【作者】 郭丰睿； 胡善清； 李兴明； 王雨薇；

【Author】 GUO Fengrui;HU Shanqing;LI Xingming;WANG Yuwei;Beijing Key Laboratory of Embeddeed Real-time Information Processing Technology,Beijing Institute of Technology;Department of Electrical,Engineering,Tsinghua Universiey;

【机构】 北京理工大学嵌入式实时信息处理技术北京市重点实验室； 清华大学电子系；

【摘要】 随着电子系统向高速、高密度方向发展,蛇形绕线成为高速PCB设计中克服空间限制、满足时序要求的重要途径。然而,随着信号速率的提升,蛇形绕线的寄生电容效应使得其实际时延与线长形成了由多种因素影响的非确定关系,单一的信号线"等长"原则已经不能满足"ps"级时序裕量要求。通过对蛇形线进行建模仿真,研究等长蛇形绕线的线高、线间距和信号频率影响信号时延的原理,并提出一种基于S参数的时延算法来量化蛇形线时延与三者之间的关系。结果表明,在一定的门限内,蛇形绕线时延和蛇形线高、平行绕线间距以及信号频率强相关,并呈现一定的函数关系;而超过一定门限后,蛇形绕线时延与三者关系不大。研究为电路设计人员提供了一套完善的蛇形绕线设计准则,可有效解决高速蛇形绕线等长不同步问题。更多还原

【Abstract】 With the development of electronic systems towards high speed and high density,the serpentine line becomes an accepted way to overcome the area constraints and satisfy the timing requirements in high-speed PCB designs.However,with the ever-increasing signal rate,several factors influence the uncertainty of the timing delay because of the parasitic capacitance effect of the serpentine winding,and the monotonous principle of "equal length " can’t meet the requirements of the "ps" timing margin.In this paper,the principle of the factors influencing the timing delay is firstly analyzed,including the line length,line spacing and signal rate of the serpentine line.And then,a parameterized serpentine line is modeled and simulated to obtain scattering(S) parameters,which is used for quantizing the timing delay.The results show that the timing delay of the serpentine line presents a strong correlation with serpentine line’s height,the parallel winding distance and the signal frequency within a certain threshold,and becomes uncorrelated when beyond the certain threshold.Thus,it provides a comprehensive design rule for the designers,and avoids the unsynchronized timing problems which caused by serpentine winding.更多还原