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Altera_Forum
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15 years ago

Negative slack on TimeQuest report

Hello everybody I'm getting some negative slack messages on TimeQuest Timing Analyzer. I have one input clock and one PLL with one clock output in my system. But all of these messages are r...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

Hi Cris

Back on this problem again.

I'm actually using this options you've mentioned. I still have some negative slacks there.

One example is the following:

Slack: -1.767

From node: RST_N (it's actually an input pin from my system)

To node: rst_debounce:inst4|input_sync (it's actually the first register on synchonizer chain for this specific input)

Launch clock: CLK (it's the only global clock, PLL input for my system)

Latch clock: altpll1:inst7|altpll:altpll_component|altpll_34o2:auto_generated|clk[0] (it's one of my pll outputs, generated by "derive_pll_clocks"

Relationship: 0.100

Clock skew: 0.018

Data delay: 1.264

Not sure how should I handle this...