A voltage regulator having an output terminal adapted to being connected to a load, including an operational amplifier having its non-inverting input connected to a reference voltage, and its inverting input connected to the output terminal, an inverting amplifier having its input connected to the output of the operational amplifier, a capacitive impedance connected between the input and the output of the inverting amplifier, a power switch controlled by the output of the inverter amplifier, arranged to connect the output terminal to a first supply voltage, said capacitive impedance including a short-circuitable portion associated with active short-circuit means when the current flowing through the load is greater than a predetermined current.