Table Of ContentDIGITAL
PRINCIPLES A D APPLICATIONS
Seventh Edition
Donald P Leach
Santa Clara University
Albert Paul Malvino
President, Ma/vino Inc.
Goutam Saha
Associate Professor
Department of Electronics and Electrical Communication Engineering
Indian Institute of Technology (/IT) Kharagpur
Tata McGraw Hill Education Private limited
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Digital Principles and Applications, 7e
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Preface to the Seventh Edition (SIE)
Preface
1. Digital Principles
Contents
1.1 Definitions for Digital Signals
2
1.2 Digital Waveforms
4
1.3 Digital Logic
8
1.4 Moving and Storing Digital Infom1ation
13
1.5 Digital Operations
17
1.6 Digital Computers 22
1.7 Digital Integrated Circuits
26
1.8 Digital IC Signal Levels
32
Summmy
35
Glossary
35
Problems 36
2. Digital Logic
2.1 The Basic Gates-NOT, OR, AND
40
2.2 Universal Logic Gates-NOR, NAND
48
2.3 AND-OR-Invert Gates
57
2.4 Positive and Negative Logic 59
2.5 Introduction to HDL
61
Summary
68
Glossary
69
Problems
69
Laborat01y Experiment
7 3
3. Combinational Logic Circuits
3.1 Boolean Laws and Theorems
75
3.2 Sum-of-Products Method 81
3.3 Truth Table to Kamaugh Map
84
3.4 Pairs, Quads, and Octets
86
3.5 Kamaugh Simplifications
89
3.6 Don't-care Conditions
93
3.7 Product-of-sums Method 95
3.8 Product-of-sums Simplification 98
3.9 Simplification by Quine-McClusky Method
102
xi
xv
1
40
74
3 .1 0 Hazards and Hazard Covers
104
3.11 HDL Implementation Models
108
Contents
Problem Solving with Multiple Methods
110
Summary
111
Glossary
112
Problems
112
Laboratory Experiment 116
4. Data-Processing Circuits
4.1 Multiplexers
118
4.2 Demultiplexers 127
4.3 1-of-16 Decoder
130
4.4 BCD-to-decimal Decoders
133
4.5 Seven-segment Decoders
136
4.6 Encoders
138
4.7 Exclusive-OR Gates
141
4.8 Parity Generators and Checkers
143
4.9 Magnitude Comparator 146
4.10 Read-only Memory 148
4.11 Programmable Array Logic
154
4.12 Programmable Logic Arrays
156
4.13 Troubleshooting with a Logic Probe
158
4.14 HDL Implementation of Data Processing Circuits
159
Problem Solving with Multiple Methods
161
Summary
163
Glossary
163
Problems
164
Laboratory Experiment 169
5. Number Systems and Codes
5 .1 Binary Number System 171
5 .2 Binary-to-decimal Conversion 17 3
5 .3 Decimal-to-binary Conversion 17 6
5.4 Octal Numbers
179
5.5 Hexadecimal Numbers
183
5.6 The ASCII Code
190
5.7 The Excess-3 Code
192
5.8 The Gray Code
193
5.9 Troubleshooting with a Logic Pulser 194
5 .10 Error Detection and Correction 196
Problem Solving with Multiple Methods
198
Summary
199
Glossary 200
Problems 200
Laboratory Experiment 205
118
171
Contents
6. Arithmetic Circuits
6.1 Binary Addition 207
6.2 Binary Subtraction 211
6.3 Unsigned Binary Numbers 212
6.4 Sign-magnitude Numbers 214
6.5 2's Complement Representation 216
6.6 2's Complement Arithmetic 220
6.7 Arithmetic Building Blocks 226
6.8 The Adder-subtracter 228
6.9 FastAdder 232
6.10 Arithmetic Logic Unit 235
6.11 Binary Multiplication and Division 237
6.12 Arithmetic Circuits Using HDL 237
Problem Solving with Multiple Methods
239
Summary 240
Glossary 241
Problems 241
Laboratory Experiment 243
206
7. Clocks and Timing Circuits
244
7.1 Clock Waveforms
244
7.2 TTL Clock 249
7.3 Schmitt Trigger 250
7.4 555 Timer-Astable 253
7.5 555 Timer-Monostable 256
7.6 Monostables with Input Logic
258
7.7 Pulse-forming Circuits
262
Problem Solving with Multiple Methods 264
Summa,y 265
Glossary 266
Problems 266
Laborato,y Experiment 268
8. Flip-Flops
270
8.1 RS FLIP-FLOPs 271
8.2 Gated FLIP-FLOPs
276
8.3 Edge-triggered RS FLIP-FLOPs 279
8.4 Edge-triggered D FLIP-FLOPs
281
8.5 Edge-triggered JK FLIP-FLOPs 283
8.6 FLIP-FLOP Timing 285
8.7 Edge Triggering through Input Lock Out 286
8.8 JK Master-slave FLIP-FLOPs 288
8.9 Switch Contact Bounce Circuits
289
8.10 Various Representations of FLIP-FLOPs 290
8.11 Analysis of Sequential Circuits 293
Contents
8.12 Conversion ofFLIP-FLOPs: A Synthesis Example 296
8.13 HDL Implementation of FLIP-FLOP 298
Problem Solving with Multiple Methods
301
Summa;y 303
GlossaTJ'
303
Problems 304
Laborat01y Etperiment 306
9. Registers
9.1 Types of Registers
309
9 .2 Serial In-serial Out 310
9.3 Serial In-parallel Out 313
9 .4 Parallel In-serial Out 316
9.5 Parallel In-parallel Out 320
9.6 Universal Shift Register 324
9.7 Applications of Shift Registers
325
9.8 Register Implementation in HDL 333
Problem Solving with Multiple Methods
334
Summmy 335
Glossmy 336
Problen1s
336
Laborat01y Experiment 339
10. Counters
10.1 Asynchronous Counters
342
10.2 Decoding Gates
346
10.3 Synchronous Counters
349
10.4 Changing the Counter Modulus
357
10.5 Decade Counters
363
10.6 Presettable Counters
368
10.7 Counter Design as a Synthesis Problem 376
10.8 A Digital Clock 381
10.9 Counter Design using HDL 384
Problem Solving with Multiple Methods
386
Summary 387
Glossary 388
Problems 388
Laboratmy Experiment 390
11. Design of Synchronous and Asynchronous Sequential Circuits
PART A: Design of Synchronous Sequential Circuit 393
11.1 Model Selection 393
11.2 State Transition Diagram 394
11.3 State Synthesis Table
396
11.4 Design Equations and Circuit Diagram 398
11.5 Implementation using Read Only Memory 400
308
341
392
Contents
11.6 Algorithmic State Machine
404
11. 7 State Reduction Technique 409
PART B: Asynchronous Sequential Circuit 413
11. 8 Analysis of Asynchronous Sequential Circuit 414
11.9 Problems with Asynchronous Sequential Circuits 417
11.10 Design of Asynchronous Sequential Circuit 419
11.11 FSM Implementation in HDL 423
Problem Solving with Multiple Methods
425
Summary 432
Glossary 432
Problems
433
Laboratory Experiment 435
12. D/ A Coversion and AID Conversion
438
12.1 Variable, Resistor Networks
439
12.2 Binary Ladders 442
12.3 DI A Converters 447
12.4. DI A Accuracy and Resolution 454
12.5 AID Converter-Simultaneous Conversion 455
12.6 AID Converter-Counter Method 458
12.7 Continuous ND Conversion 461
12.8 ND Techniques 464
12.9 Dual-slope AID Conversion 467
12.10 AID Accuracy and Resolution 471
Summary 472
Glossary 473
Problems 473
13. Memory
476
13.1 Basic Terms and Ideas
477
13.2 Magnetic Memory 479
13.3 Optical Memory 483
13.4 Memory Addressing 486
13.5 ROMs, PROMs, and EPROMs
491
13.6 RAMs
496
13.7 Sequential Programmable Logic Devices 503
13.8 Content Addressable Memory 506
Summary 507
Glossary 508
Problems 509
14. Digital Integrated Circuits
512
14.1 Switching Circuits 513
14.2 7400 TTL 518
14.3 TTL Parameters 520
14.4 TTL Overview 528
14.5 Open-collector Gates
530
14.6 Three-state TTL Devices
532
14.7 External Drive for TTL Loads 534
14.8 TTL Driving External Loads 537
14.9 74COO CMOS
538
14.10 CMOS Characteristics
541
14.11 TTL-to-CMOS Interface 544
14.12 CMOS-to-TTL Interface
546
14.13 Current Tracers
548
Summary 550
Glossary 551
Problems
552
Contents
15. A!)piications
558
15.l Multiplexing Displays 559
15.2 Frequency Counters 565
15.3 Time Measurement 570
15.4 Using the ADC0804
571
15.5 Microprocessor-compatible AID Converters 577
15.6 Digital Voltmeters
585
Summat)' 591
Problems
591
16. A Simple Computer Design
16.1 Building Blocks 594
16.2 Register Transfer Language 597
16.3 Execution oflnstructions, Macro and Micro Operations 599
16.4 Design of Control Unit 602
16.5 Programming Computer 605
Summary 612
Glossary 612
Problems
613
Appendix 1: Binary-Hexadecimal-Decimal Equivalents 615
Appendix 2: 2's Complement Representation
621
Appendix 3: TTL Devices
625
Appendix 4: CMOS Devices
628
Appendix 5: Codes
630
Appendix 6: BCD Codes
633
Appendix 7: Overview of IEEE Std. 91-1984, Explanation of Logic Symbols 638
Appendix 8: Pinout Diagrams 643
Appendix 9: Answers to Selected Odd-Numbered Problems 647
Index
593
672
Preface to the Seventh Edition (SIE)
The seventh edition of Digital Principles and Applications continues with the upgradation of the work started
in its previous edition. The job was to build upon the strengths of one of the best introductory and authentic
texts in the field of Digital Electronics-its lucid language, down-to-earth approach, detailed analysis and
ready-to-use information for laboratory practices. The sixth edition sought improvement primarily by (i)
strengthening the design or synthesis aspect that included advanced material, such as a simple computer
design, and (ii) incorporating many new topics like Hardware Description Language, Asynchronous
Sequential Circuit, Algorithm State Machine chart, Quine-McClusky algorithm, Look Ahead Carry Adder,
etc.
The tremendous response to the improvements made in the sixth edition from the academic community
prompted us to work on their suggestions and come out with this seventh edition.
NEW TO THIS EDITION
The seventh edition has been revised extensively and restructured to emphasize new and important concepts
in Digital Principles and Applications. This edition increases the depth and breadth of the title by incorporat-
ing latest infonnation on existing topics like BooleanAlgebra, Schmitt Trigger, 555 Timer, Edge Triggering,
Memory Cell, Computer Architecture, and also introduces new topics like Noise Margin, Error Detection and
Correction, Universal Shift Register and Content Addressable Memory.
The most notable change in this edition is the inclusion of two completely new features-problem solving
by multiple methods and laboratory experiments-that will enable the student community develop deeper
understanding of the application side of digital principles. Problem solving by multiple methods help students
in understanding and appreciating different alternatives to reach a solution, without feeling stuck at any point
of time. Laboratmy experiments facilitate experimentation with different analysis and synthesis problems
using digital integrated circuits (IC). Each experiment describes its aim, a short reference to theory, apparatus
required and different work elements.
THE BASIC FEATURES
The new edition retains its appeal as a complete self-study guide for a first-level course on Digital Logic
and Digital Circuits. It will serve the purpose of a textbook for undergraduate students of CSE, ECE, EEE,
Electronics and Instrumentation and IT. It will also be a valuable reference for students of MCA, BCA,
DOEACC 'A' Level, as well as BSc/MSc (Computer Science/IT).
Preface to the Seventh Edition (SIE)
The key features are:
>- Presence of various applications and lab experiments considering the common digital circuit design
employed in industries ( e.g., LCD display and ADC0804 operation).
>- In-depth coverage of important topics like clock and timing circuits, DIA-AID conversion, register,
counters and memory.
>- Tutorial-based approach with section-end self test questions and problem solving through various
methods.
>- Useful discussion on TTL and CMOS devices and pin diagrams
>- Rich Pedagogy
• 180 Solved Examples
• 290 Section-end Problems
• 500 Chapter-end Problems
COMPREHENSIVE WEBSITE
An important addition to this title is the accompanying website-http://www.mhhe.com/leach!dpa7, designed
to be an exhaustive Online Learning Centre (OLC). This website contains the following:
For Students
• Downloadable codes for HDL examples in the book
• Supplementary Reading material
Besides Quine-McClusky code and HDL examples, additional information and discussion on various
supplementary materials like five-variable Karnaugh Map and Petrick's Algorithm will be available here.
Regular updates on different topics of Digital Electronics will be posted to keep the reader informed about
recent changes in this field.
For Instructors
Instructors who have adopted this textbook can access a password-protected section that offers the following
resources.
• Solution manual
• Chapterwise PowerPoint slides with diagrams and notes
ACKNOWLEDGEMENTS
I would like to acknowledge the inspiration and support I received from Prof. B N Chatterji (Retd.), Prof.
RN Pal (Retd.), Prof.RV Rajakumar, Prof. A Chakraborty, Prof.PP Chakraborty, Prof. D Datta, Prof. S
Bannerjee, Prof. P K Biswas, Prof. S S Pathak, Prof. S Mukhopadhyaya, Prof. AS Dhar, Prof. I Chakraborty,
Prof. P Mandal, Prof. S Mahapatra, Prof. T K Bhattacharya, and all my faculty colleagues at Indian Institute
of Technology (IIT) Kharagapur, especially, from the Department of Electronics and Electrical Communica-
tion Engineering and GS Sanyal School of Telecommunications. But for the paucity of space, I would have
named many others.
Preface to the Seventh Edition (SIE)
Thanks are due to my research students-Mr S Ari, Mr Md Sahidullah, Mr Israj Ali, and Mr A Manda! for
their contribution at different stages of development of the edition. I acknowledge the benefit derived from
my interaction with different batches of students while teaching the Digital Electronics subject-three years
at Institute of Engineering and Management, Kolkata and over six years at IIT Kharagpur.
I am grateful to the esteemed reviewers for their encouraging comments and valuable suggestions for this
edition.
Sunil Mathur
Maharaj a Agrasen Institute of Technology, New Delhi
VKumar
Maharaj a Surajmal Institute of Technology, New Delhi
Bijoy Bandopadhyay
University College of Science & Technology, Kolkata
Anita Kanavalli
MS Ramaiah Institute of Technology, Bangalore
I also thank the entire team of Tata McGraw Hill Education, more specifically Vibha Mahajan, Shalini Jha,
Ashes Saha, Surbhi Suman, Anjali Razdan and Baldev Raj for their support.
At this point, I humbly remember all my teachers and my father (late) G N Saha who provided me a great
learning environment. I also fondly recollect the contributions in my upbringing ofKharagpur Vivekananda
Yuva Mahamandal, Vivekananda Study Circle, IIT Kharagpur Campus and Ramakrishna Mission. I must
mention the support I always received from my family-my mother, my parents-in-law, my sisters (specially
Chhordi), Chhoto Jamaibabu, and last but not the least, my wife, Sanghita, and daughter, Upasana. The effort
behind this work was mine but the time was all theirs.
GOUTAM SAHA
Feedback
Due care has been taken to avoid any mistake in the print edition as well as in the OLC. However, any note
on oversight as well as suggestions for further improvement sent at
