Digital Circuit and Microprocessor MCQs

Question 1

The fan-in a logic gate refers to the number of

Accepted Answer

input terminals

Answer

input devices that can be connected

Answer

output terminals

Answer

circuits output can drive

Question 2

Which of the following statements regarding ICs is not correct

Accepted Answer

TTL has the lowest power consumption

Answer

ECL has the least propagation delay

Answer

TTL has the largest fan out

Answer

CMOS has the biggest noise margin

Question 3

The Boolean equation for NOR gate is

Accepted Answer

A + B = C

Answer

AB =C

Answer

X + = C

Answer

A+B = C

Question 4

The Boolean equation for a NAND gate is

Accepted Answer

X + 13- = C

Answer

A + B = C

Answer

AB = C

Answer

A+B = C

Question 5

The logic function of an invertor is

Accepted Answer

B = X

Answer

B =A

Answer

B = 71

Answer

None of these

Question 6

The simplified form of the Boolean expression Y = (X .BC + D) .D+) can be written as

Accepted Answer

.D + 1-3.D

Answer

AD + B. -E .D

Answer

(X +D)(171.C+ -15)

Answer

A. + BC.

Question 7

If a NAND latch has a 1 on the SET input and a 0 on the CLEAR input, then the SET input goes to 0, the latch will be :

Accepted Answer

HIGH

Answer

LOW

Answer

Invalid

Answer

None of these

Question 8

The invalid state of a NAND latch occurs when

Accepted Answer

S = 0, C = 0

Answer

S = 1, C = 0

Answer

S = 0, C = 1

Answer

S = 1, C=I

Question 9

The invalid state of a NOR latch occurs when

Accepted Answer

S =1, C =1

Answer

S =1, C =0

Answer

S =0, C = 1

Answer

S =0, C = 0