自动布局布线程序

功述描述了用于规划芯片的自动布局布线程序。其特点是在单元电路版图实现之前进行布局布线以及布线是在单元内部进行，不存在专门的布线通道。这种布图模式，以多端网连接模型作为布局布线的连接模型，并以布线均匀作为主要的目标函数。 整个程序模块分为矩阵网格规划和布局，总体布线，端口分配三部分。在布局中采用最小切割算法。初始布线以布线均匀，连线长度最短为目标，并采用一个基于布线均匀的“重心“算法。通过再布线和通

AN AUTOMATIC PLACEMENT AND ROUTING PROGRAM

An automatic placement and routing program for chip planning isdescribed in this paper.Its features are:the placement and routing are realizedbefore realizing circuit layout of a cell and the routing is realized in the internal ofthe cell.There is not special routing channel.In this type of layout model,multi-port connection model is taken for the connection model of placement and routingand at the same time homogeneous routing is taken for main objective function.The.program module can be divided into three parts:matrix grid planning andplacement,global routing,and port assigning.A min-cut algorithm is used inplacement.In initial routing,homogeneous routing and minimal wiring length aretaken for objective,and a center of gravity algorithm based on homogeneous routingis used.Through rerouting and channel expanding,the routing can be completed100%.The results of experiment with some examples are satisfactory.