CDCM7005: Can This Part Synchronize to 1PPS

gchampin

Part Number: CDCM7005
Other Parts Discussed in Thread: LMK05028

Hello,

I am trying to develop a solution that will take a 10 MHz signal from a OCXO and synchronize it to a 1PPS signal from GPS. Afterwards, I would like to synthesize frequencies that can be non-integer from this synchronized 10 MHz. Is there a combination of solutions that could accomplish this? I tagged the CDCM7005 because it said it could take reference frequencies as low as 0 MHz so perhaps this could synchronize the 10 MHz with the 1PPS and then I could synthesize with a different chip?

Thanks for any help!

Best,

gchampin

over 7 years ago

0 Alan O over 7 years ago

TI__Mastermind 32575 points

Hello,

I would not recommend the CDCM7005 to lock to 1 PPS input as this requires a very narrow loop bandwidth (<50 mHz) which is difficult to achieve with traditional analog PLL (PFD/CP-based), external VCXO, and external loop filter. We have a clock device in development that is releasing soon that could support 1 PPS lock using a 10 MHz OCXO as a holdover/backup reference and generate multiple non-integer-related clocks frequencies. Please send an email to clock_support@list.ti.com with some details on your contact name/info, company name, and end-equipment, so can share some information on the upcoming clock device.

Regards,
Alan

0 Shawn Han over 7 years ago

TI__Genius 9920 points

Hi gchampin,

CDCM7005 can't lock 10 MHz from 1PPS. The divider in CDCM7005 is not enough.
For your application, DPLL solution would be better. TI would release DPLL LMK05028 around end of March.
You would find it on website after it released.

If you would like to learn more about LMK05028 earlier, please send your request with your company and project info to clock_support@list.ti.com
Thanks.

Regards,
Shawn

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CDCM7005: Can This Part Synchronize to 1PPS