LG KE520 Service Manual page 47

4. TROUBLE SHOOTING
4.1.2 Part Description
4.1.2.1 Regulator
Supply 2.8V to RF part
REGEN
LGE Internal Use Only
U403
VBAT
TPS79928DRVR
6
IN
5
NC
4
C438 EN GND
0.1u PGND
U403
TPS79928DRVR
6
IN
5
NC
4
EN GND
PGND
U404
<Fig.1> Regulator Circuit Diagram
- 48 -
U404
VCC_SYN
U403
1
OUT
2
NR
3
7
C439 C440
0.01u 2.2u
C441
NA
C_VCCRF
U404
1
OUT
2
NR
3
7
C442 C443
0.01u 2.2u
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