LMX2571: LMX2571 VCO and BUF

Eric Shen42

Expert 2750 points

Part Number: LMX2571

Dear TI team:
1, Can customer shut down the internal VCO of LMX2571 and how to shut down?

2, Customer used BUF of LMX2571, they found spurious, what can the customer make for the spurious?

Thanks!

0 Shawn Han over 5 years ago

1, The LMX2571 supports an external VCO in PLL mode. In PLL mode, the internal VCO and its associated charge
pump are powered down.

R24.5
EXTVCO_SEL_F2
Selects synthesizer mode (internal VCO) or PLL mode (external VCO) operation.
0 = Synthesizer mode
1 = PLL mode

2, If output from LMX2571 and VCO are good, try to check power supply noise on buffer.

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