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Flow Chart of Troubleshooting
5-21
5-12 GSM Transmitter
Tx On (level : 5)
U304
Pin 2
≥
30 dBm
U304
Pin 7
≥
30 dBm
U318
Pin 1
≥
30 dBm
U312
Pin 1
≥
-10 dBm
OSC301
Pin 1
≥
-10 dBm
OSC301
Pin 6
≤
0.5 V
Pin 10
≥
2.8 V
Pin 7
≥
2.8 V
Pin 9 = 0.5~2.5 V
Resolder
J301
Check
VC1 : H
VC2 : L
VC3 : L
Change or Resolder
U304
Resolder
U318, C353
Resolder or Change
R334, R335, R364, R366
Resolder
OSC301, R343
U305
pin 30, 47
≥
-10 dBm
Resolder
U305, U302
U305
Pin 17, 18, 19, 20
≥
40 mV
Resolder
OneC(U108)
Check U305
Pin 38
≥
2.5 V
Pin 35
≤
0.5 V
Resolder
U305 (Pin35, Pin38)
Resolder
U108
No
No
No
No
No
No
No
No
No
No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Check
Ant. S/W Control Circuit
Check
U312 : +VBATT,
Pin 2 (APC)
OK?
Resolder or
Change U312
Yes
Check +VBATT
or APC Control
No
Summary of Contents for SGH-N300
Page 2: ...Samsung Electronics Co Ltd Printed in Korea 06 2001 Rev 1 0 GH68 02097A ELECTRONICS ...
Page 11: ...Exploded Views and Parts List 1 8 1 10 Desk Top Charger DESK TOP CHARGER GH44 00206A ...
Page 12: ...2 1 PCB Diagrams Schematic Diagrams 2 PCB Diagrams 2 1 Main Top ...
Page 13: ...2 2 PCB Diagrams Schematic Diagrams 2 2 Main Bottom ...
Page 41: ...Flow Chart of Troubleshooting 5 12 J101 SPK101 U110 PWO1P PWO1N SPK SPK 6 2 3 SPK SPK ...