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Altera_Forum
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11 years ago

zero-delay buffer PLL issue

Hi, I've recently started using Altera's PLLs for a Cyclone V project. I'm creating a PLL, with the IP Wizard, with zero-delay buffer (zdbfbclk) mode enabled. I want to use the zdbfbclk port to dr...
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Altera_Forum
Icon for Honored Contributor rankHonored Contributor
11 years ago

Have a look at the altera iopll ip core user guide (http://www.altera.com/literature/ug/ug_altera_iopll.pdf). To quote from it:

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If you select the zero delay buffer mode, the PLL must feed an external clock output pin

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So yes, you must connect it up.

Regards,

Alex