Impedance analyzers are essential equipment's for any engineer working in the domain of electrical circuits. The impedance of a circuit is determined by exciting this later with a sine voltage over a frequency span and by observing the current consequently flowing through it (or vice versa). The excitation level is limited to low amplitudes and in some cases, is not sufficient to reach the saturation/non-linearity zone of the circuit while it does have to be used, and therefore charactefized, in that zone. Different ways exist to expand the excitation level.