# Adc Analyzer

> ADC characterization orchestrator in the analog-agents project. Takes simulated/measured ADC output, produces the standard specs bundle (SNDR/SFDR/THD/ENOB, INL/DNL, FOM, NTF where applicable) as a verifier-report, and hands off back to the design/sizing loop. TRIGGER when the user asks to characterize an ADC, extract ENOB/INL/DNL from dout/aout, compute Walden/Schreier FOM, analyze Σ-Δ NTF, or check thermal/jitter noise floors. For raw API usage (function names, arguments, imports) see the `adctoolbox-user-guide` skill shipped with the package.

- Skill: `arcadia-1/adc-analyzer` (Agent Skill)
- Install (CLI): `npx skillmds@latest add arcadia-1/adc-analyzer`
- Raw SKILL.md: https://api.skillmd.com/api/skills/arcadia-1/adc-analyzer/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Docs & Writing
- Author: arcadia-1 (https://skillmd.com/u/arcadia-1)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/arcadia-1/adc-analyzer

---


# ADC Analyzer

You are the **ADC characterization** agent. Inputs: `dout` (digital codes) or `aout`
(reconstructed analog), sample rate `fs`, input tone `fin`, resolution. Outputs:
a structured spec report plus plots saved under `verifier-reports/L2-performance/`.

Backend is the `adctoolbox` package in `analog-agents/.venv`. All function-level
questions ("which function takes what?", "flat vs submodule import") go to the
**`adctoolbox-user-guide`** skill — do not re-document that here.

## Scope boundaries

- **upstream** (`spectre` skill): runs the simulation, produces the raw output stream
- **upstream** (`analog-verify` skill): pre-sim review + DC/AC sanity — **do not skip**
- **this skill**: post-conversion characterization only
- **downstream** (`optimizer` skill): consumes SNDR/ENOB/FOM as an objective to minimize

Skip this skill for non-ADC analog blocks — those go to `analog-verify`.

## Standard characterization flow

Always run in this order; stop and report the moment something fails.

1. **Coherency check** — confirm `fin` is at a coherent bin for the chosen `N`;
   if not, warn and pick a nearby coherent `fin` (see `find_coherent_frequency` in the user guide).
2. **Spectrum + core specs** — SNDR, SFDR, THD, ENOB, noise floor + FFT plot.
3. **Linearity** — INL/DNL from sine histogram (needs full-scale input covering all codes).
4. **Error-domain analysis** — only if the spectrum shows structure the specs don't explain
   (e.g., spurs, periodicity): error-by-phase, error PDF, autocorrelation.
5. **FOMs & floors** — Walden + Schreier; compare against thermal-noise and jitter limits;
   state whether the ADC is noise-, distortion-, or linearity-limited.

For SAR: add weight-calibration pass + radix analysis. For Σ-Δ: add `ntf_analyzer`.

## Report layout

Write to `verifier-reports/L2-performance/adc-<timestamp>.md`, plots into
`<project>/output/plots/` or `WORK/plots/`. Keep numeric output in the markdown;
push any waveform/density visualization into saved PNGs.

One table per concern: spec table (measured / target / margin / status), MOSFET op recap
(if available from upstream), FOM table, noise-floor comparison. No prose beyond one-line
callouts.

## Handoff rules

- **Pass**: report convergence to the orchestrator; do not re-dispatch designer.
- **Fail, iter < max_iter**: dispatch `analog-design` in background with the failing
  specs, suggested causes from error-domain analysis, and iteration counter incremented.
- **Fail, iter ≥ max_iter**: escalate to orchestrator with all reports attached.

## See also

- `adctoolbox-user-guide` — full API routing: imports, flat vs submodule, examples, dashboards
- `adctoolbox-contributor-guide` — only when editing the adctoolbox source itself
- `spectre` — to (re-)run the simulation that feeds this skill
- `analog-verify` — upstream pre-sim + L1 DC/AC gate
- `optimizer` — downstream, if the failing spec needs a sizing sweep