Guide to Linear Analog Circuits--Article Index

TABLE OF CONTENTS:

GENERAL ANALOG CIRCUIT DESIGN

Test your analog-design IQ

Use comparator ICs in new and useful ways

AUDIO

Use off-the-shelf linear ICs for audio designs

CONTROL

Analog design techniques suit process-control needs

Sample-and-hold techniques for design solutions

Current-source alternatives increase design flexibility

Designer's Guide to: Temperature control

Employ pulse-width modulators in a wide range of controllers

Expand linear circuit functions with nonlinear design schemes

Exploit D/A converters in unusual controller designs

ISOLATION TECHNIQUES

Piezo-ceramics plus fiber optics boost isolation voltages

Transformers and optocouplers implement isolation techniques

SENSING

Designer's Guide to: Temperature sensing

Exotic-transducer interfacing calls for proven techniques

Increase your design options with analog-MUX ICs

Interface nonstandard sensors using standard circuit methods

SIGNAL CONVERSION

Conversion techniques adapt voltages to your needs

Heavy-duty power supply regulates either voltage, current or power

High-powered booster circuits enhance op-amp output

Low-cost, linear A/D conversion uses single-slope techniques

SIGNAL SOURCES

Some proven techniques ease sine-wave-generator design

Low-cost dual, quad FET op-amps implement complex functions

TEST AND MEASUREMENT

6-IC circuit gauges relative humidity

Designer's Guide to: Temperature measurement

Low-cost instrument measures 4-decade power

Analog design is not dead. Neither is interest in it. Although digital design techniques have become the primary focus of most electronics trade journals and design magazines, the need for linear applications material remains strong. Designers continue to make significant advances in linear ICs, and using these new devices is anything but a trivial task.

INTRODUCTION by the AUTHOR

Writing about applications, like all engineering tasks, involves compromises and limitations. An author must, for example, consider the editorial standards of the publication he writes for, his readers' interests, his employer's commercial aspirations, and the time available. And then, the author must simply desire to do the work. Without this drive, there's no point in even starting.

Balancing these sometimes conflicting considerations can be difficult, but not unduly so. You can, for example, balance a publication's needs, its readers' interests, and your employer's needs. After all, a successful publication must reflect its readers' interests. An astute employer will understand that serving the readers' interests can benefit the company as well. Such an employer realizes that the true value of publishing an applications article can't be measured in the immediate sales the article generates.

Instead, a stream of useful articles sponsored by a certain company lets readers know that the company can provide solutions to engineering problems. Such articles are a subtle and effective form of advertising. Instead of generating immediate sales, applications articles establish credibility. They become powerful long-term sales tools because they win customers' confidence by portraying the company as a problem-solving ally.

Of course, producing an applications article takes a lot of time. Typically, I need more than 100 hours to complete each article, and some articles take 200 to 300 hours. The actual writing takes up less than 10% of all the time I spend developing an article. The bulk of my article-development time is consumed by the lab work that I write the article around.

Because engineers are basically skeptical, a good author must address them in the language of working circuits and systems: The author must use laboratory-based material that's worked out and documented. Also, it's important to know when to stop. The author should work out his material well, but he doesn't have to refine it to the highest possible degree. An article's primary function is to be a catalyst-to start the reader thinking.

Finally, an author must simply desire to do the work. Applications work allows more freedom and flexibility than almost any other engineering job. And conceiving ideas and developing them into circuits is an enjoyable way to spend one's time.

Doing applications work has allowed my hobby and my vocation to become an indivisible entity, hopefully to the benefit the reader. This state of affairs is made possible by your requests -- I appreciate your support.