Electronics: A Systems Approach [Paperback]

Features and Benefits

A wealth of computer-based exercises suitable for all circuit-simulation software packages.
Freely available online PSpice files containing numerous simulations.
A new section on programmable logic devices (PLDs).
New material on the important topic of electromagnetic compatibility.
A new section on laboratory instruments describing oscilloscopes and digital multimeters.
A new appendix covering the IEC 617 symbols for logic elements.
Even more worked examples and self-assessment exercises.

When the first edition of this book was published it represented a very novel approach to the teaching of electronics. Up to that time most texts in this area had adopted a decidedly 'bottom-up' approach to the subject. They often started by looking at semiconductor materials and worked their way through diodes, transistors and biasing, before looking at simple amplifier circuits. Eventually, several chapters later, they might actually look at the uses of the circuits being considered.

The first edition of Electronics: A Systems Approach pioneered a new approach to the teaching of electronics by explaining the uses and required characteristics of circuits before embarking on detailed analysis. This aids comprehension and makes the process of learning much more interesting. Another innovation within the first edition was that it provided a unified treatment of both analogue and digital electronics within a single volume, allowing common ground between these two areas to be developed. While many texts are still resolutely device centred, it is pleasing to see that several more enlightened authors are now following a more systems oriented approach.

One of the great misconceptions concerning this approach is that it is in some way less rigorous in its treatment of the subject. It seems that some instructors believe that any book that does not start with several pages of complex mathematics does not do justice to the teaching tradition. The systems approach does not define the depth to which a subject is studied but only the order and manner in which the material is presented. Many students will need to look in detail at the operation of electronic components and to understand the physics of its materials; however, this material will be more easily absorbed if the characteristics and uses of the components are understood first.

One of the many advantages of a systems approach is that it allows a single text to be used by a wide variety of students. All engineers and scientists should have an appreciation of the basics of electronics since it is an essential enabling technology across a broad spectrum of disciplines. Presenting the information in a 'top-down' manner makes it easier to assimilate for all readers. For the student who is destined to be an electronic specialist this route provides the information in the most accessible order, thus aiding comprehension. For the non-specialist the information is presented such that the reader may progress as far through the text, or through the various sections, as is appropriate to give the required level of detail. The text includes the circuit analysis and design techniques needed by students destined for more advanced circuit design courses. However, it is presented after a more general introduction to the topic such that non-specialists may easily skip the detail without harming their understanding of the basics.

Throughout the text parallels between analogue and digital techniques are highlighted and a systems approach to design is encouraged. Numerous examples are given to illustrate the techniques being discussed and design case studies are included at the end of each chapter to reinforce the material and to promote a systematic approach.

Who should read this book
This text is intended for undergraduate students in all fields of engineering and science. For students of electronics and related disciplines it provides a coherent set of material suitable for first level courses in analogue and digital design. For other students it includes most of the electronics material that will be required throughout their course.

New material within this edition
This second edition has given an opportunity to update the text and to take account of developments in a very rapidly changing field. It has also permitted several major revisions of the text. The major changes to the book are:

    *    The text now includes a large number of computer simulation exercises as an aid to comprehension. The exercises make use of a set of demonstration files that may be downloaded free of charge over the Internet and a software simulation package that can be obtained free of charge from its supplier.

    *    A short section on laboratory instruments has been included which describes the operation of oscilloscopes and digital multimeters.

    *    A new section has been added on electromagnetic compatibility (EMC) to reflect the growing recognition of the importance of this topic to all engineers.

    *    A substantial new section has been added on programmable logic devices (PLDs) to replace the limited treatment of array logic in the first edition.

    *    The number of worked examples within the text has been increased.

    *    Additional self assessment exercises have been added to those at the end of the chapters.

    *    A new appendix describes the IEC 617 symbols for logic elements.

    *    An appendix now gives numerical answers to many of the end of chapter exercises. If the number of the exercise is set in italic type, for example, see Exercise 1.11, on page 14, this indicates that the answer can be found in this appendix.

Circuit simulation
Throughout the book there are numerous Computer simulation exercises that support the material in the text. These are marked by a computer icon in the margin as shown on the left. The exercises may be performed using any suitable circuit simulation package, although the use of PSpice is recommended. The PSpice simulation package is produced and marketed by the MicroSim Corporation and is one of the most widely used packages both within industry and within Universities and Colleges. PSpice is based on the industry standard SPICE simulation package and comes with a suite of programmes allowing the schematic capture of circuits and the graphical display of simulation results.

MicroSim produce a free evaluation version of the software which incorporates most of the important features of the package but is restricted in the complexity of the circuits that may be simulated. This evaluation version is completely adequate for the needs of this text. Readers with their own computer may obtain a free copy of the software by contacting MicroSim at their website on the Internet.Those making use of a computer within a University or College should check with the system manager to see if PSpice is already available. If not, they should request that it be loaded.

Since the main purpose of this text is to teach electronics rather than simulation, the text does not attempt to teach the use of PSpice or any other simulation package. Most electronics programmes now include a course on computer simulation that looks at the modelling methods used and considers the limitations and restrictions of these tools. Such courses are not normally taken by non-electronics students. I believe that all students can benefit from the use of simulation when studying electronics since it gives a very graphic insight into the operation and characteristics of circuits. Fortunately, the skills required to perform simple simulations can be learnt in a few minutes and I would suggest that all readers of this text should take advantage of these powerful packages. Indeed, it may be beneficial for electronics students to gain an insight into the use of simulation by using it at a basic level with this text before taking a more detailed simulation course.

One of the barriers to the use of simulation in the study of electronics is the time taken to prepare the circuit files required by the simulator. Even though packages such as PSpice permit circuits to be entered in a straightforward way through the use of a schematics capture package, it can take several minutes for even a simple circuit to be entered (particularly for the inexperienced). In order to speed up the use of simulation, and to encourage readers to make maximum use of these powerful tools, a suite of demonstration files is available to complement this book. The presence of the demonstration files means that it is possible to simulate the various circuits without a detailed knowledge of the simulation package being used. All that is required is the ability to load a file, run the simulation and make minor modifications to the circuit. Such skills could be gained from a short demonstration within a laboratory session, or could be obtained in a few minutes by referring to one of the many excellent texts available on this topic (those using PSpice can find a list of books on this package on the MicroSim website).

Each demonstration file is provided in two formats: firstly as a net list and secondly as a PSpice schematics file. The first of these formats is compatible with all versions of SPICE and allows the demonstration files to be used with a wide variety of simulation packages. Unfortunately, while this format is compatible with a range of simulators it describes only the components of a circuit and their connectivity. This information is all that is required to simulate a circuit, but does not allow the circuit diagram to be drawn. This makes the files difficult to interpret and does not aid comprehension. For this reason the demonstration circuits are also provided in the form of PSpice schematics files. These can be read by the PSpice schematics editor which displays the circuits and allows them to be easily modified. The schematics package provides a user friendly interface to the PSpice simulator and greatly aids comprehension of the circuits being studied. For this reason the reader is encouraged to take advantage of the free PSpice software described above, to gain maximum benefit from the various demonstration files.

The names of the demonstration files associated with the computer simulation exercises are given under the computer icons in the margin. An example is shown on the left. Icons will also be found alongside many of the diagrams within the text indicating that simulation files are also available for these circuits to simplify their study using simulation. Associated with the demonstration files is a README file that contains configuration information for each simulation. This document, which assumes the use of PSpice, explains how to configure the simulation package for each circuit.These exercises do not have demonstration files and are set to test the reader's understanding of the use of simulation as well as the circuits concerned.

Assumed knowledge
Throughout the book it is assumed that the reader has an understanding of basic passive components such as resistors and capacitors and their parallel and series combinations. A knowledge of the AC behaviour of these components is also assumed.

To the instructor
A comprehensive instructorÎs guide is available for this text. This gives guidance on course preparation and suggests how material might be selected to meet the needs of students with different backgrounds and interests. The guide also gives fully worked solutions to all the numerical exercises within the text and sample answers for the non-numerical exercises. Instructors adopting this book as a course text should contact their local Addison Wesley Longman representative to obtain a complimentary copy of this guide.

Acknowledgements
I would like to express my gratitude to several people who have provided help and support during the production of this text. In particular I would like to thank my colleagues at the University of Warwick who have provided useful feedback on the first edition and David Dyer for his comments on the first draft of the new material on PLDs.

I would also like to thank the companies who have given permission to reproduce their material. These are: RS Components Limited for the photographs of Figures 2.1, 2.2, 2.4, 2.6(b) and 2.12; Farnell Electronic Components Limited for the photographs of Figures 2.3, 2.14(a) and 2.15; R. D. P. Electronics Limited for the photograph of Figure 2.7(b); Tektronix U.K. Limited for the photograph of Figure 2.18(a); Fluke Corporation for the photograph of Figure 2.19(a); Texas Instruments for the diagram at the end of the Design Study in Chapter 8 and Figures 11.20 and 11.32; and Advanced Micro Devices Inc for the diagrams of Figures 11.47, 11.48 and 11.49.

Finally, I wish to give special thanks to my family for their help and support during the writing of this book. In particular I wish to thank my wife Jill for her constant encouragement and understanding.