Research On Propagation And Suppression Of SSN For Power Distribution Network In High-Speed PCB

With the improvement of semiconductor manufacturing process,high-speed circuits are developing rapidly in the direction of multi-function,high density,low power consumption,high performance and miniaturization.However,the high integration of the circuit will bring more severe simultaneously switching noise(SSN).Since the power distribution network of high-speed PCBs usually appears as a pair of parallel copper plates(namely power and ground planes),the parallel plate pairs form a resonant cavity and the resonance can be excited by the high-frequency harmonic components of the SSN,which will cause serious signal integrity and electromagnetic interference problems in high-speed circuits and when the electromagnetic radiation radiated outward can be further coupled to the interconnection and may cause misjudgment of the chip and induce the system to not work properly.Therefore,the suppression of SSN between power distribution networks in high-speed digital system will become one of the most challenging topics in modern high-speed circuit design.A Photonic Crystal(PBG)structure refers to a periodic structure in which a dielectric material is periodically arranged in another dielectric material to block the propagation of light waves in a specific frequency band.The photonic band gap structure in the microwave band is called an Electromagnetic Bandgap(EBG)structure.Due to the superior forbidden band characteristics of suppressing SSN by using the EBG structures,this paper systematically studies the suppression of SSN between power distribution network in high-speed PCB by using dielectric EBG.structures.The conclusions obtained in this paper can be directly used in the design and analysis of power distribution networks for high-speed digital systems.This paper consists of five chapters.The contents of each chapter can be written independently,and they are closely connected and progressive,forming a complete system.The main research work and innovations of this paper are summarized as follows:1)The electromagnetic finite element method was used to establish a 2-D finite element model for suppressing SSN propagation between power/ground planes in high-speed PCBs by using dielectric EBG structures.This model transforms the 3-D problem of SSN between power/ground planes into 2-D problem for increasing the computational efficiency.The 2-D numerical calculation results were verified by the 3-D full-wave electromagnetic simulation software HFSS.The simulation results are in good agreement with the numerical calculation results to verify the correctness of the 2-D numerical algorithm.The relative dielectric constant,dielectric column size and the noise suppression bandwidth of the dielectric EBG structural unit were analyzed.The relationship between the noise suppression bandwidth and the lattice parameters of different elements was obtained.To verify that the introduction of dielectric EBG structures between the power/ground planes maintains better signal transmission quality while suppressing SSN and the signal transmission quality of the UC-EBG structural makes up the power plane as the high-speed signal current return path was compared with dielectric EBG structure.2)The effect of isolating SSN propagation by power plane segmentation technology was studied by using 3-D full-wave electromagnetic simulation software HFSS.The PCB experimental board using power plane segmentation technology and maintaining power/ground plane continue were fabricated and the experimental boards were tested using vector network analyzer and the tested S parameters were basically consistent with the simulation results verify the correctness of the simulation data obtained by HFSS.Then the HFSS was used to study the different effects of the segmentation type and the power island bridge mode on noise suppression.It can be seen from the electromagnetic simulation data and experimental data that the power plane segmentation technology has obvious noise isolation effect in the low frequency band,but in the high frequency band,due to the resonance of the power/ground plane,severe noise coupling occurs at the gap of the power plane segmentation.Hence,this paper proposes a combination of power plane segmentation technology and dielectric EBG structure technology to achieve wideband suppression of SSN and simulated by HFSS.It can be seen from the simulation data that the proposed method can achieve wideband suppression of SSN.Then the influence of the number of dielectric columns on the gap isolation on the noise isolation effect was further discussed.It is also stated that the introduction of dielectric EBG structure in power plane segmentation technology can improve signal transmission quality of power plane segmentation technology.In the above research,all the contents in the text are real and effective and can be directly used in the design and analysis of the actual high-speed digital system power distribution network.