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Altera_Forum
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18 years ago

will Cyclone III work with unconected VCCA PLL ??

I actually made e board already and didn't connected thous VCCA PLL pins and now my board don't work (I can't program it and software all time is saying "can't access JTAG chain" is that because...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
18 years ago

Hello,

manual specification is clear in this respect:

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All VCCA pins must be powered to 2.5-V (even when PLLs are not used), and must be powered-up and powered-down at the same time.

--- Quote End ---

The same is stated in the Pinout document. Please don't ask what happens, if you ignore it. Did you see configuration functional with only VCCA1 connected?

Regards,

Frank