IPC-A-电子产品检验国际标准

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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 formed and hand-inserted,
polarization
symbols are discernible.
当手工成型及手插件时,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)
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
方向——垂直
Target-Class 1,2,3
目标——等级 1,2,3
•Nonpolarized component markings read from
the top
down.
无极性组件的标识可以从上至下辨识
•Polarized markings are located on top.
极性标识位于顶部.
Figure图 5-4
Acceptable-Class 1,2,3
可接受的——等级 1,2,3
•Polarized part is mounted with a long ground
lead.
极性组件安装时有长的接地引脚
•Polarized marking hidden.
极性标识被隐藏起来
•Nonpolarized component markings read from bottom to top.
无极性组件标识可以从底至上辨识。

Figure图 5-5
Defect-Class 1,2,3
缺点——等级 1,2,3
•Polarized component is mounted backwards.
极性组件安装反向。

Figure图 5-6
5.2 Mounting
安装
5.2.1 Mounting-Horizontal-Axial Leaded-Supported Holes
安装——水平——轴向引脚——有支撑孔
Target-Class 1,2,3
目标——等级1,2,3
•The entire body length of the component is in
contact with the board surface.
整个组件本体长度与线路板表面完全接触
•Components required to be mounted off the
board are ,at least 1.5mm[0.059 in]from the
board surface; e.g., high heat dissipating.
需要离开线路板表面安装的组件至少要离开线路板
Figure图 5-7 平面1.5mm(0.059 in),如高散热器件.
Figure图 5-8。