PLANAR INERTIAL SENSOR, IN PARTICULAR FOR PORTABLE DEVICES HAVING A STAND-BY FUNCTION

A planar inertial sensor includes a first region and a second region of semiconductor material. The second region is capacitively coupled, and mobile with respect to the first region. The second region extends in a plane and has second portions, which face respective first portions of the first region. Movement of the second region, relative to the first region, in any direction belonging to the plane modifies the distance between the second portions and the first portions, which in turn modifies a value of the capacitive coupling.