The present disclosure relates to a device comprising an inductive element and a first capacitive element series connected between a first node and a second node, a first MOS transistor connected between the first node and a third node configured to receive a reference potential, the second node being coupled directly or via a second MOS transistor to the third node, a second capacitive element connected between a fourth node and an interconnection node between the first capacitive element and the inductive element, a current generator configured to provide an AC current to the fourth node, and a switch connected between the fourth node and the third node.