NEMA17 PCB Design Optimization
Thought
Work completed
- U2: footprint set to QFN-28 EP 5×5 mm, 0.5 mm pitch
- U3 and U4: footprints set to SOIC-8 3.9 mm
- U5: footprint set to SOIC-8-EP 4.9×6.0 mm
- PCB outline changed to 42.3 mm × 42.3 mm
- Added four M3 mounting holes: Hole1, Hole2, Hole3, Hole4 at ±15.5 mm
- Project property “Stackup” set to JLC 2-layer 1 oz
- Project property “Copper Planes” set to bottom solid GND
Tasks not done
- Modify footprint of U1 to LQFP-48 0.5 mm pitch
- Add a 22 mm diameter copper keep-out region
- Add a 26 mm tall-part keep-out region
- Center U3 and add bullseye silkscreen overlay
- Add thermal-via arrays under the exposed pads of U2 and U5
- Validate EMC separation (CAN di/dt areas, sensor isolation, CAN-pair clearance, decoupler placement)
- Run ERC and DRC checks and document violations
Success criteria review
- Footprints for U2–U5: ✅ met, U1 still pending
- Board outline & four M3 holes: ✅ outline and holes done, central keep-outs missing
- U3 centering & bullseye: ❌ not done
- 2-layer 1 oz stackup & bottom GND plane: ✅ met
- PGND islands, stitching vias & sensor no-copper donut: ❌ not implemented
- Thermal vias & EMC separation: ❌ not implemented
- ERC/DRC violations cleared: ❌ not performed
Next step
Implement the mechanical keep-outs (22 mm copper, 26 mm tall-part) and center U3 with a bullseye silkscreen marker.
proceed
Thought for 1 min 31 sec
I’ll proceed with your requested updates. Plan to run now:
-
Mechanics: keep 42.3 mm outline; 4×M3 @ 31 mm; add Ø22 mm copper and Ø26 mm tall‑part keep‑outs; center U3 with bullseye silk.
-
Thermal/EMC: add EP thermal via arrays; maintain CAN pair clearance from switching loops; tighten decouplers to pins.
-
Verify: run ERC/DRC and resolve issues; report deltas.
Click Start on the plan bar to execute.
Add CAN test pads
Place fiducials
Enable teardrops
Reposition SWD header
Select decoupling caps
To get started, talk to Flux or create a New Document.
