Difficulty: Easy
Correct Answer: Correct
Explanation:
Introduction / Context:
The S–R latch (often called an S–R “flip-flop” informally) is the canonical memory element built from two cross-coupled gates. It is typically one of the first sequential circuits students design after learning basic logic gates and feedback principles.
Given Data / Assumptions:
Concept / Approach:
The design hinges on mutual reinforcement through feedback: one gate output feeds the other’s input. Applying S forces Q = 1 (set), applying R forces Q = 0 (reset), and releasing both maintains the state through cross-coupling. The schematic is small, symmetrical, and teaches hazards such as the invalid input combination for the chosen technology (NOR: S = R = 1; NAND: S̄ = R̄ = 0).
Step-by-Step Solution:
Verification / Alternative check:
Simulate with two gates; observe bistability and proper response. Minimal gate count and symmetry confirm design simplicity for instructional purposes.
Why Other Options Are Wrong:
Common Pitfalls:
Overlooking the invalid input case; confusing latch vs flip-flop terminology; forgetting active-level conventions between NOR and NAND implementations.
Final Answer:
Correct
Discussion & Comments