US Patent 8008864 Single LED string lighting

A solid state lighting unit constituted of: a control circuitry; a single string of light emitting diodes, the single string constituted of a plurality of sections each comprising a plurality of light emitting diodes; and a plurality of bypass paths each responsive to the control circuitry, each of the plurality of bypass paths arranged to provide bypass to a particular one of the plurality of sections, wherein the control circuitry is operative to identify an open circuit condition of a particular one of the plurality of sections, and activate the bypass path arranged to bypass the open circuit section, thereby providing light through sections not exhibiting an open circuit condition.