Ten Essential Skills for Electrical Engineers

Presents an uncommonly insightful perspective of the insights, experience, and wisdom of the author regarding the craft of electrical engineering. This book is a must have on the bookshelf of any newly practicing hardware engineer and those who mentor them.
Roger Colbath, Engineering Director, ViaSat, Inc.

In today s competitive marketplace, engineering students and professionals need every advantage to succeed in job interviews and in the industry. This insightful book will serve as a valuable reference for them throughout the interview process and while on the job.

Ten Essential Skills for Electrical Engineers applies the fundamentals learned in school to the practical tasks required by employers. With the ultimate goal of helping readers land a job and succeed at it, the book offers insightful chapters that teach them how to: design resistive circuits; prevent thermal failures; analyze circuits; use statistics to design manufacturable products; design feedback control systems; design op–amp circuits; design analog and digital filters; and work with high–frequency digital and RF signals.

Written in an intuitive, easy–to–follow style, the book:

Enables recent graduates in engineering to succeed in challenging technical interviews Reviews practical skills using the latest tools and techniques Focuses on the intersection between company–specific knowledge and engineering fundamentals Offers real–life, industry case studies, examples, and commentary from employers and practicing engineers Provides a companion website containing interview practice problems and advanced material for readers seeking additional expertise

Ten Essential Skills for Electrical Engineers is a must–have book for aspiring and current engineers who wish to approach their next job interview confident in their grasp of the engineering skills that employers are seeking.

Preface xi

Acknowledgments xiii

About the Author xv

About the Reviewers xvii

Note to Instructors xxi

1 HOW TO DESIGN RESISTIVE CIRCUITS 1

1.1 Design of a Resistive Thevenin Source 2

1.2 Design of a Coupling Circuit 4

1.3 Design of a Pi Attenuator 8

Problems 14

References 17

2 HOW TO PREVENT A POWER TRANSISTOR FROM OVERHEATING19

2.1 Electrical Model for Heat Transfer 20

2.2 Using Manufacturer s Data for Thermal Analysis 23

2.3 Forced–Air Cooling 26

2.4 Dynamic Response of a Thermal System 27

Problems 30

Reference 32

3 HOW TO ANALYZE A CIRCUIT 33

3.1 Frequency Response of a Transfer Function 34

3.2 Frequency Response and Impedance of Simple Circuits 38

3.3 Frequency Response for Ladder Networks 51

3.4 Generalized Technique for Determining Frequency Response54

Problems 58

References 60

4 HOW TO USE STATISTICS TO ENSURE A MANUFACTURABLE DESIGN61

4.1 Independent Component Failures 62

4.2 Using the Gaussian Distribution 63

4.3 Setting a Manufacturing Test Limit 68

4.4 Procuring a Custom Component 71

Problems 76

References 77

5 HOW TO DESIGN A FEEDBACK CONTROL SYSTEM 79

5.1 Intuitive Description of a Control System 80

5.2 Review of Control System Operation 81

5.3 Performance of Control Systems 84

5.4 First–Order Control System Design 84

5.5 Second–Order Control System Design 88

5.6 Circuit Realization of a Second–Order Control System 94

5.7 First–Order Discrete Control System 95

Problems 101

References 102

6 HOW TO WORK WITH OP–AMP CIRCUITS 103

6.1 The Ideal Op–Amp 104

6.2 Practical Op–Amps 108

6.2.1 Effect of Input Offset Voltage 108

6.2.2 Noise Contribution from Op–Amp Circuits 110

6.2.3 Dynamic Characteristics of Op–Amp Circuits 113

6.2.4 Effect of Capacitive Loading 116

6.2.5 A Nagging Issue 118

Problems 119

References 121

7 HOW TO DESIGN ANALOG FILTERS 123

7.1 Passive Versus Active Filters 124

7.2 The Lowpass RC Filter 125

7.3 Filter Response Characteristics 129

7.4 Specification of Filter Type 131

7.5 Generalized Filter Design Procedure 132

7.6 Design of Active Lowpass Filters 136

7.7 Design of Passive RF Filters 139

Problems 146

References 148

8 HOW TO DESIGN DIGITAL FILTERS 149

8.1 Review of Sampling 150

8.2 Using the z–Transform to Determine the Transfer Function andFrequency Response of Digital Filters 155

8.3 FIR and IIR Digital Filters 161

8.3.1 FIR Filters 162

8.3.2 IIR Filters 165

8.3.3 Comparisons between FIR and IIR Filters 167

8.4 Design of Simple and Practical Digital Filters 168

8.4.1 Averaging Lowpass FIR Filter 168

8.4.2 Lowpass FIR/IIR Filter 171

Problems 177

References 181

9 HOW TO WORK WITH RF SIGNALS 183

9.1 Energy Transfer 185

9.2 Signal Reflections 187

9.3 Effect of Signal Reflections on Digital Signals 190

9.4 Effect of Signal Reflections on Narrowband Signals 195

9.5 The Smith Chart 198

9.6 Using the Smith Chart to Display Impedance Versus Frequency205

9.7 Final Comments Regarding the Smith Chart 205

Problems 206

References 209

10 GETTING A JOB KEEPING A JOB ENJOYING YOUR WORK211

10.1 Getting a Job 212

10.1.1 Getting an Interview 214

10.1.2 Preparing for an Interview 216

10.1.3 The Interview 217

10.1.4 Selecting the Right Offer 220

10.2 Keeping a Job 221

10.2.1 The First Year 221

10.2.2 After the First Year 224

10.3 Enjoying Your Work 227

Afterword 231

Answers to Problems 233

Index 243

BARRY L. DORR, PE, is a Principal Design Engineer at Datron World Communications. He has taught Circuit Analysis at San Diego State University, Servo Systems for the IEEE, and numerous industrial seminars. He holds eight patents for signal processing and communication devices, and has contributed articles to Embedded Computing Magazine, Electronic Design News, and various trade publications.