LED driving device with feedback control for reducing power consumption

An LED driving device with feedback control for reducing power consumption includes a main power stage circuit, a plurality of current regulators, a detector, and a control unit. The main power stage circuit is provided for supplying a driving voltage to a plurality of LED light strings. An MOSFET element of each current regulator is connected between an output end of an operational amplifier and a current-limiting resistor. The voltage over the current-limiting resistor can be set to be equal to a light dimming signal by the virtual short circuit characteristic of the operational amplifier, such that the light dimming signal is proportional to the current flowing through each LED light string. The detector obtains gate voltages of the MOSFET elements and outputs a maximum gate voltage. The control unit generates a modulation value according to variation of the maximum gate voltage and processes the modulation value to generate a feedback voltage, such that each MOSFET element works at a knee point of the cha