Feedback is an integral part of our lives. Try touching your fingertips together with your eyes closed; you may not succeed the first time because you have broken a feedback loop that ordinarily “regulates” your motions. The regulatory role of feedback manifests itself in biological, mechanical, and electronic systems, al lowing precise realization of “functions.” For example, an amplifier targeting a precise gain of 2.00 is designed much more easily with feedback than without.

This chapter deals with the fundamentals of (negative) feedback and its application to electronic circuits. The outline is shown below.



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