Power supply apparatus and electric apparatus having the same

The power supply is disclosed. The apparatus of the first events is required for the switching unit, and a group reference voltage below the set which is disposed between the pluralities of the plurality of power supply, are arranged as a single array, the power supply control the connection of the plurality of power supply voltage When the generated parallel connection of each of the plurality of power supply, and the group if the second event, which is the required voltage exceeding the predetermined reference voltage and generate a control unit for controlling the switching unit to each of the plurality of power supply to the serial connection.