摘要
本文简述了一种分级式的自下而上结群和自上而下分划定位相结合的全定制方式的积木块(building block)布局及平面规划(floorplanning)系统.本方法基于积木块的尺寸、形状、连接状况、引线位置以及芯片引线端等的要求逐级优化组合若干种积木块组,并且根据工艺条件进行了布线区面积估计,以便得到较好的布局结果.如果积木块的尺寸或其长宽比可以改变,则本系统可改变其尺寸及形状从而优化布局结果.由于采用了多种有效的实用方法,并把它们有机地统一在系统中,因此使布局能在基本满足用户要求的条件下,做到和布线结果基本匹配.实验结果表明,这种方法是令人满意的.
A hierarchical placement and floorplanning algorithm,combining the goal of blocks ar-rangement and orientation at top-down manner with the one at bottom-up clustering, are desc-ribed. Based on the size, shapes, pin positions, connective relations of the blocks and pad posi-tions of the chip, several optimizations of block groups with routing area estimated accordingto technology conditions at each level are created so that to reach the optimal placement. If theflexible blocks are included, the system can be optimized by resizing these blocks constrainedto their areas or aspect ratio within their possible numbers. The placement and floorplanningresult can be matched with the one of routing due to many effective methods in the system.Some results and comparisons with other methods are also given.
关键词
VLSI
积木块
平面规划
布线
Building block layout
Floorplanning
Custom and ASIC VLSI design
