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Altera_Forum
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16 years ago

Does PLL VCCA require isolation if PLL isn't used?

Hi Folks, I'm currently designing a board with an EP1C3T100 that doesn't use the PLL. When checking the Cyclone manual for board layout best practice it recommends isolating VCCA. I quote - ...
Altera_Forum's avatar
Altera_Forum
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16 years ago

The purpose for isolating the power to the PLL is to minimize jitter on the PLL's clock outputs. If you're not using the PLL, no need to reduce the jitter. Still, I'd at least follow FvM's guidelines and add proper bypass.

Jake