Low Power Verification · All levels

Corruption and Retention Simulation: Mechanism

Mechanism for Corruption and Retention Simulation.

Mechanism to understand

Mechanism for Corruption and Retention Simulation is anchored on illegal transition rate, corruption incidence, and deterministic replay quality under low-power scenarios. Convert observations into mechanism-backed and owner-bound actions.

Validate signal corruption semantics on power-down by proving non-retained state collapses to unknown or tool-defined corrupt values at the expected boundary and time, instead of silently preserving stale logic values. In parallel, verify retention strategy behavior: save and restore handshakes, retention supply availability, and retained element correctness across repeated cycling and corner ordering. Effective tests combine directed stress and assertion-based checks to catch false confidence cases where simulations pass because stimulus avoids the vulnerable transition window rather than because corruption and restore behavior are implemented correctly.

  • Name first boundary where expected transition behavior diverges.

  • Prove mechanism with one high-confidence evidence packet.

  • Assign owner for smallest reversible mitigation.

Execution flow

diagram
LOW-POWER VERIFICATION FLOW - Corruption and Retention Simulation

power intent and mode definitions
      |
      v
domain controls and transition sequencing
      |
      v
simulation behavior (isolation, retention, corruption)
      |
      v
assertions and coverage evidence
      |
      v
triage, bounded fix, and signoff closure

Low-power verification deep dive

Power-aware simulation quality is measured by realistic transition behavior and actionable failure classification.

Concept diagram

diagram
POWER-AWARE SIM FLOW

UPF + RTL + testbench -> elaboration -> transition simulation -> assertions and triage

Metric graph

diagram
SIM QUALITY SIGNALS

false-fail noise      █████
actionable failures   ███████
deterministic replay  ████████

Metrics and artifacts to collect

  • elaboration semantic report

  • power-aware run reproducibility matrix

  • corruption and clamp behavior summary

  • assertion signal-to-noise trend

Mini case study

A noisy regression became actionable after bucketing failures by transition phase and boundary type before fixing checks.

Debug branches

  • Start from first failing phase, not final mismatch.

  • Check semantic setup consistency before declaring design bug.

  • Use one reproducible scenario per hypothesis branch.

Senior review question

Ask: what exact low-power transition boundary failed first, and which artifact proves the closure claim reproducibly?

Key takeaways

  • Tie each LPV claim to a concrete transition boundary and one proving artifact.

  • Prefer minimal reversible fixes with explicit owner and rollback criteria.

Common pitfalls

  • Treating power-aware failures as random before boundary classification.

  • Waiving X-prop failures before proving impact and root cause.

  • Declaring closure without deterministic replay across key modes.

Mechanism deep dive

Mechanism detail: Validate signal corruption semantics on power-down by proving non-retained state collapses to unknown or tool-defined corrupt values at the expected boundary and time, instead of silently preserving stale logic values. In parallel, verify retention strategy behavior: save and restore handshakes, retention supply availability, and retained element correctness across repeated cycling and corner ordering. Effective tests combine directed stress and assertion-based checks to catch false confidence cases where simulations pass because stimulus avoids the vulnerable transition window rather than because corruption and restore behavior are implemented correctly.

Strong explanations tie transition semantics directly to observed failures.