Part Audit Review
Worked for 2 mins 30 sec
Scope status: Completed audit; no mutation required.
Inspected evidence
- Part: MCH3478-TL-H
- Manufacturer: ON Semiconductor / onsemi — matches datasheet
- MPN: MCH3478-TL-H — matches
- Description: “MOSFETs NCH 1.8V DRIVE SERIES” — broadly correct but incomplete
- Package: MCPH3; equivalent SC-70/SOT-323
- Pin count: 3
- Project properties: Datasheet URL, Designator Prefix
Q, Manufacturer Part Number, Manufacturer Name - Existing Datasheet property: populated with an uploaded PDF, so per instruction it was not changed
- Current official onsemi URL:
https://www.onsemi.com/download/data-sheet/pdf/ena1353-d.pdf
- N-channel, single power MOSFET
- VDSS: 30 V
- VGSS: ±12 V
- ID: 2 A DC; 2.5 A for ≤10 s at ≤1% duty; 8 A pulse for ≤10 µs at ≤1% duty
- RDS(on):
- 125 mΩ typ / 165 mΩ max at VGS=4.5 V, ID=1 A
- 165 mΩ typ / 235 mΩ max at VGS=2.5 V, ID=0.5 A
- 250 mΩ typ / 375 mΩ max at VGS=1.8 V, ID=0.3 A
- Threshold/cutoff voltage: 0.4–1.3 V at VDS=10 V, ID=1 mA
- Power dissipation: 0.8 W DC; 1.2 W for 10 s, both on specified 900 mm² × 0.8 mm ceramic substrate
- Channel temperature: 150 °C
- Storage: −55 to +150 °C
- No explicit θJA value was found; thermal capability is substrate-dependent.
- Exact mapping: pin 1 Gate, pin 2 Source, pin 3 Drain
All three terminal numbers exist, but:
- Pins 1, 2, and 3 are all named
~ - All are typed
Unspecified - Pin descriptions are absent
- Pin groups, sections, and terminal ordering are absent
Thus the symbol does not identify Gate, Source, or Drain despite having the correct numeric pins. The rendered custom symbol is also a plain rectangular body rather than a recognizable N-MOSF symbol.
Footprint findings
- Three rectangular SMD pads, logically associated with pins 1–3
- Pad centers from footprint source:
- 1: (−1.062, −0.65) mm
- 2: (−1.062, +0.65) mm
- 3: (+1.062, 0) mm
- Each pad: 0.500 × 0.525 mm, rotated 90°
- Fabrication body outline: 1.6 × 2.0 mm
- Courtyard: 2.95 × 2.30 mm
- 3D STEP model is present.
- Datasheet package is approximately 2.1 × 2.0 × 0.85 mm, 0.65 mm pitch.
- Datasheet land-pattern example specifies 0.4 × 0.6 mm lands. The stored 0.500 × 0.525 mm pads therefore do not match the recommended land geometry.
- Flux pad labels display as
~; numbering is only recoverable through terminal UID association.
- Unattempted/not applicable: Datasheet update, because the property was already non-empty.
- No symbol, footprint, or other properties were altered.
No. The numeric pin mapping appears recoverable and correct, but the unnamed/untyped symbol terminals create a substantial connection-error risk, and the footprint pad geometry differs from the official recommended land pattern. The part should be corrected and footprint-validated before production use.
Thought for 14 sec
The audit is complete: the datasheet was already present, and the main issues are unnamed/untyped symbol pins plus footprint lands that differ from onsemi’s recommendation. I’m recording the detailed findings now.
Worked for 1 min 20 sec
Created a project doc
MCH3478-TL-H Part Audit
Manufacturer: onsemi / ON Semiconductor — matches official datasheet MPN: MCH3478-TL-H — matches official datasheet
Audit complete. The datasheet was already populated, so it was not changed; metadata is broadly correct, but the symbol lacks Gate/Source/Drain names and types, and the footprint lands differ from onsemi’s recommendation. The part is not production-ready as-is, and I filed an internal quality report.
Full specifications and findings: MCH3478-TL-H Part Audit
Fix and recheck part
Fix symbol pins
Correct footprint lands
Update description
Run part review
Refine this doc
Ask about this doc
MCH3478-TL-H Part Audit
Audit status
- Manufacturer: onsemi / ON Semiconductor — matches official datasheet
- MPN: MCH3478-TL-H — matches official datasheet
- Description:
MOSFETs NCH 1.8V DRIVE SERIES— broadly correct, but incomplete - Package: MCPH3, a 3-pin SC-70/SOT-323-class package
- Pin count: 3 — correct
- Datasheet property: already populated with an uploaded PDF; no update was made
- Current official datasheet: https://www.onsemi.com/download/data-sheet/pdf/ena1353-d.pdf
Key specifications
Table
| Parameter | Datasheet value |
|---|---|
| Device type | Single N-channel power MOSFET, 1.8 V gate-drive series |
| Drain-source voltage, VDSS | 30 V |
| Gate-source voltage, VGSS | ±12 V |
| Continuous drain current, ID | 2 A |
| Limited-duration drain current | 2.5 A, ≤10 s, ≤1% duty |
| Pulsed drain current | 8 A, ≤10 µs, ≤1% duty |
| RDS(on), VGS = 4.5 V, ID = 1 A | 125 mΩ typ, 165 mΩ max |
| RDS(on), VGS = 2.5 V, ID = 0.5 A | 165 mΩ typ, 235 mΩ max |
| RDS(on), VGS = 1.8 V, ID = 0.3 A | 250 mΩ typ, 375 mΩ max |
| Gate threshold / cutoff voltage | 0.4–1.3 V at VDS = 10 V, ID = 1 mA |
| Power dissipation | 0.8 W DC; 1.2 W for 10 s on specified ceramic substrate |
| Maximum channel temperature | 150 °C |
| Storage temperature | −55 to +150 °C |
| Pin 1 | Gate |
| Pin 2 | Source |
| Pin 3 | Drain |
Thermal capability is strongly dependent on the specified 900 mm² × 0.8 mm ceramic test substrate. No explicit junction-to-ambient thermal resistance was identified in the audited datasheet information.
Schematic symbol cross-check
The symbol contains numeric pins 1, 2, and 3, but all three are named
~, typed Unspecified, and have no descriptions. Functional groups, sections, and terminal ordering are also absent.Mismatch
Table
| Pin | Datasheet function | Current symbol name/type |
|---|---|---|
| 1 | Gate | ~ / Unspecified |
| 2 | Source | ~ / Unspecified |
| 3 | Drain | ~ / Unspecified |
The custom symbol is a plain rectangular body rather than a recognizable N-channel MOSFET symbol. Although the pin numbers exist, the missing functional names and electrical types create a significant wiring-error risk.
Footprint cross-check
- Three rectangular SMD pads are present and associated with pins 1–3.
- Pad centers: pin 1 at (−1.062, −0.65) mm; pin 2 at (−1.062, +0.65) mm; pin 3 at (+1.062, 0) mm.
- Stored pad size: 0.500 × 0.525 mm, rotated 90°.
- Fabrication body outline: 1.6 × 2.0 mm.
- Courtyard: 2.95 × 2.30 mm.
- A STEP model is present.
- Datasheet package dimensions are approximately 2.1 × 2.0 × 0.85 mm, with 0.65 mm pitch.
- The official land-pattern example specifies approximately 0.4 × 0.6 mm lands.
Mismatch
The stored 0.500 × 0.525 mm pads do not match the official 0.4 × 0.6 mm recommended land dimensions. Pad numbering also renders as
~ in Flux and is only recoverable from terminal UID association, reducing reviewability.Conclusion
The part should not be treated as production-ready as-is. The MPN, manufacturer, pin count, broad package class, and numeric pin mapping are consistent with the datasheet. However, the symbol lacks Gate/Source/Drain names, descriptions, and electrical types, and the footprint pad geometry differs from onsemi’s recommended land pattern. Correct and revalidate the symbol and footprint before production use.
Audit status
Key specifications
Schematic symbol cross-check
Mismatch
Footprint cross-check
Mismatch
Conclusion
