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Altera_Forum's avatar
Altera_Forum
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8 years ago

Cyclone II PLL clock multiplier

Hi, I'm looking for a way to take an unknown external clock in the range 1-5MHz and from it generate an internal clock that is exactly four times that external clock. I've been reading various...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
8 years ago

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Hi,

External clock in range 1-5MHz is to slow to work for Altera Cyclone II or IV PLL. As I remember Cyclone IV PLL input clock frequency is min 5MHz and Cyclone II - 10MHz.

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Thanks - it's good to have a definitive answer, even though it's not the one I was hoping for :)