The present invention relates to a timepiece comprising: a mechanical power source coupled to a time indicating display, a generator, wherein the mechanical power source is coupled to the generator, a regulator circuit configured for enslaving a generator frequency of the generator to a reference frequency, wherein the regulator circuit is configured for electrically braking the generator when the generator frequency is higher than the reference frequency, wherein the regulator circuit comprises: at least a first switch, at least a first inductor and at least a first capacitor, wherein the first switch and the first capacitor are arranged parallel to each other and wherein the first switch and the first capacitor are arranged in series with the first inductor.