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Some Applications
We have used transistors to amplify signals. This fantastic property makes
transistors suitable for a really large number of applications, and in this chapter
we focus on some of the most relevant or curious ones.
15.1 AUDIO AMPLIFIER
An audio amplier can be generally schematized with a cascade of black boxes
each representing a single stage. As an example, we can represent an audio ampli-
er with a chain of an input selection, a pre-amplier section, a voltage ampli-
er, a tone control, and a power amplier (Figure 15.1).
The input selection is necessary to establish which source provides the signal to
be amplied, and it ...