Abstract: The present invention is a driving circuit for a flat display. The flat display comprises a panel and at least two light tubes as a backlight source of the panel. The driving circuit comprises two transformers. Each transformer has a primary side and a secondary side. The primary sides of the two transformers are connected to a resonance circuit. The secondary side of each transformer is connected to a corresponding light tube for illumination. The windings on the primary sides of the two transformers are the same, and the windings on the secondary sides of the two transformers are different from each other by reversing the winding on the secondary side of one of the two transformers.