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Altera_Forum
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11 years ago

27 MHz from 50 or 125 MHz?

Hello all, I am working on a project in which I need a 27MHz clock for the VGA interface. I am using Cyclone III 3c120 FPGA and it has only 50MHz and 125MHz oscillators. Can I get 27M...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
11 years ago

You can easily calculate that 27 MHz can be achieved with small integer ratios. The problem may be that you are trying to generate another frequency with the same PLL which doesn't fit the divider parameters. In this case use two PLLs.