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Class B Amplifier Distortion Summary

What is the primary source of distortion with a Class B amplifier? What are some ways the distortion can be minimized and discuss the trade offs that exist when implementing these distortion minimizing methods?

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Please see attachment for diagrams

Crossover Distortion is the most common form of distortion in Class B type Amplifiers and occurs at the point of cross over of push pull NPN, PNP transistor arrangements. The simple push pull Class B arrangement below illustrates the point well.

When the input is zero neither of the base emitter bias for both transistors are biased for conditions for conduction to occur (this is when for NPN transistors, for PNP transistors then no significant conduction occurs). The output in such cases remains essentially at zero. As the input bias rises slightly above zero, but still remains below +0.65V, the NPN transistor stays "off" and the output remains very nearly at zero (apart from some very small conduction below the knee of the NPN input/output characteristic which results in a ...

Solution Summary

A brief outline of the main cause and effects for distortion in Class B Type amplifiers and the main ways to reduce such affects