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minkyo's avatar
minkyo
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5 years ago

ALTPLL ouput clock doesn't synchronize.

Hi

I'm using cyclone 10 lp which is 10CL120YF484I7G on my own board.

My problem is when I made clock using alt pll, the clock's phasee didn't matches.

Actually, I'm using 2 alt pll to make some clocks. is it problem?

why the clocks does not synchronize?

I set normal mode in alt pll and others are default.

Input clock is 32Mhz, outputs 12.288Mhz, 3.072Mhz, 48KHz.

I attached a capture which is part of clocks

please give me some details.

Thanks

4 Replies

  • EngWei_O_Intel's avatar
    EngWei_O_Intel
    Icon for Frequent Contributor rankFrequent Contributor

    Hi Minkyo


    Thanks for your inquiry. May I know if your input reference clock is misaligned with PLL's output clock? Or do you mean you have multiple PLL's outclocks misaligned?


    Thanks.

    Eng Wei


    • minkyo's avatar
      minkyo
      Icon for New Contributor rankNew Contributor

      Hi

      Thank you for the answer.

      I mean, the output clocks misaligned.

      For example, when Plll outputs a,b,c, a,b,c are not aligned each other.

      Could I make output clocks aligned ?

      Thanks

      • EngWei_O_Intel's avatar
        EngWei_O_Intel
        Icon for Frequent Contributor rankFrequent Contributor

        Hi Minkyo

        Sorry for late response. May I know which PLL or fPLL you are using? Are you able to get the exact output freq 12.288Mhz, 3.072Mhz, and 48KHz? If the exact freq isn't available, you the outclk might be misaligned.

        Thanks.

        Eng Wei