The present disclosure relates to a system that utilizes Power over Ethernet (PoE) to supply low voltage direct current (DC) power to a PoE enabled track lighting system. The system facilitates communications with individual track heads located in a PoE enabled low voltage track channel so that the operational characteristics of the individual track heads can be controlled (e.g., dim, brighten, change color), so that feedback on functional status of individual track heads can be obtained, and so that total system current can be regulated. The PoE track lighting system includes a PoE track interface (PTI) device that receives current and communication signals. The PTI device receives the digital communication signals, converts them to a second digital commination signal in a format more suitable for transmission along the communication conductors in the track channel, and transmits the second digital communication signal to the communication conductors of the track channel.

An improved lighting apparatus is disclosed. The lighting apparatus includes a direct current power supply unit, a light emitting unit operating in response to a direct current voltage applied from the direct current power supply unit, and a voltage control unit located between the direct current power supply unit and the light emitting unit to control the level of a voltage applied from the direct current power supply unit to the light emitting unit. The light emitting unit includes first light emitting groups having a first correlated color temperature and being turned on at a first turn-on voltage (V.sub.B) or above and second light emitting groups having a second correlated color temperature and being turned on at a second turn-on voltage (V.sub.A) greater than the first turn-on voltage. The first light emitting groups are connected in parallel with the second light emitting groups. The voltage control unit includes at least one variable resistor to control the level of the voltage applied to the light emitting unit such that the second light emitting groups emit light or are prevented from emitting light, achieving a desired correlated color temperature according to a preset proportion.

A strip of linear lighting with distributed power conversion is disclosed. The linear lighting includes a flexible PCB. The flexible PCB is divided into repeating blocks, which are arranged electrically in parallel with one another between power and ground. Each repeating block includes power conversion and conditioning circuits. A plurality of LED light engines are connected to the outputs of the power conversion and conditioning circuits, electrically in series with one another. The power conversion and conditioning circuits typically include at least a full-bridge rectifier. A pair of conductors run the length of the PCB adjacent to it and are connected to each of the repeating blocks. A flexible, transparent covering surrounds the PCB and pair of conductors.

A lighting apparatus includes: first light emitting elements; second light emitting elements having chromaticity values in a same chromaticity range as the first light emitting elements; and a control circuit including a mode switch for controlling the first light emitting elements and the second light emitting elements separately. The control circuit selectively executes a first mode which causes the first light emitting elements to emit light and a second mode which causes the first light emitting elements and the second light emitting elements to emit light. The mode switch switches between the first mode and the second mode.

A backlight driver chip for an electronic device includes an input that receives data corresponding to a brightness of a backlight device. The backlight driver chip also includes correction circuitry that determines an amplitude correction factor based at least in part on the data and the brightness of the backlight device. The correction circuitry also determines a corrected brightness based at least in part on the amplitude correction factor. The backlight driver chip further includes an output that provides a current signal that drives the backlight device, wherein the current signal is based at least in part on the corrected brightness.

A driver circuit receiving wireless communication over a wireless network is disclosed. The driver circuit includes a lighting load, a main driver, and an auxiliary driver. The lighting load is selectively illuminated based on an output voltage being provided to the lighting load that is at least a forward voltage of the lighting load. The wireless communication is indicative of whether the lighting load is to be illuminated. The main driver is for controlling current and voltage within the driver circuit such that if the wireless communication indicates the lighting load is to be illuminated, then the current delivered to the lighting load is regulated by the main driver, and if the wireless communication indicates the lighting load is not to be illuminated, then the output voltage delivered to the lighting load is controlled by the main driver is below the forward voltage.

A strip of linear lighting with distributed power conversion is disclosed. The linear lighting includes a flexible PCB. The flexible PCB is divided into repeating blocks, which are arranged electrically in parallel with one another between power and ground. Each repeating block includes power conversion and conditioning circuits. A plurality of LED light engines are connected to the outputs of the power conversion and conditioning circuits, electrically in series with one another. The power conversion and conditioning circuits typically include at least a full-bridge rectifier, and a filter may be connected to each of the LED light engines. A pair of conductors run the length of the PCB adjacent to it and are connected to each of the repeating blocks. A flexible, transparent covering surrounds the PCB and pair of conductors.

An LED tube lamp comprises a plurality of LED light sources, an end cap, a power supply disposed in the end cap, a lamp tube, and an LED light strip. The lamp tube extends in a first direction along a length of the lamp tube, and has an end attached to the end cap. LED light strip is electrically connected the LED light sources with the power supply. The LED light strip has in sequence a first wiring layer, a dielectric layer and a second wiring layer. A thickness of the second wiring layer is greater than a thickness of the first wiring layer.

A controller (202) for a horticultural lighting system comprising: a receiver (220) configured to receive a set of lighting parameters; and one or more output terminals configured to provide lighting control signalling to an LED array (210), wherein the lighting control signalling is configured to set one or more operating parameters of the LED array (210) in accordance with the received set of lighting parameters.

A lighting device employs at least one string of LEDs as a lighting source. The string of LEDs is coupled in series with a first switch, wherein the string of LEDs and the first switch are coupled between a power supply node and ground. During a normal operation mode, a system controller is configured to close the first switch to deliver a drive current to the string of LEDs from the power supply node. The system controller is further associated with a temperature sensor and is configured to detect an over-temperature condition based on information provided by the temperature sensor. Upon detecting the over-temperature condition, the system controller will open the first switch to stop the drive current from flowing through the string of LEDs.