高速數位電路使用電磁能隙之共模濾波器分析與設計

Analysis Design of Common mode Filter for High-Speed Digital Circuits Using Electromagnetic Bandgap

蔡勝勛(Sheng-Shiun Tsai)

指導教授 ： 薛光華

中原大學/工學院/電子工程研究所/碩士(2010年)

https://doi.org/10.6840/cycu201000460

摘要

在現今高速數位電路產品中，差模訊號對經常被使用，差模訊號不易受外來 雜訊的干擾保持訊號的完整性，但由於高速數位電路產品結構日益減小，電路佈 線可以用範圍逐漸縮小，差模訊號線會產生傳輸線結構不對稱或轉折造成共模訊 號的產生，共模訊號的產生增加電磁干擾的問題，降低訊號的完整度，因此在未 來設計共模濾波器抑制共模雜訊是不可避免的。 在本論文提出寬頻的共模濾波器使用挖地缺陷結構技術，在接地面蝕刻週期 性大小圓形EBG 結構，EBG 微帶線結構在回流接地板上蝕刻週期性圓形結構形 成濾波器抑制雜訊，提供寬頻的抑制頻帶在20dB 時有5.2GHz 到25GHz 的頻寬。 由於濾波器的設計破壞接地面完整結構，影響差模訊號的完整，針對差模訊號特 有的耦合係數對共模濾波器的影響，提出差模訊號線上的阻抗補償設計提供訊號 的完整性，最後訂定共模濾波器的設計流程方便使用者設計濾波器結構。

關鍵字

電磁能隙 ； 共模濾波器

並列摘要

The differential signal is often using in high-speed digital circuits that can
maintain signal integrity and decrease noise interference. The product structure of
high-speed digital circuit diminishes gradually. The signal can layout area precious
relatively. The differential signal can have bend or unbalanced structure result in
common mode noise occurrence. The common mode noise will worsen the
electromagnetic interference and degrade the signal integrity. Now, the common mode
filter was designed suppression common mode noise.
In this thesis, defected ground structure (DGS) technology be used to broadband
common mode filter. The multi-period taped-etched electromagnetic bandgap (EBG)
was etched in the return ground. The use of etched EBG structures on the ground
plane is common in current research; it provides suppression for filter. The rejection
band of filter is from 5.2GHz to 25GHz by over 20dB. Because the ground plane was
not solid, the differential signal degraded signal integrity. The influences of the
coupling coefficient of differential line on the common mode filter suppression
common mode noise. Impedance compensation for differential traces is also proposed
to improve signal integrity. At last, this paper provided the common mode filter
design rule to reject bandgap.

並列關鍵字

Common mode filter ； EBG

參考文獻

[2] C. R. Paul, Introduction to Electromagnetic Compatibility, 2nd ed. New York:

[4] Chong C.K., McDermott D.B., Razeghi M.M., Luhmann Jr., Pretterebner

reflectors, ”Plasma Science, IEEE Transactions on, vol. 20, issue 3, pp.

[5] D. Ahn, J. S. Park, C. S. Kim, J. Kim, Y. Qian, and T. Itoh, “A design of the

low-pass filter using the novel microstrip defected ground structure,” IEEE