A multiple processor device generates a control packet for at least one connectionless-based packet in partial accordance with a control packet format of the connection-based point-to-point link and partially not in accordance with the control packet format. The apparatus for generating a planar light source comprises an emitting layer disposed not only on a cathode electrode, but also on a gate electrode as well. The switching controller controls onoff of the main switch by using a first voltage corresponding to an output voltage and a first current flowing to the main switch.