This page gives advices that I have collected as a result of my experience in designing and making hardware systems. I do not pretend this is the best practices in the area. I use this as a set of notes to follow when I'm designing a new board.
Schema design
Verify the following items:
- unused pins
- connector layout (for routing, evolutions, understanding, isolation)
- decoupling with capacitors
- protection of power supply
- control logic to validate
- do not neglect the pull up resistors
PCB design
Verify and take care of the following items:
- global positioning of components. There must be enough space between them so that I can solder, repair them.
- components should be aligned. This simplifies the power supply routing, the mounting.
- Ground layout
- Vcc layout
- enlarge the width of wires (keep it to the max). I try not to go below 0.4mm (16 mil)
- enlarge the clearance to the maximum. 0.4mm (16 mil) for wire, 0.25 (10 mil) for pads and wire
- run the Eagle DRC check with a larger clearance and fix the problems.
- assign a specific Class for the power supply lines and setup that class with a larger width 0.8mm