Patent ID: 9153987
Filing Date: 2015-10-06
Classification: H02J

Abstract:
1. A method for controlling a system voltage generated by a battery charger circuit in a battery-operated electronic device, the battery charger circuit being configured to generate output voltages for powering the internal circuitry of the electronic device and for charging the battery of the electronic device, the method comprising: connecting the battery charger circuit to an input power source; generating, at the battery charger circuit, the system voltage at a system voltage node to supply internal circuitry of the electronic device and a battery voltage at a battery voltage node for recharging a battery of the electronic device; accessing an available current supplied by the input power source; accessing a battery voltage of the battery; determining whether the input power source is current limited based on the available current, wherein the input power source is current limited when the input power source is not derived from an AC power source; determining whether the battery is deeply depleted or missing based on the battery voltage; in response to the determining that the input power source is current limited and the determining that the battery is deeply depleted or missing, electrically isolating the battery voltage node from the system voltage node so that no voltage is provided to the battery and the battery is not being recharged, and further setting the system voltage to an elevated voltage value greater than a nominal battery voltage value; and supplying the elevated system voltage to the internal circuitry of the electronic device to boot up the electronic device.