Digital Logic Design

Digital Logic Design – CS302

Question No:1       ( Marks:1 )       – Please choose one

A SOP expression is equal to 1

► All the variables in domain of expression are present

► At least one variable in domain of expression is present.

► When one or more product terms in the expression are equal to 0.

When one or more product terms in the expression are equal to 1.

Question No:2       ( Marks:1 )       – Please choose one

The output A < B is set to 1 when the input combinations is

► A=10, B=01

► A=11, B=01

► A=01, B=01

A=01, B=10

Question No:3       ( Marks:1 )       – Please choose one

Two 2-bit comparator circuits can be connected to form single 4-bit comparator

True

► False

Question No:4      ( Marks:1 )       – Please choose one

High level Noise Margins (VNH) of CMOS 5 volt series circuits is

0.3 V

► 0.5 V

► 0.9 V

► 3.3 V

Question No:5      ( Marks:1 )       – Please choose one

If we multiply “723” and “34” by representing them in floating point notation i.e. by first, converting them in floating point representation and then multiplying them, the value of mantissa of result will be

24.582

► 2.4582

► 24582

► 0.24582

Question No:6      ( Marks:1 )       – Please choose one

The output of the expression F=A+B+C will be Logic  when A=0,B=1,C=1. the symbol‟+‟here represents OR Gate.

► Undefined

One

► Zero

► 10 (binary)

Question No:7      ( Marks:1 )       – Please choose one

If an active-HIGH S-R latch has a 0 on the S input and a 1 on the R input and then the R input goes to 0, the latch will be

SET

► RESET

► Clear

► Invalid

Question No:8      ( Marks:1 )       – Please choose one

  • v CMOS series is characterized by and as compared to the 5 v CMOS series.

► Low switching speeds, high power dissipation

► Fast switching speeds, high power dissipation

Fast switching speeds, very low power dissipation

► Low switching speeds, very low power dissipation

Question No:9      ( Marks:1 )       – Please choose one

The binary value “1010110” is equivalent to decimal_

86

► 87

► 88

► 89

Question No:10      ( Marks:1 )       – Please choose one

The  _______ Encoder is used as a keypad encoder.

2-to-8 encoder

► 4-to-16 encoder

► BCD-to-Decimal
►Decimal-to-BCD Priority

Question No:11      ( Marks:1 )       – Please choose one

How many data select lines are required for selecting eight inputs?

► 1

► 2

► 3

► 4

Question No:12      ( Marks:1 )       – Please choose one

The Quad Multiplexer has         outputs

► 4   

► 8

► 12

► 16

Question No:13      ( Marks:1 )       – Please choose one

De-multiplexer has

► Single input and single outputs.

► Multiple inputs and multiple outputs.

► Single input and multiple outputs.

► Multiple inputs and single output.

Question No:14      ( Marks:1)        – Please choose one

“Sum-of-Weights” method is used

to convert from one number system to other

► to encode data

► to decode data

► to convert from serial to parallel data

Question No:15      ( Marks:1 )       – Please choose one

The maximum number that can be represented using unsigned octal system is

► 1

7

► 9

► 16

Question No:16      ( Marks:1 )       – Please choose one

The range of Excess-8 code is from  _________  to

► +7 to -8

► +8 to -7

► +9 to -8

► -9 to +8

Question No:17      ( Marks:1 )       – Please choose one

The 3-variable Karnaugh Map(K-Map) has            cells for min or max terms

► 4

8

► 12

► 16

Question No:17    ( Marks:1 )       – Please choose one

The binary numbers A = 1100 and B = 1001 are applied to the inputs of a comparator. What are the output levels?

► A > B = 1, A < B = 0, A < B = 1

► A > B = 0, A < B = 1, A = B = 0

A > B = 1, A < B = 0, A = B = 0

► A > B = 0, A < B = 1, A = B = 1

Question No:18    ( Marks:1 )       – Please choose one

A particular Full Adder has

3 inputs and 2 output       

► 3 inputs and 3 output

► 2 inputs and 3 output

► 2 inputs and 2 output

Question No:19    ( Marks:1 )       – Please choose one

The function to be performed by the processor is selected by set of inputs knownas

► Function Select Inputs        

► Micro Operation selectors

► OPCODE Selectors

► None of given option

Question No:20      ( Marks:1 )       – Please choose one

For a 3-to-8 decoder how many 2-to-4 decoders will be required?

2

► 1

► 3

► 4

Question No:21      ( Marks:1 )       – Please choose one

GAL is an acronym for               .

► Giant Array Logic

► General Array Logic

Generic Array Logic

► Generic Analysis Logic

Question No:22      ( Marks:1 )       – Please choose one

A.(B.C) = (A.B).C  is an expression  of

► Demorgan‟s Law

► Distributive Law

► Commutative Law

Associative Law    

Question No:23      ( Marks:1 )       – Please choose one

2’s complement of any binary number can be calculated by

► adding 1’s complement twice

adding 1 to 1’s complement          

► subtracting 1 from 1’s complement.

► calculating 1’s complement and inverting Most significant bit

Question No:24      ( Marks:1 )       – Please choose one

The binary value “1010110” is equivalent to decimal

86   

► 87

► 88

► 89

Question No:25      ( Marks:1 )       – Please choose one

Tri-State Buffer isbasicallya/an                  gate.

► AND

► OR

► NOT

XOR    

Question No:26      ( Marks:1 )       – Please choose one

The binary value “11011” is equivalentto

1B

►1C

►1D

►1E

Question No:27      ( Marks:1 )       – Please choose one

An important application of AND Gate is its use in counter circuit

True 

►False

Question No:28      ( Marks:1 )       – Please choose one

The OR Gate performs Boolean __________  function

Addition

►Subtraction

►Multiplication

►Division

Question No:29      ( Marks:1 )       – Please choose one

TTL based devices work with a dc supply of              Volts

►+10

+5

►+3

►+4

Question No:30      ( Marks:1 )       – Please choose one

A standard POS form has ___________  terms that have all the variables in the domain of the expression.

Sum        

►Product

►Min

►Composite

Question No:31      ( Marks:1 )       – Please choose one

A SOP expression having a domain of 3 variables will have a truthtablehaving                                                                                                                                                 combinations of inputs and corresponding output values.

►2

►4

8  

►16

Question No:32      ( Marks:1 )       – Please choose one

A BCD to 7-Segment decoderhas

►3 inputs and 7 outputs

4 inputs and 7 outputs 

►7 inputs and 3 outputs

► inputs and 4 outputs

Question No:33      ( Marks:1 )       – Please choose one

In the Karnaugh map shown above, which of the loops shown represents a legal grouping?

►A

►B

C

►D

Question No:34      ( Marks:1 )       – Please choose one

The binary value of 1010 is converted to the product term

►True

►False

Question No:35      ( Marks:1 )       – Please choose one

The binary numbers A = 1100 and B = 1001 are applied to the inputs of a comparator. What are the output levels?

►A > B = 1, A < B = 0, A < B = 1

►A > B = 0, A < B = 1, A = B = 0

A > B = 1, A < B = 0, A = B= 0     

►A > B = 0, A < B = 1, A = B = 1

Question No:36      ( Marks:1 )       – Please choose one

Cout1 +S3 (S2 +S1 ) is Boolean expression for

►Half Adder

Full Adder

►The Invalid BCD Detector Circuit

►Parity Checker

Question No:37      ( Marks:1 )       – Please choose one

3-to-8 decoder can be used to implement Standard SOP and POS Boolean expressions

True       

►False

Question No:38      ( Marks:1 )       – Please choose one

The GAL22V10 has           inputs

22

►10

►44

►20

Question No:39      ( Marks:1 )       – Please choose one

A latch retains the stateunless

►Power is turned off

►Input is changed

Output is changed

►Clock pulse is changed

Question No:40      ( Marks:1 )       – Please choose one

If an active-HIGH S-R latch has a 0 on the S input and a 1 on the R input and then the Rinput goes to 0, the latchwillbe                                 .

SET

►RESET

►Clear

►Invalid

Question No:41      ( Marks:1 )       – Please choose one

Consider a circuit consisting of two consecutive NOT gates, the entire circuit belongs to a CMOS 5 Volt series, if certain voltage is applied on the input, the output voltage of Logic high signal (VoH) will be in the range of  _____________________  volts.

►4 to 4.5

4.5 to 5

►0 to 4.5

►0 to 3.5

Question No:42      ( Marks:1 )       – Please choose one

A.(B.C) = (A.B).C  is an expression of

►Demorgan‟s Law

►Distributive Law

►Commutative Law

►Associative Law

Question No:43      ( Marks:1 )       – Please choose one

Which of the number is not a representative of hexadecimal system

►1234

►ABCD

►1001

►DEHF

Question No:44      ( Marks:1 )       – Please choose one

GAL is an acronymfor              .

► Giant Array Logic

► General Array Logic

► Generic Array Logic

► Generic Analysis Logic

Question No:45      ( Marks:1 )       – Please choose one

Sequential circuits have storageelements

True

False

Question No:46      ( Marks:1 )       – Please choose one

The Programmable Array Logic(PAL)has             AND array and a        OR array

Fixed, programmable

Programmable, fixed

Fixed,fixed

Programmable, programmable

Question No:47      ( Marks:1 )       – Please choose one

The ABEL symbol for “XOR” operation is

► $

► #

► !

► &

Question No:48      ( Marks:1 )       – Please choose one

Sequential circuits have storage elements

► True

► False

Question No:49      ( Marks:1 )       – Please choose one

A latch has          stable states

► One

► Two

► Three

► Four

Question No:50      ( Marks:1 )       – Please choose one

An S-R latch can be implemented by using  ________ gates

► AND, OR

NAND, NOR 

► NAND, XOR

► NOT, XOR