Electronics and Communication Engineering - Digital Electronics

26. 

A 12 bit ADC is used to convert analog voltage of 0 to 10 V into digital. The resolution is

A. 2.44 mV
B. 24.4 mV
C. 1.2 V
D. none of the above

Answer: Option A

Explanation:

.


27. 

For the truth table of the given figure Y =

A. A + B + C
B. A + BC
C. A
D. B

Answer: Option D

Explanation:

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


28. 

A full adder can be made out of

A. two half adders
B. two half adders and a OR gate
C. two half adders and a NOT gate
D. three half adders

Answer: Option B

Explanation:


29. 

If the functions w, x, y, z are as follows.
w = R + PQ + RS ,
x = PQR S + PQR S + PQ R S


Then

A. w = z x = z
B. w = z, x = y
C. w = y
D. w = y = z

Answer: Option A

Explanation:

Use k-map, then it will be easy.


30. 

The output of a half adder is

A. SUM
B. CARRY
C. SUM and CARRY
D. none of the above

Answer: Option C

Explanation: