Semiconductor Electronics

The truth table for this given circuit is : [figure]

1. [figure]
2. [figure]
3. [figure]
4. [figure]

Answer

(2) [figure]

Solution

[figure]

Upper AND: inputs A, B AB; lower AND: inputs A, B AB

Y=AB+ AB=B(A+ A)=B

A+ A=1, the output simply follows B.

AB=00, 01, 10, 11 Y=0, 1, 0, 1

(A): Y=0,0,0,1 (AND) (A) is wrong

(B): Y=0,1,0,1 (Y=B) (B) is correct

(C): Y=1,0,1,0 (Y= B) (C) is wrong

(D): Y=1,1,1,0 (NAND) (D) is wrong

Answer: (2)