Part Audit Review
Worked for 1 min 14 sec
The part already has an official ST datasheet URL. I’m now validating every pin and the Flexiwatt25 footprint against that document.
Worked for 4 mins 49 sec
Created a project doc
Part Audit
Part Audit
Scope
Audit of the published TDA7850 part metadata, schematic symbol, Flexiwatt25 vertical footprint, and pin descriptions against the official STMicroelectronics datasheet.
Authoritative source
- MPN: TDA7850
- Manufacturer: STMicroelectronics
- Official datasheet: https://www.st.com/resource/en/datasheet/tda7850.pdf
- Datasheet revision reviewed: Rev. 6, September 2013
- Package variant: Flexiwatt25 (vertical); the horizontal package is associated with TDA7850H.
The Datasheet URL property was already populated with the official ST URL, so no property update was necessary.
Existing part metadata
Key specifications
- Four-channel Class-AB automotive audio power amplifier with four BTL outputs.
Audit complete. The existing Datasheet property already points to the official STMicroelectronics PDF, so no update was required.
Key issues: the description incorrectly says stereo instead of four-channel/quad; four positive BTL outputs omit
+; pin 20 is labeled VCC_1; all pin types and descriptions are unspecified; and the footprint’s drill, annular ring, orientation, and STEP alignment need physical validation before manufacturing. Full specifications and findings are in the Part Audit.Fix symbol and metadata
Validate footprint geometry
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Part Audit
Scope
Audit of the published TDA7850 part metadata, schematic symbol, Flexiwatt25 vertical footprint, and pin descriptions against the official STMicroelectronics datasheet.
Authoritative source
- MPN: TDA7850
- Manufacturer: STMicroelectronics
- Official datasheet: https://www.st.com/resource/en/datasheet/tda7850.pdf
- Datasheet revision reviewed: Rev. 6, September 2013
- Package variant: Flexiwatt25 (vertical); the horizontal package is associated with TDA7850H.
The Datasheet URL property was already populated with the official ST URL, so no property update was necessary.
Existing part metadata
Table
| Field | Observed value | Audit |
|---|---|---|
| MPN | TDA7850 | Correct |
| Manufacturer | STMicroelectronics | Correct |
| Description | TDA7850, Audio Amplifier Class-AB stereo 25-Pin FLEXIWATT | Incorrect: device is a four-channel/quad bridge amplifier, not stereo |
| Pin count | 25 | Correct |
| Package | Description says 25-Pin FLEXIWATT; footprint says Flexiwatt25 vertical | Correct variant, but no explicit Package property |
| Datasheet URL | Official ST PDF | Correct |
Key specifications
- Four-channel Class-AB automotive audio power amplifier with four BTL outputs.
- Fully complementary MOSFET output stages; internally fixed gain of 26 dB typical.
- 14.4 V typical characterization supply; 18 V maximum operating supply, 28 V DC absolute maximum, and 50 V peak for 50 ms.
- Output power: 4 x 30 W typical into 4 ohm at 14.4 V, 1 kHz, 10% THD; 4 x 55 W typical into 2 ohm under the same conditions.
- Maximum-power figures of 50 W/4 ohm and 85 W/2 ohm use saturated square-wave conditions and are not continuous low-distortion audio ratings.
- THD: 0.006% typical at 4 W; output noise 35 uV typical A-weighted.
- Quiescent current: 180 mA typical.
- Integrated standby, mute, supply automute, soft thermal limiting, short-circuit/load-dump/reverse-battery protection, 0.35 A high-side driver, and output DC-offset diagnostics.
- Maximum junction temperature: 150 C; junction-to-case thermal resistance: 1 C/W maximum.
Pin cross-check
All 25 pin numbers map to the correct functions and ordering, but the following names differ from the official datasheet:
Table
| Pin | Current name | Official name | Finding |
|---|---|---|---|
| 5 | OUT2 | OUT2+ | Missing positive BTL polarity suffix |
| 9 | OUT1 | OUT1+ | Missing positive BTL polarity suffix |
| 17 | OUT3 | OUT3+ | Missing positive BTL polarity suffix |
| 20 | VCC_1 | VCC | Artificial suffix may imply a separate rail |
| 21 | OUT4 | OUT4+ | Missing positive BTL polarity suffix |
All four loudspeaker connections are bridge outputs. Neither speaker terminal may be connected to ground.
Pin metadata deficiencies
- Every terminal has
Pin Type = Unspecified; therefore ERC cannot distinguish power inputs, grounds, analog inputs, control inputs, or high-current outputs. - Every pin description is empty.
- Pin 25 HSD should document both functions: high-side driver output and DC-offset diagnostic indication.
- When HSD is used for offset detection, the datasheet requires a 10 kohm pulldown to ground.
- Pins 6 and 20 are the same VCC rail.
- TAB, SVR, AC-GND, ST-BY, and MUTE require functional descriptions to prevent misuse.
Footprint cross-check
Confirmed matches
- 25 plated through-hole pads numbered 1 through 25.
- Staggered pin arrangement with 1.00 mm adjacent-pin pitch and 24.00 mm overall lead-array span, matching the nominal Flexiwatt25 mechanical drawing.
- Approximate body envelope of 29.30 x 4.65 mm matches datasheet maximum body dimensions.
- Pin 1 uses a rectangular marker.
Risks and unresolved items
- The ST datasheet provides package mechanical dimensions but no recommended PCB land pattern or finished-hole specification.
- The 4.4 mm footprint row spacing is plausible but was not conclusively tied to a PCB-hole datum in the datasheet.
- A 0.72 mm finished hole may be tight against lead size and insertion/plating tolerances.
- The 1.12 mm pad with 0.72 mm drill gives only a 0.20 mm nominal annular ring, leaving limited registration margin.
- Uniform small pads provide limited mechanical and current-carrying attachment for VCC, power-ground, and BTL output pins.
- No explicit heatsink/chassis assembly keepout or full vertical package envelope is represented.
- The STEP model is attached at unit scale and zero offset, but lead-to-hole alignment, seating plane, vertical-package identity, and top-view orientation remain unverified.
- Footprint pin-1 orientation must be visually checked against the datasheet top-view drawing to rule out mirroring.
Mismatch severity
Definite
- Part description incorrectly says stereo instead of quad/four-channel.
- Four positive BTL output pins omit the
+suffix. - Second supply pin is labeled
VCC_1rather thanVCC. - All pin electrical types are unspecified.
- All pin descriptions are missing.
Manufacturing/usage risks
- Drill and annular-ring margins need validation against the actual lead tolerance and chosen PCB fabricator.
- High-current/mechanical pad sizing should be reviewed.
- Heatsink clearance and mounting strategy are not captured by the footprint courtyard.
- STEP-model and footprint orientation/alignment are not proven.
- Missing polarity suffixes create a material risk of incorrect BTL speaker wiring.
Recommended corrections
- Change the description to identify a 4-channel/quad BTL Class-AB automotive audio amplifier.
- Rename pins 5, 9, 17, and 21 to
OUT2+,OUT1+,OUT3+, andOUT4+. - Present pin 20 as the second physical
VCCpin without implying a separate supply. - Assign ERC electrical roles and add datasheet-grounded descriptions to every pin.
- Verify the physical footprint with a measured production part or a qualified land-pattern source before manufacturing, especially drill diameter, annular ring, row spacing, and orientation.
- Verify the STEP model against pad centers and the board seating plane.
Scope
Authoritative source
Existing part metadata
Key specifications
Pin cross-check
Pin metadata deficiencies
Footprint cross-check
Confirmed matches
Risks and unresolved items
Mismatch severity
Definite
Manufacturing/usage risks
Recommended corrections
