LG C1150 Service Manual page 50

(1) Checking Regulator Circuit
Test Points
Circuit Diagram
Checking Flow
Check Pin 5.
Regulator Circuit is OK
See next Page to check
VCTCXO
U303. 5
Figure 4-2
VRF
MIC5255-2.85BM5
5
OUT
C343
4
C344 BYP
0.01u
10u
RF 2.85V O.K?
No
Yes
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4. TROUBLE SHOOTING
U303. 3
VBAT
U303
1
IN
2
GND
3
EN CLKON
C345
4.7u
No
Pin 3. High ?
Yes
Replace U303
Changing the Board