This disclosure describes techniques for operating a corded electronic device in which a battery and a power control unit manage power draw from an external power source electrically coupled to the corded electronic device using a physical cord, such as a universal serial bus (USB) cable. The power control unit automatically supplements an electrical current continuously drawn by the corded electronic device from the external power source with an electrical current from the battery, when needed. Moreover, the power control unit operates to limit the current drawn from the external power source and the physical cord so as to ensure the current does not exceed any limitations or requirements associated with the external power source or the physical cord.