"Smart" charger : Main board

The first part is a sort of generic main board including : Arduino nano, ST7735 screen, level translators for the screen, usb input, and easy to connect Axxx and Dxxx lines

Nothing special here

The couple of mandatory pics :









At first i had problem with the screen, that looked dim
It appears that powering the screen through the arduino is not a good idea.
That's why there is a separate micro USB connector that powers everything (not sure it can handle "high" current as it is a micro usb to DIP adapter board with rather thin tracks).


That main board then connects to a daughter board, sending it power + Axxx lines + Dxxx lines


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