Reduction of Signal Overshoots in High-Speed Interconnects Using Adjacent Ground Tracks

Abstract

In this paper, we present a novel computational model that uses ground tracks adjacent to the interconnect line for alleviation of signal overshoots. It is found that the adjacent ground tracks increase the capacitance of the interconnect line and therefore the damping factor, which reduces the signal overshoots and undershoots to acceptable levels. The proposed model is based on the unified approach (variational analysis combined with transverse transmission line technique) and uses existing ground tracks that are commonly used for crosstalk mitigation between coupled interconnects, thus avoiding any physical changes in the interconnect geometry. Results are verified using finite-difference time-domain simulations and measurements performed on a vector network analyzer. The novelty of our model lies in the easy and efficient computation of line parameters and damping factor. The proposed model can be used for mitigation of signal overshoots in high-speed interconnects, whether on-chip, or at packaging, board, or system levels, where overshoots are a common design headache.