INTERFACE CIRCUIT, PROTECTION METHOD FOR SAME, AND TERMINAL DEVICE

This application is applicable to the field of terminal technologies, and provides an interface circuit, an interface circuit protection method, and a terminal device. The interface circuit includes: a switching unit, a power input end, a first function pin, a second function pin, a control signal input end, a detection port, a grounding output end, a first resistor, a second resistor, a third resistor, a fourth resistor, and an on-off apparatus. Because the first resistor, the second resistor, the third resistor, and the fourth resistor are respectively connected in series as isolation resistors on their respective paths, when a short circuit occurs, a current flowing through the switching unit is less than a burnout current of the switching unit. In addition, when the switching unit does not work, the grounding output end of the switching unit is suspended by using the on-off apparatus, so that the switching unit is in a suspended state when the switching unit does not work, and is not burned down by a voltage that is input during a short circuit, thereby ensuring normal use of the interface.