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Review of Widlar: AN-4 Monolithic Op Amp - The Universal Linear Component

Download AN-4 Monolithic Op Amp - The Universal Linear Component (pdf) from National

This 1968 Application Note by the legendary Bob Widlar contains several interesting Op Amp circuits, most of them using the LM101 Op Amp which Widlar had designed at National. There is a detailed description for each circuit. Some of the techniques he describes are still very interesting even more than 40 years later. However, many parts of the note are outdated now, for example the statement that no monolithic FET amplifiers can be produced. Such things are probably very confusing if you are new to electronics or to Op Amps. If, however, you have a solid knowledge of electronics, know a bit of its history and can recognize which statements are not true anymore today - then you can find some very interesting ideas in this Application Note.

You should also take a look at some recommendations for other Op Amp Applications.

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