45
12. When Rx sensitivity isn't good enough
Checking Flow
- U1303 : MAX1827(PMIC)
- X1100 : TG-5000(TCXO)
- U1107 : CP0603A08368NTR(Coupler)
- U1101 : YGHF-D010A ( RF module)
- U1201 : MSM6100
Check Rearcase ANT
contact OK ?
Check U1303 pin12 2.6V,
pin17 3V, pin19 3V
Check X1100 pin3 19.2MHz
Check RF signal
at L1105 882MHz
Change U1101
-Rx Test setup
1.Mode offline-d
2.CH “400”
-E5515C(8924C) setting
1.CH “400”
2.Sector Power : -30 dBm
Check ANT contact
remove dust
Check circuit around, &
change U1303
NO
NO
Change X1100
NO
NO
Yes
Yes
Yes
Yes
Done
Check U1201(MSM6100)
Check U1107
NG
OK
(High Frequency Probe using measure)
Z3X-BOX.COM
Summary of Contents for LG-UD90c
Page 1: ...CDMA PORTABLE CELLULAR PHONE LG UD90c SERVICE MANUAL Z 3 X B O X C O M ...
Page 23: ...LG KG90C 23 Waveform TCXO TCXO_OUTPUT X1100 Z 3 X B O X C O M ...
Page 27: ...LG KG90C 27 Test Point Circuit Diagram CON3100 X3100 X3100 pin3 Z 3 X B O X C O M ...
Page 29: ...LG KG90C 29 Test Point Circuit Diagram Mic R211 Mic bias resistor MSM6100 Z 3 X B O X C O M ...
Page 30: ...LG KG90C 30 5 When Receiver Earpiece isn t heard Checking Flow Z 3 X B O X C O M ...
Page 31: ...LG KG90C 31 Test Point Circuit Diagram R3000 R3001 U1409 Z 3 X B O X C O M ...
Page 33: ...LG KG90C 33 Test Point Circuit Diagram MOTOR_EN TP3001 Motor pad Z 3 X B O X C O M ...
Page 35: ...LG KG90C 35 Test Point Circuit Diagram U2001 Z 3 X B O X C O M ...
Page 37: ...LG KG90C 37 Test Point Circuit Diagram CON2000 Z 3 X B O X C O M ...
Page 39: ...LG KG90C 39 Test Point Circuit Diagram Blue Tooth ANT U2000 Z 3 X B O X C O M ...
Page 41: ...LG KG90C 41 Test Point Circuit Diagram U1409 U1403 CON 1401 U1401 Z 3 X B O X C O M ...
Page 42: ...LG KG90C 42 11 When Tx power isn t good enough Checking Flow Test Point Z 3 X B O X C O M ...
Page 43: ...LG KG90C 43 Circuit Diagram U1107 U1106 X1100 U1101 Z 3 X B O X C O M ...
Page 44: ...LG KG90C 44 Waveform Z 3 X B O X C O M ...
Page 46: ...LG KG90C 46 Test Point Circuit Diagram U1107 U1101 X1100 Z 3 X B O X C O M ...
Page 67: ...Z 3 X B O X C O M ...
Page 68: ...Z 3 X B O X C O M R1335 R1336 47K 10k변경 5 1 일 R1356 R1357 DNI 560k R1317 DNI 200K 변경 5 1일 ...
Page 70: ...Z 3 X B O X C O M C1510 100n 0 1uF 변경 5 1일 ...
Page 71: ...Z 3 X B O X C O M ...
Page 72: ...Z 3 X B O X C O M ...
Page 73: ...Z 3 X B O X C O M C2010 10n 6 8n 5 1일 변경 ...
Page 74: ...Z 3 X B O X C O M ...
Page 77: ...Z 3 X B O X C O M U3100 Charge pump Not LCD backlight on ...
Page 79: ...Z 3 X B O X C O M M2001 Microphone MIC not work ...
Page 81: ...Z 3 X B O X C O M U4009 Touch sensor Touch key not work ...
Page 82: ...Z 3 X B O X C O M ...