LG MG180C Service Manual page 77

4. TROUBLE SHOOTING
4.15.1 Checking Regulator Circuit (Tx pass continued)
Check P in 5
2.85V ?
No
Pin 3 H igh ?
No
Check U1 00
PIN3
Regulat or circuit is OK .
Yes
See next page to check
VCTCXO circuit
Yes
Repl ace U502
PIN5
VBAT
RF_EN
C533 C534
1000p 4.7u
- 76 -
RF2.85V
U502
1 5
VDD VOUT
2
GND
3 4
CE NC
R1114N281D-TR-F
C535 C536 C537
NA 4.7u 1u
PIN5
PIN3