No two gates on a die are identical, and timing analysis must account for that without being so cautious that nothing closes. This section builds the three standard methods from arithmetic, treats derates and margins as a managed policy, shows how path depth changes everything, and ends with the numbers that matter during closure. Each lesson has a runnable example.
Lesson | After it you can... |
|---|---|
Apply late and early derates with CRPR. | |
Explain depth credit. | |
Combine sigmas along a path. | |
Compare three methods. | |
Derive a derate from data. | |
Keep a margin ledger. | |
Measure the cost of excess. | |
Audit applied derates. | |
Simulate the averaging. | |
Compare hold and setup cost. | |
Quantify clock skew uncertainty. | |
See three methods on twenty paths. | |
Choose dashboard metrics. | |
Normalise for margin edits. | |
Compare common endpoints. | |
Check package completeness. |
Suggested order: top to bottom. Previous sections: Multi-Corner Multi-Mode Signoff, Advanced Checks and Delay Graph and Path Analysis.
The statistical method; flat needs only two factors and depth-based needs tables indexed by stage count and often distance.