为解决高速光收发模块中PCB差分布线由于过孔引起的不匹配及信号完整性问题, 首先利用HFSS、Hyperlynx等软件对差分过孔进行了建模研究和分析。在此基础上提出了通过差分补偿和增加接地过孔的方法, 可以实现差分线匹配, 从而改善信号完整性。随后, 通过HFSS仿真分别对两种方法在传输损耗和反射上的表现进行了验证, 并分析、比较了两种方法的特点。最后, 进行了2.5G光模块测试, 测试结果证明了改进方法的有效性。

To solve the problems of mismatching and signal integrity caused by the via holes in differential traces in highspeed optical transceiver, HFSS and Hyperlynx were used to make modeling research and analysis on the differential via holes. On this basis, two methods of differential compensation and adding GND via holes were proposed to realize the matching of differential traces and improving the integrity of signal. Subsequently, the performance of the two methods on transmission loss and reflection was verified by HFSS simulations, and then the characteristics of the two methods were analyzed and compared. Finally, tests were carried out on 2.5G optical transceiver and the results prove the effectiveness of the proposed methods.