The switching of the output stage

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switching when the inductor can discharge; while the switching looks "delayed" if the output

transition tends to initiate a charging phase (see Figure 9). With a load almost free from

parasitic elements, the waveforms resemble the ones of the purely resistive cases.

With a real, more composite load, the effect of the inductive kick in comparison to the

resistive load, would be more apparent.

With a capacitor and a resistor in parallel as a load, another type of waveform can be seen

(reported in Figure 10).

As long as the output stage stays in the transient high impedance state, the output voltage

will follow the classic exponential law of an RC relaxation.

As soon as the other transistor is switched on and takes charge, the waveform is quickly

forcibly brought to its steady state value.

From the above it is possible to see how the switching times, inherently very fast, of the

output stages, may be difficult to identify in a waveform if the output load is not accurately

taken into consideration.

Figure 11 show typical switching waveform for inputs and outputs.

Figure 7.