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Altera_Forum
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13 years ago

pll_lock does not lock but the pll works

Hello, If i'm not wrong pll_lock works by positive logic, so i have this problem: My PLL Works but doesn't lock, anyone knows why? http://i46.tinypic.com/11lshsg.jpg As you can see CLO...
Altera_Forum's avatar
Altera_Forum
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13 years ago

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As said, the PLL model is simulating some locking delay (in a 10 µs range, if I remember right).

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Ok, sorry, my time period is 40 ns so it should lock in about 300 clocks, my window of 10 clocks is clearly insufficient, that may be a reason.

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Finally, PLL simulation doesn't work with default ns Modelsim timescale, it has to be changed to ps.

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Why more precision?, Thank you.