SMAJ20A

20V-standoff TVS diode, VBUS_IN surge/overvoltage clamp — High Diode — C571370 — board-a D5 (fitted) — rec-high-diode-smaj20a-c571370

Generated from the component evidence records — edit the records, not this page.

Everything below is projected from this project's stored component evidence. Values keep the exact wording, conditions, units and verdicts they were recorded with — nothing here is re-typed, corrected, or combined into an overall judgement about the part.

This record in the catalog: SMAJ20A

Identity

Field	Recorded value
Record ID	`rec-high-diode-smaj20a-c571370`
Record kind	standalone
Manufacturer part number	`SMAJ20A`
Manufacturer	High Diode
Function	20V-standoff TVS diode, VBUS_IN surge/overvoltage clamp
LCSC ID	`C571370`
Package	`D-FLAT_L4.3-W2.6-LS5.3-RD`
Inventory line	`line-c571370`
Also known as	`20 V TVS diode`, `VBUS_IN TVS`

Fit: Fitted

Identity state: VERIFIED

Source state: AVAILABLE

Coverage: 1 open of 7 published

Documents and package

Datasheet PDF

High Diode SMAJ series transient voltage suppressors

Authority: MANUFACTURER_PRIMARY
Availability: AVAILABLE

Footprint preview

Package model

Shared footprint package: D-FLAT_L4.3-W2.6-LS5.3-RD. Open model file

Interactive inspection requires JavaScript and WebGL. The package identity remains available in this page.

This geometry represents a shared footprint package and may not exactly match the manufacturer part.

Datasheet PDF — High Diode SMAJ series transient voltage suppressors

Selected source ID: src-smaj20a-c571370-primary

Authority: MANUFACTURER_PRIMARY

Availability: AVAILABLE

Package footprint: D-FLAT_L4.3-W2.6-LS5.3-RD

This geometry represents a shared footprint package and may not exactly match the manufacturer part.

Placements

Every position this exact line occupies in the as-built design. One line may be placed many times and across more than one board.

Board	Reference designator
board-a	`D5`

Coverage

Coverage is stated one domain at a time and is never rolled up. A domain marked open is a question that has not been answered; it is not a finding that the part is unsuitable. A record with no open domains has not thereby been declared safe.

manufacturer-and-MPN identity

Coverage ID: cov-high-identity · Status: COVERED

Reason: Official High Diode PDF contains the exact SMAJ20A row.

Facts in this domain:

fact-high-diode-smaj20a-manufacturer

exact C571370 distributor binding

Coverage ID: cov-high-orderable · Status: COVERED

Reason: Available stable distributor evidence confirms only the C571370-to-High-Diode-SMAJ20A orderable identity binding.

Facts in this domain:

fact-high-diode-smaj20a-identity

standoff/breakdown/clamp/leakage ratings

Coverage ID: cov-high-ratings · Status: COVERED

Reason: Official exact SMAJ20A row supplies conditioned VRWM, VBR, IR, IPP and VC limits.

Facts in this domain:

fact-high-diode-smaj20a-standoff
fact-high-diode-smaj20a-breakdown
fact-high-diode-smaj20a-clamp
fact-high-diode-smaj20a-leakage

pulse waveform/derating and thermal limits

Coverage ID: cov-high-pulse · Status: COVERED

Reason: Official PDF supplies atomic PPPM and temperature facts plus 10/1000 us waveform and derating context.

Facts in this domain:

fact-high-diode-smaj20a-thermal
fact-high-diode-smaj20a-temperature

polarity marking

Coverage ID: cov-high-polarity · Status: COVERED

Reason: Official PDF states that the device band marks cathode.

Facts in this domain:

fact-high-diode-smaj20a-polarity

board-a D5 net mapping

Coverage ID: cov-smaj20a-project-nets · Status: COVERED

Reason: board-a-baseline confirms D5.1 (cathode) on VBUS_IN and D5.2 (anode) on GND, consistent with the datasheet's band-marks-cathode polarity fact; this is the post-#93-fix topology that replaced the removed D4 (USBLC6-2SC6).

Facts in this domain:

fact-high-diode-smaj20a-polarity
fact-smaj20a-d5-nets

as-built D5 orientation/continuity confirmation

Coverage ID: cov-smaj20a-as-built · Status: OPEN

Reason: board-a-baseline confirms the intended net assignment, but incoming reel/body marking, numeric pad orientation and continuity on assembled boards require physical inspection.

Facts in this domain: none are recorded against it.

Blocked by: no blocking fact is recorded. What is missing has not been reduced to a specific recorded fact, so the reason above is the whole of what is known.

Facts

Each fact keeps its value, its unit, the conditions it holds under, where it came from and how far it has been confirmed as separate fields, because they are separate claims. A value without its conditions is not the same fact, and a verdict is about the evidence for the value, not about the part.

GUARANTEED_ELECTRICAL

A parameter the manufacturer guarantees over the stated conditions, usually with minimum, typical and maximum values.

Fact: fact-high-diode-smaj20a-leakage

Value: 5 · Unit: uA

Conditions: maximum IR at VRWM 20 V, TA 25 C

Verdict: PASS - primary-source confirmed · Provenance: PRIMARY-SPEC

Evidence: src-smaj20a-c571370-primary: page 2 exact SMAJ20A row IR and VRWM columns

TRANSIENT

Behaviour during a short event — startup, a switching edge, a fault or a surge.

Fact: fact-high-diode-smaj20a-thermal

Value: 400 · Unit: W

Conditions: 400 W peak pulse power at 10/1000 us waveform, TA=25 C, with the page 5 pulse-duration and ambient-temperature derating curves; not the catalog API PD_mW field

Verdict: PASS - primary-source confirmed · Provenance: PRIMARY-SPEC

Evidence: src-smaj20a-c571370-primary: page 1 PPPM/temperature features and page 5 waveform/derating figures

THERMAL_SOA

Thermal and safe-operating-area behaviour: how much the part may dissipate, and under what mounting and ambient conditions.

Fact: fact-high-diode-smaj20a-temperature

Value: -55 to +150 · Unit: C

Conditions: operating junction and storage temperature range; pulse derating still applies

Verdict: PASS - primary-source confirmed · Provenance: PRIMARY-SPEC

Evidence: src-smaj20a-c571370-primary: page 1 features section operating-junction/storage-temperature row

PROTECTION_STANDOFF

The voltage a protection device is expected to sit at without conducting.

Fact: fact-high-diode-smaj20a-standoff

Value: 20 · Unit: V

Conditions: VRWM exact SMAJ20A row at TA 25 C

Verdict: PASS - primary-source confirmed · Provenance: PRIMARY-SPEC

Evidence: src-smaj20a-c571370-primary: page 2 exact SMAJ20A row VRWM column

PROTECTION_BREAKDOWN

The voltage at which a protection device begins to conduct.

Fact: fact-high-diode-smaj20a-breakdown

Value: 22.2 to 24.5 · Unit: V

Conditions: VBR minimum/maximum at 1 mA, TA 25 C

Verdict: PASS - primary-source confirmed · Provenance: PRIMARY-SPEC

Evidence: src-smaj20a-c571370-primary: page 2 exact SMAJ20A row VBR and IT columns

PROTECTION_CLAMP

The voltage a protection device clamps to while conducting its rated surge current.

Fact: fact-high-diode-smaj20a-clamp

Value: 32.4 · Unit: V

Conditions: maximum VC at IPP 12.3 A, 10/1000 us waveform, TA 25 C; not a universal rail ceiling

Verdict: PASS - primary-source confirmed · Provenance: PRIMARY-SPEC

Evidence: src-smaj20a-c571370-primary: page 2 exact SMAJ20A row VC/IPP and page 5 pulse waveform

PROJECT_STATE

A value this project recorded about how the part is used here — a chosen operating point, a net assignment, or a derived figure. Not a manufacturer specification.

Fact: fact-high-diode-smaj20a-manufacturer

Value: High Diode · Unit: NONE

Conditions: official High Diode SMAJ family document with exact SMAJ20A row

Verdict: PASS - primary-source confirmed · Provenance: PRIMARY-SPEC

Evidence: src-smaj20a-c571370-primary: page 1 title/logo and page 2 SMAJ20A row

Fact: fact-high-diode-smaj20a-identity

Value: lcsc=C571370; manufacturer=High Diode; mpn=SMAJ20A; variant=unidirectional SMA package · Unit: NONE

Conditions: stable distributor identity binding to exact C571370; same-name cross-vendor substitution prohibited; supplies no electrical or thermal authority

Verdict: CONFIRMED - distributor identity only · Provenance: DISTRIBUTOR-IDENTITY

Evidence: src-smaj20a-c571370-distributor: title block and distributor orderable row C571370

Fact: fact-high-diode-smaj20a-polarity

Value: device band marks cathode · Unit: NONE

Conditions: manufacturer marking rule only; project numeric pad mapping is asserted separately in pin-map.json and fact-smaj20a-d5-nets

Verdict: PASS - primary-source confirmed · Provenance: PRIMARY-SPEC

Evidence: src-smaj20a-c571370-primary: page 1 polarity marking statement and page 6 package figure

Fact: fact-smaj20a-d5-nets

Value: D5.1 (cathode) on VBUS_IN; D5.2 (anode) on GND · Unit: NONE

Conditions: board-a fixed circuit per the locked #90/#93 fix list; post-fix topology that replaced the removed D4 (USBLC6-2SC6)

Verdict: NEEDS BENCH · Provenance: PROJECT-CHOICE

Evidence: src-smaj20a-board-a-baseline: nets rows VBUS_IN and GND

Pin maps

The mapping between schematic pins and PCB pads, or physical terminals for an external part, as recorded. A record may carry more than one map when the same part is documented in more than one context.

pinmap-high-diode-smaj20a-c571370

Symbol: SMAJ20A_C571370
Footprint: D-FLAT_L4.3-W2.6-LS5.3-RD
Pins: 2

Pin assignments

Symbol pin	Name	Footprint pad	Function
`1`	`C`	`1`	cathode, D5.1 on VBUS_IN
`2`	`A`	`2`	anode, D5.2 on GND

Interactions

Behaviour that is not a property of this part alone. Each interaction names the records it spans, the conditions it holds under, and how far it has been confirmed. An interaction that spans several parts appears on every one of their pages, under the same identifier, because it is equally a fact about each.

int-high-diode-netlist

Records involved: rec-high-diode-smaj20a-c571370 (this record)
Conditions: board-a-baseline places D5.1 (cathode) on VBUS_IN and D5.2 (anode) on GND: the post-#93-fix topology that replaced the removed D4 (USBLC6-2SC6). Primary polarity/ratings are retained; continuity-check that the assembled D5 orientation matches this net assignment before energization.
Verdict: NEEDS BENCH

Facts this rests on:

fact-high-diode-smaj20a-polarity
fact-high-diode-smaj20a-standoff
fact-high-diode-smaj20a-clamp
fact-smaj20a-d5-nets

int-high-diode-bench

Records involved: rec-high-diode-smaj20a-c571370 (this record)
Conditions: Verify reel label/body marking, numeric pad orientation and continuity, leakage/heating, and the board-a VBUS_IN surge waveform with controlled fixtures; primary table limits do not prove the as-built response.
Verdict: NEEDS BENCH

Facts this rests on:

fact-high-diode-smaj20a-identity
fact-high-diode-smaj20a-polarity
fact-high-diode-smaj20a-leakage
fact-high-diode-smaj20a-thermal

Cross-component rules

Rules that span several parts at once and are published in full on the integration page. Each rule's verdict below is that rule's own — it is a statement about the cross-component question, not about this part — and the exact wording of what the rule refuses to conclude is published with the rule itself.

rule-tvs-clamp-vs-absmax — tvs-clamp-vs-absmax — rule verdict: UNSOURCED

All cross-component rules

Sources

Every document cited above, with its identification, when it was retrieved, and what kind of authority it carries. Sources that could not be retrieved are listed too, with their unavailability stated, so a gap in the evidence is visible rather than absent.

LCSC exact C571370 High Diode SMAJ20A mirror

Source ID: src-smaj20a-c571370-distributor · Authority: DISTRIBUTOR_IDENTITY

Field	Recorded value
Document number	C571370
Revision	static mirror
Document date	not stated
Retrieved	2026-08-02
Printed page	1

Locator: Title block and productCode C571370 exact SMAJ20A row

Availability: AVAILABLE

Document URL: https://datasheet.lcsc.com/datasheet/pdf/491c1abda5fbc387430efce58160a2e0.pdf?productCode=C571370

High Diode SMAJ series transient voltage suppressors

Source ID: src-smaj20a-c571370-primary · Authority: MANUFACTURER_PRIMARY

Field	Recorded value
Document number	SMAJ series
Revision	2025-06
Document date	2025-06-10
Retrieved	2026-08-02
Printed page	2

Locator: Page 1 features/polarity and page 2 exact SMAJ20A electrical row; pages 5-6 waveform/package

Availability: AVAILABLE

Document URL: http://www.h-diode.com/upload/202506/10/202506100145085933.pdf

Board A baseline net-connectivity snapshot

Source ID: src-smaj20a-board-a-baseline · Authority: PROJECT_GENERATOR

Field	Recorded value
Document number	board-a-baseline
Revision	c89c1541fbd6315c9d41fd4f55737368ebcb7bbf
Document date	2026-08-14
Retrieved	2026-08-14
Printed page	source

Locator: nets rows VBUS_IN and GND

Availability: AVAILABLE

Document URL: https://raw.githubusercontent.com/Takazudo/zudo-pd/c89c1541fbd6315c9d41fd4f55737368ebcb7bbf/scripts/schgen/baselines/board-a.json

Legend

What the recorded terms on this page mean, in ordinary words. The exact terms above are the ones that count; these descriptions explain them and never replace them.

Verdict

Recorded term	What it means
`CONFIRMED - distributor identity only`	A distributor listing confirms which part this is, and nothing more. It carries no electrical, thermal or lifetime authority.
`NEEDS BENCH`	Cannot be settled from documents. It needs measurement on real hardware before it can be relied on.
`PASS - primary-source confirmed`	Confirmed against the manufacturer's own document for this exact part.

Provenance

Recorded term	What it means
`DISTRIBUTOR-IDENTITY`	Taken from a distributor listing. Identity information only.
`PRIMARY-SPEC`	Taken from the manufacturer's own specification document.
`PROJECT-CHOICE`	A decision made by this project. No vendor asserts it.

Fact class

Recorded term	What it means
`GUARANTEED_ELECTRICAL`	A parameter the manufacturer guarantees over the stated conditions, usually with minimum, typical and maximum values.
`PROJECT_STATE`	A value this project recorded about how the part is used here — a chosen operating point, a net assignment, or a derived figure. Not a manufacturer specification.
`PROTECTION_BREAKDOWN`	The voltage at which a protection device begins to conduct.
`PROTECTION_CLAMP`	The voltage a protection device clamps to while conducting its rated surge current.
`PROTECTION_STANDOFF`	The voltage a protection device is expected to sit at without conducting.
`THERMAL_SOA`	Thermal and safe-operating-area behaviour: how much the part may dissipate, and under what mounting and ambient conditions.
`TRANSIENT`	Behaviour during a short event — startup, a switching edge, a fault or a surge.

Coverage status

Recorded term	What it means
`COVERED`	Every question this domain asks is answered by the facts listed against it.
`OPEN`	Unresolved. Open means the question has not been answered, not that the part is unsafe — the reason states what is missing.

Source availability

Recorded term	What it means
`AVAILABLE`	The document was retrieved and is on record.

Source authority

Recorded term	What it means
`DISTRIBUTOR_IDENTITY`	A distributor listing. Establishes which part this is, nothing more.
`MANUFACTURER_PRIMARY`	The manufacturer's own document for this exact part.
`PROJECT_GENERATOR`	A document this project generated, such as a schematic or netlist export.

Identity state

Recorded term	What it means
`VERIFIED`	The exact orderable part has been confirmed against a source.

Source state

Recorded term	What it means
`AVAILABLE`	At least one document backing this line was retrieved.

Unit

Recorded term	What it means
`NONE`	The value is not a physical quantity, so it carries no unit. Recorded as `NONE`.

Raw agent resource

This page is generated from a stored evidence bundle and does not restate it. The bundle is the source of truth: where the two ever disagree, the bundle is right and this page is stale.

No owning bundle is identified in the published model.