Patent ID: 7956553

Claim:
A light source driving circuit, for driving a first light-emitting element, the light source driving circuit comprising: a power supply circuit, having an output terminal and a control terminal, wherein the output terminal is connected to a terminal of the first light-emitting element to supply a voltage to the first light-emitting element; a first dimming circuit, having a first terminal, a second terminal, and a pulse width signal input terminal, wherein the first terminal is connected to the other terminal of the first light-emitting element and the second terminal is connected to a common potential; and a control circuit, connected between the pulse width input terminal of the first dimming circuit and the control terminal of the power supply circuit, for receiving and transmitting a pulse width signal to the pulse width signal input terminal of the first dimming circuit and the control terminal of the power supply circuit, such that the first dimming circuit determines an ON/OFF state between the first terminal and the second terminal according to a logic state of the pulse width signal, and the power supply circuit determines whether or not to output the voltage according to the pulse width signal received by the control terminal, and the control circuit delays the power supply circuit to output the voltage according to a first logic state of the pulse width signal, and turns off the power supply circuit to stop supplying the voltage and delays the first dimming circuit to turn off according to a second logic state of the pulse width signal.