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Book Review: Digital Instrumentation

Digital Instrumentation: A. J. BOUWENS (McGraw Hill, 1984, 339 pp., £26.75 hardback) There are many books on the techniques of digital electronics and the associated logic, but this book is probably the only one which deals with these topics and then goes on to apply them exclusively to basic digital measuring instruments and digital measurement techniques. The book is based on a digital instrumentation course which was given to Philips Test and Measuring Instrument Sales Engineers so that, in essence, it has been 'tested (and developed) in the field'. It will, however, prove to be extremely useful to lecturers and students of digital techniques and digital instrumentation at all levels, because each of the 19 chapters is followed by a number of questions whose answers are discussed at the back of the book. The book contains 19 chapters divided up into 3 Parts as follows:Part I: Basic Binary Theory and Logic Circuits ( 8 chapters) covers the usual topics of number systems; Boolean algebra; logic gates; combinational logic; sequential logic; counters (flip-flop circuitry), scalers and shift registers; logic circuitry; interfaces and converters. This part would give general coverage for any digital electronics course, although some of the logic symbols might not be the preferred ones. Part 2: Digital Counters and 11mers ( 4 chapters) covers basic counter-circuitry; modes of operation of counters; plug-in units and special-function units (such as those for low-frequency measurements with high resolution and high-frequency measurements up to 30 GHz); instrument accuracy and measurement errors. Part 3: Digital Voltmeters and Multimeters (7 chapters) covers operational amplifiers; analogue-todigital converters; automatic operations within digital voltmeters; digital multimeters; voltmeter accuracy; guarding techniques and a.c. measurements. There is a useful Appendix (15 pages) on the programmable-bus control of laboratory equipment, with particular reference to the GPIB (IEC 625/IEEE-488) system for the interconnecting, programming and controlling of programmable laboratory-equipment in automatic-test (ATE) systems. There follows a useful 7-page glossary of terms and the answers to Questions. There is an extensive index. The author is to be congratulated on the presentation and content of this book and it can be recommended to engineers, lecturers and students alike. Minor criticisms are that there are no references and, unfortunately, the book would be too expensive for academic-course adoption. A paperback edition would, no doubt, overcome this disadvantage. BRIAN M. SHAW, Division of Electrical and Electronic Engineering, The Hatfield Polytechnic