How to design a clock divide-by-3 circuit with 50% duty cycle?
This content is from the following blog:
vlsiwizard.blogspot.com/2008/01/design-clock-divide-by-3-circuit-with.html
The basic insight was to notice that if you are doing a divide by 3 and want to keep the duty cycle at 50% you have to use the falling edge of the clock as well.
The trick is how to come up with a minimal design, implementing as little as possible flip-flops, logic and guaranteeing glitch free divided clock.
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