Patent ID: 7847493

Claim:
A lamp driving apparatus for use with a backlight module having a plurality of lamps, each lamp comprising at least a high-voltage end, the lamp driving apparatus comprising: an inverter to output driving voltages to the corresponding lamps; and a feedback circuit connected to the high-voltage ends of the lamps to detect lamp currents of respective lamps, and to provide a feedback indication accordingly, wherein the inverter is configured to adjust the driving voltages according to the feedback indication, wherein the feedback circuit comprises: a plurality of current detection devices, each of the current detection devices connected to the high-voltage end of the corresponding lamp to receive the corresponding lamp current and to output a respective current signal according to the lamp current, wherein the current detection devices comprise devices selected from current transformers and optical couplers; and a plurality of diodes, each of the diodes comprising an anode and a cathode, the anodes for respectively receiving the current signals, and the cathodes connected to each other for providing the feedback indication.