Daisy-chained connected light emitting diode (LED) devices for an automotive direct backlight system are presented herein. Such system can include a group of LED devices communicatively coupled with respective LED devices of the group of LED devices in a daisy-chained manner via serial communication interfaces between the respective LED devices. A host device of the system is directly connected, via a serial peripheral interface, to a foremost device of the respective LED devices, and is communicatively coupled, via the foremost device, to successive devices of the respective LED devices in the daisy-chained manner. The host device synchronizes generation of light by the respective LED devices based on defined timing information, and sends, via the foremost device, respective optical and electrical characteristic data to each of the LED devices to facilitate modification, via LED drivers of the LED devices, of operating characteristics of respective LED chips of the LED devices.

Daisy-chained connected light emitting diode (LED) devices for an automotive direct backlight system are presented herein. Such system can include a group of LED devices communicatively coupled with respective LED devices of the group of LED devices in a daisy-chained manner via serial communication interfaces between the respective LED devices. A host device of the system is directly connected, via a serial peripheral interface, to a foremost device of the respective LED devices, and is communicatively coupled, via the foremost device, to successive devices of the respective LED devices in the daisy-chained manner. The host device synchronizes generation of light by the respective LED devices based on defined timing information, and sends, via the foremost device, respective optical and electrical characteristic data to each of the LED devices to facilitate modification, via LED drivers of the LED devices, of operating characteristics of respective LED chips of the LED devices.

A lighting apparatus includes a rectifier, a 0-10V dimmer converter, a power circuit and a light source. The rectifier for receives an AC power from an AC input to generate a DC current. The TRIAC wall switch is selectively coupled to the AC input. The TRIAC wall switch is operated by a user with an first manual operation to suppress a portion of the AC power from the AC input corresponding to the first manual operation. The 0-10V dimmer converter is selectively coupled to a 0-10V dimmer. The 0-10V dimmer converts a dimmer voltage of the 0-10V dimmer to a dimmer signal corresponding to a second manual operation of the user. The power circuit is coupled to the 0-10V dimmer converter and the rectifier to convert the DC current to a set of driving current. The light source includes multiple LED modules.

A lighting apparatus includes a rectifier, a 0-10V dimmer converter, a power circuit and a light source. The rectifier for receives an AC power from an AC input to generate a DC current. The TRIAC wall switch is selectively coupled to the AC input. The TRIAC wall switch is operated by a user with an first manual operation to suppress a portion of the AC power from the AC input corresponding to the first manual operation. The 0-10V dimmer converter is selectively coupled to a 0-10V dimmer. The 0-10V dimmer converts a dimmer voltage of the 0-10V dimmer to a dimmer signal corresponding to a second manual operation of the user. The power circuit is coupled to the 0-10V dimmer converter and the rectifier to convert the DC current to a set of driving current. The light source includes multiple LED modules.

A method and apparatus for an adaptable vehicle light fixture is provided to activate varying light distribution patterns based upon preconfigured operation of trigger and/or power wires. One or more trigger and/or power wires connected to one or more vehicle light fixtures are preconfigured through wired and/or wireless programming to generate specified light distribution patterns that are responsive to the preconfigurations during manual operation. Wireless preconfiguration includes the use of a handheld magnetic device or smartphone. Wired preconfiguration includes the use of a vehicle-based controller area network (CAN) bus. Any preconfigured operation may be changed at any time by the user by programmably changing the preconfiguration.

An illumination device and method is provided herein for controlling an LED illumination device, so that a desired luminous flux and a desired chromaticity of the device can be maintained over time as the LEDs age. According to one embodiment, the method determines an expected wavelength value and an expected intensity value for each emission LED included within the illumination device at the drive current currently applied to the emission LED and the present emitter forward voltage. In addition, the method determines a photodetector responsivity for each emission LED at the expected wavelength value and the present photodetector forward voltage. The photodetector responsivity calculated for each emission LED is used as a reference for adjusting the lumen output of the emission LED to account for LED aging affects.

A method for estimating a temperature of a light emitting module having a plurality of light emitting elements is provided. The method includes, based on a lighting pattern of the light emitting module, which represents an intensity of light emitted from each of the light emitting elements, estimating respective temperatures of at least a part of the light emitting elements that are operated in accordance with the lighting pattern.

A system includes two or more phosphor-containing white LEDs (or other color-shifting artificial light sources) selected so that their combined color shift over at least 8,000 hours (e.g., at least 10,000 hours, at least 20,000 hours, at least 30,000 hours, at least 40,000 hours, up to 200,000 hours, up to 100,000 hours, up to 80,000 hours) of operation is less than at least one of the LED's (or the other color-shifting artificial light source's) color shift over that time. Here, the combined color shift (Δu′v′) over the at least 8,000 hours (e.g., at least 10,000 hours, at least 20,000 hours, at least 30,000 hours, at least 40,000 hours, up to 200,000 hours, up to 100,000 hours, up to 80,000 hours) of operation can be less than 0.007 (e.g., 0.006 or less, 0.005 or less, 0.004 or less, 0.003 or less, 0.002 or less, 0.001 or less, 0.0005 or less).

A system includes two or more phosphor-containing white LEDs (or other color-shifting artificial light sources) selected so that their combined color shift over at least 8,000 hours (e.g., at least 10,000 hours, at least 20,000 hours, at least 30,000 hours, at least 40,000 hours, up to 200,000 hours, up to 100,000 hours, up to 80,000 hours) of operation is less than at least one of the LED's (or the other color-shifting artificial light source's) color shift over that time. Here, the combined color shift (Δu′v′) over the at least 8,000 hours (e.g., at least 10,000 hours, at least 20,000 hours, at least 30,000 hours, at least 40,000 hours, up to 200,000 hours, up to 100,000 hours, up to 80,000 hours) of operation can be less than 0.007 (e.g., 0.006 or less, 0.005 or less, 0.004 or less, 0.003 or less, 0.002 or less, 0.001 or less, 0.0005 or less).

A voltage-regulating drive circuit for an LED luminaire is disclosed. The drive circuit includes one or several series of LED light engines. A voltage source with a regulator is connected to the series of LED light engines to forward-bias the light engines. The circuit also includes a driver integrated circuit, which may drive the series of LED light engines using, e.g., pulse-width modulation (PWM). The circuit also includes a feedback circuit connected to the cathode end of the series of LED light engines. The feedback circuit receives a remainder voltage and creates a feedback output signal that upregulates or downregulates the regulator of the voltage source to keep a minimum operating voltage on the driver integrated circuit and to compensate for variations in forward voltages among LED light engines in the series.