Forum Discussion

Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
13 years ago

ring oscillator as a clock

Hi, I am having a problem using 2 ring oscillators as 2 different clocks to 2 8-bit counters. When I use them separately they are working. But when I combine the two circuits in one design the out...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
13 years ago

I presume, it's a trivial timing failure.

You didn't tell about the involve FPGA family, but besides the problems addressed by kaz, it seems like the frequency of your ring oscillator is beyond feasible clock speeds. Timing closure for the counters has to be evaluated manually because the timing analyzer isn't prepared to determine the frequency of ring oscillators.