OCV, AOCV, POCV & Variation

Section goal

On-chip variation, derating, AOCV/POCV depth sensitivity, margin vs pessimism, and variation signoff dashboards.

How to study this section

1. Start with the topic hub to learn the contract.

2. Use mechanism and reports pages to connect rules to metrics.

3. Use debug and worked-example pages for interview and on-call practice.

4. Close with checklist and PPA impact before signing any change.

Topics

1. ocv-aocv-pocv-mechanisms/ — OCV / AOCV / POCV Mechanisms

2. derate-policy-and-approval/ — Derate Policy & Approval

3. path-depth-sensitivity/ — Path Depth Sensitivity

4. variation-signoff-dashboard/ — Variation Signoff Dashboard

Related topics

• STA course hub

STA deep dive

Variation policy is negotiated margin, not a tool checkbox.

Concept diagram

VARIATION STACK

nominal delay + OCV/AOCV/POCV margin = signoff delay

Metric graph

DERATE IMPACT ON WNS

OCV only     WNS -120ps
AOCV         WNS -45ps
POCV         WNS -60ps (policy dependent)

Reports and artifacts

• derate table

• AOCV depth report

• POCV sigma

• hold/setup split

Mini case study

Switched to AOCV without re-baselining hold — short paths failed min analysis.

Debug branches

• Short paths for hold

• Policy approval for derate changes

Senior review question

Ask: what corner/mode/view proves this topic is closed or failing?