A power transistor has a first current electrode coupled to a first power supply terminal and a second current electrode as an output of the circuit. A driver control circuit is coupled between a first and a second internal power supply node and is coupled to a control electrode of the power transistor. A first switch selectively couples the first power supply terminal to the first internal power supply node. A second power supply terminal is coupled to the second internal power supply node. A diode has an anode coupled to the second internal power supply node. A second switch is coupled between the diode and the output of the circuit such that, when the circuit is in active mode, it selectively couples the cathode of the diode to the output of the circuit based on whether or not the second power supply terminal is coupled to an external ground.