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Altera_Forum
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9 years ago

CycloneIV VCCD_PLL Decoupling

Hi, what is the appropriate ground connection for the VCCD_PLL pins? None of these have GND pins nearby in the E22 package, but the name suggests that this is a digital pin, so it is refer...
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Altera_Forum
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9 years ago

I've set up the bypass caps for VCCINT and VCCIO like

https://www.alteraforum.com/forum/attachment.php?attachmentid=13326

in order to get these voltages as stable as possible. The same thing works for VCCA, but with VCCD_PLL I'm lost here:

https://www.alteraforum.com/forum/attachment.php?attachmentid=13327

So far, it's attached to a via to the ground plane, but I think this could be done better. Neither the PCG nor the checklist give an indication what the return path for these pins is.

Simon