Control Flow - LG GU280 Service Manual

3. Technical Brief

3.5. Control Flow

The access side of the digital baseband controller controls the overall radio system. In both EDGE/GSM/GPRS
and W-CDMA air interface mode, the digital baseband controller controls the radio system through a serial bus.
The digital baseband controller also manages PA band control and the antenna switch mechanism in the front end
module. The 26 MHz VCXO clock residing in the GSM/EDGE transceiver is turned on only when required, the digital
baseband controller initiates this.
The EDGE/GSM/GPRS RF system requires control, which is temperature dependent.
The temperature within the RF system is estimated by a voltage measurement performed by the analog baseband
controller. The control flow for the RF system is shown in Figure 1.5.1.
LGE Internal Use Only
Figure 1.5.1 Block diagram of FEM
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