Forum Discussion

hemi's avatar
hemi
Icon for New Contributor rankNew Contributor
3 months ago
Solved

MAX10 second PLL issue

Hello, This is my configuration: Device MAX10 (10M16DCF256C8G) Quartus Prime Version 24.1std Build 1077 I need to use a second PLL, but it is not working. I have tried very hard and read the user...
  • hemi's avatar
    hemi
    3 months ago

    I found the cause.

    That was a good example of rubber duck debugging.

    With the answers from @FvM and @ShengN_Intel in mind, I simplified the design until only the PLLs remained.

    Now I noticed that PLL_3 never worked. And that was strange.

    The cause was quickly found: in the hardware design, we forgot to connect the power supply for PLL_3 (VCCD_PLL3, PIN_D4).

    How annoying! Fortunately, I can switch to PLL_2.

    Thank you very much for your support. It was a great help.

    Regards,

    Helmut

ShengN_altera's avatar
ShengN_altera
Icon for Super Contributor rankSuper Contributor
3 months ago

Hi,


Please check this document page 31 https://cdrdv2-public.intel.com/666937/ug_m10_clkpll-683047-666937.pdf

Two PLLs are cascaded to each other through the clock network. If your design cascades PLLs, the source (upstream) PLL must have a low-bandwidth setting and the destination (downstream) PLL must have a high-bandwidth setting.


And page 53 for Programmable Bandwidth Parameter Settings.


Thanks,

Regards,

Sheng



hemi's avatar
hemi
Icon for New Contributor rankNew Contributor
3 months ago

Thank you for your prompt reply!
Yes, I saw that note. But I must admit that I didn't follow it consistently.
So, I'll try again.

Regards,
Helmut