Power management device of an electronic card

A power management device of electronic card comprising;

• a functional module providing functions of a specific electronic card;
• an interface bus adapted to be connected to a host, wherein the host provides an interface power through the interface bus;
• a bus bridge unit connected between the functional module and the interface bus for converting interface formats therebetween;
• a power storage unit for supplying a storage power to the functional module;
• an external power input unit adapted to be inserted into an external power plug for selectively providing an external power to the functional module and charging the power storage unit;
• and
• a power control unit for controlling the bus bridge unit, the external power input unit, the power storage unit and the power control unit so as to selectively supply the interface power from the bus interface unit to the functional module and further charge the power storage unit, directly supply the interface power from the bus interface unit to the power storage unit for charging the same, supply the external power from the external power input unit to the functional module and further charge the power storage unit, and directly supply the external power from the external power input unit to the power storage unit for charging the same.