Analysis and characterization of package resonance

This paper presents FDTD analysis and prediction of the overall effects of the resonance in MIC and MMIC electronic packaging. Practical structures that result in strong resonance effects are investigated such as coupled cross lines with a via transition (STML - single via transition on multiple lines), and multiple via transitions on a single line (MTSL). A detailed study of the mutual coupling, including the resonance effects, has also been performed and is presented. Results of the analysis indicate that the package performance can be very sensitive to resonance effects. A broadband equivalent circuit model for multiple transition discontinuities (two via holes) on a single line has been developed and is presented. There is good agreement between the predicted frequency response of the FDTD and the circuit models over a broad band of frequencies. The analysis presented gives an insight into the limits at which coupling effects on the overall package performance can be neglected. The equivalent circuit model presented can greatly simplify the analysis and simulation of a complex package which includes several transition discontinuities, assuming that the coupling is small.