From RTL to GDS: Why Timing Correlation Makes or Breaks Your Tapeout

When “Clean Timing” Isn’t Really Clean

Your synthesis run looks perfect—no major violations, healthy slack. But weeks later, signoff won’t converge. If this sounds familiar, you’ve hit the hidden cost of poor timing correlation.

Timing correlation isn’t just a signoff issue—it spans the entire RTL-to-GDS flow. When it breaks, teams waste cycles debating mismatches, ECO loops grow, and QoR suffers.

Want to fix it? Join our Cadence TECHTALK to learn proven strategies to close the gap early.

CadenceTECHTALK: Faster Turnaround, Better QoR - Timing Correlation Recipes Across RTL to GDS

Where Correlation Breaks

• RTL and synthesis: Missing physical effects, inconsistent models
• Pre- to post-route: RC, SI, and metal fill differences
• Constraints and analysis: SDC mismatches, derates, GBA vs. PBA gaps

How Cadence Helps You Fix It

Correlation improves when physical reality is introduced earlier in the flow:

• Joules: Early PPAC visibility at RTL
• Genus + Innovus: Better pre-route timing prediction

Key techniques covered in the webinar:

• Early Clock Flow (ECF) and Detailed Routing
• Integrated Virtual Metal Fill (IVMF)
• Early PBA (ePBA)
• Integrated Signoff Closure (ISC)

What You’ll Learn in This TECHTALK

In this session, you’ll discover:

• Proven methods to debug mismatches step by step
• Techniques to improve pre-route to signoff alignment
• How AI-driven optimization reduces over-constraint

References

• Innovus to Tempus Timing Correlation

https://support.cadence.com/apex/ArticleAttachmentPortal?id=a1Od00000066PvSEAU

• Ostrich RC Correlation

https://support.cadence.com/apex/ArticleAttachmentPortal?id=a1Od000000050M9EAI

• Timing Correlation using TimeEx 3.0

https://support.cadence.com/apex/ArticleAttachmentPortal?id=a1Od000000050WcEAI

• Integrated Virtual Metal Fill RAK (IVMF)

https://support.cadence.com/apex/articleattachmentportal?id=a1O3w000009kuIgEAI

• Statistical On-Chip Variation (SOCV) with Spatial Timing Derates in Tempus

https://support.cadence.com/apex/ArticleAttachmentPortal?id=a1O0V000009EWOcUAO

• Stylus Compare 23.1 (CUI) RAK

https://support.cadence.com/apex/ArticleAttachmentPortal?id=a1O0V0000091CiDUAU