Again beginner doubts. I am designing a prototype PCB to facilitate the assembly (I would prefer to wait for the Ferduino Mega plate if possible its availability).
The schematic of the connection of the PCF8575 module and the integrated ULN2803A is that of the attached drawing. From what I have read (many of the images of photobucklet have disappeared) I think it is correct but the doubt that I have is if it would not be convenient to feed with 5V the common pin (10) of the ICs.
Thanks