USB PERIPHERAL DEVICE DETECTION ON AN UNPOWERED BUS

摘要

A method for detecting connection of a peripheral device for a communication interface of an electronic device and a related detection circuit are provided. The communication interface includes a voltage power line (V_BUS) for feeding power to a peripheral device and a range of nominal operating voltage values relates to a power line. The method includes: a step of applying a nominal voltage included in the range of the nominal operating voltage values to the power line (S4); a step of stopping the nominal operating voltage which are applied to the power line (S1); a step of detecting a transient signal which is generated from the connection of peripheral device for the interface when a residual voltage below the threshold value of the nominal operating voltage exists on the power line (S2); and a step of applying the nominal voltage to the voltage power line according to the detected transient signal.