The equivalent circuit refers to a theoretical circuit that retains all electrical characteristics of a given circuit. Generally, it is the simplest form of a more complex circuit to aid analysis. The equivalent circuit of components is complex because of the existence of parasitics, but by using single frequency signal, LCR meters can only measure the value of resistance and reactance. Thus, the equivalent circuit of components can be lumped as the simplest series or parallel model that represents the resistive and reactive parts of total impedance.