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If both the inputs in SR latch are zero and there was no previous output then what would be the output? If both the NOR gates are different then depending which one is faster the output will be accordingly, but what if both are identical?
They can't be identical. One will always have slightly higher gain or speed. It also may by that the designers deliberately bias the SR Latch to favor one output.If both the NOR gates are different then depending which one is faster the output will be accordingly, but what if both are identical?
Why cannot they be identical ? Of course it would be very rare but still if they are then what?They can't be identical.
I think I know how they are configured and wired but maybe I have some misunderstanding. Help me understand it. I don't get why they can't be identicalI suspect you don't understand how the outputs are configured and wired together. If you did you would know the answer.
Even if all else is identical, random electrical noise will tip one output faster towards one state or the other, and this in turn forces the other output towards the complementary state.Why cannot they be identical ? Of course it would be very rare but still if they are then what?
Does this work? If phase of the S and R falling edge equals the mismatch then you're back into the same situation, no? It seems like the external rule imposed on the driving circuit of "don't let S and R falling edges be within the time of the worst case possible mismatch" is the only thing that works for the basic cross coupled latch.They can't be identical. One will always have slightly higher gain or speed. It also may by that the designers deliberately bias the SR Latch to favor one output.
Nevermind, I just realized it would get cleaned up on the next cycle around. So it is different in the sense that the oscillation doesn't persist.Does this work? If phase of the S and R falling edge equals the mismatch then you're back into the same situation, no? It seems like the external rule imposed on the driving circuit of "don't let S and R falling edges be within the time of the worst case possible mismatch" is the only thing that works for the basic cross coupled latch.
No, there is no chicken-egg situation with a SR flipflop.Okay I just figured out that I don't understand the basic SR latch properly. I am continuously finding myself in the chicken-or-egg first position.
Let's say S input is 1 and R input is 0. So for the first NOR gate to give input it has to get the output from the other NOR gate but it won't get it until it give its own output!
Maybe because I have not studied how a gate works internally I am having trouble but still if anyone can help me understand, it would be great.
Thank You