Design space exploration

For ADC Digital Wrapper, closure options trade robustness, schedule, and margin.

Option A — conservative

• Conservative boundary guard: helps high robustness

• Risk: area and schedule cost

• Validate with: first-silicon risk

Option B — balanced

• Balanced integration policy: helps practical closure

• Risk: needs discipline

• Validate with: production ramp

Option C — aggressive

• Aggressive late ECO: helps quick symptom relief

• Risk: cross-domain regressions

• Validate with: deadline crunch

Option D — structural

• Architecture-level reshaping: helps durable fix

• Risk: long lead time

• Validate with: repeat offenders

DESIGN SPACE — ADC Digital Wrapper
robustness <-> performance <-> schedule
choose by sample capture integrity, wrapper protocol violations, dropped-frame count on product-representative scenarios

Design pitfalls

• Mode coverage too shallow

• Fixing symptom without ownership alignment

Tradeoff curve

BEFORE / AFTER — ADC Digital Wrapper

health score
  ^
  |                     --- target
  |         o regressed
  |               o before fix
  |                    o after bounded fix
  +--------------------------------------> debug iteration

Prove signal quality, timing margin, and integration safety together.

AMS deep dive

Wrapper and sampling contracts determine data trustworthiness.

Concept diagram

CONVERTER DATA FLOW

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

Metric graph

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

ADC wrappers bridge analog sampler behavior to synchronous digital domains with framing, synchronization, and error flags that preserve measurement validity.

Metric: sample capture integrity, wrapper protocol violations, dropped-frame count