GATE ECE 2020 | Question: 10

Question

The figure below shows a multiplexer where $S_{1}$ and $S_{0}$ are the select lines, $I_{0}$ to $I_{3}$ are the input data lines, $\text{EN}$ is the enable line, and $\text{F(P, Q, R)}$ is the output. $\text{F}$ is 

                               

• A. $PQ+\overline{Q}R.$
• B. $PQ+Q\overline{R}.$
• C. $P\overline{Q}R+\overline{P}Q.$
• D. $\overline{Q}+PR.$

Comments

Detailed Video Solution: https://youtu.be/cKIeV9ktU8k 

Answer 1

The output equation of $F$ is as follows:

$\implies F= (\bar P\bar QI_0+\bar PQI_1+P\bar QI_2+PQI_3)*EN$

$\implies F=(\bar P\bar QR+\bar PQ*0+P\bar QR+PQ)*1$

$\implies F=\bar QR(P+\bar P)+PQ$

$\implies F=PQ+\bar QR$

Option A is correct.