The disclosure relates to an interface circuit, method and device for state switching and belongs to the terminal technology field. Aspects of the disclosure provide a circuit for switching a device between a master state and a slave state. The circuit includes a first interface configured to couple the circuit with internal circuits of the device, a second interface configured to couple the circuit with a connector structure that is configured to couple the device with another device that is external to the device and control circuits configured to provide a first signal to the internal circuits via the first interface to switch the internal circuits from a first state to a second state, and provide a second signal via the second interface to the other device to switch the other device from the second state to the first state.