摘要
分析了对称差分对共模电感的成因,并利用半波天线方法估计差分对的共模辐射.利用时域有限差分法计算差分对的共模辐射,估计了随着差分对布线向印刷电路板的边缘靠近时共模辐射的恶化情况和缩小差分对线距对共模辐射强度的抑制效果,并给出了高速互连的常用电平满足共模辐射规范下的布线规则,同时分析了保护走线对共模辐射的抑制效果.
Common-mode inductance of the differential line pairs on the printed circuit board （PCB） was analyzed, and the antenna theory was used to estimate the common-mode radiation of these differential line pairs. FDTD （finite-difference time-domain） method was used to calculate common-mode radiation of differential line pairs and estimate the deterioration of common-mode radiation when the differential line pairs are close to the board edge. The common-mode radiation suppression effect caused by reducing the distance between the two lines and the usage of the guard trace was investigated. The placement rule of the commonly used high speed connection level in PCB was proposed, and common-mode radiation suppression of the guard trace was discussed.
基金
安徽省高校"物理电子学"省级重点实验室资助.
关键词
差分对
共模电感
共模辐射
时域有限差分法
differential line pairs
common-mode inductance
common-mode radiation
FDTD method
