摘 要 高清晰多媒體介面(High Definition Multimedia Interface 簡稱HDMI)是一種目前主流的全數位化影像及聲音傳送介面,可以同時傳送音訊和視訊訊號,其多應用於電視機、機上盒、筆記型電腦、DVD播放機、電視遊樂器、綜合擴大機、數位音響……等裝置,由於高速數位訊號(解析度3840*2160@60Hz)快速切換時易造成電磁干擾(Electro Magnetic Interference,簡稱EMI)問題,EMI電磁輻射過高,以致干擾其他設備正常運作,超出國家法規的標準,本技術報告探討針對高速訊號線路,如何改善電磁干擾之問題。增加遮蔽方式可抑制電磁輻射散射干擾;而馬口鐵遮蔽之厚、薄度差異分析,實驗數據之結果顯示並無顯著差異。此結果可為產品設計選用遮罩設備時,如何同時兼顧最佳的性能與成本做為考量。
Abstract The High Definition Multimedia Interface (HDMI) is one of the digital video/audio interfaces for transmitting audio- and video-data signals concurrently, which can be applied for TV, set-top box, laptop computer, DVD player, video game player, amplifier, and digital audio player. However, due to a fast transition time of the high speed digital signals, it will produce an electromagnetic interference (EMI), and then disturb other devices' normal operation which would cause products fail to pass the EMI specfications. This technique report investigates how to use metal shielding to improve the EMI phenomenon. Furthermore, we also analyze the impact of the tinplate shielding thickness to obtain an optimization design, where the results show that there is no big difference related to the tinplate shielding thickness.