4.7 ANALOG LOCK DETECT FILTER

When the Fo/LD output is configured in analog lock detect mode an external lock detect circuit is needed in order to provide a

steady LOW signal when the PLL is in the locked state. A typical circuit is shown below. The fold output is active low (open drain)

only when analog lock detect mode is selected.

4.8 TYPICAL LOCK DETECT TIMING

DS100831-5

DS100831-6

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