Switching components are simple electronic switches, usually consisting of three pins, in which the presence of a voltage or current in one pin allows current to flow between the other two pins. To set the device into a state of conduction or interdiction, and therefore to conclude this procedure, the necessary transition time is very short, but not immediate. This time produces a waste of energy, called “switching loss” and is responsible for most of the losses in a conversion circuit. It occurs exactly at the intersection between the voltage signal and the current signal.

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