A microelectromechanical sensor device , comprising a detection structure and an associated electronic circuitry ; wherein said electronic circuitry is configured to receive, when said microelectromechanical sensor device is powered, an external power supply voltage (V DD ) and comprises a voltage regulator configured to generate a regulated voltage (V REG ) having a value different from said external power supply voltage (V DD ) and at least one voltage domain powered by said regulated voltage (V REG ), characterized in that said voltage domain comprises a switching control logic and a number of sub-domains , distinct from each other and selectively controllable in power-on or power-off by said switching control logic ; and in that said electronic circuitry comprises a power supply management core , always powered by said external power supply voltage (V DD ) and configured to control said voltage regulator to selectively interrupt the power supply of said voltage domain to implement: a first power-down condition of said microelectromechanical sensor device wherein said voltage regulator is disabled; and a second power-down condition of said microelectromechanical sensor device wherein said voltage regulator is enabled to power said voltage domain through said regulated voltage (V REG ) and said switching control logic is configured to interrupt power supply of one or more of said sub-domains to reduce a power consumption of said microelectromechanical sensor device , said first and second power-down conditions being associated with absence of data acquisition by said microelectromechanical sensor device , wherein said power supply management core is configured to automatically alternatively enable said first or said second power-down condition upon a first power-on of said microelectromechanical sensor device , as a function of a configuration signal (S conf ). characterized in that said voltage domain comprises a switching control logic and a number of sub-domains , distinct from each other and selectively controllable in power-on or power-off by said switching control logic ; and in that said electronic circuitry comprises a power supply management core , always powered by said external power supply voltage (V DD ) and configured to control said voltage regulator to selectively interrupt the power supply of said voltage domain to implement: a first power-down condition of said microelectromechanical sensor device wherein said voltage regulator is disabled; and a second power-down condition of said microelectromechanical sensor device wherein said voltage regulator is enabled to power said voltage domain through said regulated voltage (V REG ) and said switching control logic is configured to interrupt power supply of one or more of said sub-domains to reduce a power consumption of said microelectromechanical sensor device , said first and second power-down conditions being associated with absence of data acquisition by said microelectromechanical sensor device , wherein said power supply management core is configured to automatically alternatively enable said first or said second power-down condition upon a first power-on of said microelectromechanical sensor device , as a function of a configuration signal (S conf ). <EOS>