Patent ID: 8474317

Claim:
A microelectromechanical device comprising: a body; a movable mass, elastically connected to the body and oscillatably movable with respect to the body according to a degree of freedom; a driving device coupled to the movable mass so as to form a microelectromechanical loop and configured to keep the movable mass in oscillation with a steady operating frequency in a normal operating mode; and a start-up device activatable in a start-up operating mode and configured to compare a current oscillation frequency of a first signal correlated to oscillation of the movable mass with a reference frequency and to selectively transfer energy to the movable mass by providing the movable mass with a forcing signal packet, based on a comparison between the current oscillation frequency and the reference frequency, wherein: the start-up device is configured to provide the movable mass with one forcing signal packet in response to determining that the current oscillation frequency is outside an acceptable range including the reference frequency; the driving device comprises a PLL circuit; and the start-up stage is configured to disable the PLL circuit when the current oscillation frequency is outside the acceptable range relative to the reference frequency and to enable the PLL circuit otherwise.