Yes, it might revert to the screen timeout that you have set.
There are some apps that can keep your screen on, but remember that this will drain your battery.
Probably the best method is to open Developers Options and use the Stay Awake feature.
This will let the screen dim after the set timeout, but it will not go completely off.
It will only be active while the phone is charging, so it will not drain the battery.
This is especially useful in the car, both during calls and for playing music.