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Altera_Forum
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9 years ago

ALTPLL for multiple input frequencies

Hi All, I have an input clock to MAX-10, which could be 2.5MHz, 25MHz, and 250MHz. I need to put a PLL on this input clock (for shifting the input clock by 90 degrees). I don't have...
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Altera_Forum
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9 years ago

Altera PLLs have a maximum lock range of about 1:2. Also constraints for PFD frequency range.

Changing input frequency over a wider range would require PLL reconfiguration or multiple PLLs. Also input frequency of 2.5 MHz is below specified MAX10 range.