Power management device and method, and electronic device

The present invention provides a power management device and method, and an electronic device. The power management device comprises an output interface, a power converter and an interface controller, wherein the power converter and the interface controller are connected through the output interface, and the power converter is connected with an external power device through the output interface; the power converter is configured to provide output voltage to the output interface; the interface controller is configured to store the work voltage of the external power device in advance, detect the output voltage provided by the power convertor to the output interface, and determines the relation between the output voltage and the work voltage of the external power device, and is configured to control the output interface to break off the connection between the power converter and the external power device when the output voltage is larger than the work voltage of the external power device. According to the technical scheme, the safety of a power device is improved.