主权项 |
1. A charging device comprising:
a universal serial bus (USB) port comprising a first data pin, a second data pin, a ground pin, and a power pin; an identification signal providing circuit coupled to the USB port, the identification signal providing circuit configured to output an identification signal to an electronic device that determines whether the charging device is matched to the electronic device or not in response to the electronic device coupled to the USB port; wherein the charging device is configured to charge the electronic device using a first charging current in response to the charging device matched to the electronic device, and the charging device is further configured to charge the electronic device using a second charging current in response to the charging device not matched to the electronic device; the identification signal providing circuit comprises: a first voltage dividing circuit comprising one or more first voltage dividing units; a second voltage dividing circuit comprising one or more second voltage dividing units; a first switch coupled between the first data pin and the first voltage dividing circuit, the first switch controlling the first data pin coupled to one of the first voltage dividing units so that the first voltage dividing circuit supplies a first voltage to the first data pin; and a second switch coupled between the second data pin and the second voltage dividing circuit, the second switch controlling the second data pin coupled to one of the second voltage dividing units so that the second voltage dividing circuit supplies a second voltage to the second data pin; a display unit; and a control unit coupled to the USB port, the first switch, the second switch, and the display unit, the control unit displaying an interface in the display unit to remind a user to select a type of the electronic device from a plurality of predetermined types, and outputting a control signal to the first switch and the second switch according to the type of the electronic device selected by the user. |