Topic: VCO frequency other than the default 2456.7MHz  (Read 3152 times)

stanstanev June 24, 2013, 11:12 PM

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Hi,

Have you been able to configure the board with a lower frequency (approx 2GHz) by setting the clocktree dividers such that the PLL locks?  The documentation refers to a limitation due to the external loop filter components and mentions "other configurations should be investigated case by case". I have tried a few different divider settings for the VCO but the PLL does not lock.
Any suggestions would be very appreciated.

Thanks
Stan

arnaudNL June 25, 2013, 04:01 AM (#1)

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Dear Stan,


I guess this indicates that loop filter might be narrow range and might need to be changed for a given frequency.


I think you should discuss that with sales, they should be able to provide you with more information or maybe even a characterized solution.


Best Regards,
Arnaud

stanstanev June 25, 2013, 08:08 PM (#2)

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Hi Arnaud,

I should have looked closer at the datasheet. The clock distribution device (AD9517-1) on the FMC230 has a VCO range of 2.3 to 2.65GHz.  AD9517-2 supports VCO range down to 2GHz.  Is there a version of FMC230 that has a -2 installed? perhaps that is a question for sales?
Thanks
Stan

arnaudNL June 26, 2013, 04:36 AM (#3)

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Hello Stan,


I guess there should be a custom ordering option to cover that, or maybe a custom option should be created for this. I think we should be able to get a specific AD9517 device but yeah, sales engineers are able to provide you a more accurate information.


You can contact sales@4dsp.com for more information, Michael is a very competent sales engineer!


Best Regards,
Arnaud