Design board protections

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Designing protections

We should include protection schematics ready to be included in new projects to ensure maximum reliability.

I suggest that every board we design contain this small schematic (the left one) on the power input :

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Is it a good idea to put resistors on each input/output of the micro-controller ? They should limit the current going through them, just like in TP...

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For the coupling capacitors I found ours to be quite big (470 µF is a lot) and it seems that we could use a little bit less.

Most engineers will place 100nF X7R capacitors as close as possible to the IC's power pins. One capacitor per power pin. A good IC pinout will have a ground pin next to each power pin, so you can keep the loop as short as possible.

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[dotsumae]

K for reducing coupling capacitors. 470uF is overkill and even possibly unefficient after some researches.
I am currently working on the reverse voltage issue using this video
EDIT : This video is interesting for it explains how we can avoid using a zener diode (high power losses) by choosing the right MOSFET