Abstract: Disclosed is a light emitting diode (LED)-based lighting fixture including an LED and a voltage supply configured to provide electrical power to the LED. The LED-based lighting fixture also includes a temperature sensor configured to determine a temperature at a selected location of the lighting fixture; and a controller connected between the temperature sensor and the voltage supply and configured to determine an ambient temperature and a drive current based on the ambient temperature and to provide an input voltage to the LED based on the drive current. A method of controlling the operational lifetime of an LED, a computer readable medium and an apparatus are also described.

Abstract: A method for providing universal voltage input to a solid state lighting fixture (140) supplied by an AC line voltage includes converting an analog voltage signal corresponding to the line voltage to digital values indicating a waveform of the line voltage (S312) and calculating slopes corresponding to rising edges of the waveform using select values of the digital values (S453). A value of the line voltage is determined based on the calculated slopes (S458).

Abstract: A method for providing universal voltage input to a solid state lighting fixture (140) supplied by an AC line voltage includes converting an analog voltage signal corresponding to the line voltage to digital values indicating a waveform of the line voltage (S312) and calculating slopes corresponding to rising edges of the waveform using select values of the digital values (S453). A value of the line voltage is determined based on the calculated slopes (S458).

Abstract: Disclosed is a light emitting diode (LED)-based lighting fixture including an LED and a voltage supply configured to provide electrical power to the LED. The LED-based lighting fixture also includes a temperature sensor configured to determine a temperature at a selected location of the lighting fixture; and a controller connected between the temperature sensor and the voltage supply and configured to determine an ambient temperature and a drive current based on the ambient temperature and to provide an input voltage to the LED based on the drive current. A method of controlling the operational lifetime of an LED, a computer readable medium and an apparatus are also described.

Abstract: A lighting fixture, and methods for powering and operating same. The fixture comprises a housing having multiple portions. One or more power and control circuit boards are disposed in a first portion of the housing, comprising one or more switching power supplies for receiving an A.C. line voltage and providing a D.C. output voltage, and a communication protocol converter for receiving first lighting instructions formatted according to a first communication protocol and converting at least some of the first lighting instructions to second lighting instructions formatted according to a second communication protocol. A plurality of modular circuit boards are disposed in the second portion of the housing and coupled to the power and control circuit board(s). Each modular circuit board comprises a plurality of LED-based lighting units coupled to the D.C. output voltage and responsive to the second lighting instructions formatted according to the second communication protocol.

Abstract: LED-based lighting fixtures suitable for general illumination in surface-mount or suspended installations, in which heat dissipation properties of the fixtures are significantly improved by decreasing thermal resistance between LED junctions and the ambient air. In various examples, improved heat dissipation is accomplished by increasing a surface area of one or more heat-dissipating elements proximate a trajectory of air flow through the fixture. In one aspect, various structural components of the fixtures are particularly configured to create and maintain a “chimney effect” within the fixture, resulting in a high air-flow rate, natural convection cooling system capable of efficiently dissipating the waste heat from the fixture without active cooling.

Abstract: Methods and apparatus for high power factor power transfer to a load using a single switching stage. In exemplary implementations, a controllable variable power may be delivered to a load using a single switching stage while maintaining high power factor, in some cases without requiring any feedback information relating to the load conditions (i.e., without monitoring load voltage and/or current) to control normal switching operations in the single switching stage, and without requiring regulation of load voltage and/or load current. In one example, a single stage high power factor driver is used to control power delivery to an LED-based light source.

Abstract: LED-based lighting fixtures suitable for general illumination in surface-mount or suspended installations, in which heat dissipation properties of the fixtures are significantly improved by decreasing thermal resistance between LED junctions and the ambient air. In various examples, improved heat dissipation is accomplished by increasing a surface area of one or more heat-dissipating elements proximate a trajectory of air flow through the fixture. In one aspect, various structural components of the fixtures are particularly configured to create and maintain a “chimney effect” within the fixture, resulting in a high air-flow rate, natural convection cooling system capable of efficiently dissipating the waste heat from the fixture without active cooling.

Abstract: Power control methods and apparatus in which a switching power supply provides power factor correction and an output voltage to a load via control of a single switch, without requiring any feedback information associated with the load. The single switch may be controlled without monitoring either the output voltage across the load or a current drawn by the load, and/or without regulating either the output voltage across the load or the current drawn by the load. The RMS value of an A.C. input voltage to the switching power supply may be varied via a conventional A.C. dimmer (e.g., using either a voltage amplitude or duty cycle control technique) to in turn control the output voltage. The switching power supply may comprise a flyback converter configuration, a buck converter configuration, or a boost converter configuration, and the load may comprise an LED-based light source.

Abstract: A lighting fixture, and methods for powering and operating same. The fixture comprises a housing having multiple portions. One or more power and control circuit boards are disposed in a first portion of the housing, comprising one or more switching power supplies for receiving an A.C. line voltage and providing a D.C. output voltage, and a communication protocol converter for receiving first lighting instructions formatted according to a first communication protocol and converting at least some of the first lighting instructions to second lighting instructions formatted according to a second communication protocol. A plurality of modular circuit boards are disposed in the second portion of the housing and coupled to the power and control circuit board(s). Each modular circuit board comprises a plurality of LED-based lighting units coupled to the D.C. output voltage and responsive to the second lighting instructions formatted according to the second communication protocol.

Abstract: Methods and apparatus for high power factor power transfer to a load using a single switching stage. In exemplary implementations, a controllable variable power may be delivered to a load using a single switching stage while maintaining high power factor, in some cases without requiring any feedback information relating to the load conditions (i.e., without monitoring load voltage and/or current) to control normal switching operations in the single switching stage, and without requiring regulation of load voltage and/or load current. In one example, a single stage high power factor driver is used to control power delivery to an LED-based light source.