Off-Chip Rf Components - LG GM750 Service Manual

3. Technical Brief

3.6. OFF-CHIP RF COMPONENTS

3.6.1 ALM-2412(U104:GPS LNA)
The ALM-2412 is an LNA module, with integrated filter, designed for GPS band applications at
1.575GHz. The LNA uses AVAGO Technologies' proprietary GaAs Enhancement-mode pHEMT
process to achieve high gain with very low noise figure and high linearity Noise figure distribution is
very tightly controlled. A CMOS-compatible shutdown pin is included either for turning the LNA on/off,
or for current adjustment. The integrated filter utilizes an Avago Technologies' leading edge FBAR filter
for exceptional rejection at Cell/PCS Band frequencies. The ALM-2412 is useable down to 1V
operation. It achieves low noise figure, high gain and linearity even at 1V, making it suitable for use in
critical low-power GPS applications or during low-battery situations.
1.6.2 SKY77521(U107:FEM + GSM Quad-Band PAM)
SKY77521 is transmit and receive Front End Module(FEM) designed in a very low profile
(1mm), compact form factor for quad-band cellular handsets comprising GSM850/900,
DCS1800, and PCS1900 operation – a complete transmit VCO-to-Antenna and Antenna-to-
receive SAW filter solution. The FEM also supports Class 12 General Packet Radio Service
(GPRS) multi-slot operation and EDGE Polar Modulation. WCDMA switch-through support is provided
by three dedicated high-linearity ports.
LGE Internal Use Only
[Table 1] Antenna Switch Module Logic
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Only for training and service purposes
GM750