AMS Interface · All levels

Calibration Hooks: Inputs & Outputs

Inputs & Outputs for Calibration Hooks.

Inputs and outputs contract

Inputs & Outputs for Calibration Hooks focuses on calibration convergence time, calibration residual error, re-trim rate. The goal is to connect observed symptom to boundary mechanism, ownership, and signoff risk.

Treat these inputs and outputs as signed interface guarantees. Ambiguity here creates the most expensive integration bugs.

diagram
INPUTS
  - AMS handoff contract and spec revision
  - mode definitions (power/clock/reset/traffic)
  - wrapper and boundary-cell assumptions
  - physical constraints: keepouts, guard, package limits

OUTPUTS
  - mode-tagged metric report
  - owner-signed debug or closure note
  - waiver manifest with expiry and controls
  - release recommendation

Boundary sequence

diagram
AMS BOUNDARY SEQUENCE — Calibration Hooks

analog macro -> wrapper / boundary cell -> synchronizer or sampler -> digital consumer
      |                 |                         |                     |
  analog assumptions    legal voltage/state       clock/reset contract   protocol/data validity

metric under watch: calibration convergence time, calibration residual error, re-trim rate

Ownership map

diagram
OWNERSHIP MAP — Calibration Hooks

artifact                  owner
----------------------    -----------------------------
integration artifact    firmware owner
implementation artifact analog designer
signoff artifact        test engineer

Every boundary issue needs a named owner before fixes start.

AMS deep dive

Wrapper and sampling contracts determine data trustworthiness.

Concept diagram

diagram
CONVERTER DATA FLOW

sampling clock -> wrapper -> sync boundary -> system consumer

Metric graph

diagram
INVALID SAMPLE BURSTS

time --->  _|¯¯|__|¯¯¯|____|¯|_

Reports and artifacts

  • sample validity ratio

  • calibration convergence

  • CDC audit

  • overflow/stale sample counters

Mini case study

Mode transition changed sample phase and invalidated wrapper framing assumptions.

Debug branches

  • Sample timing contract

  • Calibration hook behavior

  • Wrapper CDC integrity

Senior review question

Ask: what boundary condition proves this topic is actually closed?

Key takeaways

  • State boundary, mode, and evidence tag with every claim.

  • Always align analog, digital, and physical owners before signoff decisions.

Common pitfalls

  • Fixing averages while tails still fail.

  • Skipping package/supply evidence in jitter or SerDes issues.

  • Shipping with waivers that lack owner and expiration criteria.

Principal AMS review addendum

Digital hooks expose trims and adaptation points that correct analog mismatches; poor hook design leaves no observability when field drift appears.

Metric: calibration convergence time, calibration residual error, re-trim rate