Patent ID: 8373363
Filing Date: 2013-02-12
Classification: H05B

Abstract:
1. A method of conditioning current in a light engine, the method comprising: providing a pair of input terminals adapted to receive a periodic excitation voltage; receiving a current of equal magnitude and opposite polarity into each one of the pair of terminals, said current flowing in response to the excitation voltage; providing a plurality of light emitting diodes (LEDs) arranged in a first network, said first network arranged to conduct said current in response to the excitation voltage exceeding at least a forward threshold voltage associated with the first network; providing a plurality of LEDs arranged in a second network in series relationship with said first network; providing a bypass path in parallel with said second network and in series relationship with said first network; dynamically increasing an impedance of the bypass path as a substantially smooth and continuous function of said current amplitude in response to said current amplitude increasing in a range above a threshold current value; permitting said current to flow through said first network and substantially diverting said current away from said second network while a voltage drop across the bypass path is substantially below a forward threshold voltage associated with the second network; and, smoothly and continuously transitioning substantially all of said current from said bypass path to said second network in response to said current increasing in a substantially smooth and continuous manner while the voltage drop across the bypass path exceeds a forward threshold voltage associated with the second network.