INTRODUCTION
Passive components such as capacitors, inductors and ferrite beads are often used when designing various high frequency circuits. Unfortunately “real’ passive components have characteristics that deviate from the “ideal” response. For example, the parasitic performance of capacitors is often modeled using additional discrete components, as shown in Figure 1 [1]. By including these “extra” components EMI engineers try to account for the frequency-dependent responses of actual components when the components are subjected to electrical stresses. Equivalent circuit of a typical capacitor