If a design has both IR drops and congestion, there are a few potential solutions to fix the issue,
- Spread macros.
- Power grid redesign
- Use proper blockage.
- Using buffering cells
- Spread standard cells.
- Increase strap width.
- Increase the number of straps.
- Optimizing the placement of the cells
When a design encounters both IR drops and congestion, addressing these issues effectively requires a combination of strategies. Let’s explore what you can do to resolve them.
Spread macros.
First, spreading macros can help. By ensuring that macros are evenly distributed, you minimize hotspots in the design that could lead to congestion and localized IR drops. Similarly, spreading standard cells ensures a balanced placement, which reduces routing congestion and improves power distribution.
Power grid redesign
Next, consider a power grid redesign. You can strengthen the power grid to reduce resistance and improve voltage delivery across the design. Additionally, increasing the strap width or adding more straps are effective ways to enhance current-carrying capacity, thereby mitigating IR drops. These adjustments distribute power more evenly, ensuring all parts of the design receive sufficient voltage.
Use Proper blockage
Proper use of blockages is another essential step. By defining blockages appropriately, you can control routing and cell placement to avoid congestion in critical areas. Buffering cells can also play a key role in managing signal integrity and timing, especially in congested regions where delays might occur.
Optimizing the placement of the cells
Finally, optimizing the placement of cells can provide significant improvements. By strategically placing cells, you not only address routing congestion but also ensure better power delivery paths.
At every step, collaboration is key. As we implement these changes, reviewing the design’s progress ensures that the fixes work cohesively. It’s a process of trial and refinement, but with these strategies, we can reduce IR drops and congestion, delivering a robust design. Together, we can achieve an efficient and reliable solution.
