ds3102 Maxim Integrated Products, Inc., ds3102 Datasheet - Page 10

• Manufacturer Part Number: ds3102
• Description: Stratum 3 Timing Card Ic With Synchronous Ethernet Support
• Manufacturer: Maxim Integrated Products, Inc.

____________________________________________________________________________________________ DS3102
The entire chip is clocked from the external oscillator connected to the REFCLK pin. Thus, the free-run and
holdover stability of the DS3102-based timing card is entirely a function of the stability of the external oscillator, the
performance of which can be selected to match the application: TCXO, OCXO, double-oven OCXO, etc. The
12.8MHz clock from the external oscillator is multiplied by 16 by the Master Clock Generator block to create the
204.8MHz master clock used by the rest of the device. Since every block on the device depends on the master
clock and therefore the local oscillator clock for proper operation, the master clock generator has a watchdog timer
(WDT) function that can be used to signal a local microprocessor in the event of a local oscillator clock failure.
The DS3102 also has several features to support master/slave timing card redundancy and protection. Two
DS3102 devices on redundant cards can be configured to maintain the same priority tables, choose the same input
references, and generate output clocks and frame syncs with the same frequency and phase.
Rev: 012108
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