Design guidelines
PCB design rules
Recommended design parameters for reliable fabrication. Values are confirmed during engineering review.
Trace width & spacing
| 1 oz outer, min trace | 0.10 mm (4 mil) |
| 1 oz outer, min spacing | 0.10 mm (4 mil) |
| 2 oz outer, min trace | 0.16 mm (6.5 mil) |
| 2 oz outer, min spacing | 0.16 mm (6.5 mil) |
| 0.5 oz inner, min trace | 0.09 mm (3.5 mil) |
| Trace width tolerance | ±20% |
Annular ring & drill
| Min annular ring (outer) | 0.13 mm |
| Min annular ring (inner) | 0.15 mm |
| Min drill-to-copper | 0.25 mm |
| Drill hole tolerance (PTH) | +0.13 / -0.08 mm |
| Drill hole tolerance (NPTH) | ±0.05 mm |
| Min castellated hole | 0.50 mm |
Solder mask & silkscreen
| Mask expansion | 0.05 mm per side |
| Min mask bridge | 0.10 mm (green) |
| Mask bridge (black/white) | 0.13 mm |
| Min silkscreen line | 0.15 mm |
| Min text height | 1.0 mm (40 mil) |
| Character width ratio | 1:6 or greater |
Board outline & routing
| Outline layer | Required (GKO / GM1) |
| Route tool diameter | 1.6 mm (standard), 0.8 mm (fine) |
| Board edge clearance | ≥0.3 mm copper to edge |
| V-score | 1/3 thickness remaining |
| Mouse bites | 5 holes, 0.5 mm, 0.8 mm pitch |
| Dimension tolerance | ±0.15 mm |
Impedance & stackup
| Impedance tolerance | ±10% |
| Dielectric constant | 4.2-4.6 (FR-4) |
| Min prepreg thickness | 0.10 mm |
| Min core thickness | 0.10 mm |
| 2-layer stackup | 1.6mm: copper / core / copper |
| 4-layer stackup | Signal / GND / PWR / Signal |
Panelization guidelines
| Min panel border | 10 mm per side |
| Fiducial marks | 1.0 mm dia, 3 per panel |
| Tooling holes | 3.2 mm dia, 4 corners |
| V-score angle | 30° |
| Tab routing | 1.5 mm tab width, 5 tabs per side |
| Max panel size | 450 × 350 mm |
File preparation checklist
✓ Gerber files: RS-274X format. Include all layers (copper, mask, silkscreen, outline, drill).
✓ Drill file: Excellon format (.drl or .txt). Include tool list with sizes.
✓ Board outline: Include on a dedicated mechanical layer or the Gerber outline layer.
✓ BOM: CSV or Excel format. Include reference designator, MPN, manufacturer, quantity, footprint.
✓ CPL (Pick & Place): CSV format. Include designator, X/Y in mm, rotation, side (top/bottom).
✓ Schematic: PDF format for engineering review reference.
✓ ZIP all files: Single archive, max 100 MB.
✓ Naming: Use consistent layer naming — .GTL (top copper), .GBL (bottom copper), .GTS (top mask), .GBS (bottom mask), .GTO (top silkscreen), .GBO (bottom silkscreen), .GKO (outline), .TXT (drill).