A POWER SUPPLY
A power supply (1) for an electronic device comprising electric cells (7) arranged to generate an intermediate voltage (Vx), and a voltage converter (30) coupled to the electric cells (7), the voltage converter (30) converting the intermediate voltage (Vx) to an output voltage (Vo), wherein the converter (30) comprises a switch (14) to vary the output voltage (Vo) to match an input voltage of the electronic device.