7476 vs. 74LS76 — family and triggering style What is the correct relationship between the classic 7476 and the 74LS76 J–K flip-flop devices with preset and clear?

Introduction / Context:
The 74xx TTL family and the 74LSxx low-power Schottky TTL family include many functionally equivalent parts with different speed and power characteristics. The 7476 and 74LS76 are both dual J–K flip-flops with asynchronous preset and clear. It is easy to confuse these with strictly edge-triggered variants such as the 74LS109, so knowing which are master–slave helps you read datasheets correctly and design reliable counters and registers.

Given Data / Assumptions:

• Both parts implement J–K flip-flops with preset and clear.
• Part numbering: 7476 (standard TTL), 74LS76 (low-power Schottky).
• We are distinguishing master–slave vs. edge-triggered operation.

Concept / Approach:
Master–slave J–K flip-flops effectively sample on one phase and transfer on the opposite phase of the clock, achieving edge-like behavior but using two level-sensitive stages. Datasheet summaries and logic diagrams show that both 7476 and 74LS76 are master–slave devices; truly edge-triggered J–K devices carry different part numbers (e.g., 74LS109, 74LS112 families).

Step-by-Step Solution:

Verification / Alternative check:
Cross-reference catalog listings: 7476/74LS76 are master–slave; 74LS109 is explicitly positive edge-triggered, highlighting the architectural distinction.

Why Other Options Are Wrong:

• Both edge-triggered: confuses them with 74LS109-type devices.
• Mixed claims (edge vs. master–slave): contradict canonical datasheets.

Common Pitfalls:
Equating LS variants with functional changes; LS affects speed/power, not the fundamental logic function.

Final Answer:
the 7476 is master-slave, the 74LS76 is master-slave