Electromagnetic bandgap power/ground planes for wideband suppression of ground bounce noise and radiated emission in high-speed circuits

A power/ground planes design for efficiently eliminating the ground bounce noise (GBN) in high-speed digital circuits is proposed by using low-period coplanar electromagnetic bandgap (LPC-EBG) structure. Keeping solid for the ground plane and designing an LPC-EBG pattern on the power plane, the proposed structure omnidirectionally behaves highly efficiently in suppression of GBN (over 50 dB) within the broad-band frequency range (over 4 GHz). In addition, the proposed designs suppress radiated emission (or electromagnetic interference) caused by the GBN within the stopband. These extinctive behaviors of low radiation and broad-band suppression of the GBN is demonstrated numerically and experimentally. Good agreements are seen. The impact of the LPC-EBG power plane on the signal integrity for the signals referring to the power plane is investigated. Two possible solutions, differential signals and an embedded LPC-EBG power plane concept, are suggested and discussed to reduce the impact.

I. Introduction

With the trends of fast edge rates, high clock frequencies, and low voltage levels for the high-speed digital computer systems, the ground bounce noise (GBN) or simultaneously switching noise (SSN) on the power/ground planes is becoming one of the major challenges for designing the high-speed circuits. Because of the parallel-plate waveguide structure between power and ground planes in the advanced high-speed packages, the resonance modes of the parallel-plate waveguide can be excited by the GBN. Research has shown the resonance noise propagating between the power and ground planes could cause serious signal integrity (SI) or power integrity (PI) problems for the high-speed circuits [1]–[3]. Moreover, due to the cavity resonance effect between the power/ground planes, the GBN also results in significant radiated emissions or electromagnetic interference (EMI) issues [3].