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Altera_Forum
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18 years ago

Cyclone III - PLL VCO range ?

Hello, What is the frequency range of CycloneIII PLL VCO ? PDF writes 600-1300MHz, but altpll withard creates PLLs with frequencies less than 350MHz. For PLL reconfiguration feature it's ...
Altera_Forum's avatar
Altera_Forum
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18 years ago

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I have tried using ALTPLL megawizard, which allows for generating frequency that can go upto 1300 MHz for input clock frequency of 48 MHz.

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Output frequency - that's clear. But VCO frequency is not the output frequency. After VCO, additional counter divisors exists, which creates final output. VCO should be upto 1600MHz. And the most interesting parameter - the lowest VCO frequency. Is it 600MHz? or 350MHz (like in altpll withard).