一种改进的布局前平均线长估计算法

An improved pre-layout wire length estimation

互连长度是版图设计中的重要参数,为了改善电路的布局布线,需要对互连长度进行可靠的估计.提出了一种包含外部连接的改进线长估计算法,通过考虑最佳布局的内在特征,得出外部连接的互连长度分布和平均外部连接长度的计算公式.同时考虑外部连接和内部连接两类互连,获得了平均互连长度的解析表达式.基准电路实例表明,相对于Donath技术和改进Donath技术,利用这种算法得到的平均互连长度误差分别降低了29%和5%.

Interconnection length is an important layout property of electronic designs. A reliable interconnection length estimation is essential for improving placement and routing techniques. By considerring external interconnection, an improved prior wire length estimation method is proposed. Interconnection length distribution and average interconnection length expression for external interconnection are obtained by taking into account the inherent features of the optimal placement process. By considerring both internal and external at the same time, an analytical form for the average wire length is obtained. Experimental results for several benchmark circuits show that the new method is more accurate than the Donath and Improved Donath technique by 29% and 5% respectively.