A power electronics device has a first power semiconductor switch and a driver circuit and enables a supply of electrical voltage to a driver circuit. An auxiliary circuit arrangement has a supply capacitor, an auxiliary capacitor, a normally off auxiliary semiconductor switch, a diode and a bootstrap diode. The auxiliary semiconductor switch is connected to a reference potential connection of the first power semiconductor switch via a connection point, starting from the connection point, a series connection of the diode, a second connection point and the auxiliary capacitor is arranged in parallel with the auxiliary semiconductor switch. When the auxiliary semiconductor switch is in the off state, the auxiliary capacitor is charged by the flow of current through the first power semiconductor switch.