A Hall sensor device includes a Hall effect region of a first conductivity type, electrical contact regions configured to provide electrical signals to/from the Hall effect region, and circuitry. Each electrical contact region is formed in a respective well of a second conductivity type that adjoins the Hall effect region. Circuitry includes control terminals, wherein each control terminal is configured to control a conductance in an associated well of the second conductivity type. The circuitry is configured to selectively apply control signals to a first subset of the control terminals to form channels conducting majority carriers of the first conductivity type in the associated wells during a first operating phase, and to selectively apply control signals to a second subset of the control terminals to form channels conducting majority carriers of the first conductivity type in the associated wells during a second operating phase.