Study On Power Integrity Of High-speed Circuits System

With the continuous development of high-speed circuits, power integrity (PI) has become an equally important issue as signal integrity (SI). The main problems of PI are the design of the power distribution network (PDN) and the suppression of simultaneous switching noise (SSN). In order to ensure the system stability, people need to study the effects of various components of PDN on PI. Since the PDN is the main transmission of SSN, in order to suppress the interference of SSN, during the design of PDN, we need to take the certain measures to suppress the spread of SSN.In this paper, taking two-layer PCB board as the research object, firstly, we analyze the function and impact of the various components of PDN on the power integrity, focusing on generation mechanisms of SSN and the important effect of the decoupling capacitors on SSN suppression and ensuring power transmission; secondly, for the plenty of ground vias of PDN, researching the effect of ground via for PI and analyzing the effect of the number and size of ground via, the relative position and distance of the port and the ground via on input impedance and noise radiation characteristics of the certain port. Finally, putting forward complementary split-ring resonator (CSRR) for suppressing SSN, with the distributing circuit modeling,building the model of power/ground with CSRR and verifying the feasibility. Then, with the model, we study the effect of different structural parameters of CSRR on SSN suppression and the effect of CSRR on signal transmission. The results shows the use of differential signal lines can effectively suppress the interference of CSRR on SI.On the high-speed PCB, ground via is the most number of structure. The study of ground via can provide a rule for the design of PDN, to determine vias’the position and quantity, reaching the balance between input impedance suppression and noise radiation suppression. Respecting to other structures, CSRR has better SSN inhibition effect on suppression depth, suppression width, low cut-off frequency. Moreover, studying and analyzing the effect of different structural parameters of CSRR on SSN suppression can help designers adjust structural parameters to reach the specific designed requirements when using CSRR to suppress SSN.