Checking Wcdma Block - LG U830 KU830 Service Manual

4.5 Checking WCDMA Block

4.5.1 Checking TX POWER of WCDMA 2100MHz
Antenna
0.75p
L503
WCDMA PAM
U504
SMPY0012701
PGND
17
RF_OUT
11
VCC2B
9
VCC2A
13
TP3
C570 C571
0.01u 0.01u
C581
Coupler
100p
IN COUP
2 3
OUT 50OHM
1 4
L531
NA
G1
G2
ANT G3
Duplexer
G4
G5
G6
G7
TP2
5p
SW500
R500
R501
G2
ANT
G1
3.3nH
KMS-512
RF Mobile
15nH
C501
Switch
+VPWR
VREF
5
RF_IN
3
VENABLE
2
270
R523
PA_R1
VMODE
1
C562
0.01u
+VPWR
C565
10u
Q2_E
C576 C577
4
100p 0.01u
Q2_B
5
Q1_C
6
R526
68
ADL5500 U507
VOPS VRMS HDET1
RFIN COMM C585
0.01u
HDET
L534 2.2nH
27p
C589
- 83 -
4. TROUBLE SHOOTING
TP1
C500
RF
L502
NA
TP4
C563
0.01u
VREG_RFRX_0_2.85V
Q2_C
3
Q1_B
PA_ON
2
Q1_E
1
Q500
VREG_RFTX_2.85V
ILNA_OUT
L535 3.3nH
C591
1.2p
TP1: RF Mobile Connector Output
TP2: Duplexer Output
TP3: WCDMA PAM Output
TP4: WCDMA PAM Input
33p
FL501
EFCH1950TDC1 3
G3
4 1
OUT IN
G2 G1
L
5 2
0.5p
C558
C574 C575
0.1u 100p
C582 C583
0.1u 100p
13
PLNA_OUT
14
ILNA_OUT
15
PLNA_BIAS
16
PLNA_IN
17
ILNA_BIAS
18
ILNA_IN
19
RF
VDDRF3
20
RX_IP
21
RX_IM
22
RX_QP
23
RX_QM
24
VDDA2
RX_QM
RX_QP
RX_IM
RX_IP