The analysis using the approximate hybrid equivalent for the common-emitter and common-base configurations is very similar to that just performed using the \(r_e\) model.

The resulting equivalent is quite similar to the general structure of the common-base and common-emitter equivalent circuits obtained with the \(r_e\) model.

The \(r_e\) model has the advantage that the parameters are defined by the actual operating conditions, whereas the parameters of the hybrid equivalent circuit are defined in general terms for any operating conditions.

The \(r_e\) model suffers from the fact that parameters such as the output impedance and the feedback elements are not available, whereas the hybrid parameters provide the entire set on the specification sheet.