Smart Espresso Scale
Worked for 23 mins 27 sec
Created a project doc
Layout Verification Notes — Smart Espresso Scale
Board set to compact 50 x 80 mm rounded rectangle. Stackup set to Standard 4 Layer.
Completed the PCB layout pass: the board is 50 × 80 mm, 4-layer, placed with the ESP32 antenna intentionally overhanging the top edge, and fully routed with no airwires/overlap/dangling/invalid-layer errors remaining.
Open items:
- U1 still reports a body-over-edge warning; this is intentional for the ESP32 antenna keepout.
- BOM still needs final MPNs for generic resistors/capacitors, L3 inductor, and J4 header; TP1–TP4 were excluded from BOM/PnP.
- Routing used 0.1 mm traces to enter fine-pitch parts, so power paths should be widened/poured before manufacturing.
I documented the verification details in Layout Verification Notes.
Suggested next steps:
- Select final passive/inductor/header MPNs.
- Widen/pour VBUS, BAT, SYS, REG_IN, and 3V3 power paths.
- Verify antenna keepout visually/mechanically.
- Export Gerbers/BOM/PnP once BOM MPNs are finalized.
Finalize BOM and power
Select final MPNs
Widen power paths
Verify RF keepout
Run manufacture export
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Layout Verification Notes — Smart Espresso Scale
Completed Layout Work
- Board set to compact 50 x 80 mm rounded rectangle.
- Stackup set to Standard 4 Layer.
- Components placed by functional block:
- ESP32-C3 at the top edge with intentional antenna overhang/keepout orientation.
- USB-C, battery, switch, and programming access along the lower edge.
- BQ24074 charger and TPS63031 regulator in the lower/power region.
- HX711 and load-cell connector on the right side, separated from switching power and antenna.
- Routing completed with auto-route after clearing stale routing from placement changes.
Verification Results
- Airwires: clear.
- Overlapping copper: clear.
- Dangling traces: clear.
- Invalid layers: clear.
- Missing footprints: clear.
- Remaining board warning: U1 body extends beyond the top board edge. This is intentional for ESP32-C3 antenna performance; verify the final mechanical outline/enclosure leaves the antenna area unobstructed and copper-free.
BOM / Manufacturing Findings
Remaining manufacturer-part-number issues are sourcing/BOM-finalization items, not layout connectivity problems:
- Generic resistors R1-R21 need final purchasable resistor MPNs or approved house-passive substitution.
- Generic capacitors C1-C16 need final purchasable capacitor MPNs or approved house-passive substitution.
- Generic inductor L3 needs a real 1.5 uH inductor MPN with suitable saturation current, RMS current, DCR, and package.
- J4 I2C OLED header lacks an MPN; select the exact 1x04 2.54 mm header to match the intended display cable/module.
- HX711 has an MPN but no manufacturer field in the BOM metadata; verify preferred supplier/manufacturer before ordering.
- TP1-TP4 were marked excluded from BOM and pick-and-place because they are PCB test pads.
Layout Risks to Review Before Manufacturing
- The global routing width was reduced to 0.1 mm to allow routing into fine-pitch ESD and charger pins. Review high-current paths around USB VBUS, SYS, REG_IN, BAT, and 3V3 before fabrication; widen where feasible or use pours/planes.
- Confirm ESP32 antenna keepout in the final PCB view: no copper, components, mounting hardware, or enclosure metal under/near the antenna zone.
- Confirm L3 footprint and selected inductor dimensions before export.
Completed Layout Work
Verification Results
BOM / Manufacturing Findings
Layout Risks to Review Before Manufacturing
