As the designs migrate to advanced process nodes, the list of design rules for P&R tools gets longer and more complicated. Some of the rules, such as SI, DFM, and EM add rules, that used to be secondary to the designs, now become dominant. The traditional way of fixing those then-secondary-now-dominant rules during post-route stage may prove to be insufficient. At such a late stage, the designs no longer have the needed flexibility to make efficient and effective corrections. The consequences are compromised results and longer turn-around time.
Aprisa was created for advance technology nodes; hence, many nano-technology effects are accounted for early in the flow. Common analysis engines (sign-off-quality timer/SI/extraction/DRC) also help to maintain consistency and predictability throughout the flow. As a result, there are far fewer surprise violations during sign-off and dramatically reduces the ECO effort and overall turn-around time.
SI-aware placer and global route
Aprisa starts to factor in SI effects as early as in the place optimization and global routing, where the designs still have more flexibility to make effective and efficient changes to avoid potential difficult SI violations. The precision optimization ensures necessary routing details are available to make accurate SI estimation. Intelligent CCS data management minimizes the memory required for SI estimation throughout the flow. With the SI-aware placer and global route, most of the SI issues can be avoided or fixed before even getting to the detail route placement.
In-route DFM fixing
DFM fixing, such as wire-spreading, metal fill and DFM via insertion, are normally done, by most P&R tools, in the post-route stage. Aprisa incorporates those tasks during detail route, where the timing impact of the metal and vias can be property accounted for, and more flexibility can be given to maximize the metal density and DFM via rates. With the in-route DFM fixing, Aprisa is able to deliver better quality of DFM results.
Aprisa’s unique built-in EM analysis allows detection of potential signal-net EM violations and automatically fix them during routing. The highly efficient EM analysis engine also supports Etching effect for better accuracy. The EM fixing can be done with routing pattern changes that cause minimum impact to timing and area.