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4. TROUBLE SHOOTING
ANTENNA SWITCH MODULE LOGIC
Checking Switch Block power source
LGE Internal Use Only
Copyright © 2007 LG Electronics. Inc. All right reserved.
Only for training and service purposes
Check Soldering of
ANT_SEL0, 1, 2 High Level
2.5V < Voltgae < 3.0V
Check VCC
TP1 VREG_RFRX_0_2.85V
Check the Logic
in each mode
YES
NO
IN_A
IN_B
IN_C
GSM900/GSM850 TX
HIGH
HIGH
LOW
DCS/PCS TX
HIGH
LOW
LOW
GSM 850 RX
LOW
HIGH
LOW
UMTS 850
HIGH
LOW
HIGH
DCS RX
LOW
HIGH
HIGH
PCS RX
LOW
LOW
HIGH
UMTS 1900
HIGH
HIGH
HIGH
GSM900 RX
LOW
LOW
LOW
Logic Table of the Antenna Switch
Summary of Contents for TU550
Page 1: ...Date May 2007 Issue 1 0 Service Manual Model TU550 Service Manual TU550 Internal Use Only ...
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