Verified calculation capability

ADC error budget Calculation Capability

Combine gain/offset/INL/DNL into LSB, volts, and %FS. · Electrical · Adc

Capability ID electrical.adc.error_budget · version 1.0.0

Open calculator REST API MCP Evidence Evidence JSON CVP Manifest Review policy

Model

LSB

LSB: LSB = FSR / 2^n
RSS: err = √(g²+o²+INL²+DNL²)
Worst case: err = |g|+|o|+|INL|+|DNL|

Inputs / Outputs

Canonical symbols for this capability. Agent schemas remain the contract.

Symbol	Quantity	Unit	Role
`n_bits`	Integer ADC resolution in bits.	—	input / output
`FSR`	Total analog input span in volts, not necessarily VREF. For a 0–3.3 V ADC, FSR_V = 3.3; for ±2.5 V, FSR_V = 5.	V	input / output
`gain_err_LSB`	Gain error already referred to LSB.	—	input
`offset_err_LSB`	Offset error already referred to LSB.	—	input
`inl_LSB`	Integral nonlinearity already referred to LSB.	—	input
`dnl_LSB`	Differential nonlinearity already referred to LSB. CalculatorX includes DNL as a separate RSS/worst-case contributor.	—	input
`combine`	rss treats contributors as independent/uncorrelated and is an engineering estimate, not a guaranteed bound. worst_case sums absolute LSB terms.	—	input / output
`LSB`	—	V	output
`err_LSB`	—	—	output
`err`	—	V	output
`err_pct_FS`	—	—	output

Assumptions / Validity

Declared scope for this capability. Do not use it outside this domain.

Assumptions

Gain, offset, INL, and DNL values are already referred to LSB.
RSS assumes contributors can be treated as independent/uncorrelated.
FSR_V represents the full ADC input span.
CalculatorX includes DNL as a separate RSS/worst-case contributor. Some ADC datasheets define TUE using gain, offset, and INL only.

Not supported

Dynamic ENOB from SINAD
jitter models

Example

One numerical check. The calculator page holds worked steps and FAQ.

12-bit 3.3V · RSS(1,0.5,1,0.5) → ≈1.58 LSB

Open this example in the calculator

Trust

CVP VERIFIED · CVP protocol 1.0.0-proposed · Engineering assurance · static DC LSB error-budget calculation. Computational verification is defined by CVP. Supplemental domain review (internal) and named expert review are defined by the Review policy and do not by themselves determine CVP conformance.

CVP: CVP VERIFIED · CVP protocol 1.0.0-proposed · Engineering assurance · static DC LSB error-budget calculation· View Manifest · CVP overview · Specification
Verified scope: static DC LSB error-budget calculation
Assurance: Engineering
Declared partition coverage: PASS · 6/6 declared partitions (rss, worst_case, zero-error, bit-width-bounds, single-term, invalid-domain)
Calculation version: 1.0.0
Verification: 11/11 calculation tests · 3/3 legacy golden · 6/6 legacy boundary · 2/2 legacy property
Production surface contract: 4/4
Versions: Calculation 1.0.0 · CVP protocol 1.0.0-proposed · Evidence 2026-09-09.o2-reproduce
Verification revision: 2026-09-09.o2-reproduce · 4/4 property · digest 39673b9b9f33
Reference: O1 model · O2 expected_values · O2 numerical_behavior
Numerical scope: Static DC LSB/V/%FS error-budget vs independent O2 (same V8, ≤2 ULP on err_LSB, LSB_V, err_V, err_pct_FS, codes). Not measured converter accuracy, not datasheet TUE that omits DNL, not O3.
Interfaces: PASS · UI (SSR) / REST / MCP
ui-ssr is query-result HTML, not a live browser session. Error-path engine·REST·MCP 4/4 (status, code, calculation_version). SSR compared on URL-canonical requested calculations; empty query is idle (not an error) and JSON-typed object/array inputs are REST/MCP-only. Probes use local Node handlers (query-result, calc API, MCP executeCalculation), not live production HTTP.
CVP suite: 6/6 golden · 6/6 CVP boundary · 5/5 invalid · 4/4 property · 6/6 metamorphic · 6/6 cross-interface · 1/1 CVP contract
Supplemental domain review: Internal · Pass · electrical-engineer
Named expert review: Not performed
Version lock: Supported (409 VERSION_MISMATCH)
Artifact consistency: Build verified · 1.0.0 (workspace artifacts agree)
Review-policy tier: Internal engineering review — catalog token expert_verified; supplemental; not CVP status

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

Call this capability

Human page, REST, and MCP share the same engine and calculation_version. Build verified hashes workspace artifacts only. After deploy, attest:production GETs canonical URLs twice — the public/cached view an Agent actually hits, and origin — including every /capabilities/{id} HTML page. Public Capability HTML version must match catalog before production attestation passes. Live Trust rows above fetch /.well-known/calculatorx-production-attestation.json and the output schema const. Build hashes: release integrity. That proves currently published page / engine / schema / evidence / MCP agree — not that a historical version is independently immutable. Reference Calculation Standard — Production surface contract 4/4.

Tool id: adc-error-budget
Engine: adc-error-budget
REST: POST /api/v1/calc/adc-error-budget
MCP: execute_calculation with capability_id: "electrical.adc.error_budget"
Agent input schema: Canonical (MCP / Agent)
Output schema: JSON Schema (latest)
Versioned input schema: Immutable pin (1.0.0)
Versioned output schema: Immutable pin (1.0.0)

References

Human-readable sources plus CVP reference evidence classes.

Sources

IEEE Std 1241 — ADC terminology — Gain, offset, INL, DNL
TI SLAA587 — ADC Performance Parameters — Total unadjusted error (TUE)
Analog Devices — The ABCs of Analog-to-Digital Converters — How ADC errors affect system performance

Reference evidence classes: O1 model · O2 expected_values · O2 numerical_behavior

Try with an agent

Inspect this capability via same-origin MCP, then call execute_calculation.

curl -sS -X POST 'https://www.calculatorx.com/mcp' \
  -H 'Content-Type: application/json' \
  -H 'MCP-Protocol-Version: 2026-07-28' \
  -H 'Mcp-Method: tools/call' \
  -H 'Mcp-Name: inspect_capability' \
  -d '{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"inspect_capability","arguments":{"capability_id":"electrical.adc.error_budget"}}}'

Inspect the trust tier and required assurance level before execution. Pin calculation_version (1.0.0) when reproducibility matters. Full protocol notes: MCP docs.