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Altera_Forum
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8 years ago

Buffer chain output from DLL in ALTDLL

Hi, I require clocks with different phase shifts. Theoretically, the outputs at each stage of the buffers in the buffer chain of DLL in ALTDLL megafunction should do it. However, ALTDLL outputs only ...
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Altera_Forum
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8 years ago

Not sure what device you're looking at, but usually those delaytaps go directly into a mux and only one is selected. There is not an individual driver for each one into the fabric. For multiple phases, users generally take a PLL and have it's outputs drive 0/45/90/135 and then invert it(which is done for free at the LAB level) for the other phases. There is no digital logic, as the PLL has multiple counter outputs.