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Amplifiers
10.1 DEFINITIONS AND CLASSIFICATIONS
In electronics, amplication concerns the production, by means of an appropriate
circuit, of an output signal that has the same form as the input signal but with an
increased level of voltage and/or current and/or power (Figure 10.1a andb).
The input signal is provided by the signal source, and we need to amplify it
when the source available is not powerful enough to pilot a load. If we consider an
audio system, the AC signal source can be a CD or DVD player, the microphone in a
telephone handset, the antenna of a radio receiver, etc. The related voltage signal
can range between a few μV and a ...