ESD保护电路在HDMI板级信号完整性中的影响分析及其布局优化研究OACSTPCD

In order to solve the problem of signal integrity damage after HDMI is connected to ESD(electrostatic discharge)protection circuits,the effectegrity of HDMI signal is analyzed.Considering the influence of high-frequency parasitic parameters in transient voltage suppression(TVS),the ESD discharge model and TVS high frequency equivalent circuit model are established and their reliability is verified.The influence on signal integrity was studied from rotation angle and staggered distance of differential device access signal lines.Twenty-five sets of plate-level models with different angles and four sets of different staggered distances are designed,and S-parameter simulation is carried out under different transmission frequencies with different characteristics.Three representative spatial layout models,vertical,horizontal,and staggered,are selected.The S-parameter and the eye chart of the difference signal line were obtained by means of the finite element simulation.The simulation results show that,compared with the other two typical spatial layouts,the return loss and insertion loss of the vertical layout are reduced by 248.1%and 20.6%on average.The eye width and eye height of the eye chart are the largest among the three spatial layouts.The results provide layout optimization guidance for the analysis and design of PCB electrostatic discharge protection circuits.