Power adapter and control method thereof

A control method, applied to a power adapter, wherein the power adapter includes a power converting circuit, a connecting terminal and a controller, the connecting terminal is configured to connect to an electronic device to allow the power converting circuit to charge the electronic device, the control method comprising:

• receiving an identifying command output from the electronic device;
• determining a charging mode matching the electronic device according to the identifying command;
• outputting a corresponding control signal according to the charging mode to control the power converting circuit to output an output voltage to charge the electronic device;
• determining a type of the electronic device and a charging mode that supported by the electronic device according to identifying commands to adjust the output voltage and an output current correspondingly by the controller;
• and
• determining a battery type of the electronic device according to the identifying command to determine the output current or an upper limit value of the charging voltage by the controller.

A power adapter for charging an electronic device, the power adapter comprising:

• a power converting circuit having an output terminal, and configured to convert an input voltage into an output voltage, and to provide an output current, the power converting circuit outputting the output voltage and the output current through the output terminal;
• a connecting terminal electrically coupled to the power converting circuit to receive the output voltage therefrom, and electrically coupled to the electronic device to transmit the output voltage thereto for charging the electronic device;
• a detection unit electrically coupled to the output terminal of the power converting circuit, and configured to detect the output voltage and the output current, and output a corresponding output voltage detecting signal and a corresponding output current detecting signal;
• and
• a controller electrically coupled to the power converting circuit, the detection unit, and the connecting terminal, and configured to:
• in response to receiving an identifying command from the electronic device, determine a charging mode matching the electronic device according to the identifying command as either a current source output mode or a voltage source output mode;
• when the charging mode of the electronic device is the current source output mode, output the control signal to control the power converting circuit to maintain the output current at a constant current level;
• and
• when the charging mode of the electronic device is the voltage source output mode, output the control signal to control the power converting circuit to increase the output voltage;
• wherein when the charging mode of the electronic device is the current source output mode, the controller is further configured to:
• determine a battery type of a battery of the electronic device and an upper limit value of a charging voltage of the battery of the electronic device according to the identifying command;
• determine when the output voltage of the power converting circuit has reached the upper limit value of the charging voltage from the output voltage detecting signal;
• and
• output the control signal to control the power converting circuit to maintain the output voltage at the upper limit value;
• wherein the electronic device is external to the power converting circuit, the connecting terminal, the detection unit, and the controller of the power adapter and is electrically coupled directly to the connecting unit, and each of the power converting circuit, the controller, and the detection unit is electrically coupled directly to the connecting unit to be electrically coupled to the electronic device via the connecting unit.