Public evidence

electrical.mosfet.conduction_loss

Machine-checked verification for calculation version 1.2.2 · tier internally_reviewed

Open calculator API Capability Download JSON CVP Manifest MCP Review policy

CVP: CVP VERIFIED · CVP protocol 1.0.0-proposed · Engineering assurance· Conduction only — switching/Coss/Qrr excluded; temperature none in this CVP wave goldens · Protocol · Schema · Production report

Declared partition coverage: PASS · 4/4 declared partitions (dc, on_interval_rms, full_cycle_rms, invalid-domain)
Versions: Calculation 1.2.2 · CVP protocol 1.0.0-proposed
CVP identity: 8/8 property · digest 77fa2f728b57

Verification

Legacy regression suite: 32/32 calculation tests · Production surface contract 12/12

Three distinct suites: educational examples on the calculator page, this legacy regression count (32/32 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 1.2.2 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 1.2.2. CVP 1.0.0-proposed. 3/3 golden · 13/13 CVP boundary · 13/13 invalid · 8/8 property · 2/2 cross-interface · 12/12 CVP contract. digest 77fa2f728b57.

Golden (oracle-backed) 3 / 3
CVP boundary 13 / 13
Invalid input 13 / 13
Property 8 / 8
Cross-interface 2 / 2
CVP contract 12 / 12
Interfaces PASS · UI (SSR) / REST / MCP
Interface claim ui-ssr is query-result HTML, not a live browser session.
Assurance Engineering

contract page version PASS
contract capability version PASS
contract input schema version PASS
contract output schema version PASS
evidence version matches manifest PASS
schema valid input executes PASS
engine success output validates schema PASS
schema rejects incomplete input PASS
temperature linear schema requires Tj_C PASS
temperature ratio schema requires rds_ratio PASS
temperature inference precedence PASS
share url roundtrip ohm milliohm PASS

Fingerprint sha256:68d50719e16748809e011bfb008707e18aed847d9d57991041da0ac508ed90d8

Input schema sha256:20a3903576755b30cf90912ba3998e62c6529eeec8bd978f32390c50c5db13e7 · Output schema sha256:2f495e23acd9d7e343c9d6a1012542973b61e700ab54442d17409528dab9d7ac · 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: mosfet-conduction-loss
Engine: mosfet-conduction-loss
Engine build: 2026-09-10
Evidence core: 2026-09-05T02:35:39.217Z
Rendered: 2026-09-16T22:03:43.713Z
Last reviewed: 2026-08-14

Assumptions

Constant Rds during on-time at the applied Rds_Tj.
current_basis is the contract for what I means; the engine will not guess a waveform factor.
No switching, Coss, or gate-drive loss.
Rds(Tj) is first-order linear or a datasheet ratio — not a physics compact model.
Default α = 0.006 /°C is a Si MOSFET planning default, not manufacturer validated.

Limitations

Conduction loss only — not switching, reverse recovery, or gate drive
Rds(Tj) is optional first-order linear or datasheet-ratio — not a physics compact model
Default α = 0.006 /°C is a Si MOSFET planning default, not manufacturer validated
current_basis selects the I definition; mixing full-cycle RMS with D double-counts duty
V_drop is I·Rds_Tj at the entered current, not a measured VDS(on) waveform point
Missing/non-positive I/Rds → MISSING_REQUIRED_INPUT / VALUE_MUST_BE_POSITIVE; D outside (0,1] → FRACTION_OUT_OF_RANGE; unknown current_basis or temperature_model → INVALID_MODE

Sources

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

IEC 60747-8 — Semiconductor devices — Discrete devices — Part 8: Field-effect transistors — Drain-source on-state resistance RDS(on)
Supports: RDS(on) as the on-state resistance used in conduction-loss estimates
Infineon — OptiMOS device selection for synchronous rectification — Conduction losses P_cond = I_RMS² × RDS(on)
Supports: Vendor conduction-loss model using MOSFET RMS current (not converter output current) without an extra duty factor
Texas Instruments SSZTB57 — How to Minimize MOSFET Conduction Loss in Battery-Powered Applications — P_cond = I_RMS² × RDS(on)
Supports: Official TI conduction-loss formula using MOSFET RMS current
Erickson & Maksimović — Fundamentals of Power Electronics — Conduction loss in semiconductor switches
Supports: I_rms of the switch current over the period; equivalent to on-interval RMS × √D for rectangular current
NIST Guide to the SI (SP 811) — SI units for current, resistance, and power
Supports: A, Ω, W relationships

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
`dc-10a-50mohm`	golden	pass	Expected P_W=5 · V_drop=0.5 · D=1 · current_basis=dc · Actual P_W=5 · V_drop=0.5 · I=10 · Rds=0.05 · Rds_Tj=0.05 · D=1 · current_basis=dc · temperature_model=none
`on-interval-pwm-half`	golden	pass	Expected P_W=2.5 · V_drop=0.5 · D=0.5 · current_basis=on_interval_rms · Actual P_W=2.5 · V_drop=0.5 · I=10 · Rds=0.05 · Rds_Tj=0.05 · D=0.5 · current_basis=on_interval_rms · temperature_model=none
`full-cycle-rms-equiv`	golden	pass	Expected P_W=2.5 · current_basis=full_cycle_rms · D=1 · Actual P_W=2.5000000000000004 · V_drop=0.3535533905932738 · I=7.0710678118654755 · Rds=0.05 · Rds_Tj=0.05 · D=1 · current_basis=full_cycle_rms · temperature_model=none
`full-cycle-no-double-duty`	golden	pass	Expected P_W=2.5 · D=1 · Actual P_W=2.5000000000000004 · V_drop=0.3535533905932738 · I=7.0710678118654755 · Rds=0.05 · Rds_Tj=0.05 · D=1 · current_basis=full_cycle_rms · temperature_model=none
`low-rds-20a`	golden	pass	Expected P_W=2 · V_drop=0.1 · Actual P_W=2 · V_drop=0.1 · I=20 · Rds=0.005 · Rds_Tj=0.005 · D=1 · current_basis=dc · temperature_model=none
`legacy-omitted-basis`	boundary	pass	Expected MISSING_REQUIRED_INPUT · Actual MISSING_REQUIRED_INPUT
`xref-infineon-irms-rds`	formula cross-check	pass	Expected P_W=2 · Actual P_W=2 · V_drop=0.2 · I=10 · Rds=0.02 · Rds_Tj=0.02 · D=1 · current_basis=full_cycle_rms · temperature_model=none
`xref-ti-irms-rds`	formula cross-check	pass	Expected P_W=1 · Actual P_W=1 · V_drop=0.2 · I=5 · Rds=0.04 · Rds_Tj=0.04 · D=1 · current_basis=full_cycle_rms · temperature_model=none
`xref-erickson-on-interval`	formula cross-check	pass	Expected P_W=0.64 · Actual P_W=0.6400000000000001 · V_drop=0.2 · I=8 · Rds=0.025 · Rds_Tj=0.025 · D=0.4 · current_basis=on_interval_rms · temperature_model=none
`tj-ratio-1.44`	golden	pass	Expected P_W=7.2 · P_W_ref=5 · V_drop=0.72 · Rds_Tj=0.072 · temperature_model=ratio · Actual P_W=7.199999999999999 · V_drop=0.72 · I=10 · Rds=0.05 · Rds_Tj=0.072 · D=1 · current_basis=dc · temperature_model=ratio
`tj-linear-alpha`	golden	pass	Expected P_W=7.25 · P_W_ref=5 · Rds_Tj=0.0725 · temperature_model=linear · Actual P_W=7.249999999999999 · V_drop=0.725 · I=10 · Rds=0.05 · Rds_Tj=0.0725 · D=1 · current_basis=dc · temperature_model=linear
`xref-infineon-hot-rds`	formula cross-check	pass	Expected P_W=7.2 · Rds_Tj=0.072 · Actual P_W=7.199999999999999 · V_drop=0.72 · I=10 · Rds=0.05 · Rds_Tj=0.072 · D=1 · current_basis=dc · temperature_model=ratio
`boundary-missing-I`	boundary	pass	Expected MISSING_REQUIRED_INPUT · Actual MISSING_REQUIRED_INPUT
`boundary-missing-Rds`	boundary	pass	Expected MISSING_REQUIRED_INPUT · Actual MISSING_REQUIRED_INPUT
`boundary-zero-I`	boundary	pass	Expected VALUE_MUST_BE_POSITIVE · Actual VALUE_MUST_BE_POSITIVE
`boundary-zero-Rds`	boundary	pass	Expected VALUE_MUST_BE_POSITIVE · Actual VALUE_MUST_BE_POSITIVE
`boundary-zero-duty`	boundary	pass	Expected FRACTION_OUT_OF_RANGE · Actual FRACTION_OUT_OF_RANGE
`boundary-bad-duty`	boundary	pass	Expected FRACTION_OUT_OF_RANGE · Actual FRACTION_OUT_OF_RANGE
`boundary-nan-Rds`	boundary	pass	Expected INVALID_NUMBER · Actual INVALID_NUMBER
`boundary-invalid-basis`	boundary	pass	Expected INVALID_MODE · Actual INVALID_MODE
`boundary-invalid-temp-model`	boundary	pass	Expected INVALID_MODE · Actual INVALID_MODE
`boundary-zero-rds-ratio`	boundary	pass	Expected VALUE_MUST_BE_POSITIVE · Actual VALUE_MUST_BE_POSITIVE
`boundary-linear-needs-tj`	boundary	pass	Expected MISSING_REQUIRED_INPUT · Actual MISSING_REQUIRED_INPUT
`boundary-linear-factor-nonpositive`	boundary	pass	Expected VALUE_MUST_BE_POSITIVE · Actual VALUE_MUST_BE_POSITIVE
`property-vdrop`	property	pass	V_drop=I·Rds at entered current
`property-i2`	property	pass	2I → 4P
`property-rds`	property	pass	2Rds → 2P
`property-duty-on-interval`	property	pass	on-interval D=0.5 → ½P vs DC
`property-full-cycle-ignores-duty`	property	pass	full-cycle RMS does not multiply by D
`property-rms-equivalence`	property	pass	I_on=10 A, D=0.5 equals I_rms=10√0.5
`property-ratio-scales-p`	property	pass	rds_ratio=1.44 → P_Tj = 1.44 · P_ref
`property-linear-at-tref`	property	pass	linear Tj=Tref → identity