Only For Training And Service Purposes - LG GB220 Service Manual

3. TECHNICAL BRIEF
outputs to the four receive pads are connected to the antenna pad through a PHEMT RF switch. The GaAs die,
PHEMT die, Silicon (Si) die and passive components are mounted on a multi-layer laminate substrate. The
assembly is encapsulated with plastic overmold.
Mode
STANDBY
RX1
RX2
RX3
RX4
LB_TX
HB_TX
1. X = DON'T CARE
2. RX1, RX2, RX3, and RX4 are broadband receive ports and each supports the GSM850, GSM900, DCS, and PCS bands.
R402
VLOGIC
R403
TX_RAMP
R405
TX_EN
R406
BS1
R408
BS2
LGE Internal Use Only
LGE Internal Use Only
VLOGIC
0
1
1
1
1
1
1
Figure 3.3.2 Band SW Logic Table
110
1K
110
110
110
C408 C409 C410 C411 C412
1000p 1000p 1000p 39p 1000p
Figure 3.3.3 FEM CIRCUIT DIAGRAM
- 36 -
Input Control Bits
TX_EN BS1
X X
0 0
0 0
0 1
0 1
1 0
1 1
33
PGND3
32
PGND2
31
PGND1
10
U400
GND5
11 SKY77531
RX1
12 SMRH0005201
RX2 DCS_PCS_IN
13
RX3
14
RX4
15
GND6
16
GND7
36
PGND6
35
PGND5
34
PGND4
Copyright © 2009 LG Electronics. Inc. All right reserved. Copyright © 2007 LG Electronics. Inc. All right reserved.

Only for training and service purposes

BS2
X
0
1
1
0
X
X
VBAT
1
GND1
30
VBATT
29
28
GND17
L404
27
GSM_IN
26
2.2nH
GND16
25
GND15
Only for training and service purposes