zl50019gag2 Zarlink Semiconductor, zl50019gag2 Datasheet - Page 39

• Manufacturer Part Number: zl50019gag2
• Description: Enhanced 2 K Digital Switch With Stratum 4e Dpll
• Manufacturer: Zarlink Semiconductor

12.1.3.1
When the DPLL is programmed to operate in Automatic mode without Preference (RCCR Register, PMS2-0 bits =
000), all references, REF0-3, will have equal importance. A circulating Round Robin selection sequence
determines the reference to be used as shown in Figure 21. The state machine basically searches for valid
reference in a circular order of REF0 -> REF1 -> REF2 -> REF3 -> REF0, etc.
Ref 0
Figure 21 - Automatic Reference Switching State Diagram with No Preferred Reference
Automatic Reference Switching Without Preferences
Ref 0 valid
Ref 0 failed
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Free run
Ref 3
Start
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Zarlink Semiconductor Inc.
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ZL50019
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Holdover 1
Holdover 2
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Data Sheet
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