基于Single—Sequence布图规划线长约束问题的研究

The Length Constraict of Floorplanning Based on Single- Sequence

布图规划是VLSI设计中非常重要的步骤。Single—Sequenc是一种非常有用的表示布图的编码方法。在实际的布图规划中，由于线长对芯片性能有较大的影响，因此为了使芯片的整体性能达到最优，考虑线长因素，使线长尽可能短。该论文提出了在用模拟退火算法寻求最优布图的同时，通过对算法加以改进，考虑线长约束条件，有效地解决了布图规划的线长约束问题。

The design of floorplanning is the most important step in the VLSI design. Single- Sequence is a useful code representation. In a actual floorplan, because the length has great influence to the chip＇s ruction, so we should make the length as short as possible,considering the length factor,to make the whole function of the chip attain superior. In this paper, we propose a method for solving the length constraint problem and we seek the optimum solution by SA （Simulated Annealing） algorithm,which has been improved for the length constraint. It is proved that this method is useful and effiicient in placement design with length constraint.