Patent ID: 7573205

Claim:
A lamp-lighting apparatus comprising: an inverter transformer having primary and secondary windings; a switching circuit connected with the primary winding of said inverter transformer and converting a voltage from an input power supply by switching; a balancer connected with the secondary winding of said inverter transformer and acting to make uniform electrical currents flowing through plural lamps, respectively, wherein said balancer is provided for each of said lamps, and further comprising a first detection circuit for detecting a voltage corresponding to a voltage generated at the secondary winding of said inverter transformer, a second detection circuit for detecting a voltage corresponding to a maximum one of voltages generated at which said balancer are assigned to said lamps, respectively, and a circuit for summing up an output voltage from said first detection circuit and an output voltage from said second detection circuit; and a control circuit for producing a control signal for controlling the switching performed by said switching circuit based on a voltage corresponding to the sum of a voltage generated at the secondary winding of said inverter transformer and a voltage generated at said balancer.