Public evidence

electrical.pcb.microstrip

Machine-checked verification for calculation version 1.0.0 · tier expert_verified

Open calculator API Capability Download JSON CVP Manifest MCP Review policy

CVP: CVP VERIFIED · CVP protocol 1.0.0-proposed · Engineering assurance· No copper thickness correction; er>1 · Protocol · Schema · Production report

Declared partition coverage: PASS · 3/3 declared partitions (z0, width, invalid-domain)
Versions: Calculation 1.0.0 · CVP protocol 1.0.0-proposed
CVP identity: 3/3 property · digest dead067b2144

Verification

Legacy regression suite: 8/8 calculation tests · Production surface contract 4/4

Three distinct suites: educational examples on the calculator page, this legacy regression count (8/8 golden + boundary), and the CVP verification suite below. They are not the same number. Property, metamorphic, round-trip, O3, and interface statuses/checks are recorded in the CVP Manifest . SKIP (0/0) means that suite has no published vectors.

This calculator CURRENT · Public schema 1.0.0 matches · Semantic contract ✓ · Production attested · Public/cache ✓ · Origin ✓

CVP verification suite

Protocol checks from the Evidence Manifest. Distinct from the legacy regression suite above. Calculation version 1.0.0. CVP 1.0.0-proposed. 2/2 golden · 3/3 CVP boundary · 2/2 invalid · 3/3 property · 1/1 cross-interface · 1/1 CVP contract. digest dead067b2144.

Golden (oracle-backed) 2 / 2
CVP boundary 3 / 3
Invalid input 2 / 2
Property 3 / 3
Cross-interface 1 / 1
CVP contract 1 / 1
Interfaces PASS · UI (SSR) / REST / MCP
Interface claim ui-ssr is query-result HTML, not a live browser session.
Assurance Engineering

release artifacts aligned PASS
schema valid input executes PASS
engine success output validates schema PASS
schema rejects incomplete input PASS

Fingerprint sha256:17d969cca89f627b7e7045ca5e742220fdea626593ca0b1836ad564b53c537d9

Input schema sha256:c8f5e89b40a159bb8ae10cc9546adf06871634916d84967655d046ed1c738017 · Output schema sha256:adc7277017778b89ecd94bee3383302bc7bf9f2922053350d668009ed176b57a · Build-time SHA-256 digests prove published artifacts agree with each other (release_integrity.scope=workspace). Production attestation GETs canonical URLs twice (public/cached view and origin), including Capability HTML, via npm run attest:production --write (published at /.well-known/calculatorx-production-attestation.json) and fails if the public Capability page advertises a different calculation_version. This is artifact consistency, not an independent immutable release log.

Build & scope

Engine identity and declared limitations.

Tool: pcb-microstrip
Engine: pcb-microstrip
Engine build: 2026-09-10
Evidence core: 2026-09-05T02:35:39.217Z
Rendered: 2026-09-16T22:03:43.719Z
Last reviewed: 2026-08-08

Limitations

Zero thickness; no soldermask
er≤1 → ER_MUST_BE_GT_1

Sources

Standards and references supporting this tool specification. Methods are listed separately — they are algorithms, not bibliographic sources.

IPC-2141A — Controlled Impedance Circuit Boards and High-Speed Logic Design — Microstrip impedance equations
Supports: Closed-form Z0 vs W/H/εr
Hammerstad / Jensen / Wadell microstrip models — Effective permittivity and Z0
Supports: εeff and narrow/wide branch formulas

Legacy published checks

Golden and boundary cases from the legacy Evidence JSON. CVP property, metamorphic, round-trip, O3, and interface statuses/checks are recorded in the Manifest — including SKIP when a suite has no vectors.

ID	Kind	Status	Detail
`z0-wide`	golden	pass	Expected Z0_ohm=50.204986595296894 · eps_eff=3.4578600028832134 · Actual mode=z0 · W_m=0.00037 · H_m=0.0002 · W_mm=0.37 · H_mm=0.2 · er=4.6 · Z0_ohm=50.204986595296894 · eps_eff=3.4578600028832134
`width-50`	golden	pass	Expected W_m=0.0003698174943687439 · Actual mode=width · W_m=0.0003698174943687439 · H_m=0.0002 · W_mm=0.3698174943687439 · H_mm=0.2 · er=4.6 · Z0_ohm=50 · eps_eff=3.4577194031386447
`er-bad`	boundary	pass	Expected ER_MUST_BE_GT_1 · Actual ER_MUST_BE_GT_1
`missing-W`	boundary	pass	Expected MISSING_REQUIRED_INPUT · Actual MISSING_REQUIRED_INPUT
`boundary-z0`	boundary	pass	Expected Z0_ohm=50.204986595296894 · Actual mode=z0 · W_m=0.00037 · H_m=0.0002 · W_mm=0.37 · H_mm=0.2 · er=4.6 · Z0_ohm=50.204986595296894 · eps_eff=3.4578600028832134
`property-z0`	property	pass	~50Ω FR4
`property-width`	property	pass	width>0
`property-wider`	property	pass	wider → lower Z0