Lo Generation And Distribution Circuit - LG -P990 Service Manual

3.5 LO GENERATION and DISTRIBUTION CIRCUIT

3.5 LO GENERATION and DISTRIBUTION CIRCUIT
The PMB 5703 contains two synthesizer blocks (see Figure3-6). Depending on UMTS or GMSK/8-PSK mode
The PMB 5703 contains two synthesizer blocks (see Figure3-6). Depending on UMTS or GMSK/8-PSK mode
different VCOs, LF and CPs settings are used. In GMSK/8-PSK mode only the TRX PLL loop with the 2G TRX VCO is
different VCOs, LF and CPs settings are used. In GMSK/8-PSK mode only the TRX PLL loop with the 2G TRX VCO is
working, which is available in the TX synthesizer block (left). In UMTS TX/RX mode, two separate synthesizer
working, which is available in the TX synthesizer block (left). In UMTS TX/RX mode, two separate synthesizer
blocks are available. The TX synthesizer is in the UMTS TX block (left), where the loop is working with the 3G TX
blocks are available. The TX synthesizer is in the UMTS TX block (left), where the loop is working with the 3G TX
VCO. The RX synthesizer is in UMTS RX block working with the 3G RX VCO.
VCO. The RX synthesizer is in UMTS RX block working with the 3G RX VCO.
LGE Internal Use Only
[Figure 3-6] RF Synthesizer (GMSK/8-PSK and UMTS)
[Figure 3-6] RF Synthesizer (GMSK/8-PSK and UMTS)
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3. TECHNICAL BRIEF
Only for training and service purposes