Research On Electromagnetic Noise Suppression And Signal Integrity In High-speed Power Distribution Network

The aim of this thesis is to study simultaneous switching noise(SSN) and signal integrity(SI) in power distribution network(PDN). At first, for the deficiency of existing electromagnetic band gap(EBG) structure, this thesis proposed a novel EBG structure to broaden the suppression bandwidth of SSN; secondly, by adding “bridge”, this method not only improves the SI, but also reduces the IR-Drop. The proposed EBG structure possesses low electromagnetic interference(EMI) compared with the traditional PDN; finally, most circuits in PDN use the differential transmission line to solve the problem of SI and EMI, in this thesis, four differential bandpass filters based on substrate integrated waveguide(SIW) are proposed and studied to suppression common mode noise. The specific work is as follows:For inhibition of SSN: in the noise bandwidth of 0-8GHz, the inherent resonant cavity mode of power/ground structure will cause the electromagnetic coupling between each module in the integrated circuit, which makes the SSN transmit in the board. The EBG structure with high impedance surface characteristics can suppress the noise in a certain extent, but generally TM11 and TM22 resonant mode still exist in the concerned noise band. According to the cavity mode field distribution of EBG structure, choosing the middle of the metal patch edge as the bridge connecting point can reduce the TM11 mode energy in the PDN. Adding quarter wavelength open stubs to the metal connecting line can suppress the TM22 mode. So the proposed method can increase simultaneous switching noise(SSN) bandwidth greatly.For the improvement of SI: in the noise bandwidth of 0-8GHz, the discontinuities on power plane of EBG structure will affect the return signal path so as to influence the SI. In this thesis, by placing appropriate inductance of “bridge” next to signal line to provide short pass for the return circuit, it can improve the signal integrity. This method also can reduce IR Drop from the last results. The final processing circuit board has low EMI compared with reference boards, and the simulation results and the measured results are with good agreement verified by feature selection verification(FSV) tool.Finally, since most circuit in PDN by using the differential transmission mode to solve the SI and EMI, in order to suppress the common mode noise, the even and odd mode method and the law of the TE102 cavity will let common mode signal cancellation. Based on the theory, three kinds of SIW differential filter have been studied. Finally according to the characteristics of balun structure, we connect two baluns’ unbalanced end to form a SIW differential filter based on balun theory. The four types of differential filter have good characteristics in differential selectivity and common mode rejection capability.