高清晰多媒體介面訊號強度對眼圖及電磁干擾之分析

Level Strength Effect on Eye Diagram and Electromagnetic Interference for High Definition Multimedia Interface Systems

陳睦棨(Mu-Chi Chen)

指導教授 ： 丘建青

淡江大學/工學院/電機工程學系碩士在職專班/碩士(2016年)

https://doi.org/10.6846/TKU.2016.00464

摘要

高清晰多媒體介面HDMI（High-definition multimedia interface）是一種全數位化影像及聲音傳送介面，在現在的科技進步之下，在電腦上已經是非常普及的輸出裝置了，但是在這樣的高速訊號的傳輸之下，電磁干擾（Electromagnetic Interference，簡稱EMI）一直是工程師要去解決的問題，時常為了解決HDMI的EMI問題加入電子的對策，往往導致眼圖無法達到標準，或者是在機殼上做大量的屏蔽，使成本提高。
　　本論文使用有裝載HDMI介面的筆記型電腦做研究，此筆記型電腦產品裝置的平台為英特爾（Intel）處理器，此平台提供了幾個參數給工程師在基本輸出輸入系統（Basic Input/Output System，簡稱BIOS）裡調降HDMI訊號強度，本論文在量測後，分析各種常見及本文提出的解決方案，結果顯示以往常見的解決方式改善效果有限並且增加成本，而本論文所提供的方式，HDMI可在不需要增加成本以及更改電路設計的情況之下，成功的控制眼圖及EMI的品質，其BIOS調整方式有下列三種：

1.只需要眼圖Pass的情況可以選擇預設值1000mV0.0dB或調降位準強度至800mV0.0dB。
2.需要EMI可以Pass的情況，可以將位準強度調降至800mV0.0dB或600mV0.0dB。
3.若是要眼圖及EMI同時要達到法規標準，將位準強度調降至800mV0.0dB即可。

關鍵字

高清晰多媒體介面 ； 電磁干擾 ； 眼圖 ； 基本輸出輸入系統

並列摘要

HDMI (high-definition multimedia interface) is a digital interface to transfer image and sounds. It is a common output device for the development technology in recent years. However, EMI (Electromagnetic Interference) is an important issue in such high speed transmission and a lot of problems need to be resolved. Some techniques without extra cost for reducing EMI issues deteriorate eye diagram and some techniques increase the cost by placing numerous shielding on metal chassis.
In this thesis, we will focus on the research for note book using Intel processer with HDMI output. It provides a few modification parameters to adjust the signal strength in the Basic Input/Output System (BIOS). It is found that, without increasing the cost and changing the layout, the eye diagram and EMI could be compromised by our proposed techniques for adjusting the level output of BIOS as the following:

1. To satisfy the criteria for eye diagram, the level strength can be set as the default value 1000mV0.0dB or reduce to 800mV0.0dB.
2. To satisfy the criteria for EMI, the level strength can be set as 800mV0.0dB or 600mV0.0dB.
3. To satisfy the criteria for both eye diagram and EMI, the level strength must be set as 800mV0.0dB.

Finally, compared to the conventional techniques, our proposed techniques can improve both eye diagram and EMI without increasing the cost and changing the layout.

並列關鍵字

HDMI(high-definition multimedia interface) ； EMI(Electromagnetic Interference) ； eye diagram ； BIOS(Basic Input/Output System)

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