Patent ID: 9167650
Filing Date: 2015-10-20
Classification: H05B

Abstract:
1. A light source drive circuit comprising: an LED (Light Emission Diode) portion connected to a first node; a voltage controller connected to the first node and configured to control a voltage of the LED portion; and a current controller connected a second node and configured to control a current of the LED portion and to include: a first transistor connected to the second node and switched according to a PWM (Pulse Width Modulation) signal; a first resistor connected to the second node; a second resistor connected to the first transistor; and a current eliminator configured to eliminate the current flowing through LED portion by discharging a voltage at the first node when the PWM signal is not applied, wherein a first current passing through the LED portion is applied to the second resistor when the first transistor is turned-on, and a second current passing through the LED portion is applied to the first resistor when the first transistor is turned-off.