Patent ID: 8080945

Claim:
A multiple lamp driving device, comprising: a power supply unit for supplying a driving voltage to a lamp unit provided with first to 4n th lamps; and a balancing circuit unit including first to n th balance transformers for receiving the driving voltage from the power supply unit and for balancing currents flowing through the first to 4n th lamp, wherein each of the first to nth balance transformers includes: a primary side connected to the power supply unit in series; first and second secondary sides coupled with the primary side; capacitors positioned at both ends of the corresponding balance transformer, without being electrically connected to the primary side or the first and second secondary sides, in order to protect the first to 4n th lamps in an erroneous operation; and first sensing resistors positioned between the capacitors and the ground, the first sensing resistors being configured to allow currents from the capacitors to flow into the ground through the first sensing resistors, wherein one end of each of the first and second secondary sides is connected to one end of one of the first to 4n th lamps, the other end of each of the first and second secondary sides is connected to one end of another among the first to 4n th lamps, and the other ends of all of the first to 4n th lamps are connected to a ground.