US Patent 8432108 Solid state lighting, driver circuits, and related software

LED lighting fixtures, or luminaires, related components, driver circuit, methods, and software/firmware are described that can provide for among other things, ambient environment sensing, thermal self-monitoring, sensor-based power management, communications, and/or programmability. Driver and lighting circuits configured for electrical loads such as series arrangements of light emitting diodes are also described. Embodiments of PFC stages and driver stages can be combined for use as a power supply, and may be configured on a common circuit board. Power factor correction and driver circuits can be combined with one or more lighting elements as a lighting apparatus. Methods of hysteretic power factor correction start-up are also described.