A control device for current switching, comprising: a USB OTG interface which is configured to connect to a first device and has a low level at an ID pin; a USB interface which is configured to connect to a second device and has a high level at an ID pin; a booster current-limiting circuit connected between the USB OTG interface and the USB interface, wherein the booster current-limiting circuit, the USB OTG interface, and the USB interface form a line for the first device to supply power to the second device; a measuring and controlling unit connected to the booster current-limiting circuit, a physical key connected to the measuring and controlling unit, wherein the measuring and controlling unit is configured to change, in a case that a current switching request is received from the physical key, a resistance value of a current-limiting circuit in the booster current-limiting circuit, so that the first device supplies a corresponding current to the second device, and wherein the physical key is configured to generate, after being pressed, the request for the first device to supply the corresponding current to the second device, wherein the measuring and controlling unit is configured for detecting how many times the physical key is pressed within a preset duration, wherein the measuring and controlling unit is configured for controlling the resistance value of the current-limiting circuit in the booster current-limiting circuit, so that - the first device supplies a first current to the second device, if the measuring and controlling unit detects that the number of times the physical key has been pressed is one, - the first device supplies a second current to the second device, if the measuring and controlling unit detects that the number of times the physical key has been pressed is two. a USB OTG interface which is configured to connect to a first device and has a low level at an ID pin; a USB interface which is configured to connect to a second device and has a high level at an ID pin; a booster current-limiting circuit connected between the USB OTG interface and the USB interface, wherein the booster current-limiting circuit, the USB OTG interface, and the USB interface form a line for the first device to supply power to the second device; a measuring and controlling unit connected to the booster current-limiting circuit, a physical key connected to the measuring and controlling unit, wherein the measuring and controlling unit is configured to change, in a case that a current switching request is received from the physical key, a resistance value of a current-limiting circuit in the booster current-limiting circuit, so that the first device supplies a corresponding current to the second device, and wherein the physical key is configured to generate, after being pressed, the request for the first device to supply the corresponding current to the second device, wherein the measuring and controlling unit is configured for detecting how many times the physical key is pressed within a preset duration, wherein the measuring and controlling unit is configured for controlling the resistance value of the current-limiting circuit in the booster current-limiting circuit, so that - the first device supplies a first current to the second device, if the measuring and controlling unit detects that the number of times the physical key has been pressed is one, - the first device supplies a second current to the second device, if the measuring and controlling unit detects that the number of times the physical key has been pressed is two. - the first device supplies a first current to the second device, if the measuring and controlling unit detects that the number of times the physical key has been pressed is one, - the first device supplies a second current to the second device, if the measuring and controlling unit detects that the number of times the physical key has been pressed is two.