Patent ID: 9541940
Date: 2017-01-10
CPC Classifications: G05F

Claim:
1. An interface supply circuit comprising: a power supply unit; a control unit coupled to the power supply unit; and a detection unit couplable to an interface; wherein the detection unit is configured to: wherein the control unit is configured to be switched on upon receiving the first control signal; and wherein the power supply unit is configured to: be disconnected from the interface in event that the control unit receives the second control signal; wherein the control unit comprises a first control circuit configured to couple to the interface, the power supply unit comprises a first power supply coupled to the first control circuit, the first control circuit is configured to be switched on after receiving the first control signal, the first power supply is configured to supply power to the interface after the first control circuit is switched on, and the first power supply is configured to be disconnected from the interface after the first control circuit receive the second control signal; wherein the first control circuit comprises a first field effect transistor (FET), the first FET comprises a control terminal, a first connecting terminal, and a second connecting terminal, the control terminal of the first FET is coupled to the detection unit, the first connecting terminal of the first FET is configured to couple to the interface, and the second connecting terminal of the first FET is coupled to the first power supply; wherein the first control circuit further comprises a first resistor and a capacitor, one end of the first resistor is coupled to the detection unit, the other end of the first resistor is coupled to the control terminal of the first FET, and the capacitor is coupled between the control terminal of the first FET and the first connecting terminal of the first FET.