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Altera_Forum
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12 years ago

PLL Megafunction actual clock frequency

Hi, I am using the Altera PLL Megafunction to generate 6 different clocks (100, 125, 200,50, 1MHz) with a reference clock of 100 MHz. I set all the frequencies correctly except for the 1 MHz c...
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Altera_Forum
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12 years ago

You didn't tell about the involved Altera device so we don't even know if the PLL supports frequencies down to 1 MHz. But apparently, there's a conflict with available PLL parameters.

It ususally doesn't make sense to use low requencies like 1 or 2 MHz as design clock. You can use a regular design clock in the 10 to 50 MHz range and generate a 1 MHz clock enable by a divider.