Difficulty: Easy
Correct Answer: Correct
Explanation:
Introduction / Context:
The J–K flip-flop is edge-triggered in most logic families, meaning the next state is determined by inputs sampled at a specific clock edge. This question evaluates whether considering J and K only at the active edge is sufficient to determine the next state under normal, synchronous operating conditions.
Given Data / Assumptions:
Concept / Approach:
For an edge-triggered device, inputs are effectively sampled at the clock edge. The J–K characteristic table then determines the next state: J=0,K=0→no change; J=1,K=0→set; J=0,K=1→reset; J=1,K=1→toggle. Provided timing constraints are met, the values at that instant fully define the next output.
Step-by-Step Solution:
Verification / Alternative check:
Simulations and datasheets confirm that, absent violations and asynchronous actions, only edge-sampled values determine Q(n+1).
Why Other Options Are Wrong:
“Incorrect” would imply level-sensitive behavior, which contradicts edge-triggered operation. Limiting correctness to J=K or a specific edge polarity misunderstands the general rule.
Common Pitfalls:
Ignoring setup/hold, which can invalidate the assumption. Also, forgetting asynchronous set/clear can override edge-determined behavior if asserted.
Final Answer:
Correct
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