Only For Training And Service Purposes - LG TU750 Service Manual

3.7.5. 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 three-wire 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 3-7-11.
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Only for training and service purposes

Figure 3-7-11. RF Control Flow
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3. TECHNICAL BRIEF
LGE Internal Use Only