Patent ID: 8492989

Claim:
A switched-mode power supply for providing electrical supply to a load, comprising: a rectifier having an input and an output, said rectifier being arranged to convert an electrical supply signal provided at its input into a rectified electrical supply signal emerging at its output; an energy storage for storing electrical energy, said energy storage being connectable to said load; a controllable switching element connected to the energy storage, wherein the switching element is arranged to switch the switched-mode power supply between a charging state, in which the energy storage is charged by the rectifier via charge transport from the rectifier, and a discharging state, in which the energy storage releases at least part of electrical energy stored therein to the load; a switching element controller for controlling the switching element, wherein the switching element controller is arranged to control the switching element to switch the switched-mode power supply from the charging state to the discharging state when the charge transport exceeds a current limit; wherein during operation the switched-mode power supply alternates between the charging state and discharging state at a switching frequency which is substantially higher than a frequency of the rectified electrical supply signal, and wherein the current limit is set proportional to an instantaneous voltage of the rectified electrical supply signal.