Front End Module Control; Power Amplifi Er Module - LG KC560 Service Manual

3. TECHNICAL BRIEF

3.23. Front End Module control

Implemented in the S-Gold3 (FL400) are three outputs which are FE1, FE2 for direct control of front end
modules with two logic input pins to select RX and TX mode as well as low and high band operation.
Table 11 FEM Control Logic
GSM850/900 TX
DCS/PCS TX
GSM850/900 RX
DCS/PCS RX
UFL-R-SMT10
2
G1
3
G2 ANT
CN401
3.24. Power Amplifier Module
The The TQM7M5005 is an extremely small (5x5x1.1mm3) multi-mode power amplifier module for
GSM/EDGE applications. This module has been optimized for high EDGE efficiency and EDGE power
class E2 operation while maintaining high GSM/GPRS efficiency. In EDGE mode, the Vramp pin
provides a continuously variable bias control to minimize current consumption during backed-off power
conditions. The module incorporates two highly integrated InGaP power amplifier die with a CMOS
controller. The CMOS controller implements a fully integrated closed-loop power control within the
module for GSM Operation. This eliminates the need for any external couplers, power detectors, current
sensing etc., to assure the output power level. The latter is set directly from the Vramp input from the
DAC. The module has Tx enable, band select, mode (EDGE or GSM) inputs. Module construction is a
low-profile over-molded land-grid array on laminate.
LGE Internal Use Only
VDD VC1(FE1)
H L
H H
H L
H H
LS Cable
C407
22p
SW400
G2
ANT RF
G1
GRS301-2S-H26-E3000
Figure 33 FEM schematic
- 54 -
VC2(FE2)
H
H
L
L
2V85_VRF
C400 C401
C404
0.1u 100p
39p
FL400
DGM1110M014
ANT
17 D5008( E pcos)
Copyright © 2008 LG Electronics. Inc. All right reserved.
Only for training and service purposes
FE1
FE2
C448
100p
C463
100p