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Altera_Forum's avatar
Altera_Forum
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15 years ago

Clk osc stability for Cyclone III

Dear experts,

What is the clock oscillator stability needed for Cyclone III? Is +/- 250ppm fair enough to clock the device?

Kindly advise & thx,

Skw

1 Reply

  • Altera_Forum's avatar
    Altera_Forum
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    Cyclone III doesn't require a particular frequency accuracy (that's, what's indicated with the ppm quantity). For PLL operation, clock jitter must not exceed a certain limit. But it's usually achieved by all kinds of crystal oscillators.