Difficulty: Easy
Correct Answer: False
Explanation:
Introduction / Context:
A classic master–slave J–K flip-flop consists of two latches clocked on opposite phases. The “master” is enabled during one clock level, while the “slave” is enabled during the opposite level. Overall behavior appears edge-triggered because the slave transfers the master state only when the clock transitions. Understanding which clock level is sampled avoids timing mistakes.
Given Data / Assumptions:
Concept / Approach:
In a master–slave arrangement, one latch is transparent while the clock is at its active level and the other is opaque, then roles swap on the opposite level. Hence, for a positive-edge equivalent device, the master reads inputs during the HIGH level. The slave updates the output when the clock goes LOW, producing an effective edge-triggered transfer.
Step-by-Step Solution:
Identify the active sampling window: for positive-edge behavior, inputs affect the master while CLK is HIGH.Determine when outputs update: the slave becomes transparent when CLK goes LOW, passing the master state to the output.Compare with the claim: the statement says inputs are read during the entire LOW level, which is not the general case.Conclude the statement is incorrect.
Verification / Alternative check:
Timing diagrams show J and K gating the master while CLK is HIGH. When CLK falls, the slave latches the master state, yielding behavior indistinguishable from edge triggering.
Why Other Options Are Wrong:
Common Pitfalls:
Assuming the slave sampling window equals the input sampling window; confusing level-sensitive internal latches with the overall edge-triggered behavior.
Final Answer:
False
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