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Alternate crystal frequency for AD9575

Question asked by tarheel2k on May 26, 2015
Latest reply on May 27, 2015 by pkern

I need to synthesize a 135 MHz very low-phase noise differential (LVDS or LVPECL) clock for my present application.


The AD9575 looks like a convenient choice, though the datasheet indicates that it wants one of three specific reference clocks/crystals as input. From my calculations, in its 6.25 or 6.375 multiplier ratios, it will generate 135 MHz given a 21.6 MHz or 21.17 MHz clock input.


Question: will this work?


Second question: this device is specified for a maximum reference input of 25.78 MHz -- would it tolerate 27 MHz? Used the times 5 mode, this would also meet my requirements.


Advice is appreciated.


[Data Sheet attached for your convenience]