Gsm Mode - LG CT815 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
directly to the transceiver front-end circuits(filters and antenna switch module). GSM-850, GSM-900,
GSM-1800, and GSM-1900 receiver inputs use differential configurations to improve common-mode
rejection and second-order nonlinearity performance as shown in Figure 3-2. 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 3-2] GSM Receiver Inputs Topologies
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3. TECHNICAL BRIEF
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