Hello , good afternoon , i´d be thankful if you could help me with a project that I am developing . I need to control two types of 7-segment cathode display : a 2 ' (HS-23101AS) and 4' (HS-40101AS) , using the Arduino MEGA and the shift register MAX7219 , but I have doubts of how to implement , because of the voltage limitation of the shift register and the voltage necessary to the displays ... what should I do ?