What logic function is implemented by the following circuit?

What logic function is implemented by the following circuit?

• 1. NOT gate
• 2. AND gate
• 3. Flip-flop
• 4. Latch

Step-by-Step Solution

1. Characterize the Component: The symbol represents a 2:1 Multiplexer (MUX). Input 'o' is selected when Sel=0, and input '|' is selected when Sel=1.

2. Write the Logic Equation: The output Y of a 2:1 MUX is given by:
Y = (¬Sel · I₀) + (Sel · I₁)

3. Substitute Circuit Connections:
From the diagram, I₀ = Y (feedback) and I₁ = A.
Plugging these in: Y = (¬Sel · Y) + (Sel · A).

4. Analyze Behavior:

• If Sel = 1, Y = A. The output follows the input (Transparent mode).
• If Sel = 0, Y = Y_prev. The output retains its previous value (Hold mode).

5. Identification: This behavior defines a level-triggered latch, where the select line acts as the enable signal.

Final Answer: The logic function is a Latch (Option 4).

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