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SZand's avatar
SZand
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7 years ago
Solved

MAX10 using external PLL with soft-lvds gives always a warning: Warning (15064): PLL... jitter performance depends on switching rate of other design elements. Use PLL dedicated clock outputs to ensure jitter performance

the LVDS signals are connected to a tft display. The picture is ok so far only, but after each comilation and program the fpga with more or less jitter. Compilation give the warning: Warning (15064...
  • JonWay_altera's avatar
    7 years ago

    Hi @SZand

    Let me sum it up. There are 2 issues

    1) warning on non-dedicated output clock

    2) sdc constraint output paths

    For (2), you might want to put on a new thread and refer to this thread so that my colleague could take detail look into your case.

    For (1), Pll-c3(1:1): LVDS-clockpins which was supposedly your tx_outclock, should be connected to dedicated PLL clock output pin (e.g. PLL_L_CLKOUTp). Example pin 32/33.

    50/52 is not a dedicated PLL clock output pin (e.g. PLL_L_CLKOUTp). Thus the warning.

    There isnt any sdc constraint that can dismiss the warning.