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4.6.2 Heat sink-Contact 散热片――接触片 arget-Class 1,2,3 目标——等级 1,2,3 · Component and heatsink are in full contact with the mounting surface. 组件和散热片与安装表面完全接触 · Hardware meets specified attachment requirements. 部件满足规定的接触要求。 Figure图4-64 1. Heat sink 散热片 Acceptable-Class 1,2,3 可接受的——等级 1,2,3 · Component not flush. 组件不平齐 · Minimum 75% contact with mounting surface. 至少有75%与安装表面接触 · Hardware meets mounting torque requirements if specified. 如果有规定,部件满足安装的转距要求 Figure图4-65 1. Gap 2. Heat sink 间隙散热片 Defect-Class 1,2,3 . 缺点——等级 1,2,3 · Component is not in contact with mounting surface. 组件没有接触到安装表面 · Hardware is loose and can be moved. 部件松弛可以移动。 Figure图4-66 1. Heat sink 2. Gap 散热片间隙 5.1 Orientation 方向 5.1.1 Orientation-Horizontal 方向——水平 Target-Class 1,2,3 目标——等级 1,2,3 •Components are centered between their lands. 组件位于焊盘中央 •Component markings are discernible. 组件标识清晰可见 •Nonpolarized components are oriented so that markings all read the same way (left-to-right or top-to-bottom). Figure图5-1 无极性组件的方向应使其标识都能按同样方式进行辨识 (从左到右或从上到下) . Acceptable-Class 1,2,3 可接受的——等级 1,2,3 •Polarized and multilead components are oriented correctly. 有极性和多引脚的组件应按正确方向安装。 •When hand polarization symbols are discernible. 当手工成型与手插件时,极性符号可以辨识。 •All components are as specified and terminate to Figure图 5-2 correct lands. 所有组件都符合规定并连接到正确的焊盘上。 •Nonpolarized components do not need to be oriented so that markings all read the same way(left-to right or top to-bottom). 无极性的组件不需要按同样的方向,只要标识可按相同方向辨识即可(从左到右或从上到下). 5.1.1 Orientation-Horizontal(cont.) 方向——水平(续) formed and hand-inserted, Defect-Class 1,2,3 缺点——等级1,2,3 •Component is not as specified (Wrong part). 组件不符合规定(组件错误) •Component not mounted in correct holes. 组件没有安装在正确的孔中。 •Polarized component mounted backwards. 有极性组件安装方向相反。 •Multileaded component not oriented correctly. Figure图 5-3 多引脚组件的安装方向不正确。 5.1.2 Orientation-Vertical . 本文来源:https://www.dywdw.cn/82e16fa72b4ac850ad02de80d4d8d15abe23007d.html