1. INTRODUCTION ... 5 1.1 Purpose... 5 1.2 Regulatory Information... 5 2. PERFORMANCE...7 2.1 System Overview ...7 2.2 Usable environment ...8 2.3 Radio Performance ...8 2.4 Current Consumption...14 2.5 RSSI BAR ...14 2.6 Battery BAR ...14 2.7 Sound Pressure Level...15 2.8 Charging ...16 3. TECHNICAL BRIEF ...17 3.1 General Description ...17 3.2 GSM Mode...20 3.3 WCDMA Mode...23 3.4 LO Phase-locked Loop ...26 3.5 Off-chip RF Components ...28 3.6 Digital Baseband(DBB/MSM6250A) ...35 3.7 Hardware Architecture ...36 3.8. Subsystem(MSM6250A)...38 3.9. External memory interface ...41 3.10. H/W Sub System...42 3.11 LG U310 Main features...66 4. TROUBLE SHOOTING ...72 4.1 RF Component...72 4.2 SIGNAL PATH ...73 4.3 Checking VCTCXO Block ...75 4.4 Checking Ant. SW Module Block ...78 4.5 Checking WCDMA Block ...81 4.6 Checking GSM Block ...87 4.7 Bluetooth RF Block ...95 4.8 Power ON Trouble ...97 4.9 USB Trouble ...99 4.10 SIM Detect Trouble ...100 4.11 Key Sense Trouble ...101 4.12 Camera Trouble ...102 4.13 Main LCD Trouble...103 4.14 Folder ON/OFF Trouble ...105 4.15 Camera Direction Detection Trouble..106 4.16 Trans Flash Trouble...107 4.17 Audio Trouble Shooting ...108 4.18 Charger Trouble Shooting...118 5. DOWNLOAD ...121 5.1 Introduction ...121 5.2 Downloading Procedure...121 5.3 Troubleshooting Download Errors ...135 5.4 Caution...140 6. BLOCK DIAGRAM...141 6.1 GSM & WCDMA RF Block...141 6.2 Interface Diagram ...142 7. Circuit Diagram ...143 8. pcb layout ...150 9. Calibration & RF Auto Test Program ...155 9.1 Configuration of HOT KIMCHI ...155 9.2 How to use HOT KIMCHI...159 9.3 Example for using HOT KIMCHI ...160 10. EXPLODED VIEW & REPLACEMENT PART LIST ... 163 10.1 EXPLODED VIEW ... 163 10.2 Replacement Parts ... 165

... 169 10.3 Accessory ... 187