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  <title>最值得关注的pcb抄板，pcb设计。</title>
  <link>http://blog.tom.com/pcbchaobanmxh</link>
  <description><![CDATA[深圳龙人计算机pcb抄板工作室 ]]></description>
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		<title><![CDATA[ 三种小型大电流PCB连接器市场看好  电子器件分销商乐于进货 ]]></title>
		<link>http://blog.tom.com/pcbchaobanmxh/article/5884.html</link>
		<description><![CDATA[ <p style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: center" align="center">&nbsp;</p>
<p style="MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 21pt; mso-char-indent-count: 2.0"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">全球最大的电子器件分销商之一，</span><span lang="EN-US"><font face="Times New Roman">Mouser Electronics</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">日前宣布，其正在进货</span><span lang="EN-US"><font face="Times New Roman">Amphenol Industria</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">的三种小型大电流</span><span lang="EN-US"><font face="Times New Roman">lRADSOK PCB</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">连接器。</span><span lang="EN-US"><font face="Times New Roman">Amphenol Industria</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">是</span><span lang="EN-US"><font face="Times New Roman">Amphenol Corporation</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">旗下部门，是一家互连系统供应商。这种新型的小型大电流</span><span lang="EN-US"><font face="Times New Roman">PCB</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">连接器，是经过精心的</span><span lang="EN-US" style="COLOR: #333333"><a href="http://www.sipcb.net/pcb/pcbsheji_list_47_1.htm"><span style="COLOR: #333333"><font face="Times New Roman">PCB</font></span><span lang="EN-US" style="COLOR: #333333; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><span lang="EN-US">设计</span></span></a></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">而研发出来的，通过了严格的</span><span lang="EN-US"><font face="Times New Roman">pcb</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">设计测试，才流向市场，很受市场欢迎，这种新型的</span><span lang="EN-US"><font face="Times New Roman">PCB</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">连接器有着突出的性能。</span></p>
<p style="MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 21pt; mso-char-indent-count: 2.0"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">这几款新型</span><span lang="EN-US"><font face="Times New Roman">PowerBlok</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">、</span><span lang="EN-US"><font face="Times New Roman">RADSERT</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">和</span><span lang="EN-US"><font face="Times New Roman">PGY</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">连接器系列适用于到印刷电路板</span><span lang="EN-US"><font face="Times New Roman">(PCB)</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">的电流单点连接。这些连接器采用</span><span lang="EN-US"><font face="Times New Roman">RADSOK</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">来提高电流和</span><span lang="EN-US"><font face="Times New Roman">/</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">或安培，消除了螺纹连接的故障，提高了可靠性、灵活性和电路板设计内部的可用表面空间。</span></p>
<p style="MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 21pt; mso-char-indent-count: 2.0"><span lang="EN-US"><font face="Times New Roman">PowerBlok</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">连接器采用</span><span lang="EN-US"><font face="Times New Roman">12.7mmx12.7mm</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">的小型封装，可向电路板提供最高达</span><span lang="EN-US"><font face="Times New Roman">70A</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">的电流。该款连接器的底板电源接口使用兼容管脚，压接到电路板上，可以保证稳固的连接和均匀的信号流。</span><span lang="EN-US"><font face="Times New Roman">PowerBlok</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">采用径向设计以确保多点接触，并采用防接触外壳保证操作更加安全。</span></p>
<p style="MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 21pt; mso-char-indent-count: 2.0"><span lang="EN-US"><font face="Times New Roman">RADSERT</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">连接器的尺寸包括</span><span lang="EN-US"><font face="Times New Roman">2.4mm</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">和</span><span lang="EN-US"><font face="Times New Roman">3.6mm</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">，可分别传输最高达</span><span lang="EN-US"><font face="Times New Roman">35A</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">和</span><span lang="EN-US"><font face="Times New Roman">70A</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">的电流。</span><span lang="EN-US"><font face="Times New Roman">RADSERT</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">的占位面积最小，可以解放最多的表面空间以提高设计灵活性。</span><span lang="EN-US"><font face="Times New Roman">RADSERT</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">允许设计师利用电路板及其元件上面的汇流排获得电源。标准的</span><span lang="EN-US"><font face="Times New Roman">RADSERT</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">适用的电路板厚度为</span><span lang="EN-US"><font face="Times New Roman">6.35mm</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">±</span><span lang="EN-US"><font face="Times New Roman">0.0635mm</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">，针对特殊的应用可以提供定制尺寸。</span></p>
<p style="MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 21pt; mso-char-indent-count: 2.0"><span lang="EN-US"><font face="Times New Roman">PGY</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">连接器的尺寸包括</span><span lang="EN-US"><font face="Times New Roman">3.6mm</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">和</span><span lang="EN-US"><font face="Times New Roman">5.7mm</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">，可分别提供最高达</span><span lang="EN-US"><font face="Times New Roman">70A</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">及</span><span lang="EN-US"><font face="Times New Roman">120A</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">的电流，以最小封装提供最大电流。该款连接器允许设计师在不影响电路板所需功率的情况下，根据需求降低其设计的尺寸与重量。</span></p>
<p style="MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 21pt; mso-char-indent-count: 2.0"><span lang="EN-US"><font face="Times New Roman">RADSOCK PCB</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">连接器符合</span><span lang="EN-US"><font face="Times New Roman">RoHS</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">标准，可以采用手工</span><span lang="EN-US"><font face="Times New Roman">(</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">压接</span><span lang="EN-US"><font face="Times New Roman">)</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">或者回流焊工艺安装，不需要额外的导线和特殊的压接工具。</span></p>
<p style="MARGIN: 0cm 0cm 0pt"><span lang="EN-US"><font face="Times New Roman">&nbsp;</font></span></p> ]]></description>
		<eb:creationDate>2008-09-25 11:48:56</eb:creationDate>
		<eb:modificationDate></eb:modificationDate>
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		<title><![CDATA[ Pcb抄板中的挠性覆铜板的保护涂层分类比较 ]]></title>
		<link>http://blog.tom.com/pcbchaobanmxh/article/5844.html</link>
		<description><![CDATA[ <p style="MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 21pt; mso-char-indent-count: 2.0"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><span lang="EN-US"><font face="Times New Roman">Pcb</font><span style="COLOR: red"><a href="http://www.dmpcb.cn/"><span lang="EN-US" style="COLOR: red; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><span lang="EN-US">抄板</span></span></a></span></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">中的保护覆盖层就是一种覆盖在挠性</span><span lang="EN-US"><font face="Times New Roman">pcb</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">板导体一面上的永久的绝缘薄膜或一种涂层</span><span lang="EN-US"><font face="Times New Roman">(</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">当然焊盘处不需要保护涂层</span><span lang="EN-US"><font face="Times New Roman">)</font></span> <span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">，这种保护涂层能防止电路受潮，污染以及有其他形式的损害，同时也可减少导体在挠曲过程中的所产生的不利应力。下面就对几种不同类型的保护涂层进行评价和比较。</span></span></p>
<p style="MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 21pt; mso-char-indent-count: 2.0"><span lang="EN-US"><font face="Times New Roman">(1)</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">覆盖膜，它是一种由涂胶的绝缘薄膜构成的材料。覆盖膜可以依据电路板的结构预先被钻孔或冲孔，在加压和加热的情况下，保护膜可以定位地覆盖到线路上。在</span><span lang="EN-US" style="COLOR: red"><a href="http://pcbxhm.591blog.com/"><span style="COLOR: red"><font face="Times New Roman">pcb</font></span></a></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">抄板中，覆盖膜中的介电基材厚度应与基材中介电材料的厚度大约相同或稍薄一些，并且胶粘剂层厚度与被覆盖的金属箔的厚度也大致相同或稍薄一些，从而在挠曲过程中减少导体的应力。最典型和最通常使用的覆盖膜的结构是涂有聚醋树脂的聚酯薄膜、涂有丙烯酸胶粘剂或环氧胶粘剂的聚酰亚胺薄膜。覆盖膜最通常便使用的形式为单面，当制造多层挠性线路板时也使用双面涂胶覆盖膜。</span></p>
<p style="MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 21pt; mso-char-indent-count: 2.0"><span lang="EN-US"><font face="Times New Roman">(2)</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">液体涂料保护层，它一般是由聚酯胶液或液态的聚酯制成的。该材料是由丝网印刷到线路板上的，并通过红外光加热或紫外线来固化，以形成一层永久不变的，薄的和不易磨损的保护涂层。这种液体涂料保护层在</span><span lang="EN-US" style="COLOR: red"><a href="http://www.lrpcb.cn/"><span style="COLOR: red"><font face="Times New Roman">pcb</font></span><span lang="EN-US" style="COLOR: red; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><span lang="EN-US">抄板</span></span></a></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">中十分常见，它主要是起到保护电路板的作用。</span></p>
<p style="MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 21pt; mso-char-indent-count: 2.0"><span lang="EN-US"><font face="Times New Roman"><span style="mso-spacerun: yes">&nbsp;</span>(3)</font></span> <span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">干膜光敏屏蔽层，干膜光敏屏蔽层是一种可由照相工艺制成覆盖膜形状尺寸的方法。这种薄膜是镶嵌在纸基上的，使用加热，加压及真空的方法层压到已腐蚀好的挠性印制</span><span lang="EN-US"><font face="Times New Roman">pcb</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">板上以实现一个严密的均匀的密封层。然后，除焊孔或其他不需保护的表面不暴露以外，将他们通过照相的底片暴露于光下，薄膜在照相暴露的面上固化，从而形成覆盖层。这种方法，在</span><span lang="EN-US"><font face="Times New Roman">pcb</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">抄板中使用比较方便，有很多</span><span lang="EN-US" style="COLOR: red"><a href="http://pcbxhm.woku.com/"><span style="COLOR: red"><font face="Times New Roman">pcb</font></span><span lang="EN-US" style="COLOR: red; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><span lang="EN-US">抄板</span></span></a></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">厂商乐意使用这种保护层。</span></p>
<p style="MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 21pt; mso-char-indent-count: 2.0"><span lang="EN-US"><font face="Times New Roman">(4)</font></span> <span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">液体光敏屏蔽层液体光敏屏蔽层是用辑、棒或喷涂成形的方法在已腐蚀好的挠性</span><span lang="EN-US"><font face="Times New Roman">pcb</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">板上实现一个严密的均纯的密封层，以后采用加热或与干膜光敏屏蔽层一样的工艺进行固化。在</span><span lang="EN-US"><font face="Times New Roman">pcb</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">抄板中，这种固化比较繁琐，但效果无疑是最好的。</span></p>
<p>&nbsp;</p> ]]></description>
		<eb:creationDate>2008-09-04 11:01:28</eb:creationDate>
		<eb:modificationDate></eb:modificationDate>
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		<title><![CDATA[ Pcb抄板中的挠性覆铜板的保护涂层分类比较 ]]></title>
		<link>http://blog.tom.com/pcbchaobanmxh/article/5843.html</link>
		<description><![CDATA[ <p style="MARGIN: 0cm 0cm 0pt; TEXT-ALIGN: center" align="center">&nbsp;</p>
<p style="MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 21pt; mso-char-indent-count: 2.0"><span lang="EN-US"><font face="Times New Roman">Pcb</font><span style="COLOR: red"><a href="http://www.dmpcb.cn/"><span lang="EN-US" style="COLOR: red; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><span lang="EN-US">抄板</span></span></a></span></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">中的保护覆盖层就是一种覆盖在挠性</span><span lang="EN-US"><font face="Times New Roman">pcb</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">板导体一面上的永久的绝缘薄膜或一种涂层</span><span lang="EN-US"><font face="Times New Roman">(</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">当然焊盘处不需要保护涂层</span><span lang="EN-US"><font face="Times New Roman">)</font></span> <span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">，这种保护涂层能防止电路受潮，污染以及有其他形式的损害，同时也可减少导体在挠曲过程中的所产生的不利应力。下面就对几种不同类型的保护涂层进行评价和比较。</span></p>
<p style="MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 21pt; mso-char-indent-count: 2.0"><span lang="EN-US"><font face="Times New Roman">(1)</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">覆盖膜，它是一种由涂胶的绝缘薄膜构成的材料。覆盖膜可以依据电路板的结构预先被钻孔或冲孔，在加压和加热的情况下，保护膜可以定位地覆盖到线路上。在</span><span lang="EN-US" style="COLOR: red"><a href="http://pcbxhm.591blog.com/"><span style="COLOR: red"><font face="Times New Roman">pcb</font></span></a></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">抄板中，覆盖膜中的介电基材厚度应与基材中介电材料的厚度大约相同或稍薄一些，并且胶粘剂层厚度与被覆盖的金属箔的厚度也大致相同或稍薄一些，从而在挠曲过程中减少导体的应力。最典型和最通常使用的覆盖膜的结构是涂有聚醋树脂的聚酯薄膜、涂有丙烯酸胶粘剂或环氧胶粘剂的聚酰亚胺薄膜。覆盖膜最通常便使用的形式为单面，当制造多层挠性线路板时也使用双面涂胶覆盖膜。</span></p>
<p style="MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 21pt; mso-char-indent-count: 2.0"><span lang="EN-US"><font face="Times New Roman">(2)</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">液体涂料保护层，它一般是由聚酯胶液或液态的聚酯制成的。该材料是由丝网印刷到线路板上的，并通过红外光加热或紫外线来固化，以形成一层永久不变的，薄的和不易磨损的保护涂层。这种液体涂料保护层在</span><span lang="EN-US" style="COLOR: red"><a href="http://www.lrpcb.cn/"><span style="COLOR: red"><font face="Times New Roman">pcb</font></span><span lang="EN-US" style="COLOR: red; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><span lang="EN-US">抄板</span></span></a></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">中十分常见，它主要是起到保护电路板的作用。</span></p>
<p style="MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 21pt; mso-char-indent-count: 2.0"><span lang="EN-US"><font face="Times New Roman"><span style="mso-spacerun: yes">&nbsp;</span>(3)</font></span> <span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">干膜光敏屏蔽层，干膜光敏屏蔽层是一种可由照相工艺制成覆盖膜形状尺寸的方法。这种薄膜是镶嵌在纸基上的，使用加热，加压及真空的方法层压到已腐蚀好的挠性印制</span><span lang="EN-US"><font face="Times New Roman">pcb</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">板上以实现一个严密的均匀的密封层。然后，除焊孔或其他不需保护的表面不暴露以外，将他们通过照相的底片暴露于光下，薄膜在照相暴露的面上固化，从而形成覆盖层。这种方法，在</span><span lang="EN-US"><font face="Times New Roman">pcb</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">抄板中使用比较方便，有很多</span><span lang="EN-US" style="COLOR: red"><a href="http://pcbxhm.woku.com/"><span style="COLOR: red"><font face="Times New Roman">pcb</font></span><span lang="EN-US" style="COLOR: red; FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><span lang="EN-US">抄板</span></span></a></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">厂商乐意使用这种保护层。</span></p>
<p style="MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 21pt; mso-char-indent-count: 2.0"><span lang="EN-US"><font face="Times New Roman">(4)</font></span> <span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">液体光敏屏蔽层液体光敏屏蔽层是用辑、棒或喷涂成形的方法在已腐蚀好的挠性</span><span lang="EN-US"><font face="Times New Roman">pcb</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">板上实现一个严密的均纯的密封层，以后采用加热或与干膜光敏屏蔽层一样的工艺进行固化。在</span><span lang="EN-US"><font face="Times New Roman">pcb</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">抄板中，这种固化比较繁琐，但效果无疑是最好的。</span></p> ]]></description>
		<eb:creationDate>2008-09-04 10:59:37</eb:creationDate>
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		<title><![CDATA[ 自动测试软件软件的失效模式分类 ]]></title>
		<link>http://blog.tom.com/pcbchaobanmxh/article/5799.html</link>
		<description><![CDATA[ <p style="MARGIN: 0cm 0cm 0pt">&nbsp;</p>
<p style="MARGIN: 0cm 0cm 0pt"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">　　软件失效是指软件出现如下的状态：</span></p>
<p style="MARGIN: 0cm 0cm 0pt"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">　　</span><span lang="EN-US"><font face="Times New Roman">(1)</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">功能部件执行其功能的能力的丧失；</span></p>
<p style="MARGIN: 0cm 0cm 0pt"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">　　</span><span lang="EN-US"><font face="Times New Roman">(2)</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">系统或系统部件丧失了在规定的限度内执行所要求功能的能力；</span></p>
<p style="MARGIN: 0cm 0cm 0pt"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">　　</span><span lang="EN-US"><font face="Times New Roman">(3)</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">程序操作背离了程序需求。</span></p>
<p style="MARGIN: 0cm 0cm 0pt"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">　　在实际的软件应用中，如</span><span lang="EN-US"><a href="http://www.dmpcb.cn/"><font face="Times New Roman">pcb</font><span lang="EN-US" style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><span lang="EN-US">抄板</span></span></a></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">，电路板印制，</span><span lang="EN-US"><font face="Times New Roman">pcb</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">设计等工程项目中，按常规习惯，软件失效</span><span lang="EN-US"><font face="Times New Roman">(</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">故障</span><span lang="EN-US"><font face="Times New Roman">)</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">可分为：</span></p>
<p style="MARGIN: 0cm 0cm 0pt"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">　　</span><span lang="EN-US"><font face="Times New Roman">(1)</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">死机；软件停止输出。</span></p>
<p style="MARGIN: 0cm 0cm 0pt"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">　　</span><span lang="EN-US"><font face="Times New Roman">(2)</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">运行速度不匹配：数据接受</span><span lang="EN-US"><font face="Times New Roman">(</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">输入</span><span lang="EN-US"><font face="Times New Roman">)</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">或输出的速度与系统的需求不符。</span></p>
<p style="MARGIN: 0cm 0cm 0pt"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">　　</span><span lang="EN-US"><font face="Times New Roman">(3)</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">计算精度不够：因数据采集量不够或算法问题导致某一或某些输出参数值的计算</span></p>
<p style="MARGIN: 0cm 0cm 0pt"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">　　</span><span lang="EN-US"><font face="Times New Roman">(4)</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">精度不合要求。</span></p>
<p style="MARGIN: 0cm 0cm 0pt"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">　　</span><span lang="EN-US"><font face="Times New Roman">(5)</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">输出项缺损：缺少某些必要的输出值。</span></p>
<p style="MARGIN: 0cm 0cm 0pt"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">　　</span><span lang="EN-US"><font face="Times New Roman">(6)</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">输出项多余：软件输出了系统不期望的数据／指令。</span></p>
<p style="MARGIN: 0cm 0cm 0pt"><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">　　软件的故障模式原因，即缺陷的分类问题，可分类为需求缺陷、设计缺陷、编码缺陷、文档缺陷、管理缺陷、安装缺陷六类。</span></p> ]]></description>
		<eb:creationDate>2008-08-25 10:26:43</eb:creationDate>
		<eb:modificationDate></eb:modificationDate>
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		<title><![CDATA[ Pcb抄板中，流体力学对蚀刻液特性的影响 ]]></title>
		<link>http://blog.tom.com/pcbchaobanmxh/article/5798.html</link>
		<description><![CDATA[ <p style="MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 21pt; mso-char-indent-count: 2.0"><span lang="EN-US"><font face="Times New Roman">1</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">．蚀刻液的表面张力：因为任何物体都有一定的表面积因此液体表面就好像有一层紧缩的薄膜，这层薄膜具有一股分子级的内向吸引力，使其有收缩的趋势，为了维持这紧张的表面平衡，在表面周界上必须加一适当的和表面相切力才能使表面维持一定的面积，不再收缩，这种和表面相切的力叫表面张力。作用在表面上单位长度上的张力用符号σ表示。单位是达因</span><span lang="EN-US"><font face="Times New Roman">/</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">厘米。在</span><span lang="EN-US"><a href="http://www.pcbinf.com/"><font face="Times New Roman">pcb</font><span lang="EN-US" style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><span lang="EN-US">抄板</span></span></a></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">中蚀刻液的表面张力大小对蚀刻速率和蚀刻质量的影响，与固体表面（指铜箔表面）润湿程度有关。所谓润湿就是液体在固体表面上的贴附现象称之。也就是液体在固体表面上的形状与接触角（θ）大小有关。接触角越大，固体表面的润湿越差即亲水性越差，要维持接触角（θ）为最小锐角，就必须改变固体的表面性质。这就是说，液体表面张力越小，对固体表面的润湿性能也就越好，但是如果固体表面被沾污，即使液体表面张力小，也不会改善固体表面润湿程度。所以，要获得最隹的蚀刻质量，就必须加强对基板铜箔表面的清洁处理，改善表面性质使与蚀刻液更好的处在润湿状态。要改善液体的表面张力，还需提高作业温度，温度越高，液体的表面张力就越小，与固体的贴附就更为理想，处理的效果就好。这是由于温度升高引起物质的膨胀，增大了分子间的距离而使分子间的引力减小，所以随着溶液的温度升高，表面张力是逐渐减小的。为此，做到严格的控制工艺条件，就能够更好的改善溶液与基板铜表面的接触状态。</span></p>
<p style="MARGIN: 0cm 0cm 0pt"><span lang="EN-US"><font face="Times New Roman">&nbsp;</font></span></p>
<p style="MARGIN: 0cm 0cm 0pt; TEXT-INDENT: 21pt; mso-char-indent-count: 2.0"><span lang="EN-US"><font face="Times New Roman">2</font></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">．粘度：在</span><span lang="EN-US"><a href="http://www.pcb-ic.com/"><font face="Times New Roman">pcb</font><span lang="EN-US" style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'"><span lang="EN-US">抄板</span></span></a></span><span style="FONT-FAMILY: 宋体; mso-ascii-font-family: 'Times New Roman'; mso-hansi-font-family: 'Times New Roman'">的蚀刻过程中，随着铜的不断溶解，蚀刻液的粘度就会增加，使蚀刻液在基板铜箔表面上流动性就差，直接影响蚀刻效果。要达到理想的蚀刻液的最佳状态就要充分利用蚀刻机的功能，确保溶液的流动性。</span></p>
<p style="MARGIN: 0cm 0cm 0pt"><span lang="EN-US"><font face="Times New Roman">&nbsp;</font></span></p>
<p style="MARGIN: 0cm 0cm 0pt"><span lang="EN-US"><font face="Times New Roman">&nbsp;</font></span></p> ]]></description>
		<eb:creationDate>2008-08-25 10:25:41</eb:creationDate>
		<eb:modificationDate></eb:modificationDate>
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