4. TROUBLE SHOOTING
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4. BB Trouble Shooting
4.11 USB Troubleshooting
USB Initial sequence of U250/KU250 is :
USB connected to U250/KU250 power on
→
USB_VBUS(Q300) go to 5V
→
USB_D+ go to 3.3V
→
USB_DAT is triggered
→
USB work.
Start
Q400 pin 4 is 5V?
USB_D+ is 3.3V?
Change the Main board
Check Q300 (pin 4)
Check VA401
NO
YES
YES
NO
Cable is inserted?
YES
Insert cable
NO
Power is on?
YES
Go to power on trouble shooting
NO
Содержание U250
Страница 1: ...Date June 2007 Issue 1 0 Service Manual Model U250 KU250 Service Manual U250 KU250 ...
Страница 3: ... 4 ...
Страница 20: ...3 TECHNICAL BRIEF 21 Fig 1 2 RTR6275 RX feature ...
Страница 23: ...3 TECHNICAL BRIEF 24 Figure 1 4 RTR6275 IC functional block diagram WCDMA_2100_TX WCDMA_2100_RX ...
Страница 28: ...3 TECHNICAL BRIEF 29 Figure1 7 PM6650 Block Diagram ...
Страница 41: ...3 TECHNICAL BRIEF 42 Table 1 2 Description of RF configurations ...
Страница 45: ...3 TECHNICAL BRIEF 46 Figure 1 12 PM6650 Functional Block Diagram ...
Страница 72: ...4 TROUBLE SHOOTING 73 4 1 RF Component 4 TROUBLE SHOOTING LGMC ...
Страница 73: ...4 TROUBLE SHOOTING 74 Block Diagram Block Ref Name UMTS Part Name Function Comment ...
Страница 77: ...4 TROUBLE SHOOTING 78 Check C312 of PMIC U300 Check R213 of MSM U201 T ...
Страница 81: ...4 TROUBLE SHOOTING 82 ...
Страница 84: ...4 TROUBLE SHOOTING 85 ...
Страница 85: ...4 TROUBLE SHOOTING 86 4 7 Checking GSM Block 1 3 2 ...
Страница 87: ...4 7 3 Checking RF Tx level 4 TROUBLE SHOOTING 88 ...
Страница 90: ...4 TROUBLE SHOOTING 91 ...
Страница 97: ...4 TROUBLE SHOOTING 98 R313 Q301 Q302 Q300 Charging part Main PCB Front ...
Страница 107: ...4 TROUBLE SHOOTING 108 R422 R421 U401 ...
Страница 109: ...4 TROUBLE SHOOTING 110 C401 C402 R406 C407 CN401 ...
Страница 111: ...4 TROUBLE SHOOTING 112 Analog Switch Audio Amp SPK ...
Страница 113: ...4 TROUBLE SHOOTING 114 MIC400 C417 R424 ...
Страница 115: ...4 TROUBLE SHOOTING 116 Ear_Sense_N MIC Input ...
Страница 117: ...4 TROUBLE SHOOTING 118 VPWR MOTOR_PWR ...
Страница 133: ...6 BLOCK DIAGRAM 134 6 1 GSM UMTS RF Block 6 BLOCK DIAGRAM Fig 2 1 U250 KU250 RF Functional Block Diagram ...
Страница 134: ...6 BLOCK DIAGRAM 135 Table 2 1 RF Block Component ...
Страница 136: ...6 BLOCK DIAGRAM 137 6 2 2 Memory Interface Fig 2 3 Memory Interface Diagram ADDRESS 14 0 ...
Страница 137: ...6 BLOCK DIAGRAM 138 6 2 3 USB UART SIM JTAG Interface Fig 2 4 USB UART SIM JTAG Interface ...
Страница 139: ...6 BLOCK DIAGRAM 140 6 2 4 Placement Top Side LGMC ...
Страница 140: ...6 BLOCK DIAGRAM 141 Bottom Side LGMC ...
Страница 141: ... 142 ...
Страница 146: ... 147 LGMC 8 PCB LAYOUT U250 KU250 ...
Страница 147: ... 148 LGMC 8 PCB LAYOUT U250 KU250 ...
Страница 157: ... 158 ...
Страница 174: ...Note ...
Страница 175: ...Note ...