The following article contains detail description and introduction to Power Amplifier Classification Circuit Diagram. The main characteristics of an amplifier are Linearity, efficiency, output power, and signal gain. In general, there is a trade off between these characteristics. Higher efficiency leads to extended battery life, and this is especially important in the realization of small, portable products. Power amplifiers dissipate power and generate heat, which has to be removed. Due to the small size of integrated circuits, this is a challenging exercise in design and packaging. Several recent overview presentations have highlighted the special problems with achieving high efficiency and linearity in fully integrated power amplifiers.
Power amplifiers are grouped into classes depending on the nature of their voltage and current waveforms. The first major classes to be considered are class A, B, D, E, F, and G amplifiers. The class-A amplifier has the highest linearity over the other classes. It operates in a linear portion of its characteristic; it is equivalent to a current source.
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