An integrated circuit includes a substrate. A fixed main capacitor electrode is disposed in a metal layer overlying the substrate. A second main capacitor electrode is disposed in a metal layer and spaced from the fixed main capacitor electrode. A movable capacitor electrode is disposed adjacent the fixed main capacitor electrode. The movable capacitor electrode is switchable between a first configuration in which the movable capacitor electrode and fixed main capacitor electrode are mutually spaced out in such a manner as to form an auxiliary capacitor electrically connected to the main capacitor. In a second configuration, the movable capacitor electrode and the fixed main capacitor electrode are in electrical contact in such a manner as to give a second capacitive value.