Power Supplies And Control Signals - LG CG225 Service Manual

3.3.3. Power Supplies and Control Signals

An external regulator(U503) is used to provide DC power to RF part. Every RF component except
power amp module uses this external regulator.
RF_EN
VBAT
U503
1
VDD VOUT
2
GND
3
CE NC
R1114N281D-TR-F
C560 C532
1000p 4.7u
Figure 6 External regulator Circuit
- 19 -
3. H/W Circuit Description
RF2.85V
5
4
C533 C534 C535
NA 10u 1u