原创 palce bound top DFA bound top

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Place_Bound_Top
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Used to ensure you don’t place components on top of each without getting a DRC.  This boundary% F" w4 n/ {+ Q9 B2 o
normally defines the component area which may or may not include pins of surface mount devices.
8 |4 h2 k  |! @( J" E" W& }8 jThis boundary can also be assigned a component high to be verified at the board level and checked, v4 l0 O% w/ J0 ~
to the Package_Keepout_Top boundaries or any other special component clearances.  If this boundary
$ G8 d) R. T- n4 q. Y& Gdoes not exist than it will be automatically created based on the Assembly_Top outline and the outer* }- {4 l/ B; _2 \& p  \- s* {
extents of the component pins. This boundary can only be defined at the symbol level (.dra).
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+ j: o; E3 L1 P) v  W2 j' vPlace_Bound_Top用于确保你不会在其他器件的顶部放置器件，否则报DRC。这个功能定义了器件所占区域，包括表贴器件的pins（有些不包括）。这个功能也能用来定义板级检验时的器件高度，和检查Package_Keepout_Top或其他特殊器件间距。如果这个功能不存在，它将依照Assembly_Top的边框和器件pins的向外扩展，自动创建。这个功能只能在symbol级定义（.dra）。2 i& }& B' G! M8 |3 H' y. p

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9 c; E, w8 z, w7 t8 T% ZDfa_Bound_Top
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1 L/ s" u, a) hUsed by the Real Time Design for Assembly (DFA) Analysis to check clearances between components
0 f6 I* Y9 u8 B1 C1 {driven by a Spreadsheet based matrix of components.  This boundary normally or can be different then9 H. j7 _, l; b2 g6 o0 Z! `
the traditional Place_Bound_Top boundary and it may include pins of surface mount devices.
9 |% ^6 o; O) s. q+ y) x) A5 l6 g: aIf this boundary does not exist than the DFA checks default to using the Place_Bound_Top boundary.  0 C6 q# d2 _' ^0 [

. G( d0 H; a: U1 j5 B+ J8 o. bThis boundary can only be defined at the symbol level (.dra).
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Dfa_Bound_Top
) Q# `3 G: v3 ?7 V% _8 I( J5 {在实时设计中，在器件阵列的数据表驱动下，用它在装配（DFA）分析中检查器件间距。该功能（指定所占区域）可以相同，或不同于传统的Place_Bound_Top功能，即可能包含表贴器件的pins。如果这个功能不存在，则DFA检查就默认的使用Place_Bound_Top功能（来代替）。这个功能只能在symbol级定义（.dra）。7 y; d0 t" O% Q! q. C* R* F8 ~
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Package_Keepout_Top. |7 ?! \  }0 i6 u" W
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Used to ensure you don’t violate placement keepout areas or high restricted area in a design.$ c% P, w2 g# V

* k; M$ L) X: [6 [" \This boundary can only be defined at the board level (.brd) and cannot be added to the
+ l$ c0 J% Y- ?: Lsymbol level (.dra) unless it is part of a Mechanical Symbol (.bsm)
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用于确保在设计中，你不会在keepout区或高度受限区，非法放置器件。这个功能只能在board级（.brd）定义，不能添加到symbol级（.dra），除非他是机械symbol（.bsm）的一部分。+ g$ K1 Z" }3 b  R* ~- A1 C6 t