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The electromagnetic radiation from a modules-on-backplane configuration found in computers is analyzed by means of the finite-difference time-domain (FD-TD) technique. The issues pertaining to the effects of the modules in influencing the overall radiating capacity of the configuration are addressed. Analyses are facilitated by using simplified modules-on-backplane models and by using a voltage source as the source of electromagnetic energy at a connector between a module and the backplane. The potential for enhancement of spurious emissions by the module-on-backplane configuration is demonstrated. For modules of typical dimensions, resonance is observed at the hundreds of MHz frequency range. Comparisons between numerical predictions and measurements are conducted to validate the numerical method.

The electromagnetic coupling between two adjacent vias in a multilayered integrated circuit is analyzed by means of equivalent magnetic frill array models incorporated with the even- and odd-mode approach. Closed-form expressions for the coupled noise on the passive via are derived. The coupling responses in the frequency domain and crosstalk waveforms in the time domain for some multilayered via structures are calculated based on these formulas. A 4-layer experimental model is constructed and measurements are taken for the transmission, reflection, and coupling responses. The measurements show good agreement with the calculated results over a frequency range of up to 18 GHz.

The electromagnetic radiation from a VLSI chip package and heatsink structure is analyzed by means of the finite-difference time-domain (FDTD) technique. The dimensions of a typical configuration calls for a multizone gridding scheme in the FDTD algorithm to accommodate fine grid cells in the vicinity of the heatsink and package cavity and sparse gridding in the remainder of the computational domain. The issues pertaining to the effects of the heatsink in influencing the overall radiating capacity of the configuration are addressed. Analyses are facilitated by using simplified heatsink models and by using dipole elements as sources of electromagnetic energy to model the VLSI chip. The potential for enhancement of spurious emissions by the heatsink structure is illustrated. For heatsinks of typical dimensions, resonance is possible within the low gigahertz frequency range. The exploitation of the heatsink as an emissions shield by appropriate implementation schemes is discussed and evaluated.

An analysis of multilayer tape automated bonding packages uses equivalent circuits as coupled transmission lines involving complementary metal oxide semiconductor integrated circuits. Results conform well with theoretical predictions such as the reduction of signal-to-reference ratio to upgrade electrical performance and better performance of short tapes in comparison with longer tapes. Results also show that signal edges and reference system stabilization is improved with the proper discrete bypass capacitance.