BeginnerQuestion 25 of 40Source PDF page 24

What is a hold violation, and what does it mean physically?

From PDVerse STA Mentor Guide · pdVerse Mentor Guide

Short Answer

Slack, in general, is required minus arrival, and a violation of any kind (setup or hold) simply means that slack has gone negative for that check.

Example

The report_timing anatomy shows the 'MET'/'VIOLATED' labeling convention directly: 'MET' means the path's slack is at least 0, and 'VIOLATED' means slack is less than 0.

Why It Matters

A negative slack on a timing check tells you the timing requirement encoded in the SDC and library was not satisfied for that path, and the notes stress that these failures are usually silent omissions in constraints rather than dramatic, obviously visible failures, so you have to actually look for them in reports.

Equation

Slack = required - arrival

Mentor Note — Common Mistake

Don't assume a clean-looking report has no violations hiding in it. Signoff failures are often silent gaps in what was even checked, not loud red flags, so always confirm the design was fully and correctly constrained first.

Visual explanationSTA context: What is a hold violation, and what does it mean physically?
STA context: What is a hold violation, and what does it mean physically?A three-step concept map summarizes the focus, core answer, and practical verification for What is a hold violation, and what does it mean physically?Question focusWhat is a holdviolation, and what doesit mean physically?Core answerSlack, in general, isrequired minus arrival,and a violation of any…Verify in practiceConfirm the path,constraints, clockassumptions, and timingreport.Understand → explain the mechanism → verify the assumptions

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