摘要：電磁干擾（EMI）和電磁兼容（EMC）測試是汽車應(yīng)用領(lǐng)域中串行器/解串器（SerDes）設(shè)計(jì)必須驗(yàn)證的參數(shù)，需要在設(shè)計(jì)之初謹(jǐn)慎考慮EMI和EMC問題，避免不必要的設(shè)計(jì)修改。以下應(yīng)用筆記詳細(xì)介紹了如何在SerDes系統(tǒng)中測試EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC" title="EMI/EMC">EMI/EMC的基本概念和技術(shù)指南。

　　引言

　　LCD視頻顯示屏在汽車領(lǐng)域的應(yīng)用越來越普遍，堅(jiān)固的設(shè)計(jì)、小巧的尺寸及低廉的成本使其非常適合安全、導(dǎo)航及信息娛樂系統(tǒng)。LCD顯示屏是數(shù)字裝置，每個(gè)像素為離散的數(shù)字值。由于驅(qū)動(dòng)這些顯示屏的媒體/圖像信號(hào)源通常也為數(shù)字格式，因此，數(shù)字鏈路是連接視頻信號(hào)源和顯示屏最簡單、性能最高的方式。視頻鏈路的數(shù)字通道必須具有足夠的帶寬，例如640 x 480像素的彩色顯示屏工作于30fps （幀/秒）。如果每個(gè)像素的紅、綠、藍(lán)信號(hào)僅有6位分辨率，對(duì)應(yīng)的數(shù)據(jù)率則為640 x 480 x 30 x 18 = 166Mbps。實(shí)際傳輸速率必須略高一些，因?yàn)檎９ぷ餍枰[時(shí)間。許多顯示屏具有更多像素和/或更高的像素分辨率，從而使碼率大大提升。串行器/解串器（SerDes）器件接收并行數(shù)字?jǐn)?shù)據(jù)，然后對(duì)其進(jìn)行串行轉(zhuǎn)換，以便傳輸。有些器件，例如MAX9209串行器，保持紅、綠和藍(lán)數(shù)據(jù)通道分離，三原色中的每種顏色為一個(gè)獨(dú)立的串行通道，另外還提供時(shí)鐘第4個(gè)通道。其它器件，例如MAX9247串行器，則將這些數(shù)據(jù)組合為單個(gè)串行通道，采用嵌入式時(shí)鐘信號(hào)。這兩種方法都會(huì)明顯提高傳輸基頻。盡管頻率增大會(huì)產(chǎn)生問題，但是為串行轉(zhuǎn)換后的信號(hào)提供具有適當(dāng)屏蔽和阻抗匹配的傳輸介質(zhì)相對(duì)比較容易。

　　EMI測試

　　汽車應(yīng)用中必須進(jìn)行EMI測試，確保處于工作狀態(tài)的系統(tǒng)不會(huì)干擾到周圍其他系統(tǒng)。針對(duì)空間輻射和傳導(dǎo)干擾進(jìn)行測試?？臻g輻射的測試主要使用天線，檢測系統(tǒng)通過自由空間向其他系統(tǒng)輻射的能力。設(shè)計(jì)不合理的SerDes系統(tǒng)無法滿足EMI技術(shù)指標(biāo)。相比之下，傳導(dǎo)干擾測試主要采用系統(tǒng)電源線上的電壓和電流探頭完成。由于SerDes系統(tǒng)很少直接連接到電源線，所以很少考慮傳導(dǎo)干擾。

　　EMC測試

　　與EMI測試類似，汽車應(yīng)用領(lǐng)域通過EMC測試確保系統(tǒng)不會(huì)被周圍其他系統(tǒng)干擾。由于新型汽車車體內(nèi)部存在大量電子系統(tǒng)，所有這些系統(tǒng)都存在電流、電阻并且工作頻率占據(jù)很寬的頻譜，因此很有必要進(jìn)行這項(xiàng)測試。EMC測試采用大電流注入（BCI），對(duì)被測系統(tǒng)來說是個(gè)難題。盡管BCI測試規(guī)范和方法依汽車廠商的不同而異，但通常涉及到頻率從幾MHz到1GHz較強(qiáng)的外部電磁場。

　　像素時(shí)鐘頻率選擇

　　正確選擇像素時(shí)鐘對(duì)EMI具有明顯影響，SerDes視頻鏈路類似于其它高速數(shù)字器件，會(huì)產(chǎn)生時(shí)鐘頻率整數(shù)倍的諧波輻射，由此檢測其EMI。汽車應(yīng)用領(lǐng)域，EMI輻射限制隨頻率變化。許多汽車制造商都在特定頻帶內(nèi)規(guī)定了相當(dāng)嚴(yán)格的限制。例如，433MHz是用于無線門禁（RKE）的頻率，往往是EMI規(guī)范中最嚴(yán)格的頻段。對(duì)于像素時(shí)鐘頻率為33MHz的系統(tǒng)，其13次諧波位于429MHz，這會(huì)嚴(yán)重干擾433MHz RKE頻帶。選擇稍低的32.7MHz頻率，可以將13次諧波移到425MHz，形成更寬松的頻率裕量。

　　SerDes PCB EMI/EMC測試的通用特點(diǎn)

　　●良好的接地對(duì)所有IC都是非常重要的設(shè)計(jì)準(zhǔn)則，對(duì)于SerDes系統(tǒng)尤其重要。所有接地引腳必須具有低阻，并連接到穩(wěn)定的接地區(qū)域。不建議將PCB分為多個(gè)區(qū)域。PCB元件層的覆銅區(qū)域，以及緊鄰下方采用連續(xù)覆銅區(qū)，這些都是常規(guī)準(zhǔn)則。使最上層的覆銅遠(yuǎn)離阻抗匹配地走線，最好保留至少3倍于差分對(duì)布線的間距。

　　●考慮每個(gè)接地點(diǎn)都采用了多個(gè)過孔，過孔的寄生電感是造成非理想特性的關(guān)鍵。采用多個(gè)過孔有助于減小電感，從而提高性能。

　　●對(duì)IC的電源端進(jìn)行旁路非常重要，特別是對(duì)于SerDes系統(tǒng)。類似于接地的考慮，電源引腳從電源側(cè)看必須具有低交流阻抗，尤其是低壓差分信號(hào)（LVDS）線路、I/O電源引腳以及用于鎖相環(huán)（PLL）電路的電源引腳。建議每個(gè)引腳連接兩個(gè)旁路電容，這兩個(gè)電容通常相差10倍至100倍（例如0.1?F和1nF）。最小電容應(yīng)距離需要去耦/旁路的電源引腳最近。

　　●可以考慮在SerDes系統(tǒng)的電源引腳使用磁珠，特別是LVDS線路、I/O電源引腳和PLL電源引腳，當(dāng)然，這一點(diǎn)適用于所有電源引腳。磁珠有助于減小高頻能量的輸入和輸出，選擇峰值阻抗為100Ω至600Ω、額定值至少為100mA的磁珠。

　　圖1所示為MAX9247串行器PCB的放大圖片，關(guān)鍵元件有FB4、C6和C5，這些元件被布置在一列，絲印參考點(diǎn)位于各自元件外框的右側(cè)。圖1底部為MAX9247的一角。FB4的右側(cè)端子通過一個(gè)過孔連接到嵌入式接地區(qū)域。FB4的左側(cè)端子向下連接至C6和C5，然后連接至MAX9247的引腳27，這是串行器的V*LL電源節(jié)點(diǎn)。注意，連接FB4、C5和C6的引線較寬，使寄生電感降至最低。由于該引線為了滿足MAX9247的引腳焊距而變窄，所以在C5和MAX9247之間使用了一個(gè)多邊形覆銅，保持盡量寬的引線，同時(shí)盡量靠近串行器。而且，C5和C6的接地顯示每個(gè)電容自身都具有連接至接地區(qū)域的過孔（每個(gè)元件的右側(cè)）。最上層覆銅區(qū)域?yàn)榻拥貙?，為C6和C5至MAX9247的引腳26提供直接的低電感連接通路，該引腳為串行器的PLLGND。

圖1. MAX9247的推薦旁路和接地設(shè)計(jì)

　　關(guān)于串行器的建議

　　抑制串行器的EMI輻射需要了解一些基本概念。通常情況下，串行器對(duì)EMC測試不是特別敏感；然而，其輸出需要具有阻抗固定的平衡傳輸線對(duì)。大多數(shù)串行器IC針對(duì)100Ω阻抗進(jìn)行優(yōu)化。如果設(shè)計(jì)中有不可更改的設(shè)計(jì)因素，接近該范圍的其它阻值也可以接受。如果串行器輸出需要連接到機(jī)箱以外，并入汽車線束，這些輸出就必須能夠承受對(duì)電池短路故障。最簡單的解決方案是采用0.1?F電容對(duì)每路輸出進(jìn)行交流耦合。然而，這樣需要一個(gè)直流平衡串行器，例如MAX9209、MAX9217或MAX9247。也可以使用非直流平衡器件，但系統(tǒng)設(shè)計(jì)必須保證所需偏壓由外部提供，而這通常不可行。最后，在串行器輸出接出PCB之前，輸出端往往連接一個(gè)共模扼流圈。這對(duì)串行器套件之外的共模噪聲抑制有一定保護(hù)作用。當(dāng)然，共模扼流圈的作用很有限，當(dāng)插入損耗（標(biāo)稱為1dB）影響到鏈路的可靠性時(shí)，則不應(yīng)使用。

　　關(guān)于解串器的建議

　　類似于串行器，設(shè)計(jì)工程師也需要遵循一些基本的概念和原則抑制解串器的EMI輻射。為避免解串器受EMC干擾，需要掌握一些基本要素，因?yàn)榻獯饕资蹺MC影響，同時(shí)也產(chǎn)生EMI輻射。

　　在解串器輸入端，靠近差分信號(hào)接入PCB的位置，往往放置共模扼流圈。共模扼流圈有助于減小共模噪聲的拾取，共模扼流圈在系統(tǒng)選定的工作頻率下必須具有較低的差分插入損耗。解串器輸入需要具有阻抗固定的平衡傳輸線對(duì)。大多數(shù)解串器針對(duì)100Ω阻抗進(jìn)行優(yōu)化，如果設(shè)計(jì)中存在不可更改因素，接近該范圍的其它阻值也可以接受。

　　如果解串器輸入需要交流耦合，可在共模扼流圈之后進(jìn)行隔直流。同樣，這些電容只能用于直流平衡解串器，例如MAX9236和MAX9248。差分對(duì)需要短接到100Ω差分阻抗，盡量靠近接收器側(cè)IC放置。差分阻抗保持在100Ω時(shí)，必須保持很低的共模阻抗?？梢允褂肨hevenin端接系統(tǒng)，或者將與中間節(jié)點(diǎn)串聯(lián)的一對(duì)50Ω電阻旁路至地，兩種連接方法如圖2所示。對(duì)于EMI/EMC測試來說，最好采用一對(duì)50Ω電阻，因?yàn)椋?/p>

　　●它允許IC設(shè)置自身的直流偏置；

　　●它不向終端注入VCC噪聲；

　　●它不消耗功率。

圖2. 正確的LVDS端接方法（左：Thevenin配置；右：串聯(lián)50Ω電阻配置）

　　連接器和線束

　　SerDes系統(tǒng)中使用的連接器和電纜是系統(tǒng)的關(guān)鍵部件，對(duì)EMI和EMC測試的影響非常顯著。汽車應(yīng)用領(lǐng)域的普遍做法是：規(guī)定鏈路兩端的PCB插座和電纜連接器由同一制造商提供。連接器必須保持固定阻抗，并提供屏蔽接口，以優(yōu)化性能。此外，必須使用單極插入或正極性鎖連接器，確?？煽啃?。

　　電纜也必須具有固定阻抗，線束要求嚴(yán)格屏蔽以防輻射。如果使用多線對(duì)電纜，每對(duì)電纜都需要單獨(dú)屏蔽。對(duì)于汽車SerDes，一般CAT5電纜即可滿需要求。

　　有許多制造商提供連接器和電纜系統(tǒng)，建議使用Rosenberger、JAE或Hirose產(chǎn)品。

　　有些系統(tǒng)中，連接器的屏蔽僅在鏈路一端接地，另一端則通過電容（典型為0.1?F）接地。這種耦合有助于避免地電位在電纜屏蔽層產(chǎn)生直流電流。

　　其它EMI源

　　SerDes視頻鏈路的另一個(gè)EMI源為解串器輸出。這些輸出為CMOS邏輯電平，相對(duì)為高速沿。如果CMOS邏輯輸出屏蔽不當(dāng)，也會(huì)引起EMI輻射。減小來自于LCD面板邏輯信號(hào)的最好辦法是采用具有擴(kuò)頻技術(shù)的解串器，例如MAX9242、MAX9244、MAX9246、MAX9248或MAX9250。這些解串器提供各種工作模式、數(shù)據(jù)寬度和工作頻率，以滿足大多數(shù)系統(tǒng)的要求。