Signal Transmission Analysis of Differential Pairs Using Semicircle-Shaped Via Structure

In this paper, the signal transmission analysis of the semicircle-shaped via structure for the differential pairs is presented in the frequency range up to 10 GHz. In order to improve the signal transmission properties in the differential pairs, single via is separated centrally into two semicircle-shaped sections, which are interconnected with the traces of differential pairs respectively. This via structure make possible to route differential pairs using only one via. In addition, it can improve impedance discontinuity around its region and then enhance the signal transmission properties in the differential pairs. The electrical analysis such as S-parameter calculation and eye diagram simulation has been performed to investigate the improvement of the signal transmission property in the differential pairs with new via structure.

Authors:

• Moonjung Kim
• Chang-Ho Hyun
• Won-Ho Kim

Keywords:

• Differential pairs
• signal transmission property
• via
• S-parameter.

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