LG KT520 Service Manual page 125

4. TROUBLE SHOOTING
4.15.4 Checking VCC
R603 (VDIGRAD_1V8)
Main Board (Bottom side) : Power for Radio ASIC
C601 C602
1u 1u
C12
VDD_A
B11
EXTLDO
F12
VDD_D
D12
VDD_E
AB3000
Check Point
VRADA_2V8
(R602)
Check Point
VDIGRAD_1V8
(R603)
LGE Internal Use Only
AB3000
0
R602
VRADA_2V8 (RF3000, RF3100 analog, Power Detector)
R639 0
0
R603
C603
2.2u
Schematic (Power)
2.8V OK?
1.8V OK?
Common Input Power is OK
See The Next Part
- 126 -
R602 (VRADA_2V8)
VRADA_2V8
VDDD_1V5
VDDE_1V8
VDDC_2V65
VDIGRAD_1V8 (RF3000, RF3100 digital)
VDDH_CAM_CORE
VDDF_2V5
TP06_RF
C503 (VDD_E)
Check the AB3000
No
Yes
Check the AB3000
No
Yes
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
VBAT
VDIGRAD_1V8
VBAT
VRADA_2V8
VDDD_1V5
VDDE_1V8
VDIGRAD_1V8
VDDG_2V75
VDDK_2V75
VDDC_2V65