Expert Opinion - Query 23 (GPIO of Raspberry Pi)

What electrical levels are accepted on the Raspberry Pi GPIO?

There are in total Raspberry Pi supports 3.3V GPIO pins. Any voltage above 2 on GPIO is treated as logic HIGH and any voltage below 2V is treated as logic LOW. 

The current drive capability of Raspberry GPIO is max. of 16mA. This configuration has to be set, else default current drive capability is 8mA Max.