一种快速的低压降电源/地网络设计方案

Quick design method of low IR drop P/G mesh

在税控机SoC的物理设计中,对电源/地网络的设计流程做了较大地改进,提出了一种基于布线密度的设计方法:首先根据目标电压降确定各层金属电源/地线的布线密度,然后根据密度可有针对性的构架电源/地网络,大大提高了设计速度。另外,为降低占用了大量布线资源的电源/地网络对信号布线的不利影响,还对电源/地网络的布线宽度、间距和构架方式进行优化,提出了线宽、间距的计算公式,有效降低了设计的布线拥塞。最终实现了极低的电压降。

In the physical design of fiscal cash register SoC,a method based on routing density is introduced,first,determine metal layers＇ power routing density to satisfy the exactly estimated target IR drop,then P/G mesh can be quickly constructed according to the density.With the help of optimized design flow,turn-around time is decreased enormously.In order to avoid serious congestion induced by the high density P/G routing,several techniques are introduced to reduce via walls and optimize the P/G mesh＇s construction.Two formulas are proposed for computing the optimal P/G strap width and pitch.As a resuh,a SoC with low IR drop is achieved by a high density P/G mesh.