Digital Circuits

Question 1

1. In analytical instrumentation, little circuitry is concerned with the amplification and processing of signals.
   a) True
   b) False

Answer 1

b) False

Question 2

2. Which of the following samples the analog signals to
   obtain their digital equivalent?
   a) Analog to digital converter
   b) Electronic counter
   c) Comparator
   d) Digital to analog converter

Answer 2

a) Analog to digital converter

Question 3

3. Which of the following can be used to store
   information?
   a) Gates
   b) ADC
   c) DAC
   d) Flip-flops

Answer 3

d) Flip-flops

Question 4

4. Which of the following is known as a nibble?
   a) 1 bit
   b) 4 bits
   c) 8 bits
   d) 16 bits

Answer 4

b) 4 bits

Question 5

8. Two switches are in parallel and are connected with a lamp and supply in series. This represents which of the following logic gate?
   a) AND gate
   b) OR gate
   c) EX-OR gate
   d) NOT gate

Answer 5

b) OR gate

Question 6

5. Which of the following is the binary equivalent of the decimal number 10?
   a) 1100
   b) 1010
   c) 1011
   d) 1110

Answer 6

b) 1010

Question 7

6. 1001 is a data presented on a set of binary coded
   decimal output lines. What would be the decimal
   equivalent of this number in the case of negative logic?
   a) 9
   b) 6
   c) 1
   d) 8

Answer 7

b) 6

Question 8

9. The output will be logic ‘1’ only if all the inputs are ‘0’. Which gate must be used to execute this condition?
   a) AND gate
   b) NAND gate
   c) NOR gate
   d) EX-OR gate

Answer 8

b) NAND gate

Question 9

10. INHIBIT gate is ________ gate with an inhibiting input.
    a) AND gate
    b) OR gate
    c) EX-OR gate
    d) NOT gate

Answer 9

b) OR gate

Question 10

2. The basic function of TTL gate is which of the following functions?
   a) AND
   b) OR
   c) NOR
   d) NAND

Answer 10

d) NAND

Question 10

1. Which of the following is the most widely employed
   logic family?
   a) Emitter-coupled logic
   b) Transistor-transistor logic
   c) CMOS logic family
   d) NMOS logic

Answer 10

b) Transistor-transistor logic

Question 10

3. In TTL logic, the input transistor has a number of
   ________ equal to the desired fan-in of the circuit.
   a) Base
   b) Collect
   c) Emitter
   d) Gate

Answer 10

c) Emitter

Question 11

4. Which of the following is the propagation delay of TTL circuits?
   a) 1 s
   b) 1 ms
   c) 1 ns
   d) 1 ps

Answer 11

c) 1 ns

Question 11

5. The standard TTL gates are marketed as _______ series.
   a) 80
   b) 82
   c) 74
   d) 08

Answer 11

c) 74

Question 11

8. ECL is a way of achieving a higher speed of gate.
   a) True
   b) False

Answer 11

a) True

Question 11

6. Schottky TTL logic family does not have which of the
   following features?
   a) Good fan-in
   b) Good fan-out
   c) High speed capability
   d) High propagation delay

Answer 11

d) High propagation delay

Question 11

7. The logic ‘0’ of ECL is represented as ______V and logic ‘1’ is represented as ______V.
   a) 1, 1.65
   b) 0.9, 1.75
   c) 1.2, 2.35
   d) 1.9, 4.3

Answer 11

b) 0.9, 1.75

Question 12

11. The switching of MOS gates can be improved by using CMOS.
    a) True
    b) False

Answer 12

a) True

Question 12

10. CMOS gates are commercially available as which of the following series?
    a) 1000
    b) 2000
    c) 3000
    d) 4000

Answer 12

d) 4000

Question 12

9. Which of the following is not the advantage of MOS
   gates?
   a) Low power dissipation
   b) Small size
   c) Good immunity to noise
   d) High switching speeds

Answer 12

d) High switching speeds