LG KG271 - Page 50

4. TROUBLE SHOOTING
- 51 -
TX Trouble
HB RF Input
LB RF Input
U400
U102
TEST POINT
(50V,J,NP0)
(50V,J,NP0)
(2012)
(16V,K,X7R)
(10V,Z,Y5V) (50V,J,NP0)
(16V,K,X7R)
(50V,J,NP0)
VBAT
C414
27p
VBAT
L402
NA
27p
C407 C408
0.01u
GND7
13 14
GND8
16
GND9
P_GND
21
RSVD_GND
19
20
VAPC
VBATT
17
VCC1A
2
VCC1B
6
1
BS
3
DCS_PCS_INDCS_PCS_OUT
15
EGSM_IN
4
EGSM_OUT
11
18
ENABLE
5
GND1 GND2
7
GND3
8 9
GND4 GND5
10 12
GND6
NA
U400
SKY77318
C416
C405
R407
0
33p
C412
NA
39p
C415
NA
C401
0
R404
C411
NA
C402
10u
R410
0
R408
NA
C409
NA
C404
0.01u
R402 1K
0
R406
R405
0
27p
C413
R409
NA
12p
C403
18p
C406
DCS_PCS_OUT
TXON_PA
BS
GSM_OUT
TX_RAMP
CIRCUIT
Vapc
ASMPaon & BS
Waveform
Check Control
Signals
Signals are
Normal ?
Check
ULC2(U102)
Yes
N
o
PAM Control
Signal is OK.
See next page to
check
ASM & Mobile SW
Circuit.
CHECKING FLOW