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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

Hi Simon -

I recommend just following the guidelines provided by Altera for Cyclone IV:

https://www.altera.com/content/dam/altera-www/global/en_us/pdfs/literature/dp/cyclone-iv/pcg-01008.pdf

https://www.altera.com/content/dam/altera-www/global/en_us/pdfs/literature/an/an592.pdf

Unless specifically advised otherwise by an IC vendor (even then take it with a grain of salt) your best bet is always to drop a via to a solid ground plane vs routing a trace to a ground pin. And do not split the ground plane for Cyclone IV.

Hope that helps.

Bob