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WEBENCH® Tools/LMK04610: When will simulation tools be available?

Jeff Philips28
Prodigy 140 points
Part Number: LMK04610
Other Parts Discussed in Thread: LMX2581, LMX2572, LMX2582

Tool/software: WEBENCH® Design Tools

Dear TI,

I'm unable to model phase noise, jitter, or spurs for the LMK04610 with any of your simulation tools?  For example, Webench returns a message along the lines that "Simulation is not yet enabled for this part."  When will I be able to simulate the LMK04610?

I'm using the LMK04610 to create a 10MHz clock reference for your LMX2581 and a 200MHz sample clock with less than 100fs RMS jitter.  I need a better idea of what frequency should be used for the LMK04610's reference input and what frequency should be used for the VCXO.

Any interim suggestions?

Thank you,

Jeff

  • 0
    TI__Guru** 110810 points
    Hi Jeff,

    I will have my colleague answered your question on simulation tool.
    For the application question, I suggest a higher reference clock frequency than 10MHz. A higher reference means a higher fpd is possible which is in favor to a fractional-N PLL, close-in noise could be smaller.
    I suggest a 100MHz VCXO for LMK04610 PLL1. LMX2581's reference clock is also taken from PLL1.
    PLL2 is used to generate the 200MHz sample clock.
  • 0 in reply to Noel Fung
    Prodigy 140 points

    Hi Noel,

    Thanks for your help.

    I haven't heard anything from your coworker about when I'll be able to simulate jitter in the LMK04610 using any of the usual simulation tools.

    From the LMX2581, I need a 2290MHz tone that must be provided in integer-N mode; the fractional-N spurs are way too high.  That's why I need the 10MHz reference from the LMK04610.

    I also need 100 and 200MHz clocks from the LMK04610.  Will I be able to obtain less than 100fs RMS jitter on the 200MHz clock, which is the sample clock for an ADC?

    For those 10, 100, and 200MHz outputs from the LMK04610, is 100MHz suitable for its reference input and VCXO frequency?

    Thanks, Jeff

  • 0 in reply to Jeff Philips28
    TI__Mastermind 28021 points
    Jeff,

    Unfortunately, we do not have plans to upgrade simulations for the LMK04610.

    The LMK04610 has a semi-digital approach to the loop filter which makes the modeling of this incompatible with our tools (Clock Architect and PLLatinum Sim). Therefore, there is no plan to update these tools to support LMK04610 simulations.

    That being said, the TICSPro program supports the LMK04610 and has a a tool built into this for the loop filter so the user. This is all that we have to offer for the LMK04610 in regards to simulation and loop filter design.

    Regards,
    Dean
  • 0 in reply to Dean Banerjee
    TI__Guru** 110810 points
    Hi Jeff,

    As for the synthesizer, consider to use LMX2582 or LMX2572, their spurs is better than LMX2581. If possible, I still recommend to use a higher fpd.