Gsm Mode - LG GM750 Service Manual

3.2. GSM MODE

3.2.1 GSM RECEIVER
The GSM-850, GSM-900, GSM-1800, and GSM-1900 receiver inputs of RTR6285 are connected to
the transceiver front-end circuits(switch module) through saw filters. GSM-850, GSM-900, GSM-1800,
and GSM-1900 receiver inputs use differential configurations to improve common-mode rejection and
second-order non-linearity performance as shown in Figure 1-2. The balance between the
complementary signals is critical and must be maintained from the RF filter outputs all the way into the
IC pins
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[Figure 1-2] GSM Receiver Inputs Topologies
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3. Technical Brief
GM750
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