF............................19 6. BLOCK DIAGRAM ...........................167
3.1 General Description ...................................19 6.1 GSM & UMTS RF Block ..........................167
3.2 GSM Mode.................................................21 6.2 Interface Diagram ....................................169
3.3 UMTS Mode...............................................25
3.4 LO generation and distribution circuits ......27
7. CIRCUIT DIAGRAM..........................171
3.5 Off-chip RF Components ...........................27
3.6 Digital Baseband (DBB/MSM6280) ...........37 8. BGA IC PIN MAP..............................183
3.7 Subsystem(MSM6280) ..............................40
3.8 Power Block...............................................48 9. PCB LAYOUT ...................................191
3.9 External memory interface.........................53
3.10 H/W Sub System .....................................55 10. Calibration......................................199
3.11 Feature List..............................................72 10.1 Usage of Hot-Kimchi..............................199
3.12 Multimedia Chip Interface ........................78
3.13 Touch Screen Interface ...........................85 11. EXPLODED VIEW & REPLACEMENT
3.14 Main Features..........................................86 PART LIST ..................................... 203
11.1 EXPLODED VIEW ................................ 203
4. TROUBLE SHOOTING.......................93 11.2 Replacement Parts
4.1 RF Component ..........................................93 ....................... 205
............................... 208
4.2 SIGNAL PATH ...........................................94
11.3 Accessory ............................................. 226
4.3 Checking VCTCXO Block ..........................96
4.4 Checking Front-End Module Block ............98
4.5 Checking UMTS Block.............................101
4.6 Checking GSM Block...............................106
4.7 Power on trouble......................................112
4.8 SIM detect trouble....................................117
4.9 Key sense trouble ( KEYPAD ) ................118
4.10 Keypad backlight trouble .......................120
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