Question

Which logic gate is given in the figure?

• A. XOR
• B. NOR
• C. NAND
• D. OR

Hint:

In digital logic, the NAND gate is one of the most important gates as it is functionally complete, meaning any other gate can be constructed using only NAND gates.

Answer 1

The Correct Option is C

To identify the logic gate in the given figure, we need to analyze the components and the logic operation depicted:

The diagram shows the following logic gate configuration:

• The inputs A and B are first passed through NOT gates, which inverts the inputs.
• The inverted outputs are then fed into an OR gate.
• The output of the OR gate is again inverted by a NOT gate at the end.

This configuration describes a NAND gate but with a different arrangement. Let's evaluate why:

1. The combination of inverting inputs (NOT gates) and an OR gate performs a NOR operation for inputs A and B.
2. A final NOT gate inverts the output of the OR gate, changing the NOR operation to a NAND operation.

Thus, the overall operation performed by this setup is a NAND logic, where the output is the inversion of the AND operation.

To conclude, \(C = \overline{A \cdot B}\), which means the output is false only if both A and B are true, confirming the gate as a NAND gate.