【作者】 石海霞；

【导师】 王晓华；

【作者基本信息】 电子科技大学 ， 无线电物理， 2015， 硕士

【摘要】 本文旨在研究高速电源分配网络(PDN)中的同步开关噪声(SSN)和信号完整性(SI)。首先针对已有的电磁带隙(EBG)结构抑制SSN的不足,提出新型的EBG结构来增大抑制SSN的带宽;其次在SI方面,通过新型的加“桥”设计方法使信号的质量得到了良好改善,同时,方法还降低了EBG结构单元之间的IR压降(IR-Drop)。另外,所设计的EBG结构与传统的PDN相比具有较低的电磁干扰(EMI);最后,由于PDN中大部分电路采用差分传输方式来解决SI、EMI问题,本文还设计了几款基于基片集成波导(SIW)结构的差分滤波器。具体研究工作如下:SSN抑制方面:在0-8GHz的噪声范围内,由于电源/地板结构固有的腔谐振模式,使得SSN可在板间传输,导致集成电路中各个模块间的电磁耦合,而EBG结构因其高阻面特性可在一定程度上抑制这种噪声,但单元中仍然存在TM11和TM22谐振模式,其在所关注的噪声频段内,因此不能在整个噪声频段抑制电磁噪声。本文针对EBG结构的腔模场分布特点,选择模式能量最弱的地方加载金属线可有效降低TM11模式能量在PDN中的传播,在单元间金属连线上加入四分之一波长开路支节谐振器使在该波长所对应的频率点产生谐振抑制TM22模式,以此来增加SSN抑制带宽。SI提高方面:在0-8GHz带宽内,作为信号线的参考平面的EBG结构电源面不连续,将会影响回流路径,增加回流电感,从而严重影响信号的完整性。为此,本文通过在信号线旁边加载一电感大小合适的“桥”来为信号的回流提供更短的路径达到改善信号质量的目的。同时,方法还降低了IR-Drop,保证了PDN为芯片提供“粮食”的效率。所设计的电路板样品与参考板相比具有较低的EMI,仿真与测量结果采用特征选择验证(FSV)工具进行了验证,具有较好的吻合。最后,由于PDN中部分电路采用差分传输方式来解决SI、EMI问题,为了抑制信号中的共模噪声,根据奇偶模分析法和TE102腔可使共模信号短路的特点设计了三类基于SIW的差分滤波器。另外,根据巴伦结构的平衡端信号幅度相等相位相反的特点将两个巴伦的非平衡端进行对接实现了基于巴伦结构的SIW差分滤波器。仿真结果显示上述四类差分滤波器具有良好的差分选择性和共模抑制能力。更多还原

【Abstract】 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.更多还原