In this application you typically use p-ch mosfets with gate pulled down to turn on, a resistor will provide pull-up of the gate to turn off. So Ugs is the sam

In this application you typically use p-ch mosfets with gate pulled down to turn on, a resistor will provide pull-up of the gate to turn off. So Ugs is the same as the rail voltage (3.3, 5 and 12v).