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Altera_Forum
Honored Contributor
16 years agoCyclone III, huge cap at VCCD_PLL
Hi All! Altera document "Cyclone® III Device Family Pin Connection Guidelines PCG-01003-1.0" says that 470 uF capacitor must be used at digital power of PLL (besides a lot of ceramic capacitor...
Altera_Forum
Honored Contributor
16 years agoSome interesting reads:
http://www.altera.com/literature/an/an574.pdf http://www.altera.com/literature/an/an583.pdf I would not use a 470uF bulk cap on the VCCD_PLL rail. With the amount of current you are likely to be drawing, you might at most put a 10uF ceramic (besides the high frequency bypass). I typically put a 1uF a 10uF ceramic in addition to the high frequency bypass. Jake