Patent ID: 7548041

Claim:
For a battery powered application, a power management method for providing power to both a load and a battery, comprising steps of: generating a battery-charging control current with a magnitude variable in accordance with an input current and a load current; supplying a charging current to the battery for a charging period determined by a timer duration to charge the battery from a discharged state to a charged state, the charging current being controlled in accordance with the magnitude of the battery-charging control current; generating a clock signal with a frequency variable in accordance with the magnitude of the battery-charging control current; and counting the timer duration based on the clock signal, wherein the timer duration is variable in accordance with the frequency of the clock signal being variable in accordance with the magnitude of the battery-charging control current, wherein the step of generating the clock signal includes charging and discharging a capacitor with a capacitor-charging current having a magnitude variable in accordance with the magnitude of battery-charging control current, wherein the frequency of the clock signal is determined in accordance with a frequency of the charge and discharge of the capacitor.