LED driving circuit

• US 8,975,833 B2
• Filed: 10/16/2012
• Issued: 03/10/2015
• Est. Priority Date: 10/17/2011
• Status: Active Grant

• Current Assignee: LG Innotek Company Limited (LG Corporation)
• Original Assignee: LG Innotek Company Limited (LG Corporation)
• Inventors: Han, Jae Hyun
• Primary Examiner(s): CRAWFORD, JASON
• Application Number:
  US13/652,769
• Publication Number:
  US 20130093355A1
• Time in Patent Office: 875 Days
• Field of Search: 315/291, 315294-295, 315/297
• US Class Current: 315/294
• CPC Class Codes: H05B 45/14 using electrical feedback from LEDs or from LED modules
• CPC Class Codes: H05B 45/38 using boost topology
• CPC Class Codes: Y02B 20/30 Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]

Abstract

Disclosed is an LED driving circuit. The LED driving circuit includes a power supply, an LED array to receive a signal of the power supply, an IC connected to the LED array, and an inrush current restricting part to gradually increase an output current recognized in the IC. The inrush current restricting part comprises at least one of a frequency adjusting part and a current adjusting part.

Claims

1. An LED driving circuit comprising:

a power supply;

an LED array to receive a signal of the power supply;

an IC connected to the LED array; and

an inrush current restricting part to gradually increase an output current recognized in the IC,

wherein the inrush current restricting part comprises at least one of a frequency adjusting part and a current adjusting part,

wherein the frequency adjusting part comprises an FET, a capacitor, and a resistor, and wherein one end of the resistor is connected to a ground terminal, and an opposite end of the resistor is connected to a gate of the FET, and

wherein the current adjusting part comprises an FET, a capacitor, and a resistor, and wherein one end of the capacitor is connected to a ground terminal, and an opposite end of the capacitor is connected to a gate of the FET.

2. The LED driving circuit of claim 1, wherein the FET is an N type FET.

3. The LED driving circuit of claim 2, further comprising a resistor connected to a drain of the N type FET.

4. The LED driving circuit of claim 1, wherein the FET is an N type FET.

5. The LED driving circuit of claim 4, further comprising a resistor connected to a drain of the N type FET.

6. An LED driving circuit comprising:

a power supply;

an LED array to receive a signal of the power supply;

an IC connected to the LED array; and

an inrush current restricting part to gradually increase an output current recognized in the IC,

wherein the inrush current restricting part comprises a frequency adjusting part and a current adjusting part, and

wherein the frequency adjusting part is connected to the current adjusting part in parallel.

7. The LED driving circuit of claim 6, wherein the frequency adjusting part and the current adjusting part receive a voltage which is output through voltage division by voltage division resistors.

8. The LED driving circuit of claim 7, wherein the voltage, which is output through the voltage division by the voltage division resistors, is input to the current adjusting part through a fourth resistor connected in series, and input to the frequency adjusting part through a first capacitor connected in series.

9. An LED driving circuit comprising:

a power supply;

an LED array to receive a signal of the power supply;

an IC connected to the LED array; and

an inrush current restricting part to gradually increase an output current recognized in the IC,

wherein the inrush current restricting part comprises a frequency adjusting part and a current adjusting part, the frequency adjusting part comprises a P type FET, the current adjusting part comprises an N type FET, and a voltage applied to a gate terminal of the P type FET is equal to a voltage applied to a gate terminal of the N type FET.

10. The LED driving circuit of claim 9, wherein the current adjusting part comprises an FET, a capacitor, and a resistor, and wherein one end of the capacitor is connected to a ground terminal, and an opposite end of the capacitor is connected to the gate terminal of the FET.