Excerpts

Current and past users of Introductory Circuit Analysis (ICA), now in its tenth edition, have a right to wonder why I have chosen to write another text on essentially the same subject matter. The reason lies in my belief that there has been a growing need in recent years for a text dedicated primarily to those concepts that a graduate of this program of study must retain in order to be successful in the industrial community. In other words, a text is needed that has an increased measure of detail in specific important areas to ensure a clear, correct understanding of the most important laws and concepts, with less concern for special cases and material of less importance. The goal has been to create a text with a more practical orientation to better prepare the student for the laboratory and real-world experience. Admittedly, in comparing the tables of contents of the two texts, one can immediately see that there is a close correspondence in content (although numerous sections are moved and a number of chapters are combined). This correspondence, however, should not suggest that this text is merely a cut-and-paste revision of the ICA text. In fact, as I worked through the copyedited pages of this new text, I realized how little of the original ICA presentation remains. Except for the practical examples and the computer coverage, the books are very different. If you examine any section of particular interest, you will find that the pace, level of presentation, and content of Essentials of Circuit Analysis are all different from those of the ICA text. From the very beginning, I decided that any cut-and-paste approach simply would not work. I examined each topic, decided what was really important, and wrote the corresponding sections in almost exactly the same way that I might teach the subject in the classroom. I believe that the differences between ICA and this text are evident immediately in just leafing through the pages. Essentials of Circuit Analysis truly has an exciting new appearance that invites examination and further investigation. This text includes the actual construction of numerous networks to help define how a circuit diagram is drawn. Meters are also included throughout the text to maintain a close link with real-world experience. Methods of analysis are simplified by removing concern about special cases. Controlled sources are not included, while subjects such as Bode plots are included but are only touched upon rather than covered in depth. Theorems such as the substitution theorem, Millman's theorem, and the reciprocity theorem are eliminated in favor of giving more coverage to more important concepts. As a developmental aid, a list of objectives is introduced at the beginning of each chapter, and a chapter summary list and an equation list are added to the end of each chapter. The format of the text is designed to ensure that students are aware of the concepts they should take away from the course. All of the artwork utilizes color and shading to clarify the analysis being described, and many new photos are added. Each problem section is written to complement the content and level of coverage presented, progressing from the simple to the complex within each section, with emphasis on developing a student's confidence before moving on to the more complex problems. FEATURES Important changes in content begin in Chapter 1 and progress throughout the entire text. Chapter 1 includes expanded coverage of the proper use of calculators. As confident as students might appear in their use of the calculator, they continue to generate impossible results because they do not know the correct operating sequences. Section 1.12 describes in detail the specifications provided with a computer. This general information about a computer system is provided so that users of a computer can understand its capabilities and its limitations. Throughout the introductory chapters, new sections are added and older ones are deleted. The ampere-hour rating of a battery has its own section (Section 2.6), and a section is added (Section 2.7) to cover factors that affect the life of a battery. The coverage of voltage and current (Sections 2.3 and 2.4, respectively) are reversed to emphasize that it is the voltage that initiates the flow of charge in an electrical system, not vice versa. The use of the metric system to calculate body resistance is not included in this text in order to provide more coverage of the circular mil approach. A number of derivations are eliminated in favor of spending more time helping the student understand the conclusions and apply the resulting equations. Film resistors, rather than carbon composition resistors, are used throughout the text to reflect recent trends. Instrumentation appears as often as possible to prepare the student for both real-world and laboratory experiences. Analogies are also used whenever possible to clarify important concepts. To ensure that students understand the process of creating network diagrams, the first few diagrams are derived from a drawing of the wired network. Ammeters and voltmeters are also applied to a drawing of the actual wired network to ensure a proper understanding of the use of these basic instruments. Too often, students simply apply the meters to a line drawing, and confusion and misunderstanding result. In many ways, I feel that the chapters on series and parallel networks (Chapters 5 and 6, respectively) are two of the most important chapters because they expose the student to a number of the fundamental laws of electric circuits. These laws are carried throughout the remaining chapters of the text, and thus expanded coverage of each concept is provided through analogies, wired circuits, examples--whatever it takes to give the student a solid understanding of the principles involved. Chapter 6 on parallel networks is covered from a purely resistance viewpoint rather than emphasizing conductance levels. The use of conductance levels is covered in a later chapter, but early descriptions using the resistance approach are more in line with what I would normally cover in an actual lecture on the subject. In the same light, the chapter on series-parallel circuits (Chapter 7) also receives special attention because it provides a test of the concepts just learned in the previous two chapters. Single- and double-subscript notation is covered in detail but is relegated to a later section to be sure that the introductory sections are not clouded by this special notation. Every effort is made to ensure that the methods of analysis (Chapter 8) initially appear friendly and less complex. The number of steps to apply each method is reduced, and the details associated with special cases are in a later section in Chapter 8. Each step in the application of each method is covered in detail, and the example problems are in line with the needs of the student. The concepts of supermesh and supernodes are placed in a later section to avoid unnecessary complexity in the early stages of development. An approximate method developed by this author is also introduced to provide an alternative to the more complex supermesh and supernode approaches. In the theorem chapter (Chapter 9), the examples associated with the superposition theorem and Thevenin's theorem are carefully chosen to match the needs of the student, and thus these examples are not overly complex. The topic of maximum power transfer is treated in a simple manner, and topics of lesser importance have reduced coverage. Experimental techniques are discussed in detail to prepare the student for the laboratory experience. Norton's theorem is included because it provides an excellent opportunity to test the student's knowledge of current sources and the impact of a short circuit in a network. The chapters on capacitors and inductors, (Chapters 10 and 11, respectively) use a less mathematical approach. These chapters have extended coverage of the fundamental behavior of each component, the transient response, calculator usage, reading the nameplate data on the unit, and associated instrumentation. The general equation for the transient behavior of each component with initial conditions is developed at an early stage to provide a general equation for the discussions and examples to follow. Current and past users of the ICA text will find that the chapter on magnetic circuits is not included here. Many of the important topics covered in that chapter are now scattered throughout this text, but in less depth. The content of the first chapter on the ac response (Chapter 12) is very similar to that of the ICA text, but you will find extended coverage of instrumentation and the use of the calculator. Further, in deference to industry usage, the subscript "rms" rather than the subscript "eff" is now used throughout. The following ac chapter (Chapter 13) represents a major change in pedagogy, with a beginning section devoted to adding and subtracting sinusoidal waveforms rather than a somewhat complex discussion of derivatives. The result is a more natural flow from the previous chapter. In addition, the student avoids a complex topic so early in the introduction to ac waveforms. Phasors are then introduced and applied to the basic elements. The entire discussion of the response of the capacitor and inductor to an ac signal is written using a less mathematical approach, with general statements that should be helpful to a student whenever working with capacitors or inductors. Although there is no power chapter in this text, the important concepts concerning power are introduced as needed in the ac section. Furthermore, the frequency response of the basic elements is treated at two levels--the ideal and the practical--with more general comments and less mathematics. The basic chapter on series and parallel ac networks (Chapter 14) is written with more detail and with less dependence on letting the mathematics generate the solution. The approach to the frequency response of each configuration includes enhanced artwork and an expanded commentary rather than leaning on a purely mathematical derivation of the results. Parallel ac networks are treated in the same manner as appearing in the do section, in order to build student confidence through repetition and to demonstrate the similarities that exist between solutions in the ac and do domains. Phase measurements are covered in detail in Chapter 14 rather than interspersed throughout the ac chapters. The content of the chapter on series-parallel ac networks (Chapter 15) is very similar to that in the ICA text, except that the power triangle is added here. The power triangle is an important component of any background in this field and deserves to be covered in some detail. The detail, however, is not overwhelming, with a few straightforward examples to demonstrate the important facets of the subject. The chapter on ac methods of analysis and theorems (Chapter 16) is a close match with the corresponding do chapters except for the use of phasors and impedances in the analysis rather than just fixed sources and resistors. A major difference between this text and the ICA text is that this one does not contain sections that apply the methods and theorems to networks with controlled sources. Resonance and filters are covered in a single chapter (Chapter 17) primarily because the majority of the material on Bode plots is removed. Most of the important conclusions associated with each subject are present, but derivations and special cases are avoided. The detailed discussion of decibels is included in its entirety in response to current ICA users who have found the material unique in its coverage. Transformers and three-phase systems are combined into one chapter (Chapter 18), with content limited solely to the ideal iron-core transformer. Most of the important concepts associated with each topic appear in the chapter to establish a level of understanding that should prepare a student for his/her initial exposure to both areas in an industrial environment. Excerpted from Essentials of Circuit Analysis by Robert L. Boylestad All rights reserved by the original copyright owners. Excerpts are provided for display purposes only and may not be reproduced, reprinted or distributed without the written permission of the publisher.