EBG Structures Research For The Application Of The Power Distribution Network In The High-speed PCB

The electromagnetic bandgap (EBG) structures for the noise suppression of thepower distribution network (PDN) in the high-speed printed circuit board (PCB) arestudied in this paper. The basic components, the models and the origins of thesimultaneous switching noise (SSN) are firstly introduced. Then the mushroom-likeEBG structures based on the high impedance surface (HIS) and the coplanar EBGstructures are investigated, including the pespectives of the design concept, thecharacters of the stopband and the equivalent circuits of these two EBG structures. Atthe same time, two methods for enhancing the SSN mitigation of the EBG structures arepresented according to the equivalent models. Finally, three novel EBG structures areproposed according to the theory of the EBG structures described above. The newstructures are efficiently employed to mitigate the SSN of the PDN in the high-speedPCB. The detailed contents are illustrated as follows:(1) A wideband EBG structure based on the HIS is proposed. The capacitancebetween the power plane and the patch can be increased and the inductance of the patchreduced by adding a T-shaped interdigital capaictor (IDC) between the two planes.Compared with the traditional EBG, the-30dB stopband of the proposed structure isbroadend from6.1GHz to7.1GHz and the lower corner frequency is decreased from930MHz to290MHz. In the case of increasing the number of planes in the IDC anddecreasing the thickness of the cell without changing the area of the EBG unit, theexcellent continuous wideband SSN is verified by the simulation.(2) A multilayer EBG structure with two embedded spiral-shaped planes betweenthe power plane and the typical mushroom-like EBG structure is presented, in which theequivalent capacitance between the power plane and the HIS and self-inductance of thepatch can be increased significantly, while the self-inductance of the power planedecreased. The proposed EBG structure performs excellent ultra wideband SSNmitigation in the high-speed PCB. The-30dB suppression bandgap of the new design isfrom0.6GHz to15GHz. The good performance is validated by the simulation.(3) A stopband-enhanced coplanar EBG structure is proposed, of which the unitcell is consisted of a metallic patch and four spiral-shaped bridges. This design candecrease the lower corner frequency and increase the bandwidth with keeping the signalintegrity. The-29dB stopband is from200MHz to5.8GHz with the bandwidth5.6GHz. A2-Dimension equivalent model, which is validated by the simulation, is presentedsimultaneously for the purpose of predicting the parameters of the stopband.