标签: bound

http://www.cadence.com/Community/forums/p/10684/11609.aspx   Place_Bound_Top % _$ F: P" ^4 q% ` P, m) M4 `8 X- d4 W4 D2 F! I) v 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 j This 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 G does 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). 4 s( N1 B8 @6 T4 u/ K% m, P 5 E  w4 H! F8 c5 c   {6 r* E0 t' r- u! B2 ~. [ + j: o; E3 L1 P) v  W2 j' v Place_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 1 c w9 b7 z8 S2 G2 Z7 _8 c 9 c; E, w8 z, w7 t8 T% Z Dfa_Bound_Top : l' p' ~8 c+ b, S 1 L/ s" u, a) h Used 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 then 9 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: a If 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. b This boundary can only be defined at the symbol level (.dra). - C% l4 N5 x' x$ ` 9 W/ j/ j( }' s; |8 m% {4 w - f$ y; x" U: H; w; [ . p* N! b* J# ?( ^  `5 t9 } 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 ~ ' l' o2 l4 q8 _6 c3 |! Q) S3 W ! A5 [  q" A9 F' b$ v, } 4 R* X. z  ^4 L4 l' ~/ d* X % ~9 @. k  |: S: J' X, | Package_Keepout_Top . |7 ?! \  }0 i6 u" W 7 D P) e* O* o6 [$ b V 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- ?: L symbol level (.dra) unless it is part of a Mechanical Symbol (.bsm) ; E9 l  a/ D3 D* H( q0 J   c! \3 \; Z8 O, f5 K  j ) @$ X0 `6 p6 A R9 D4 V Package_Keepout_Top   Y9 o9 {4 u1 R$ d* h 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