<div align="left" style="line-height: 2.2;"><span style="font-family: 돋움, Dotum;">※ PCB 설계 입문에 목적을 두고 정보검색/취합/정리하여 포스팅되었다.</span></div>
<div align="left" style="line-height: 2.2;"><span style="font-family: 돋움, Dotum;">※ 가능한 한 필요한 모든 사항을, 깊게 들어가지 않고 간략하게 조사 후 정리하였다.</span></div>
<div align="left" style="line-height: 2.2;"><span style="font-family: 돋움, Dotum;">※ 틀린 부분이 있을 수 있습니다. 지적 바랍니다.</span></div>
<div align="left" style="line-height: 2.2;"><span style="font-family: 돋움, Dotum;"><span style="font-size: 9pt;"><b><br /></b></span></span></div>
<div align="left" style="line-height: 2.2;"><span style="font-family: 돋움, Dotum;"><span style="font-size: 9pt;"><b>목차</b></span></span></div>
<div align="left" style="line-height: 2.2;"><span style="font-family: 돋움, Dotum;"><span style="font-size: 9pt;"><b>1. PCB 구조</b></span></span></div>
<div align="left" style="line-height: 2.2;"><span style="font-size: 10pt; font-family: 돋움, Dotum;"><span style="font-size: 9pt;">&nbsp;1-1. PCB 기판재</span></span></div>
<div align="left" style="line-height: 2.2;"><span style="font-size: 10pt; font-family: 돋움, Dotum;"><span style="font-size: 9pt;">&nbsp;1-2. 구리층</span></span></div>
<div align="left" style="line-height: 2.2;"><span style="font-size: 10pt; font-family: 돋움, Dotum;"><span style="font-size: 9pt;">&nbsp;1-3. Soldermask</span></span></div>
<div align="left" style="line-height: 2.2;"><span style="font-size: 10pt; font-family: 돋움, Dotum;"><span style="font-size: 9pt;">&nbsp;1-4. Silkscreen</span></span></div>
<div align="left" style="line-height: 2.2;"><span style="font-size: 10pt; font-family: 돋움, Dotum;"><span style="font-size: 9pt;">&nbsp;1-5. PCB 표면처리</span></span></div>
<div align="left" style="line-height: 2.2;"><span style="font-family: 돋움, Dotum;"><span style="font-size: 9pt;"><b>2. 배경지식</b></span></span></div>
<div align="left" style="line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;2-1. 주파수와 파장길이의 관계</span></div>
<div align="left" style="line-height: 2.2;"><span style="font-size: 10pt; font-family: 돋움, Dotum;"><span style="font-size: 9pt;">&nbsp;2-2. EMC</span></span></div>
<div align="left" style="line-height: 2.2;"><span style="font-size: 10pt; font-family: 돋움, Dotum;"><span style="font-size: 9pt;">&nbsp;2-3. 노이즈 분류</span></span></div>
<div align="left" style="line-height: 2.2;"><span style="font-size: 10pt; font-family: 돋움, Dotum;"><span style="font-size: 9pt;">&nbsp;2-4. 임피던스</span></span></div>
<div align="left" style="line-height: 2.2;"><span style="font-family: 돋움, Dotum;"><span style="font-size: 18.6667px;"><b><br /></b></span></span></div>
<div align="left" style="line-height: 2.2;"><span style="font-family: 돋움, Dotum;"><span style="font-size: 10pt;"><b>&nbsp;</b></span></span></div>
<div align="center" style="line-height: 2.2; text-align: center;"><b><br /></b></div>
<div align="center" style="line-height: 2.2; text-align: center;"><b style="font-size: 12pt;"><span style="font-size: 14pt; font-family: 돋움, Dotum;">1. PCB&nbsp;구조</span></b></div>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T2" style="font-size: 11pt; font-family: 돋움, Dotum;"><b>1-1. PCB 기판재</b></span><span class="se_fs_T3"><br /></span><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- PCB 기판재는 전기적 특성이 뛰어난 수지(Resin)를 기초 재료로 하여, 기계적 강도와 내열성을&nbsp;보완하기 위해</span><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;보강기재를&nbsp;첨가한다.&nbsp;</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- PCB 기판재의 재질은 기판의 최고전압, 주파수 특성 등을 결정한다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;※<span class="se_fs_T3">&nbsp;TG(유리전이온도)는&nbsp;입자간의 구속력이 떨어져&nbsp;물리적 변형이 일어날 수 있는 온도이다.</span></span></p>
<p style="padding: 0px; line-height: 2;"><br /></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- PCB 기판재의 종류는 아래 표와 같다.</span></p>
<p style="padding: 0px; line-height: 2;"><span class="se_fs_T3"></span></p>
<p style="padding: 0px; line-height: 2;"><span class="se_fs_T3"><span class="se_fs_T3"></span></span></p>
<table style="table-layout: fixed; border-width: 0.28pt; border-style: solid; border-color: #000000;">
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            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;"><b>보강기재</b></span></p>
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            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;"><b>수지</b></span></p>
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            <p class="0" style="padding: 0px; line-height: 2.2;"><b><span lang="EN-US" style="letter-spacing: 0pt; font-family: 돋움, Dotum;">NEMA</span><span style="font-family: 돋움, Dotum;">규격</span></b></p>
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            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;"><b>주용도</b></span></p>
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            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;"><b>가격</b></span></p>
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            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;"><b>강도</b></span></p>
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            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">종이</span></p>
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            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">페놀</span></p>
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            <p class="0" style="padding: 0px; line-height: 2.2;"><span lang="EN-US" style="letter-spacing: 0pt; font-family: 돋움, Dotum;">FR-1/2, XPC..</span></p>
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            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">가전제품 단면&nbsp;</span><span lang="EN-US" style="letter-spacing: 0pt; font-family: 돋움, Dotum;">PCB</span></p>
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         <td valign="middle" style="word-break: break-all; width: 79.37pt; height: 12.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">매우저렴</span></p>
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            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">매우약함</span></p>
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            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">종이</span></p>
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         <td valign="middle" style="word-break: break-all; width: 48.24pt; height: 12.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">에폭시</span></p>
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            <p class="0" style="padding: 0px; line-height: 2.2;"><span lang="EN-US" style="letter-spacing: 0pt; font-family: 돋움, Dotum;">FR-3</span></p>
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            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">가전제품&nbsp;</span><span lang="EN-US" style="letter-spacing: 0pt; font-family: 돋움, Dotum;">PCB</span></p>
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         <td valign="middle" style="word-break: break-all; width: 79.37pt; height: 12.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">저렴</span></p>
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            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">약함</span></p>
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            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">유리</span><span lang="EN-US" style="letter-spacing: 0pt; font-family: 돋움, Dotum;">+</span><span style="font-family: 돋움, Dotum;">종이</span></p>
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            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">에폭시</span></p>
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            <p class="0" style="padding: 0px; line-height: 2.2;"><span lang="EN-US" style="letter-spacing: 0pt; font-family: 돋움, Dotum;">CEM-1/3</span></p>
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            <p class="0" style="padding: 0px; line-height: 2.2;"><span lang="EN-US" style="letter-spacing: 0pt; font-family: 돋움, Dotum;">SMPS PCB</span></p>
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            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">중간</span></p>
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            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">중간</span></p>
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            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">유리</span></p>
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         <td valign="middle" style="word-break: break-all; width: 48.24pt; height: 12.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">에폭시</span></p>
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         <td valign="middle" style="word-break: break-all; width: 93.52pt; height: 12.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2;"><span lang="EN-US" style="letter-spacing: 0pt; font-family: 돋움, Dotum;">FR-4</span></p>
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            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">산업용&nbsp;</span><span lang="EN-US" style="letter-spacing: 0pt; font-family: 돋움, Dotum;">PCB</span></p>
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            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">비쌈</span></p>
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            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">강함</span></p>
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<p style="padding: 0px; line-height: 2;"><span class="se_fs_T3"><b><br /></b></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3" style="font-family: 돋움, Dotum;"><b>1-1-1.&nbsp;종이페놀 기판재 (FR-1/2, XXXPC, XXPC, XPC...)</b></span><span class="se_fs_T3"><br /></span><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- 매우 저렴한 단면 기판재로써, 만능기판과 같은 재질(페놀)이다.<br /></span><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;-&nbsp;단,&nbsp;</span><span class="se_fs_T3" style="font-family: 돋움, Dotum;">기계적 강도와 내열성이 약하고, 전기적 특성이 떨어지며, 습</span><span class="se_fs_T3" style="font-family: 돋움, Dotum;">기에 약하므로 변형이 일어나기 쉬워, 보관할때도 눕혀야한다고 한다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3" style="font-family: 돋움, Dotum;"><br /></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"></span></span><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;"><b>1-1-2. 유리에폭시 기판재 (FR-4/5, G10/11...)</b></span></span><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;</span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- 결고 저렴하지 않은 기판재이다.</span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;-&nbsp;전기적 특성, 수치안정성, 내열성, 내약품성, 기계적 강도 등 모든 부분에서 우수하다.<br /></span><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- 유리에폭시 기판재의 일종인 FR-4 (Flame Retardant 4)는 현재 가장 널리 사용되는 기판재이다.&nbsp;(TG=120~130'C)<br /></span><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;-&nbsp;</span><span class="se_fs_T3" style="font-family: 돋움, Dotum;">최근 FR-4에서 TG를 향상시킨 FR-5 수요가 증가하고 있다 (TG=140~170'C)</span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;"><br /></span><span class="se_fs_T3"></span></span><span class="se_fs_T3" style="font-family: 돋움, Dotum;"><b>1-1-3. 유리기재에폭시 기판재 (CEM-1/3)</b></span><span class="se_fs_T3"><span class="se_fs_T3"></span></span><span class="se_fs_T3">&nbsp;</span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- 하얀색 실장면이 특징이며,&nbsp;국내에서는 거의 단면&nbsp;기판으로 사용한다.<br /></span><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- 무거운 부품, 열이 많이 나는 부품 등의 실장에 유리하여,&nbsp;</span></span><span class="se_fs_T3" style="font-family: 돋움, Dotum;">SMPS에서 주로 사용한다.</span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;"><br /></span><span class="se_fs_T3"></span></span><span class="se_fs_T3" style="font-family: 돋움, Dotum;"><b>1-1-4.&nbsp;기타</b></span><span class="se_fs_T3"><span class="se_fs_T3"><br /></span><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- Teflon 기판재&nbsp;:&nbsp;고주파, 특히 무선통신&nbsp;PCB에 사용.<br /></span><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- Aluminum 기판재 :&nbsp;방열이 필요한 모터/LED 등에 사용. -&gt; Ceramic PCB로 대체할 수 있다고 한다.<br /></span></span><span class="se_fs_T3"><span class="se_fs_T3"><br /><br /><br /></span><span class="se_fs_T3"></span></span><span class="se_fs_T2"><span class="se_fs_T2" style="font-family: 돋움, Dotum; font-size: 11pt;"><b>1-2. 구리층</b></span></span></p>
<p><img src="https://blogfiles.pstatic.net/MjAxODA2MjNfMyAg/MDAxNTI5NzA1MTIzMjkz.qG3YMsOQfEr-EAamM6GF4uxEPA73VfN8TkmxZH1ui-cg.J_n2UCmncuBSwSXmZfxMzE_-gyYShenp3NlsBh-lwvcg.JPEG.bae3421_/dthumb-phinf.pstatic.jpg?type=w2" width="320" height="197" id="MjAxODA2MjNfMyAg/MDAxNTI5NzA1MTIzMjkz.qG3YMsOQfEr-EAamM6GF4uxEPA73VfN8TkmxZH1ui-cg.J_n2UCmncuBSwSXmZfxMzE_-gyYShenp3NlsBh-lwvcg.JPEG.bae3421_/dthumb-phinf.pstatic.jpg" alt="" class="_photoImage" data-lazy-src="" style="border: 3px solid rgb(255, 255, 255); cursor: pointer; clear: both;" /></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- 실제 회로가 담긴 동박이 있는 층으로, 두께는 무게로 분류된다.&nbsp;</span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- 1oz (1ft^2당 1oz, 28.35g)가 대중적이다.&nbsp;이때 두께는 약 35um이다.</span><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;</span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- 큰 전력이&nbsp;흐르거나 PCB에&nbsp;발열이 심한경우, 구리층을 2oz,&nbsp;3oz 등으로 두껍게 사용하기도 한다.<br /></span><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- 구리층 수는 곧 PCB 층수를 의미하는데,&nbsp;</span></span></span><span style="font-family: 돋움, Dotum;">적게는 단면(1층), 양면(2층)부터, MLB(Multi Layer Board, 수십층 단위)까지도 존재한다.&nbsp;</span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- 다층 PCB의 경우 그 중 2개 이상의&nbsp;구리층은 전원층, 접지층으로 사용된다.</span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;"><br /></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;"><br /></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><b><span style="font-family: 돋움, Dotum; font-size: 11pt;">1-3. Solder mask</span></b></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><img src="https://blogfiles.pstatic.net/MjAxODA2MjNfMTMw/MDAxNTI5NzA1MTIyOTcw.VZhdmxF7tOns9kft8JEOWlOOTLCiH-cMvafxDvDeAgIg.ihdw9skpVk0qYTQ2HM5i8xvYGH2pVL5I_jRksaOd-kEg.JPEG.bae3421_/50d498fcce395f600d000001.jpg?type=w2" width="320" height="292" id="MjAxODA2MjNfMTMw/MDAxNTI5NzA1MTIyOTcw.VZhdmxF7tOns9kft8JEOWlOOTLCiH-cMvafxDvDeAgIg.ihdw9skpVk0qYTQ2HM5i8xvYGH2pVL5I_jRksaOd-kEg.JPEG.bae3421_/50d498fcce395f600d000001.jpg" alt="" class="_photoImage" data-lazy-src="" style="border: 3px solid rgb(255, 255, 255); cursor: pointer; clear: both;" /></span><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;</span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- 구리층 위에 있는 절연층이다.</span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- 사진에서 진한초록색이 FR4위에 Solermask가 덮인것이고, 연한 초록색은 구리층 위에 Soldermask가 덮인 것이다.</span></span></span><span style="font-family: 돋움, Dotum;">&nbsp;</span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- 납땜 시 필요한 부분에만 납이 붙도록 하고, 나머지 동박은 산화/오염, 외부에 의한 쇼트으로부터 보호하는 주 목적을 가지고 있다.</span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- Solder Mask를 구성하는 절연잉크(S/R, Solder Resist)를 구리층에 코팅하는 과정을 PSR(Photo SR)라고 한다.</span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- 이때 절연잉크(SR)는 PCB의 색깔을 결정짓는다. (주로 초록색)</span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;"><br /></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum; font-size: 11pt;"><b>1-4. Silkscreen</b></span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- Solder mask 층 위에 입혀지는, 주로 하얀색의 보조선이다.</span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 부품의 관리번호(레퍼런스)나</span><span style="font-family: 돋움, Dotum;">&nbsp;가이드라인 등을 표시하여,&nbsp;</span><span style="font-family: 돋움, Dotum;">조립을 쉽게하거나 회로를 더 잘 이해하도록 돕는 목적을 가진다.</span></p>
<p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;"></span><span style="font-family: 돋움, Dotum;">&nbsp;</span></p>
<p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;"><br /></span></p>
<p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;"><br /></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-size: 11pt; font-family: 돋움, Dotum;"><b>1-5. PCB 표면 처리</b></span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- Solder mask가 입혀지지 않은 노출된 동박을 코팅하여 산화방지, SMT용이성 등을 확보하는 작업이다.</span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;"><br /></span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><b><span style="font-family: 돋움, Dotum;">1-5-1. HASL (Hot Air Solder Leveling)</span></b></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 저렴하고, 긴 보관 수명을 가진다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 가장 오래된 표면 처리 기법으로, 표면 처리 과정에서 납이 함유되지만 RoHS를 위한 무연 HASL이 따로 있긴 하다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 표면이 균일하지 못하고, 미세 피치의 소자를 탑재하기 어렵다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;-&nbsp;솔더브릿지가 생길 수 있고, 도금 스루홀의 막힘/좁아짐이 나타날 수 있다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- HASL는 PCB 두께 0.6T 부터 가능하다. (한샘디지텍)</span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;"><br /></span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><b><span style="font-family: 돋움, Dotum;">1-5-2. OSP (Organic Solderability Preservative)</span></b></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 저렴하지만, 보관수명에 제한을 가진다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 많이 사용되는 표면처리기법이다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 표면이 평평하고, 납을 함유하지 않는다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;"><br /></span></p>
<p style="padding: 0px; line-height: 2.2;"><b><span style="font-family: 돋움, Dotum;">1-5-3. ENIG (Electroless Nickel with Immersion Gold coatting)</span></b></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 비싸지만, 긴 보관 수명을 가진다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 많이 사용되는 표면처리기법이다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 니켈과 금을 도금하는 방식인데, 이 도금 프로세스가 매우 엄격하다. 도금이 um 단위로 진행되는데, 이</span><span style="font-family: 돋움, Dotum;">&nbsp;두께가 맞지 않으면 블랙패드/블랙니켈 (패드에 솔더링이 불가능해지는 현상), 부식 및 열내구성 하락 문제가 생길 수 있다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 알루미늄 와이어 본딩이 가능하다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- RF 신호가 손실된다고 한다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;"><br /></span></p>
<p style="padding: 0px; line-height: 2.2;"><b><span style="font-family: 돋움, Dotum;">1-5-4. 시장에 따른 표면 처리 분류</span></b><span style="font-family: 돋움, Dotum;">&nbsp;</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;로우엔드 컨슈머 : HASL, OSP</span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;하이엔드 컨슈머 : ENIG, 은, OSP</span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;데이터/텔레콤 : 은, OSP, ENIG</span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;자동차 : 은, OSP, 치환주석&nbsp;</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;의료용 : ENIG, ENEPIG, 은</span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;항공우주, 방위, 고성능장치 : HASL, 치환주석, ENIG, ENEPIG</span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;</span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;"><br /></span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;"><br /></span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2;"><span class="se_fs_T3"><br /></span></p>
<p align="center" style="padding: 0px; line-height: 2.2; text-align: center;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-size: 14pt; font-family: 돋움, Dotum;"><b>2. 배경지식</b></span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-size: 11pt; font-family: 돋움, Dotum;"><b>2-1. 주파수와 파장길이의 관계</b></span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2;"><span class="se_fs_T3"><img src="https://blogfiles.pstatic.net/MjAxODA2MjVfNjYg/MDAxNTI5OTM3MTYyNDI3.kKSiRBfyT9v_yIpvmPupoXA3sEiczTBVG7GNkQe_fT0g.47K4XqTj5QpnsvqX08GWmvgk7Sh9v-NDFxlC8Sm8G6gg.PNG.bae3421_/2018-06-24_15%3B43%3B28_3.png?type=w2" width="151" height="51" id="MjAxODA2MjVfNjYg/MDAxNTI5OTM3MTYyNDI3.kKSiRBfyT9v_yIpvmPupoXA3sEiczTBVG7GNkQe_fT0g.47K4XqTj5QpnsvqX08GWmvgk7Sh9v-NDFxlC8Sm8G6gg.PNG.bae3421_/2018-06-24_15%3B43%3B28_3.png" alt="" class="_photoImage" data-lazy-src="" style="border: none; cursor: pointer;" /></span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;파장 길이 (Lambda) = 파장 속도 (v) / 주파수 (f)</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;주파수 (f) = 파장 속도 (v) / 파장 길이 (Lambda)</span></p>
<p style="padding: 0px; line-height: 2;"><br /></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- 이때, 파장 속도는 아래의 표를 따른다.</span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2;"><span class="se_fs_T3"><span class="se_fs_T3"></span></span></p>
<table style="table-layout: fixed; border-width: 0.28pt; border-style: solid; border-color: #000000;">
   <tbody>
      <tr>
         <td valign="middle" style="word-break: break-all; width: 129.17pt; height: 11.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum; font-weight: bold; font-size: 9pt;">진공</span><span lang="EN-US" style="letter-spacing: 0pt; font-weight: bold; font-size: 9pt; font-family: 돋움, Dotum;">/</span><span style="font-family: 돋움, Dotum; font-weight: bold; font-size: 9pt;">공기 중 빛</span><span lang="EN-US" style="letter-spacing: 0pt; font-weight: bold; font-size: 9pt; font-family: 돋움, Dotum;">/</span><span style="font-family: 돋움, Dotum; font-weight: bold; font-size: 9pt;">전파 속도</span></p>
            </td>
         <td valign="middle" style="word-break: break-all; width: 100.86pt; height: 11.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2;"><span lang="EN-US" style="letter-spacing: 0pt; font-size: 9pt; font-family: 돋움, Dotum;">299,792,458m/s</span></p>
            </td>
         </tr>
      <tr>
         <td valign="middle" style="word-break: break-all; width: 129.17pt; height: 12.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum; font-weight: bold;">물 속 빛속도</span></p>
            </td>
         <td valign="middle" style="word-break: break-all; width: 100.86pt; height: 12.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2;"><span lang="EN-US" style="letter-spacing: 0pt; font-family: 돋움, Dotum;">224,849,965m/s</span></p>
            </td>
         </tr>
      <tr>
         <td valign="middle" style="word-break: break-all; width: 129.17pt; height: 12.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum; font-weight: bold;">공기중 음속</span></p>
            </td>
         <td valign="middle" style="word-break: break-all; width: 100.86pt; height: 12.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2;"><span lang="EN-US" style="letter-spacing: 0pt; font-family: 돋움, Dotum;">340m/s</span></p>
            </td>
         </tr>
      <tr>
         <td valign="middle" style="word-break: break-all; width: 129.17pt; height: 12.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum; font-weight: bold;">물속 음속</span></p>
            </td>
         <td valign="middle" style="word-break: break-all; width: 100.86pt; height: 12.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2;"><span lang="EN-US" style="letter-spacing: 0pt; font-family: 돋움, Dotum;">1600m/s</span></p>
            </td>
         </tr>
      </tbody>
   </table>
<p style="padding: 0px; line-height: 1.5;"><br /></p>
<p style="padding: 0px; line-height: 2.2;">&nbsp;- 주파수 별 대략적인 파장 길이는 아래와 같다.</p>
<p style="padding: 0px; line-height: 2.2;"><img src="https://blogfiles.pstatic.net/MjAxODA2MjZfMTcy/MDAxNTI5OTM5NDM5MDY1.tDP77xXgPQz_3yf_Sa_TxGa9Hj0fxiBNX9IZ6h3xwEIg.MvQFlWzDP9OZ64KOf9EgRaIMW87yWDmXFjx8hlpxkH4g.JPEG.bae3421_/%EC%A3%BC%ED%8C%8C%EC%88%98%EC%9D%98_%ED%8C%8C%EC%9E%A5.jpg?type=w2" width="208" height="163" id="MjAxODA2MjZfMTcy/MDAxNTI5OTM5NDM5MDY1.tDP77xXgPQz_3yf_Sa_TxGa9Hj0fxiBNX9IZ6h3xwEIg.MvQFlWzDP9OZ64KOf9EgRaIMW87yWDmXFjx8hlpxkH4g.JPEG.bae3421_/%EC%A3%BC%ED%8C%8C%EC%88%98%EC%9D%98_%ED%8C%8C%EC%9E%A5.jpg" alt="" class="_photoImage" data-lazy-src="" style="border: none; cursor: pointer;" />&nbsp;</p>
<p style="padding: 0px; line-height: 2;"><span class="se_fs_T3"><br /></span></p>
<p style="padding: 0px; line-height: 2;"><span class="se_fs_T3"><br /></span></p>
<p style="padding: 0px; line-height: 2;"><span class="se_fs_T3"><br /></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-size: 11pt; font-family: 돋움, Dotum;"><b>2-2. EMC</b></span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><b><span style="font-family: 돋움, Dotum;"><br /></span></b></p>
<p style="padding: 0px; line-height: 2.2;"><b><span style="font-family: 돋움, Dotum;">2-2-1. 전자기장</span></b></p>
<p style="padding: 0px; line-height: 2.2;"><b><span style="font-family: 돋움, Dotum;">&nbsp;전기장 (Electric Field)</span></b></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp; - 전하, 전압으로 인한 전기력이 미치는 공간을 의미한다.</span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><b><span style="font-family: 돋움, Dotum;">&nbsp;자기장 (Magnetic Field)</span></b></span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp; - 자성이나 전류, 전기장 등으로 인한&nbsp;자기력이 미치는 공간을 의미한다.</span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><b><span style="font-family: 돋움, Dotum;">&nbsp;전자기장 (Electro-Magnetic Field : 전기자기장)</span></b></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 전기장과 자기장을 포함하는 개념이다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 전기장, 자기장의 각각 힘, 전속밀도, 자속밀도는 서로 상호작용을 하므로, 이 둘을 아울러 전자기장이라고 정리해 부른다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><b><span style="font-family: 돋움, Dotum;">&nbsp;전자파 (Electro-Magnetic Radiation : 전자기복사)</span></b></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 가시광선, 적외선, 자외선, 전파 등, 전자기장의 변동이 파동으로써 공간을 통해 전파되는 현상이다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;"><br /></span></p>
<p style="padding: 0px; line-height: 2.2;"><b><span style="font-family: 돋움, Dotum;">2-2-2. EMC/EMI/EMS</span></b></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;"><b>&nbsp;EMC (Electro-Magnetic Compatibility&nbsp;: 전자환경적합성</b>&nbsp;/ 전자기적양립성 / 전자파적합성)</span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- EMI(주는측)와 EMS(받는측)를 포함하는 개념이다.</span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- 자체 전자파 방출을 최소한으로 하는 동시에(EMI), 외부 전자파 유입에 충분한 면역을 가져야 한다(EMS).</span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><b><span style="font-family: 돋움, Dotum;">&nbsp;EMI (Electro-Magnetic Interference</span><span style="font-family: 돋움, Dotum;">&nbsp;: 전자파장해)</span></b></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 자체 전자파 방출을 최소화 하는 능력이다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 이때, 장해는 장애의 반대말로 가해자 입장에서 불편을 끼치는 것을 의미한다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><b><span style="font-family: 돋움, Dotum;">&nbsp;EMS (Electro-Magnetic Susceptibility</span><span style="font-family: 돋움, Dotum;">&nbsp;: 전자파감응성</span></b><span style="font-family: 돋움, Dotum;">&nbsp;/ 전자파내성)</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 외부 전자파의 유입에 대한 면역 능력이다.</span></p>
<p style="padding: 0px; line-height: 2;"><br /></p>
<p style="padding: 0px; line-height: 2;"><br /></p>
<p style="padding: 0px; line-height: 2;"><br /></p>
<p style="padding: 0px; line-height: 2;"><br /></p>
<p style="padding: 0px; line-height: 2.2;"><b><span style="font-size: 11pt; font-family: 돋움, Dotum;">2-3. 노이즈 분류</span></b></p>
<p style="padding: 0px; line-height: 2.2;"><b><span style="font-family: 돋움, Dotum;"><br /></span></b></p>
<p style="padding: 0px; line-height: 2.2;"><b><span style="font-family: 돋움, Dotum;">2-3-1. 전달 방식에 따른 노이즈 분류</span></b></p>
<p style="padding: 0px; line-height: 2.2;"><b><span style="font-family: 돋움, Dotum;">&nbsp;전도성 노이즈 (CE,&nbsp;</span><span style="font-family: 돋움, Dotum;">Conducted Emission Noise)</span></b></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 전력선이나 신호선, 그리고</span><span style="font-family: 돋움, Dotum;">&nbsp;PCB 선로 등, 낮은 임피던스의 전도체를 타고 전달받은, 30MHz 이하의 저주파 노이즈다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 비교적&nbsp;</span><span style="font-family: 돋움, Dotum;">칩입경로가 확실하고, 해결하기가 쉽다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><b><span style="font-family: 돋움, Dotum;">&nbsp;방사성 노이즈 (RE, Radiated Emission Noise)</span></b></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 자유 공간으로부터 전자파 형태로 전달받은, 30MHz 이상의 고주파 노이즈다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 넓은 영역에 걸쳐 피해를 주기 때문에, 비교적 해결하기 어렵다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 전자파 방사량은 주파수의 2승에 비례한다. 따라서 특히 OSC의 경우 클럭 주파수가 높을 수록 방사 노이즈가 강해진다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><b><span style="font-family: 돋움, Dotum;"><br /></span></b></p>
<p style="padding: 0px; line-height: 2.2;"><b><span style="font-family: 돋움, Dotum;">2-3-2. 원인에 따른 노이즈 분류</span></b></p>
<p style="padding: 0px; line-height: 2.2;"><b><span style="font-family: 돋움, Dotum;">&nbsp;신호에 의한 노이즈</span></b></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 교류 전원과 같은 강한 신호가, 데이터케이블 등 원치않은 장소에 전달되어 생기는 노이즈다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;"><b>&nbsp;인덕턴스에 의한 노이즈</b></span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 릴레이, 모터, 스위치 등의 인덕턴스로 인한 역기전압 등의 노이즈이다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;"><b>&nbsp;공진회로에 의한 노이즈</b></span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 공진이 무선통신 등의 본래 용도가 아닌, 원치 않은 때에 발생하여 생긴 노이즈다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;"><b>&nbsp;임피던스 부정합에 의한 노이즈</b></span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 임피던스 부정합 경계점에서 발생된 반사파가 원래 파형과&nbsp;</span><span style="font-family: 돋움, Dotum;">합성되어 생기는 노이즈이다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="color: #ff0000; font-family: 돋움, Dotum;">(<b>인덕턴스</b>&nbsp;: 도선이 흐르는 전류의 크기가 변할 때 발생되는 유도자기장의 정도)</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="color: #ff0000; font-family: 돋움, Dotum;">(<b>공진</b>&nbsp;: 비슷한 주파수가 마날 때 큰 전류나 높은 전압 등을 발생시키는 현상)&nbsp;</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="color: #ff0000; font-family: 돋움, Dotum;">(<b>반사파</b>&nbsp;: 선로 중간에서 임피던스가 바뀔 경우, 그 경계점에서 다시 되돌아가는 신호)</span></p>
<p style="padding: 0px; line-height: 2;"><span class="se_fs_T3"><br /></span></p>
<p style="padding: 0px; line-height: 2;"><span class="se_fs_T3"><br /></span></p>
<p style="padding: 0px; line-height: 2;"><span class="se_fs_T3"><br /></span></p>
<p style="padding: 0px; line-height: 2;"><span class="se_fs_T3"><br /></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-size: 11pt; font-family: 돋움, Dotum;"><b>2-4. 임피던스 (Impedance)</b></span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;"><b><br /></b></span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;"><b>2-4-1. 임피던스</b></span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 임피던스는 Z로 표시하며, 그 단위는&nbsp;</span><span style="font-family: 돋움, Dotum; letter-spacing: 0pt;">Ω이다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum; letter-spacing: 0pt;">&nbsp;- 주파수 성분을 갖고있는 저항으로, 주파수에 따라 저항치(임피던스)는 변한다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum; letter-spacing: 0pt;">&nbsp;- 전파 지연이 없는 균일 전송선로 상의 매 지점에서의 전류 대 전압 비를 말한다.</span></p>
<p style="padding: 0px; line-height: 2;"><span style="font-family: 돋움, Dotum; letter-spacing: 0pt;"><img src="https://blogfiles.pstatic.net/MjAxODA2MjVfMTg2/MDAxNTI5OTM4MjM0MTMz.GmD8u3CJMPQRgo5FAo00IpytvyAwH2-GC7ijvFhwkEog.kpk3AXCsr0hJ8MHG7KtBDUUCTvtimDm2S8-Ti2PKcLgg.PNG.bae3421_/2018-06-24_15%3B43%3B28_4.png?type=w2" width="216" height="64" id="MjAxODA2MjVfMTg2/MDAxNTI5OTM4MjM0MTMz.GmD8u3CJMPQRgo5FAo00IpytvyAwH2-GC7ijvFhwkEog.kpk3AXCsr0hJ8MHG7KtBDUUCTvtimDm2S8-Ti2PKcLgg.PNG.bae3421_/2018-06-24_15%3B43%3B28_4.png" alt="" class="_photoImage" data-lazy-src="" style="border: none rgb(0, 0, 0); cursor: pointer;" /></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- 수식에서 볼수 있듯이, 임피던스는 저항(R), 용량성/유도성리액턴스(L), 캐패시턴스(C)의 조합으로 발생한다.</span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;"><b><br /></b></span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;"><b>2-4-2. 임피던스의 증감 조건과 목적</b></span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- PCB에서 선로의 임피던스는 배선폭, 배선두께, 절연두께, 회로형태, 유전율 등에 따라 결정된다.</span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- 임피던스의 감소 조건은 배선폭/두께 증가, 절연간격 감소, 바이패스/디커플링 캐패시터가 있다.</span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- 임피던스의 증가 조건은 레진함량/절연상수 증가가 있다.</span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3"><span class="se_fs_T3" style="font-family: 돋움, Dotum;">&nbsp;- 임피던스의 제어 목적은 반사파제거, 크로스토크최소화, 종단방법 및 그 값 산출에 있다.</span></span></span></span></span></span></p>
<p style="padding: 0px; line-height: 2.2;"><b><span style="font-family: 돋움, Dotum;"><br /></span></b></p>
<p style="padding: 0px; line-height: 2.2;"><b><span style="font-family: 돋움, Dotum;">2-4-3. 특성 임피던스</span></b></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 전송 선로에서 가지는 임피던스로, 어떤 특성을 가진다기보다는 소자/회로 간 호환성을 가지기 위한 기준점의 의미가 더 강하다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 예로, 모든 RF파트의 입력/출력단을 50</span><span style="font-family: 돋움, Dotum;">Ω으로 통일하여, 임피던스 정합 없이 바로 연결해도 반사파 등으로 인한 전력전달효율을 잃지 않게 하는것이 있다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 입력/출력 간 임피던스 차이가 클수록 반사파가 생기고 전력전달효율이 떨어진다. 이는 신호증폭도감소, 잡음여유감소를 의미한다.</span></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- 일반적인 회로에서는 밸런스가 잡힌 50</span><span style="font-family: 돋움, Dotum;">Ω을 쓰고, 안테나의 경우 전력전달보다 신호왜곡 최소화를 중점으로 한 75</span><span style="font-family: 돋움, Dotum;">Ω을 주로 사용한다.</span></p>
<p style="padding: 0px; line-height: 2;"><br /></p>
<p style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;">&nbsp;- PCB 트레이스의 임피던스 값은 아래 표를 참조한다.</span></p>
<p style="padding: 0px; line-height: 2;"><span class="se_fs_T3"><span class="se_fs_T3"></span></span></p>
<table style="table-layout: fixed; border-width: 0.28pt; border-style: solid; border-color: #000000;">
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         <td valign="middle" style="word-break: break-all; width: 59.53pt; height: 12.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;"></span><span style="font-family: 돋움, Dotum;">&nbsp;</span><span style="font-family: 돋움, Dotum;"></span></p>
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         <td colspan="4" valign="middle" style="word-break: break-all; width: 238.12pt; height: 12.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2; width: 357.406px;"><span lang="EN-US" style="letter-spacing: 0pt; font-family: 돋움, Dotum;">W=1mm (4mil)</span></p>
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         <td colspan="3" valign="middle" style="word-break: break-all; width: 178.59pt; height: 12.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2; width: 264.406px;"><span lang="EN-US" style="letter-spacing: 0pt; font-family: 돋움, Dotum;">W=3mm (15.7mil)</span></p>
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         <td valign="middle" style="word-break: break-all; width: 59.53pt; height: 12.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2;"><span style="font-family: 돋움, Dotum;"></span><span style="font-family: 돋움, Dotum;">&nbsp;</span><span style="font-family: 돋움, Dotum;"></span></p>
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         <td valign="middle" style="word-break: break-all; width: 59.53pt; height: 12.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2;"><span lang="EN-US" style="letter-spacing: 0pt; font-family: 돋움, Dotum;">L=1cm</span></p>
            </td>
         <td valign="middle" style="word-break: break-all; width: 59.53pt; height: 12.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2;"><span lang="EN-US" style="letter-spacing: 0pt; font-family: 돋움, Dotum;">L=3cm</span></p>
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         <td valign="middle" style="word-break: break-all; width: 59.53pt; height: 12.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2;"><span lang="EN-US" style="letter-spacing: 0pt; font-family: 돋움, Dotum;">L=10cm</span></p>
            </td>
         <td valign="middle" style="word-break: break-all; width: 59.53pt; height: 12.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2;"><span lang="EN-US" style="letter-spacing: 0pt; font-family: 돋움, Dotum;">L=30cm</span></p>
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         <td valign="middle" style="word-break: break-all; width: 59.53pt; height: 12.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2;"><span lang="EN-US" style="letter-spacing: 0pt; font-family: 돋움, Dotum;">L=3cm</span></p>
            </td>
         <td valign="middle" style="word-break: break-all; width: 59.53pt; height: 12.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2;"><span lang="EN-US" style="letter-spacing: 0pt; font-family: 돋움, Dotum;">L=10cm</span></p>
            </td>
         <td valign="middle" style="word-break: break-all; width: 59.53pt; height: 12.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2;"><span lang="EN-US" style="letter-spacing: 0pt; font-family: 돋움, Dotum;">L=30cm</span></p>
            </td>
         </tr>
      <tr>
         <td valign="middle" style="word-break: break-all; width: 59.53pt; height: 12.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2;"><span lang="EN-US" style="letter-spacing: 0pt; font-family: 돋움, Dotum;">10MHz</span></p>
            </td>
         <td valign="middle" style="word-break: break-all; width: 59.53pt; height: 12.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2;"><span lang="EN-US" style="letter-spacing: 0pt; font-family: 돋움, Dotum;">0.44</span><span style="font-family: 돋움, Dotum; letter-spacing: 0pt;">Ω</span></p>
            </td>
         <td valign="middle" style="word-break: break-all; width: 59.53pt; height: 12.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2;"><span lang="EN-US" style="letter-spacing: 0pt; font-family: 돋움, Dotum;">1.7</span><span style="font-family: 돋움, Dotum; letter-spacing: 0pt;">Ω</span></p>
            </td>
         <td valign="middle" style="word-break: break-all; width: 59.53pt; height: 12.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2;"><span lang="EN-US" style="letter-spacing: 0pt; font-family: 돋움, Dotum;">7.3</span><span style="font-family: 돋움, Dotum; letter-spacing: 0pt;">Ω</span></p>
            </td>
         <td valign="middle" style="word-break: break-all; width: 59.53pt; height: 12.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.2;"><span lang="EN-US" style="letter-spacing: 0pt; font-family: 돋움, Dotum;">26</span><span style="font-family: 돋움, Dotum; letter-spacing: 0pt;">Ω</span></p>
            </td>
         <td valign="middle" style="word-break: break-all; width: 59.53pt; height: 12.82pt; padding: 1.41pt 5.1pt; border-width: 0.28pt; border-style: solid; border-color: #000000;">
            <p class="0" style="padding: 0px; line-height: 2.