26Mhz Clock; Power Supplies [Ldo] - LG T5100 Service Manual

2. TECHNICAL BRIEF
Figure 7. Schematic of PAM circuit

2.5 26MHz Clock

The 26MHz clock [X700] consists of a VCTCXO [Voltage Controlled Temperature Compensated
Crystal Oscillator], which oscillates at a frequency of 26 MHz. It is used within the RF Main Chip
[TRF6151, U702], ABB [IOTA, U101], DBB [CALYPSO, U100].
Figure 8. Schematic of VCTCXO circuit

2.6 Power Supplies [LDO]

An external LDO [U704] is used to provide DC power to VCTCXO [X700], Buffer [U703] which is used
for buffering FEM control signals from DBB and the RF Main Chip [TRF6151, U702]
Figure 9. Schematic of LDO circuit
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