digital circuits & logic design(engineering108.com)

7/31/2019 Digital Circuits & Logic Design(Engineering108.Com)

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# Syllabus........................................................................................................................................ 2

Intorduction............................................................................................................................... 2

Boolean Algebra........................................................................................................................ 2

Combinational Logical Circuits............................................................................................... 2

Sequential logical circuits......................................................................................................... 2

Counters..................................................................................................................................... 2

Registers..................................................................................................................................... 2

Detection and correction codes................................................................................................ 2

#1 Introduction............................................................................................................................... 6

Digital Computers..................................................................................................................... 6

Logic Gates ................................................................................................................................ 6

Gate Propagation Delay ........................................................................................................... 8

Universal Gates ......................................................................................................................... 8

NAND gate as a Universal Gate ............................................................................................. 8

#2 Boolean Algebra...................................................................................................................... 10

Boolean Algebra...................................................................................................................... 10

Boolean Operations................................................................................................................. 10

Basic Identities of Boolean Algebra....................................................................................... 10

DeMorgans theorem.............................................................................................................. 11

Complement of a function...................................................................................................... 12

Simplification using Karnaugh Maps ................................................................................... 12

Variable Maps....................................................................................................................... 12

Sum-of-Products Simplification ............................................................................................ 13

Product-of-Sums Simplification ............................................................................................ 15

NAND and NOR Implementation ........................................................................................ 17

Don't Care Conditions............................................................................................................ 17

#3 Combinational Logical Circuits ............................................................................................. 18

Combinational Circuits .......................................................................................................... 18

Half-Adder............................................................................................................................... 18

Full-Adder ............................................................................................................................... 18

Parallel Adder ......................................................................................................................... 19

Operation............................................................................................................................... 20

Serial Adder............................................................................................................................. 20


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Construction.......................................................................................................................... 20

Operation............................................................................................................................... 21

Subtractors .............................................................................................................................. 22

Half-subtractor ...................................................................................................................... 22

Full-subtractor....................................................................................................................... 22

Code Converters...................................................................................................................... 23

Decoders................................................................................................................................... 25

NAND Gate Decoder ............................................................................................................ 27

Decoder Expansion ............................................................................................................... 27

Encoders................................................................................................................................... 28

Multiplexer .............................................................................................................................. 29

DeMultiplexer.......................................................................................................................... 29

#4 Sequential logic circuits.......................................................................................................... 32

Flip-flops .................................................................................................................................. 32

SR Flip-Flop ............................................................................................................................ 32

SR Flip-Flop circuit with NAND gate .................................................................................. 33

D Flip-Flop............................................................................................................................... 33

D Flip-Flop with NAND gate ............................................................................................... 34

JK Flip-Flop ............................................................................................................................ 34

T Flip-Flop............................................................................................................................... 35

Master-Slave JK Flip-Flop..................................................................................................... 36

Flip-Flop Excitation Tables.................................................................................................... 37Sequential Circuits.................................................................................................................. 38

Design Procedure .................................................................................................................. 38

#5 Registers .................................................................................................................................. 39

Registers................................................................................................................................... 39

Shift Registers.......................................................................................................................... 40

Bidirectional Shift Register with parallel load..................................................................... 40

Application of Shift Registers ................................................................................................ 41

#6 Counters .................................................................................................................................. 42Introduction............................................................................................................................. 42

Binary Counters ...................................................................................................................... 42

Synchronous Counters .......................................................................................................... 42

Up counters ....................................................................................................................... 42

Binary Up-Down counters ................................................................................................ 43

Asynchronous counters ......................................................................................................... 43


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Up Counters ...................................................................................................................... 43

Down counters .................................................................................................................. 44

Error detection and correction codes.................................................................................... 44


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#1 Introduction

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