ZL50015 ZARLINK [Zarlink Semiconductor Inc], ZL50015 Datasheet - Page 40

• Manufacturer Part Number: ZL50015
• Description: Enhanced 1 K Digital Switch with Stratum 4E DPLL
• Manufacturer: ZARLINK [Zarlink Semiconductor Inc]

12.1.3.2
If a particular reference needs to have higher priority than the others, the device can be programmed in Automatic
mode with a preferred reference (RCCR Register, PMS2-0 bits = 001). When a preferred reference is selected, the
device can only switch automatically between two references, as shown in Table 8. The preferred reference will be
used as the primary reference and, by default, only its next consecutive reference will be used as the secondary
reference. No more than two references can be used in Automatic mode when a preferred reference is selected.
Figure 22 shows the state diagram for the four valid options of automatic reference switching with a preferred
reference.
Option 1
Option 2
Option 3
Option 4
Automatic Reference Switching With Preferences
Table 8 - Preferred Reference Selection Options
Primary Reference (Preferred)
Ref 0
Ref 1
Ref 2
Ref 3
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ZL50015
40
Secondary Reference
Ref 1
Ref 2
Ref 3
Ref 0
Data Sheet