SHUNT REGULATOR FOR SPECTRAL SHIFT CONTROLLED LIGHT SOURCE

• US 20160212817A1
• Filed: 01/25/2016
• Published: 07/21/2016
• Est. Priority Date: 02/11/2014
• Status: Active Grant

• Current Assignee: Signify North America Corporation (Signify N.V.)
• Original Assignee: Once Innovations Inc. (Signify N.V.)
• Inventors: Grajcar, Zdenko, Erickson, Leif
• Granted Patent: US 10,091,857 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: A01K 45/00 Other aviculture appliances, e.g. devices for determining whether a bird is about to lay
• CPC Class Codes: H05B 45/10 Controlling the intensity of the light
• CPC Class Codes: H05B 45/24 using electrical feedback from LEDs or from LED modules
• CPC Class Codes: H05B 45/397 Current mirror circuits
• CPC Class Codes: H05B 45/46 having LEDs disposed in parallel lines
• CPC Class Codes: H05B 45/48 having LEDs organised in strings and incorporating parallel shunting devices
• 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 emitting diode lighting assembly that receives an electrical excitation signal that is varied from a dimming device. Driving circuitry receives the varying input and has first and second paths that each have a plurality of light emitting diodes. Each plurality of light emitting diodes has a threshold voltage with the threshold voltage of the first plurality of diodes being less than the threshold voltage of the second plurality of lighting emitting diodes. The current within the first path is controlled by a current limiting device that is controlled by a resistor that receives input from the second path to gradually turn off the first plurality of light emitting diodes as the second plurality of lighting emitting diodes increase in intensity. A shunt voltage regulator within the circuit having a threshold voltage that is above threshold voltages of components in the assembly to minimize voltage increases in the assembly.

Claims

1. A light emitting diode lighting assembly comprising:

driving circuitry adapted to receive an electrical excitation signal from a DC input varied in intensity by a dimming device that actuates to increase and decrease voltage of the electrical excitation signal;

said driving circuitry comprising a first plurality of light emitting diodes in a first path in parallel relation to a second plurality of light emitting diodes in a second path;

said first plurality of light emitting diodes having a first threshold voltage, and said second plurality of light emitting diodes having a second threshold voltage greater than the first threshold value;

a current limiting device within the first path to limit current within the first path;

a resistor in series relation with the current limiting device and the second plurality of light emitting diodes;

wherein as voltage increases above the second threshold voltage the resistor actuates the current limiting device to prevent flow of current to the first plurality of light emitting diodes;

a voltage regulator in parallel with the resistor and having a threshold voltage greater than the second threshold voltage to prevent a voltage increase in the assembly above the threshold voltage of the voltage regulator.