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Altera_Forum
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14 years ago

Are CDC Synchronizers needed in this case

hi: If I have 2 clocks c1 and c2 which are derived from the same on chip pll and one is a divide by 2 of the other, then do I still need a 2-flop synchronizer in going from one clock domain to t...
Altera_Forum's avatar
Altera_Forum
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14 years ago

In general, no, you should not need synchronization registers when crossing the boundary between related clocks. You just need to specify the relationship between the clocks. Since these clocks are generated by an internal PLL, you can specify the clock relationship with derive_pll_clocks in the .sdc file.