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- For 2-layer boards, all vias >= 0.3mm hole, 0.6mm diameter
- For 4-layer boards, all vias >= 0.2mm hole, 0.45mm diameter
- Make sure vias do not interfere with internal layers (DRC should catch this)
- Thermal vias should be small and numerous - we want the greatest surface area between planes as possible
- For critical power traces, use multiple vias in parallel to reduce inductance and resistance
- In general for vias, make the diameter 2x the size of the hole.
Board - Layers
- Make sure there is a keep out layer surrounding your board.
- Make sure all these layers are selected when generating your gerbers.
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