高密度服务器的传导骚扰溯源及整改

Tracing and Rectification of Conducted Disturbance of High Density Server

某急需量产服务器的传导骚扰测试超标,从分析电磁干扰的原理与路径出发,确认直流开关电源为干扰源。服务器主板的布线密度很高,对整改造成了很多限制。通过将网口连接器输出端地悬空设计,在保证高速信号参考地完整性的前提下,阻断了干扰信号路径。通过结构优化使主板连接器外壳和机箱外壳之间保持低阻抗连接,使外界强干扰可通过此路径泄放到机箱外壳,内部电路得到保护。整改后,高密度服务器的传导骚扰测试合格。

The conducted disturbance test of a server in urgent need of mass production exceeds the standard.Based on the analysis of the principle and path of electromagnetic interference,DC switching power supply is confirmed as the interference source.The layout density of the server motherboard is very high,which causes many restrictions on the rectification.By suspending the output end of the network port connector from the ground,the interference signal path is blocked on the premise of ensuring the integrity of the high speed signal reference ground.Through the structure optimization,the low impedance connection between the motherboard connector shell and the chassis shell is maintained,so that the external strong interference can be discharged to the chassis shell through this path,and the internal circuit is protected.After rectification,the conducted disturbance test of high density server is qualified.