LED DRIVER

• US 20140375211A1
• Filed: 06/19/2013
• Published: 12/25/2014
• Est. Priority Date: 06/19/2013
• Status: Abandoned Application

• Current Assignee: Felipe A. Herrador, Monica A. Herrador
• Original Assignee: Felipe A. Herrador, Monica A. Herrador
• Inventors: Herrador, Felipe A., Herrador, Monica A.
• Application Number:
  US13/921,210
• Publication Number:
  US 20140375211A1
• Time in Patent Office: Days
• US Class Current: 315/119
• CPC Class Codes: H05B 45/37 Converter circuits
• CPC Class Codes: Y02B 20/30 Semiconductor lamps, e.g. solid state lamps [SSL] light emitting diodes [LED] or organic LED [OLED]

Abstract

A light emitter diode (LED) driver drives a string of light emitting diodes. A rectifier receives an alternating current (AC) signal across two inputs and produces a direct current (DC) signal across two outputs. The two outputs are connected to ends of the string of light emitting diodes. A first capacitor is connected between a first input of the rectifier and an alternating current source. Current through the string of light emitting diodes is controlled by capacitive reactance of the first capacitor. A second capacitor is connected between the two outputs of the rectifier. A capacitive value of the second capacitor is selected to limit acoustic humming of the LED driver.

Claims

1. A light emitter diode (LED) driver that drives a string of light emitting diodes, the LED driver comprising:

a rectifier that receive an alternating current (AC) signal across two inputs and produces a direct current (DC) signal across two outputs, the two outputs being connected to ends of the string of light emitting diodes;

a first capacitor connected between a first input of the rectifier and an alternating current source, current through the string of light emitting diodes being controlled by capacitive reactance of the first capacitor; and

a second capacitor connected between the two outputs of the rectifier, a capacitive value of the second capacitor being selected to limit acoustic humming of the LED driver.

2. An LED driver as in claim 1 additionally comprising:

a transient voltage suppressor (TVS) diode connected between the two outputs of the rectifier.

3. An LED driver as in claim 1 additionally comprising:

a fuse connected to the alternating current source.

4. An LED driver as in claim 1 additionally comprising:

a transient voltage suppressor (TVS) diode connected between the two outputs of the rectifier; and

,

a fuse connected to the alternating current source.

5. A light emitter diode (LED) light source, comprising:

a string of light emitting diodes; and

an LED driver connected to the string of light emitting diodes, the LED driver comprising;

a rectifier that receive an alternating current (AC) signal across two inputs and produces a direct current (DC) signal across two outputs, the two outputs being connected to ends of the string of light emitting diodes,

a first capacitor connected between a first input of the rectifier and an alternating current source, current through the string of light emitting diodes being controlled by capacitive reactance of the first capacitor, and

a second capacitor connected between the two outputs of the rectifier, a capacitive value of the second capacitor being selected to limit acoustic humming of the LED light source.

6. A light emitter diode (LED) light source as in claim 5, wherein the LED driver additionally comprises:

a transient voltage suppressor (TVS) diode connected between the two outputs of the rectifier.

7. A light emitter diode (LED) light source as in claim 5, wherein the LED driver additionally comprises:

a fuse connected to the alternating current source.

8. A light emitter diode (LED) light source as in claim 5, wherein the LED driver additionally comprises:

a transient voltage suppressor (TVS) diode connected between the two outputs of the rectifier; and

,

a fuse connected to the alternating current source.

9. A method for driving a string of light emitting diodes, the method comprising:

rectifying an alternating current (AC) signal to produces a direct current (DC) signal across two outputs of a light emitting (LED) driver circuit;

controlling current through the string of light emitting diodes by capacitive reactance of a first capacitor; and

limiting acoustic humming of the LED driver circuit by use of a second capacitor connected between the two outputs of the LED driver circuit, wherein capacitive value of the second capacitor is selected to limit the acoustic humming.

10. A method as in claim 9 additionally comprising:

guarding against breakdown reverse current across the string of light emitting diodes by a transient voltage suppressor (TVS) diode connected between the two outputs of the rectifier.

11. A method as in claim 9 additionally comprising:

guarding against shorts by a fuse connected to the alternating current source.

12. A method as in claim 9 additionally comprising:

guarding against breakdown reverse current across the string of light emitting diodes by a transient voltage suppressor (TVS) diode connected between the two outputs of the rectifier; and

,

guarding against shorts by a fuse connected to the alternating current source.