Page 13 - Op Amps Design, Applications, and Troubleshooting

xii Preface

The majority of this text treats the op amp as a quasi-ideal device. That is,
only the nonideal parameters that have a significant impact on a particular design
are considered. Chapter 10 offers a more thorough discussion of nonideal behav-
ior and includes both AC and DC considerations.
The analytical and design methods provided in the text are not limited to a
particular op amp. The standard 741 and its higher-performance companion, the
MC1741SC, are frequently used as example devices because they are still used in
major electronics schools. However, the equations and methodologies directly
extend to newer, more advanced devices. In fact, because newer devices typically
perform closer to the ideal op amp, the equations and methods frequently work
even better for the newer op amps. To provide a perspective regarding the range of
op amp performance that is available, Chapter 11 includes a comparison between a
general-purpose op amp and a hybrid op amp, which has for example, a 5500
volts-per-microsecond slew rate as compared to the 0.5 volts-per-microsecond slew
rate often found in general-purpose devices.
Every circuit in every circuits chapter has been constructed and tested in the
laboratory. In the case of circuit design examples, the actual performance of the
circuit was captured in the form of oscilloscope plots. The following test equip-
ment was used to measure circuit performance:

1. Hewlett-Packard Model 8116A Pulse/Function Generator
2. Hewlett-Packard Model 54501A Digitizing Oscilloscope
3. Hewlett-Packard Think Jet Plotter
4. Heath Model 2718 Triple Output Power Supply

Items 1 to 3 were provided courtesy of Hewlett-Packard. This equipment
delivered exceptional ease of use and accuracy of measurement, and produced a
camera-ready plotter output of the scope displays. The oscilloscope plots pre-
sented in the text are unedited and represent the actual circuit performances, thus
alleviating the confusion that is frequently encountered when the ideal waveform
drawings typically presented in textbooks are contrasted with the actual results in
the laboratory. Any deviations from the ideal that would have been masked by an
artist's ideal drawings are there for your examination in the actual oscilloscope
plots presented throughout this book.
Although this text is appropriate for use in a resident electronics school, the
consistent and independent nature of the discussions for each circuit make it
equally appropriate as a reference manual or handbook for working engineers and
technicians.
So what is considered to be a satisfactory degree of accuracy in this text? On the
basis of more than 20 years of experience as a technician, an engineer, and a class-
room instructor, it is apparent to the author that most practical designs require
tweaking in the laboratory before a final design evolves. That is, the engineer can
design a circuit using the most appropriate models and the most extensive analysis,
but the exact performance is rarely witnessed the first time the circuit is constructed.
Rather, the paper design generally puts us close to the desired performance. Actual
measurements on the circuit in a laboratory environment will men allow optimiza-
tion of component values. The methods presented in this text, then, will produce