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Altera_Forum
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16 years ago

PLL megacore probs.build my own??

Hi all, I want to implement a PLL that will lock onto & track an incoming signal of about 30KHz and output a multiple of that locked frequency. I tried using Quartus's PLL megacore function but...
Altera_Forum's avatar
Altera_Forum
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16 years ago

Looking at the PLL hardware specification clarifies, that it can't use a 30 kHz reference clock. Without going too deep into details, it's simply impossible for a PLL with a 0.5 to 1 GHZ VCO range.

Designing "your own" PLL is actually an option. But an low frequency equivalent to the FPGA PLL would be rather a basic all digtal PLL than a NCO design dealing with digitized waveform. Although the latter is also feasible, of course.