A method for regulating the activity of a core running at a given clock rate, the method comprising: - monitoring a value of a parameter of the core, the parameter being a critical parameter for a safe operating of the core; - determining whether the monitored value reaches a trigger value; - when the monitored value reaches the trigger value: ∘ modifying the clock rate of the core by decreasing the ratio of active cycles of the clock; and ∘ running the core at the clock rate modified by decreasing the ratio of active cycles of the clock; - when the monitored value reaches a second time the trigger value: ∘ modifying the clock rate of the core by increasing the ratio of active cycles of the clock; and ∘ running the core at the clock rate modified by increasing the ratio of active cycles of the clock wherein, when the monitored value reaches the trigger value, the steps of modifying the clock rate and running the core at the modified clock rate are repeated until the monitored value reaches the second time the trigger value, characterized in that the repetition of the steps of modifying the clock rate and running the core at the modified clock rate until the monitored value reaches the second time the trigger value comprises: - counting a number of cycles carried out by the clock of the core that runs at the clock rate modified by decreasing the ratio of active cycles of the clock; - modifying the clock rate by, once more, decreasing the ratio of active cycles of the clock when the number of cycles counted reaches a predetermined value; - running the core at the clock rate modified by, once more, decreasing the ratio of active cycles of the clock; wherein the trigger value is dynamically determined according to at least one of the following: - the decrease of the ratio of active cycles of the clock; - the increase of the ratio of active cycles of the clock; - a reaction time between the determining step and the clock rating step. - monitoring a value of a parameter of the core, the parameter being a critical parameter for a safe operating of the core; - determining whether the monitored value reaches a trigger value; - when the monitored value reaches the trigger value: ∘ modifying the clock rate of the core by decreasing the ratio of active cycles of the clock; and ∘ running the core at the clock rate modified by decreasing the ratio of active cycles of the clock; ∘ modifying the clock rate of the core by decreasing the ratio of active cycles of the clock; and ∘ running the core at the clock rate modified by decreasing the ratio of active cycles of the clock; - when the monitored value reaches a second time the trigger value: ∘ modifying the clock rate of the core by increasing the ratio of active cycles of the clock; and ∘ running the core at the clock rate modified by increasing the ratio of active cycles of the clock ∘ modifying the clock rate of the core by increasing the ratio of active cycles of the clock; and ∘ running the core at the clock rate modified by increasing the ratio of active cycles of the clock - counting a number of cycles carried out by the clock of the core that runs at the clock rate modified by decreasing the ratio of active cycles of the clock; - modifying the clock rate by, once more, decreasing the ratio of active cycles of the clock when the number of cycles counted reaches a predetermined value; - running the core at the clock rate modified by, once more, decreasing the ratio of active cycles of the clock; - the decrease of the ratio of active cycles of the clock; - the increase of the ratio of active cycles of the clock; - a reaction time between the determining step and the clock rating step.