US Patent 8179055 LED circuits and assemblies

An AC-driven LED circuit 10 includes a first parallel circuit 12 having a first branch 14 and a second branch 16 which connect at first and second common point 18, 20. The common points 18, 20 provide input and output for an AC driving current from a driver of the circuit. The first branch 14 has a first LED 26 and a second LED 28, the first LED 26 being connected to the second LED 28 in opposing series relationship with the inputs of the first and second LEDs 26, 28 defining a first branch junction 34. A second branch 16 has a third LED 30 and a fourth LED 32, the third LED 30 is connected to the fourth LED 32 in opposing series relationship with the outputs of the third and fourth LEDs 30, 32 defining a second branch junction 36. Improvement in performance and scalability is provided by adding n diodes to a given parallel circuit and x cross connecting circuit branch diodes (40, 44) and providing one or more parallel circuits (15) in series and or parallel. An AC-driven LED assembly with discretely packaged LEDs being connected in an AC circuit and being sized preferably substantially 2.5 mm or less in length and width, and more preferably 2.0 mm or less; and being mounted to a substrate at a distance from the other of preferably approximately 3 mm or less, and more preferably 2.0 mm or less.