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Altera_Forum
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19 years ago

VCCA_PLLn

I know the Stratix II device handbook says I must connect the VCCA_PLLn even if I'm not using PLLn. But do I really have to? What will happen if I don't? I want to save all the power I can.
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Altera_Forum
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19 years ago

I expect that the side effects would be extra noise induced in the device, and it may draw more current than expected - due to portions of the unpowered analog PLL circuit feeding digital portions of the PLL circuit, causing the digital portion to unintentionally switch - creating the extra noise and current draw.