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We need to determine the equivalent logic operation carried out by the given digital circuit arrangement.
From the schematic layout, the circuit consists of three logic gates connected in series:
When both input terminals of a NAND gate are shorted together, it functions strictly as an inverter (NOT gate):
$$X = \bar{A}$$
$$Y = \bar{B}$$
The signals $$X$$ and $$Y$$ serve as inputs to the final AND gate. The Boolean expression for the final output $$Z$$ is calculated as follows:
$$Z = X \cdot Y$$
Substituting the values of $$X$$ and $$Y$$ into the equation gives:
$$Z = \bar{A} \cdot \bar{B}$$
Applying De Morgan's Law ($$\bar{A} \cdot \bar{B} = \overline{A + B}$$), we can simplify the expression:
$$Z = \overline{A + B}$$
We can verify this Boolean expression by analyzing the state combinations of the truth table:
| $$A$$ | $$B$$ | $$X = \bar{A}$$ | $$Y = \bar{B}$$ | $$Z = X \cdot Y$$ |
|---|---|---|---|---|
| 0 | 0 | 1 | 1 | 1 |
| 0 | 1 | 1 | 0 | 0 |
| 1 | 0 | 0 | 1 | 0 |
| 1 | 1 | 0 | 0 | 0 |
The output truth value matches the standard operational behavior of a NOR logic gate, where the output is high ($1$) only when all inputs are low ($0$).
The logic operation carried out by the given circuit configuration is a NOR gate.
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