Question 19: Semiconductors and Logic Gates

Question

$$ 	ext { The given circuit works as : } $$

Accepted Answer

The circuit is composed entirely of NOR gates. A NOR gate with its inputs tied together (or receiving the same signal) acts as a NOT gate.
If input is $A$, the output is $\overline{A+A}=\bar{A}$
$$ \begin{array}{|l|l|l|l|} \hline 	ext { Input 1 } & 	ext { Input 2 } & 	ext { OR Output } & 	ext { NOR Output } \ \hline 1 & 1 & 1 & 0 \ \hline 0 & 0 & 0 & 1 \ \hline \end{array} $$
$$ \begin{array}{|l|l|l|l|l|l|} \hline \mathrm{A} & \mathrm{~B} & \mathrm{Y}_1=\overline{\mathrm{A}} & \mathrm{Y}_2=\overline{\mathrm{B}} & \mathrm{Y}_3=\overline{\mathrm{Y}_1+\mathrm{Y}_2} & \mathrm{Y}_4=\overline{\mathrm{Y}_3} \ \hline 1 & 1 & 0 & 0 & 1 & 0 \ \hline 1 & 0 & 0 & 1 & 0 & 1 \ \hline 0 & 1 & 1 & 0 & 0 & 1 \ \hline 0 & 0 & 1 & 1 & 0 & 1 \ \hline \end{array} $$
The final expression $\mathrm{Y}=\overline{\mathrm{A} \cdot \mathrm{B}}$ is the characteristic equation for a NAND gate.
Therefore, the circuit functions as a NAND gate.
Hence, the correct option is (D).

Answer

NOR gate

Answer

OR gate

Answer

AND gate

Answer

NAND gate

Semiconductors and Logic Gates

\text { The given circuit works as : }

Choose the correct answer: