Battery charger

摘要

A battery charger is provided for implementing a charging method having a stepped output current. The battery charger includes: a power supply circuit that receives an AC input signal and outputs a DC output signal. The power supply circuit (30) includes a power supply controller (55) configured to receive a feedback signal indicative of current being output by the power supply circuit via an amplifier (57) and operates to control current output by the power supply circuit in accordance with the feedback signal. A charger controller (32) is interfaced with the power supply controller to implement a charging method having a stepped output current. The charger controller may set the output current level by adjusting gain of an operational amplifier having a negative feedback configuration with the feedback signal input to a non-inverting input terminal of the operational amplifier, where the charger controller sets the output current level by changing the resistance at an inverting input terminal of the operational amplifier.