In a positive-edge-triggered JK flip-flop, if J and K both are high then the…
2016
In a positive-edge-triggered JK flip-flop, if J and K both are high then the output will be _____ on the rising edge of the clock.
- A.
No change
- B.
Set
- C.
Reset
- D.
Toggle
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Correct answer: D
JK flip-flop characteristic summary:
If J=0 and K=0 → No change: the next output equals the current output (Q(next) = Q(current)).
If J=0 and K=1 → Reset: the next output becomes 0 (Q(next) = 0).
If J=1 and K=0 → Set: the next output becomes 1 (Q(next) = 1).
If J=1 and K=1 → Toggle: the next output is the complement of the current output (Q(next) = not Q(current)).
Therefore, when both inputs are high on the rising clock edge of a positive-edge-triggered JK flip-flop, the output toggles. For example, if the current output is 0 it becomes 1 at the rising edge; if it is 1 it becomes 0.