USB EXPANDING DEVICE

The disclosure provides a USB expanding device comprising a plurality of USB type-C connection units, a transmission controller, and a main controller. Each of a USB type-C connection unit includes a USB type-C port, a multiplexer, and a power transmission controller. The USB type-C port provides for connecting to an external device. The multiplexer connects to the USB type-C port and the power transmission controller. The transmission controller connects to the multiplexers of each of the USB type-C connection units for controlling the transmission of data, and the main controller connects to the power transmission controllers of each of the USB type-C connection units to distribute power according to the charging request information of the power transmission controllers.