Abstract: A lighting system includes a system controller, at least one light fixture, and at least one non-fixture system device. The system controller initiates automated commissioning by instructing a light fixture of the lighting system to modulate light output by the light fixture with a commissioning code. At least one system device of the lighting system receives the modulated light output and demodulates the received light output to determine the commissioning code. In response to determining the commissioning code, the at least one system device sends an acknowledgment message to the system controller. The system controller associates the system devices sending an acknowledgment message with the light fixture providing the light output modulated with the commissioning code.

Abstract: A linear wide area lighting system includes an elongated substrate having a linear light emitter array disposed on the substrate. The array includes a plurality of light emitters such as light emitting diodes or lamps. An elongated refractive lens is positioned over the substrate and linear light emitter array such that light emitted from the emitters is incident on the refractive lens and is refracted through the lens into a wide illumination area. The lens is extruded in some embodiments providing the lens with a substantially uniform extruded cross-sectional profile in some embodiments. The substrate is housed either between a base and the lens in some embodiments, or in an integrally formed bore in the lens body in other embodiments. One or more end caps are located on the longitudinal ends of the lens and base to fully enclose and seal the substrate and linear light emitter array.

Abstract: A driver circuit provides power from a power source to a load. The driver circuit includes a surge protector, an input stage (e.g., full wave rectifier), a controller and an output stage (e.g., a half bridge inverter). The input stage receives power from the power source and provides a direct current (DC) power rail. The controller operates the output stage to provide power from the DC power rail to the load. The controller includes an overvoltage sensing module that shuts down the output stage when the DC power rail exceeds a predetermined voltage. Ceasing operation of the output stage protects the output stage from damage while the DC power rail is above the predetermined voltage.

Abstract: A magnetic component for an electronic circuit includes a core having one or more core surface grooves defined on a side wall, an end wall or both, along the outer core perimeter. Each core surface groove can improve heat flux away from the magnetic component. In some embodiments, a thermally conductive gap filler material is disposed adjacent one or more of the core surface grooves. An electronic device includes a magnetic component with one or more core surface grooves positioned on a circuit board inside an enclosure. The gap filler material spans a gap between the magnetic component and an enclosure wall interior surface, thereby providing a thermal bridge between the component and the enclosure facilitating heat flux away from the core to the enclosure wall.

Abstract: A ballast configured for multiple parallel lamp operation includes a system for detecting unbalanced loads or absent lamps in a parallel multiple lamp ballast. The ballast includes one or more starting transformers having windings, each winding connected in series with a lamp connected to the ballast. A winding of one or more of the starting transformers that is not connected in series with one of the lamps is monitored for a voltage in excess of a threshold. A voltage in excess of the threshold across the winding is indicative of an unbalanced load (e.g., an absent or broken lamp). If a voltage above the threshold is detected across the monitored load, the ballast ceases powering the lamps.

Abstract: An edge-lit lighting apparatus includes a light source and a light guide body. The light guide body includes an input edge, the light source positioned to project light through the input edge in a primary emission direction, the light guide extending from the input edge. The light guide body includes a mean elongation plane which is angularly offset from the primary emission direction. The light guide body includes a reflective side adjacent the input edge and configured to redirect light from the light source. The light guide includes an output side configured to disperse redirected light from the reflected side. The light guide body can extend curvilinearly from the input edge. The lighting apparatus can be configured as an indirect lighting system, and can help increase efficiency for edge-lit lighting systems.

Abstract: A surge protection device provides a dimming control signal to an LED driving system upon failure of surge protection components. Impedance networks are coupled between respective first, second and third input lines for an AC mains. The impedance networks include thermal fuses and metal oxide varistors, with a dimming control circuit having a resistive network coupled between each respective series circuit of fuses and MOV's. The resistive network generates a 0-10V analog dimming signal to an LED device controller, wherein a lighting device operates in full lighting mode while the surge protection device is in normal, high impedance mode, but operates in a dimming mode when one or more of the impedance network devices fail and cause the 0-10V signal to drop below 10 volts. Detection of a dimmed but operable lighting device may serve as warning to an operator that the associated surge protection device component should be replaced.

Abstract: A light emitting apparatus includes a substrate, a light emitter mounted on the substrate, and a lens at least partially covering the light emitter, the lens defining a space about the light emitter. A heat sink is attached to the substrate. The heat sink is configured to dissipate heat from the light emitter via the substrate. The substrate includes an opening communicated with the space. A vent passage is at least partially defined between the heat sink and the substrate, the vent passage communicating the opening in the substrate with an exterior of the heat sink.

Abstract: A power factor correction (PFC) circuit includes an adaptive multiplier feedback control circuit to enhance stability of the PFC circuit for high input voltage and low input power (i.e., low input current) conditions. The adaptive multiplier feedback control circuit controls a voltage provided to a multiplier voltage input of a controller of the PFC circuit. The controller determines control loop gain as a function of the voltage at the multiplier voltage input terminal of the controller. The adaptive multiplier feedback control circuit increases the voltage at the multiplier voltage input of the controller is the input current to the PFC circuit increases. The PFC circuit may be used in an AC to DC converter of the driver circuit of a light fixture operable to provide power to a light source of the light fixture.

Abstract: A lighting apparatus includes a light source. A primary optical surface is configured to receive and redirect light from the light source. A secondary optical surface is configured to receive redirected light from the primary optical surface and further redirect the light in a primary emission direction. The apparatus includes a central opening through the apparatus, the central opening defining a convective path through the apparatus. A thermally conductive cover is placed over the central opening and is positioned in the convective path. The primary optical surface is positioned such that a direct view of the light source is obstructed when the apparatus is viewed from the primary emission direction. The primary and secondary optical surfaces are substantially symmetric about the central opening.

Abstract: A power line communication system communicates dimming levels to a lighting circuit over AC power lines. A power line controller generates control signals which are inserted on the AC power signal to the lighting circuit. A first series resonant circuit is coupled across the AC lines to bypass high frequency components from the control signals. A power line receiver receives the AC power signal and extracts the control signal to generate dimming level signals corresponding with the desired dimming level. To extract the control signal out of the AC power signal, the power line receiver has a resonant circuit connected in parallel with the AC power line and tuned to transmit the ballast control signal and to filter out the AC power signal. A dimming level sensing circuit then senses the signal pattern on the control signal and generates a dimming level signal corresponding to the desired dimming level.

Abstract: A high power factor DC power supply with low output ripple uses a variable gain DC to DC converter and fast averaging control loop to eliminate the need for a large electrolytic capacitor at the output of the PFC circuit. A resonant tank circuit of the DC to DC converter is sized to provide a predetermined output voltage to the load when the PFC circuit output is at its minimum. A closed loop control circuit varies an operational frequency of the DC to DC converter (i.e., an inverter of the DC to DC converter driving the resonant tank circuit) to compensate for voltage ripple on the DC power rail provided to the DC to DC converter from the PFC circuit. An optional clamping circuit limits output from the resonant tank to the load to further reduce ripple in the power provided to the load.

Abstract: A bobbin apparatus for a magnetic component includes a core passage having one or more core passage steps located therein. The core passage steps provide one or more gaps between a core disposed in the core passage and the bobbin body. A potting material may be disposed in the gap or gaps in some applications to enhance heat transfer and/or to improve magnetic component performance by reducing effects of fringing flux on inner windings. A method of assembling a magnetic component to include one or more gaps between the core and bobbin core passage is also provided.

Abstract: An auxiliary winding circuit board includes one or more auxiliary conductive windings. The auxiliary winding circuit board is positioned at an axial end of a bobbin, and a core leg extends through an opening in the auxiliary winding circuit board. A main conductive winding is positioned on the bobbin. The auxiliary winding disposed on the auxiliary printed circuit board has enhanced voltage-isolation from the main winding positioned on the bobbin, allowing both a high-voltage main winding and a low-voltage auxiliary winding to be located on one magnetic component. The magnetic component is configured for mounting on a printed circuit board for an electronic device such as a power supply. A modular magnetic component apparatus includes a bobbin with main winding assembly and multiple auxiliary winding circuit boards that may be interchangeably mounted between the bobbin and core for desired applications.

Abstract: A light fixture includes a surge protection circuit for a non-isolated DC-DC converter. The converter is coupled to a circuit ground and further provides output power to a light source chassis configured to house a light source. The chassis is coupled to earth ground. The surge protection circuit includes a voltage triggering device having a breakdown voltage value and coupled to either the circuit ground or an output of the converter. A first capacitor is coupled in series between the voltage triggering device and the earth ground, and a second capacitor is coupled in parallel with the voltage triggering device. The first capacitor is configured with a sufficiently large capacitance wherein a voltage across the first capacitor, and likewise a voltage between the chassis and the earth ground, is effectively clamped to a light source threshold value during a surge condition.

Abstract: An LED driver circuit includes circuitry for indirect sensing of an isolated output current. A rectifier circuit produces DC power to a power factor correction circuit including a switch and a primary transformer winding. An LED array is coupled to a secondary winding of the transformer. An auxiliary transformer winding is coupled to a feedback circuit which generates a feedback signal that is representative of the output current without receiving any direct feedback from the secondary side of the transformer. A capacitor may be coupled across the auxiliary winding, which charges and discharges energy as the switch is driven on and off. A controller further drives the switch based on comparison of an average voltage across the capacitor with respect to a reference value corresponding to desired output current through the load. The reference value may be provided to the controller from an external dimming control circuit.

Abstract: A high power factor, constant current, buck-boost LED driver circuit is provided with floating IC driving control. A DC power supply is provided with a first input and a second input that is coupled to a mains ground. A switching circuit is coupled to receive the first input and to convert input power into a constant current supply for an LED load. A current sensor is coupled to the switching circuit and configured to provide feedback signals representative of a current through the LED load, and a controller is coupled to the switching circuit and the current sensor and configured to provide driver signals to the switching circuit based at least in part on the feedback signal. Each of the switching circuit, the current sensor and the controller are commonly coupled to a floating circuit ground. A buck-boost inductor is further coupled between the floating ground and mains circuit ground.

Abstract: A magnetic component apparatus includes a bobbin having a bobbin body, a first pin rail, a second pin rail, and a longitudinal axis. First and second pin rows are located on the first pin rail. The second pin row is located at an exterior position from the first pin row. A third pin row is located on the second pin rail. The first, second, and third pin rows can be oriented in a direction transverse to the longitudinal axis. A plurality of windings can be located on the bobbin body. Some embodiments can include a fourth pin row located on the second pin rail, the fourth pin row located at an exterior position from the third pin row. In some embodiments one or more wire guide channels can be defined in the first or second pin rails to help keep breakout wires from the plurality of windings separate.

Abstract: A constant current source has an increased differential amplifier gain at low output currents and a decreased differential amplifier gain at high output currents. The differential amplifier amplifies a sensed output current of the constant current source. A gain control circuit scales a reference current in conjunction with the gain applied to the sensed output current to maintain stable operation of the constant current source. The constant current source may be used in a driver circuit to provide power to a light source (e.g., an LED light).

Abstract: A high efficiency electronic ballast or driver circuit provides striation control at reduced power levels. The driver circuit includes a controller operating a half-bridge inverter to drive a resonant tank circuit. The controller provides asymmetric on-times to upper and lower switches of the half-bridge inverter when operating at low duty cycles (e.g., duty cycles of 50% or less). The resulting asymmetric output current eliminates striation in lamps driven by the ballast. In order to maintain light output (i.e., output current), the controller reduces the operating frequency of the half-bridge inverter to increase the gain and impedance of the resonant tank circuit.