Light emitting diode assembly replacement for fluorescent lamp

• US 20080231204A1
• Filed: 03/19/2007
• Published: 09/25/2008
• Est. Priority Date: 03/19/2007
• Status: Abandoned Application

• Current Assignee: Honeywell International Inc.
• Original Assignee: Honeywell International Inc.
• Inventors: Praiswater, Michael R., Wood, Teddy J.
• Application Number:
  US11/725,648
• Publication Number:
  US 20080231204A1
• Time in Patent Office: Days
• US Class Current: 315/192
• CPC Class Codes: H05B 45/357 specially adapted for retrofit LED light sources
• 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 method and apparatus for replacing a fluorescent lighting system with a light emitting diode (LED) system. By connecting the LEDs in accordance with the described embodiment, the fluorescent lamp driving circuit can be reused without modification. The current rating of the LEDs must be equal to or less than the current output of the fluorescent lamp driving circuit. The LED replacement lamp may consist of as few as two LEDs but multiple LEDs may be used as long as the power consumed by the LEDs does not exceed the power rating of the fluorescent lamp driving circuit.

Claims

1. A light emitting diode assembly for use in a fluorescent light circuit, the assembly comprising:

at least one first light emitting diode;

at least one second light emitting diode, wherein an anode of the at least one first light emitting diode is connected to a cathode of at least one second light emitting diode, comprising a first connection and an anode of the at least one second light emitting diode is connected to a cathode of at least one first light emitting diode, comprising a second connection; and

a ballast from the fluorescent circuit affixed to the first connection and the second connection affixed to a power source.

2. The light emitting diode assembly of claim 1 wherein said first light emitting diode comprises a first light emitting diode string and said second light emitting diode comprises a second light emitting diode string.

3. The light emitting diode assembly of claim 2 wherein said first and second light emitting diode strings comprise a plurality of light emitting diodes connected anode to cathode in series.

4. The light emitting diode assembly of claim 1 wherein said at least one first light emitting diode and said at least one second light emitting diode each comprise a predetermined current voltage (IV) characteristic.

5. The light emitting diode assembly of claim 1 wherein said ballast comprises an impedance for limiting a current through said at least one first light emitting diode and said at least one second light emitting diode

6. A light emitting diode assembly for use in a fluorescent light circuit, the assembly comprising:

a first light emitting diode string; and

a second light emitting diode string, wherein the second light emitting diode string is connected in parallel to the first light emitting diode string in opposite polarity.

7. The light emitting diode assembly of claim 6 further comprising a fluorescent light ballast connected to a first junction of the first and second light emitting string and a power source connected to a second junction of the first and second light emitting string.

8. The light emitting diode assembly of claim 7 wherein said ballast comprises an impedance for limiting a current through said at least one first light emitting diode string and said at least one second light emitting diode string.

9. The light emitting diode assembly of claim 6 wherein said first and second light emitting diode strings comprise a plurality of light emitting diodes connected anode to cathode in series.

10. The light emitting diode assembly of claim 6 wherein each light emitting diode from said first light emitting diode string and said second light emitting diode string comprise a predetermined current voltage (IV) characteristic.

11. A method of providing light from light emitting diodes in a fluorescent light circuit, the method comprising the steps of:

providing a first light emitting diode string and a second light emitting diode string, wherein the second light emitting diode string is connected in parallel to the first light emitting diode string in opposite polarity;

affixing a first junction of the first and second light emitting diode strings to a fluorescent circuit ballast and a second junction to a power source; and

energizing the power source.

12. The method of claim 11 wherein the step of energizing comprised conducting a current through the first light emitting diode string during a positive half of the power source and conducting the current through the second light emitting diode string during a negative half of the power source.

13. The method of claim 11 wherein the step of providing comprises selecting a predetermined current voltage (IV) characteristic for each light emitting diode from the first and second light emitting diode strings.