A microsystem consists of at least one sensor and/or actuator, a signal processor and/or control mechanism linked therewith, a timer, and an electrical energy storage unit providing a current source for at least the signal processor and/or control mechanism. The signal processor and/or control mechanism has a mode switching mechanism, by means of which it can be set to an operating mode and a resting mode that consumes less current compared with the operating mode. The mode switching mechanism has at least one control signal input which is electrically connected to the timer for application of a mode switching signal. The timer is a mechanical timer, which has at least one micromechanical cantilever, which is coupled with at least one electrical element connected to the at least one control signal input of the signal processor and/or control mechanism in such a way that said electrical element is time-dependently set.