Only For Training And Service Purposes - LG KG270 Service Manual

TX Trouble
TEST POINT
U400
HB RF Input
Waveform
Paon & BS ASM
Copyright © 2007 LG Electronics. Inc. All right reserved.

Only for training and service purposes

C403 C404
12p 0.01u
LB RF Input
U102
Vapc
- 51 -
4. TROUBLE SHOOTING
CIRCUIT
VBAT
C402
C405 C406
10u
33p 18p
(2012)
(50V,J,NP0)
15 3
DCS_PCS_OUT DCS_PCS_IN
R406
11 4
U400
EGSM_OUT EGSM_IN
SKY77318
0
19 18
C411 C412 RSVD_GND ENABLE
NA NA
21 1
P_GND BS
R410
0
C416
C415
NA NA
CHECKING FLOW
Check Control
Signals
Signals are
Normal ?
Yes
PAM Control
Signal is OK.
See next page to
check
ASM & Mobile SW
Circuit.
VBAT
R404 R405
0 0
L402
NA
C407 C408
27p 0.01u
C409
NA
(16V,K,X7R)
R407
0
TXON_PA R409
R408
NA NA
BS
C413 C414
27p 27p
N
Check
o
ULC2(U102)
LGE Internal Use Only
DCS_PCS_OUT
GSM_OUT