Only For Training And Service Purposes - LG -P520 Service Manual

3.3.8 Sysclock Switching
The PMU controls the rf_sysclk_en signal of the DCXO in the RF macro. During startup the PMU
enables the DCXO. After the system is running the DCXO is controlled by the SCU of the baseband
by using the vcxo_enable signal. This is handled by a dedicated logic in the PMU, see Figure 3.3.6.
As long as rf_sysclk_en_pmu, the output of the PMU state-machine is high, vcxo_enable controls
the rf_sysclk_en signal to the RF. If rf_sysclk_en_pmu is low, the DXCO is switched off, independent
from vcxo_enable.
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Only for training and service purposes

Figure 3.3.5 PMU, CGU and External Reset
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3. TECHNICAL BRIEF
3. TECHNICAL BRIEF
LGE Internal Use Only