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- All power input connectors are 2-pin Molex Micro Fit (with the correct GND/PWR orientation)
- Unless higher current is required, under special circumstances
- Easy attachment point for an oscilloscope probe GND - test points with the 'test point' part from digikey work well
- Make sure there are enough GND test points!
- Headers and pins for all communication protocols - for now, 0.1" headers, to standardize on a debug connector
- I2C
- SPI
- etc
Board - Vias
- 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.
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