Physics - Semiconductors Question with Solution | TestHub

The given logic circuit consists of three gates connected in series.

The first gate is a NAND gate with inputs $A$ and $B$. Its output is $Y_1=\overline{A\cdot B}$.

The second gate is a NOR gate with both of its inputs tied together, which makes it act as a NOT gate. Its output is $Y_2=\overline{Y_1+Y_1}=\overline{Y_1}$.

The third gate is also a NOT gate. Its output is $Y=\overline{Y_2}=\overline{\overline{Y_1}}=Y_1$.

Since the two NOT gates in series cancel each other out, the final output is simply the output of the first gate, $Y=\overline{A\cdot B}$.

This is the boolean expression for a NAND gate.

Answer: NAND gate