不符合20H规则的阻抗线参考层设计对阻抗测量的影响

Effects of ground layer design not aligned to 20-H rule on characteristic impedance of PCB

20 H规则作为PCB典型布线规则,随着传输信号工作频率逐步提高,其越来越被PCB设计人员采用以用来减少EMI问题。当然,PCB制造人员无法模拟20 H规则的EMI但须控制特性阻抗,故本文试图首次阐述20 H规则对特性阻抗控制的影响,并通过相关试验与量产过程进行证明。

As the operating frequency goes higher, 20-H rule is often applied by more and more PCB designers to reduce electromagnetic interference （EMI） problems, namely, the 20-H rule is an important guideline of printed circuit board layout. Obviously, PCB manufacturers cannot simulate EMI but should measure characteristic impedance in the actual production. So this paper wants to introduce the effects of ground layer design not aligned to 20H rule on impedance control, with veriifed by experiments and production practices.