I am a bit confused as to what you are asking.
The arduino has a built in power regulator that cuts the jack socket voltage down to 5V. You can't put a higher voltage into the pins or switch a higher voltage without using a transistor.
I am a bit confused as to what you are asking.
The arduino has a built in power regulator that cuts the jack socket voltage down to 5V. You can't put a higher voltage into the pins or switch a higher voltage without using a transistor.