Abstract: Disclosed is a strip lighting system that receives lighting control signals digitally over a conductor which also provides power to the strip lighting system. The strip lighting system includes a controller which receives the control signals operates switches which cause current to flow through one or more light emitting diodes and also a non-lighting load to permit the strip lighting system to have a constant load characteristic to a lighting system controller controlling the strip lighting system.

Abstract: Provided in this disclosure is a control system and method that monitors current in a spreader motor to accurately detect a mechanical overload condition. The invention distinguishes between a short duration high current transient spike caused by sparking of brushes in the DC motor, and a long duration continuous high current caused by a mechanical overload condition in the DC motor. The control system momentarily deactivates and reactivates the motor. If high current is no longer detected, the control system construes this as a transient spike and no fault condition is indicated. If high current persists, the control system construes this as an actual overload condition, and a fault condition is indicated to the operator. In this manner, a selected default current level can be established in the control system which can be selectively reestablished if conditions within the device change over time.

Abstract: A light-emitting diode (LED) light string control system using carrier signal control includes a control module and an LED light string coupled to the control module. The control module converts a DC voltage into a lighting drive signal according to a lighting command. The LED light string includes at least one LED module, and the at least one LED module includes a detection circuit, a logic circuit, and an oscillator. The detection circuit generates a detected signal corresponding to the lighting drive signal. The logic circuit determines a first level being a first logic signal, a second logic signal, or a latch signal according to a time duration of the detected signal at the first level. The oscillator provides a clock signal to the logic circuit for calculating the time duration according to the first level.

Abstract: Provided is a buck-boost converting circuit including an LED current regulator and bypass switches. The buck-boost converting circuit includes switches coupled in a matrix form in order to individually control a plurality of LEDs connected in series, an LED current regulator, and a circuit capable of buck-boost conversion.

Abstract: The present disclosure relates to the field of display technology, and provides driving methods of a display panel and a display device.

Abstract: An intrinsically safe (IS) luminaire disposed in a hazardous environment provides visible light and serves as a primary, auxiliary, back-up, and/or charging source of IS DC power for external devices disposed in the hazardous environment, such as process control devices and equipment. The luminaire includes a power converter that converts received power into DC power, an IS barrier that converts the DC power into IS DC power native to or utilized by a recipient external device, and a power distribution port via which IS DC power is delivered to the external device. In some configurations, the luminaire monitors communicates statuses, alerts, and/or other information corresponding to delivering IS DC power to one or more external devices to a host and/or portable communication device. The luminaire may include multiple IS barriers of same and/or different IS ratings, and may dynamically control activation/deactivation of the IS barriers and/or usages thereof.

Abstract: A lighting fixture for a Light Emitting Diode, LED, lighting device, said fixture comprising an LED driver arranged to receive an Alternating Current, AC, mains voltage as input and provide an LED current to drive said LED lighting device; at least one socket comprising receiving means, arranged to receive and hold an LED lamp arranged to emit light, said socket further comprising a biased Double Pole Double Throw, DPDT, switch, comprising one set of input terminals and two sets of output terminals, wherein the output of said LED driver is connected to said input terminals of said biased DPDT switch, wherein a first of said two output terminals of said biased DPDT switch are short circuited, and wherein said biased DPDT switch is arranged to toggle between a short circuit position wherein said input terminals of said biased DPDT switch are connected to said first set of output terminals, and a connected position wherein said input terminals of said biased DPDT switch are connected to a second of said two outp

Abstract: A boost converter for improving output stability includes a transformer, a detection circuit, a first resistor, a power switch element, an output stage circuit, a feedback compensation circuit, a controller, an inverter, and a multiplier. The transformer includes a main coil and a secondary coil. The main coil receives an input voltage. The detection circuit is coupled to the secondary coil. The detection circuit generates a detection voltage. The first resistor is coupled to the main coil. The output stage circuit generates an output voltage. The feedback compensation circuit generates a feedback voltage according to the output voltage. The inverter generates an inverted oscillation voltage. The multiplier generates a compensation voltage difference according to the detection voltage, the inverted oscillation voltage, and the feedback voltage. The compensation voltage difference is applied to the first resistor.

Abstract: A LED lighting circuit has a plurality of LED segments connected in series. A switching arrangement is used to selectively bypass at least one LED segment to implement a tapped linear driver approach. Degrading of a component in the LED lighting circuit is detected, so that a first TLD current modulation scheme is implemented when no such degrading is detected whereas a second current modulation scheme, different from the first current modulation scheme, is implemented to compensate for said degrading. Said degrading is leading to an increase in a turning on voltage of one LED segment, and compared to said first current modulation scheme, said second current modulation scheme has a higher voltage threshold at which said LED segment is switched. In this way, protection may be provided for circuit components and the light output may be maintained at the desired level in the event of component degrading, such as LED chip failure or contact resistance changes.

Abstract: AC-driven light-emitting diode systems and methods are provided for driving LED devices (e.g., LED lighting) using AC power. For example, an integrated circuit includes a first power line and a second power line configured for connection to AC power, and a plurality of LED stages, wherein each LED stage comprises multiple serially-connected LED devices, switches connected to inputs and outputs of the LED stages. The integrated circuit further includes switch control circuitry configured to control the switches to selectively connect one or more of the LED stages to the first and second power lines to empower the LED stages with the AC power.

Abstract: According to at least one aspect, a lighting system is provided. The lighting system comprises a strip lighting device including a circuit board, a light emitting diode (LED) mounted to the circuit board, a lens disposed over the LED and configured to receive the light emitted from the LED and change at least one characteristic of the light received from the LED, and an elastomer encapsulating at least part of the circuit board. The lighting system further comprises a fixture configured to receive the strip lighting device and mount to a structure and a lighting accessory configured to removably couple to the fixture over the strip lighting device and change at least one characteristic of the light from the strip lighting device.

Abstract: The present invention provides a circuit for linearly driving LED illumination based on MCU-controlled color temperature switching, comprising an SCM color temperature control module, an LED linear dimming driving and control module and an LED illumination module. The SCM color temperature control module may output two PWM signals, to adjust the ratio of current at the LED bead strings, thus to synthesize two or more different color temperatures. Or, the SCM color temperature control module outputs multi-channel control signals and then controls a color temperature output module to control the ratio of current at the LED bead strings at high and low color temperatures, thus to realize two or more color temperatures. Furthermore, a memory function or a non-memory function can be realized, if desired. The LED linear dimming driving and control module can control and adjust the illuminance of the LED illumination module, and can realize a dimming function.

Abstract: An LED lighting apparatus capable of color temperature control includes a color temperature controller to receive a color temperature selection signal and output first and second control signals; a LED driver connected a plurality of LED groups; and a LED selection circuit including a first switch connected to a first node to which a rectified voltage is applied and receiving the first control signal, a first LED group selectively connected to the first node by the first switch, a second LED group connected in scales with the first LED group, a third LED group selectively connected to the first node by the first switch, a fourth LED group connected in series with the third LED group, and a second switch for selectively connecting the output terminal of the second LED group or the fourth LED group to the LED driver by receiving the second control signal.

Abstract: A display device comprises a control circuit and a plurality of LED channels coupled to a shared supply voltage. The control circuit obtains respective brightness levels for each of the LED channels and determines, based on the brightness levels, a group current level sufficient to drive all of the LED channels. The control circuit also determines respective duty cycles for each of the LED channels that will achieve the respective brightness levels when each of the LED channels are driven with the group current level. The control circuit configures driver circuits to drive the LED channels in accordance with the group current level and the respective duty cycles. The control circuit may furthermore obtain sensed channel voltages associated with each of the LED channels, and configure the shared voltage supply based on the sensed channel voltages to a voltage level sufficient to drive all of the LED channels.

Abstract: The present inventions presents an LED lighting device for preventing flickering. The device comprises: a rectification unit receiving an alternating current voltage applied from an alternating current power source and rectifying the same so as to output a direct current; a first light-emitting unit receiving the direct current applied thereto and adjusting a first constant current so as to make a first LED array emit light; a second light-emitting unit receiving the adjusted first constant current applied thereto and adjusting a second constant current so as to make a second LED array emit light; and a serial switching unit receiving the direct current and the adjusted first and second constant currents applied thereto so as to control current transmission according to the opening/closing of a plurality of embedded transistors, wherein the direct current and the first constant current, which are to be applied, are applied by passing through first and second diodes, respectively.

Abstract: Circuitry and methods are provided for dynamically controlling the operating frequency of a resonant power converter. A feedback circuit generates error signals representing a difference between sensed output voltages and a constant target output voltage. A controller comprises a frequency control input terminal, and generates drive signals to half-bridge switching elements at determined operating frequencies. A frequency control circuit is coupled between the feedback circuit and the frequency control input terminal. The frequency control circuit sets minimum and maximum operating frequencies for the controller, and dynamically adjusts the operating frequency with respect to the constant target output voltage. A frequency control power supply circuit may further provide signals to the frequency control circuit representative of voltage across the resonant capacitor, wherein the minimum operating frequency is dependent thereon.

Abstract: A lighting circuit controls lighting/extinguishing of a light source. A driving circuit generates a driving current which is to be supplied to the light source. A clamp circuit clamps a voltage between both ends of the light source to a clamp level in a period in which the light source is to be turned off. The clamp level is defined to be higher than zero and lower than a critical pressure when the light source is turned on/off.

Abstract: A lighting device for multiple input voltages is provided. The lighting device for multiple input voltages includes a plurality of driving circuits each being electrically connected with the light-emitting unit. Each of the driving circuits receives an AC input voltage, and converts the AC input voltage into a working voltage for use by the light-emitting unit. Each of the driving circuits includes a surge protection device and a rectifier. The surge protection device inputs the AC input voltage. The rectifier is electrically connected with the surge protection device, and rectifies the AC input voltage into the working voltage through the surge protection device for use by the light-emitting unit. A threshold voltage of each of the surge protection devices to prevent a surge is different from each other, so that the AC input voltage received by the driving circuits are different from each other.

Abstract: An electrical device includes a first terminal structured to electrically connect to a power source; a second terminal structured to electrically connect to a load; a voltage sensor electrically connected to a point between the first and second terminals and being structured to sense a voltage at the point between the first and second terminals; a switch electrically connected between the first terminal and the second terminal; and a control unit structured to detect a power quality event in the power flowing between the first and second terminals based on the sensed voltage and to control a state of the switch based on the detected power quality event.

Abstract: Various improvements are provided to resonant DC/DC and AC/DC converter circuit. The improvements are of particular interest for LLC circuits. Some examples relate to self-oscillating circuit and others relate to converter circuits with frequency control, for example for power factor correction, driven by an oscillator.

Abstract: A circuit comprises an amplifier and a plurality of channels, the plurality of channels including respective transistors. The respective transistors of the channels control respective magnitudes of respective currents of the channels according to an output of the amplifier. The respective transistors of the plurality of channels may be included in an auto-commutated circuit. A first Light Emitting Diode (LED) circuit may be coupled between a power source and a first channel of the plurality of channels. A second LED circuit may be coupled between the first channel and a second channel of the plurality of LED channels. The power source may provide rectified Alternating Current (AC).

Abstract: A bridge circuit (22) includes a first light-emitting element group (102, 110) and a second light-emitting element group (103, 120) connected in series; and a pair of comparison resistors (201, 202) connected in series and generating a voltage (Vref) equivalent to a voltage (VLED) at a connecting point between the first light-emitting element group (102, 110) and the second light-emitting element group (103, 120). A transistor (301, 302) is connected to a connecting point between the first light-emitting element group (102, 110) and the second light-emitting element group (103, 120) and a connecting point between the comparison resistors (201, 202), and operates when the first light-emitting element group (102, 110) or the second light-emitting element group (103, 120) is short-circuited.

Abstract: A current source circuit and an LED driving circuit applying the same. A current at an output terminal of an operational transconductance amplifier is shunted based on a first control signal that includes duty cycle information, or an input signal at at least one input terminal of the operational transconductance amplifier is controlled to be switched between different voltage signals based on the first control signal, so as to adjust an output current of a current adjustment circuit. A driving voltage for driving a current generation circuit is adjusted based on the output current. Thereby, a driving current generated by the current source circuit is correlated with the duty cycle information. An amplitude modulation circuit used, a low-pass filter and the like for processing the first control signal are not used, effectively simplifying circuit design and improving system efficiency.

Abstract: An LED lighting apparatus capable of color temperature control includes a color temperature controller to receive a color temperature selection signal and output first and second control signals; a LED driver connected a plurality of LED groups; and a LED selection circuit including a first switch connected to a first node to which a rectified voltage is applied and receiving the first control signal, a first LED group selectively connected to the first node by the first switch, a second LED group connected in series with the first LED group, a third LED group selectively connected to the first node by the first switch, a fourth LED group connected in series with the third LED group, and a second switch for selectively connecting the output terminal of the second LED group or the fourth LED group to the LED driver by receiving the second control signal.

Abstract: An autonomous vehicle is disclosed. The vehicle comprises a chassis, two or more drive wheels extending below the chassis, a drive motor housed within the chassis for driving the drive wheels, and a payload surface on top of the chassis for carrying a payload. An illumination system, for emitting light from at least one portion of the chassis, is mounted substantially around the entire perimeter of the chassis. The illumination system may be implemented using an array of light-emitting diodes (“LEDs”) that are arranged as segments. For example, there may be “headlight” segments on the front left and front right corners of the chassis.

Abstract: A vehicle lighting device includes a plurality of circuit portions that have at least one light emitting element; and a control portion that is electrically connected to the plurality of circuit portions. The control portion detects an input voltage and connects the plurality of circuit portions in series when the detected input voltage exceeds a predetermined value and connects at least a part of the plurality of circuit portions in parallel when the detected input voltage is equal to or less than the predetermined value.

Abstract: A load control device may be configured to turn on lighting loads to obtain a fast turn-on time that may be substantially consistent across lighting loads that have different load voltages. The load control device may comprise a power converter circuit configured to produce a voltage across a capacitor, and a control circuit configured to control the power converter circuit to generate the voltage across the capacitor. The control circuit may determine a learned voltage from the magnitude of the voltage across the capacitor. For example, the control circuit may measure the magnitude of the voltage and store the measured voltage as the learned voltage. The control circuit may determine an operating parameter for the power converter circuit as a function of the learned voltage, and control the power converter circuit according to the operating parameter to charge the capacitor until the magnitude of the voltage exceeds a threshold.

Abstract: A current control circuit having a current regulation element, a first control circuit, and a second control circuit. The first control circuit is arranged to regulate, based on a reference current, a current flowing with respect to the current regulation element. The second control circuit is arranged to regulate, based on a reference voltage, a voltage across the current regulation element.

Abstract: The invention provides a circuit for LED illumination driving current linear adjustment and dimming control. The circuit for LED illumination driving current linear adjustment and dimming control includes AC power supply module, LED module, drive IC, dimming control module and linear current adjustment Module. The linear current adjustment module may control to reduce current flowing through LED module when input voltage is increased, to achieve balance of input power and improve linear adjustment rate thereof; and the dimming control module may alter the change of an internal reference voltage of the drive IC by external input voltage change, thereby realizing the change of the LED module current, cooperating with a holding current driving part, opening and closing a path for the holding current; therefore, the circuit can be applied to triac dimming applications, and the structure is compatible with 0-10V and PWM driving, thereby improving applicability.

Abstract: An optoelectronic semiconductor component is disclosed, comprising: a semiconductor body (1) having a semiconductor layer sequence (2) with a p-type semiconductor region (3), an n-type semiconductor region (5), and an active layer (4) arranged between the p-type semiconductor region (3) and the n-type semiconductor region (5); a support (10) having a plastic material and a first via (11) and a second via (12); a p-contact layer (7) and an n-contact layer (8), at least some regions of which are arranged between the support (10) and the semiconductor body (1), wherein the p-contact layer (7) connects the first via (11) to the p-type semiconductor region (3) and the n-contact layer (8, 8A) connects the second via (12) to the n-type semiconductor region (5); and an ESD protection element (15) which is arranged between the support (10) and the semiconductor body (1), wherein the ESD protection element (15) is electrically conductively connected to the first via (11) and to the second via (12), and wherein a forwar

Abstract: An illumination system comprising a light source including a linear array of color variable light emitting elements; a power supply coupled to the array; and a power regulating circuit, coupled between the power supply and the array, effective to activate the light emitting elements to emit light in accordance with a color profile that varies as a function of location on at least a portion of the array. In a specific implementation, the invention includes a camera or other sensor for detecting ambient lighting conditions. This enables the system to adjust the array to achieve ambient lighting conditions in accordance with user preferences or profile. In yet another embodiment, lighting conditions at a remote location at a specific time are sensed by a smartphone camera or other device and coupled to the power regulating circuit for use in adjusting the array to achieve a match of ambient lighting to that or a remote location and time, subject to user adjustments, profile and/or preferences.

Abstract: An apparatus for driving LEDs using high voltage includes two LED driving circuits and two switches controlled by a universal controller so as to connect the two LED driving circuits in two different configurations. Each LED driving circuit has an LED unit formed by a plurality of LED segments. Each LED segment has an associated bypass switch controlled by an LED controller to bypass or connect the LED segment in the LED unit. When an input voltage ranges from rectified 90 volt AC to rectified 140 volt AC, the two switches are controlled to connect the two LED driving circuits in parallel. When the input voltage ranges from rectified 180 volt AC to rectified 265 volt AC, the two switches are controlled to connect the LED segments of the LED unit in one LED driving circuit in series with the other LED driving circuit.

Abstract: A lighting module includes a light emitter including a first light-emitting diode (LED) string configured to emit light of a first color temperature and a second LED string configured to emit light of a second color temperature, a terminal unit configured to provide terminals capable of supplying a driving current to at least one of the first LED string and the second LED string, and a balancing unit including a first balance LED, a second balance LED, a first balance resistor, and a second balance resistor, the balancing unit configured to adjust a mixed color temperature, and reduce a luminance difference between the light of the mixed color temperature and one of the light of the first color temperature and the light of the second color temperature.

Abstract: Embodiments of wave-based lighting efficiencies are provided. As an example, a method includes determining a characteristic of a voltage from an alternating current (AC) waveform, where the AC waveform is configured to power a load, and wherein the AC waveform includes positive voltage portions, negative voltage portions, and zero axis points. Some embodiments include determining a first position in the AC waveform to create a first step with a first step voltage and applying the AC waveform at the first step to a first predetermined portion of the load, where the first predetermined portion of the load has a first voltage rating that corresponds to the first step voltage.

Abstract: An LED light string has a plug, a socket, a lighting string connected between the plug and the socket, and a control circuit provided in either the plug or the socket. The control circuit uses at least one current controller to control a driving current flowing through the lighting string stably. When a temperature of the lighting string exceeds a threshold, the current controller activates its over-temperature protection function to lower the driving current. When short-circuit occurs on the lighting string, the current controller activates its short-circuit protection function to lower the driving current.

Abstract: A method for optimizing the operation of a digital controller provided in a control loop for a step-up converter. The method includes: evaluating at least one output variable of the digital controller during operation of the step-up converter; estimating the instantaneous load resistance value in the path of the control loop based on the at least one evaluated output variable; setting at least one controller coefficient of the digital controller based on the estimated instantaneous load resistance value during operation of the step-up converter. A change in the setting of the at least one controller coefficient results in a change in the transition frequency in the control loop. Furthermore, a control loop for a step-up converter that includes a digital controller is provided, which is configured to carry out the steps of the method. A computer program product that includes computer-executable program code for carrying out the method.

Abstract: A ground fault detection circuit includes an input portion, and a ground fault determination unit. The input portion inputs an anode voltage of a series connection unit constituted of a plurality of light emission elements. When an anode voltage of the series connection unit input by the input portion is lower than or equal to a predetermined value less than a product of an on-resistance of the short-circuit switch disposed in parallel to each of the light emission elements and current supplied to the series connection unit, the ground fault determination unit determines that a ground fault has occurred without the short-circuit switch in a ground fault path.

Abstract: An electronic apparatus and a light-emitting module driving circuit thereof are provided. The electronic apparatus includes a light-emitting module and a driving circuit. The driving circuit is coupled to the light-emitting module and is configured to generate a driving signal set to drive the light-emitting module. The driving circuit includes a first driver, a second driver, and a switching circuit. The first driver receives a control signal related to an operation status of the electronic apparatus and generates a first signal set according to the control signal. The second driver includes at least one resistor which receives system power and accordingly generates a second signal set. The switching circuit is coupled to the first driver and the second driver to receive the first signal set and the second signal set, respectively. When the switching circuit does not receive the first signal set, the switching circuit takes the second signal set as the driving signal set.

Abstract: A light emitting diode (LED) driver circuit includes an LED string and a conducting state detection circuit. The conducting state detection circuit detects a conducting state of the LED string, and generates a discharge control signal upon sensing that the LED string is in a non-conducting state. A current source generates a discharge current according to the discharge control signal when the LED string is in the non-conducting state. A passive bleeder provides current compensation by internal regulator operation. An LED spike current suppression circuit suppresses spike current that can occur when the input voltage increases above a threshold. A bias supply circuit has an input capacitor that provides a bias voltage.

Abstract: An optoelectronic circuit for receiving a variable voltage containing alternating increasing and decreasing phases, the optoelectronic circuit including a plurality of groups of light-emitting diodes and a switching device for allowing or interrupting the circulation of a current through each group, the switching device also being suitable for detecting whether said variable voltage is supplied by a dimmer.

Abstract: A control device comprising at least one input connector (x1, x2) configured to electrically connect an operating device (1) for driving lighting means (3a, 3b), and at least one output connector (x3, x4, x5) configured to electrically connect at least one of the lighting means (3a, 3b), a control means (4) configured to switch the lighting means (3a, 3b) based on a control signal, and a circuit (5) configured to generate voltage for supplying the control means (4) from a constant current that is generated from the operating device (1) for driving the lighting means (3a, 3b).

Abstract: A dimming control power supply for LED lamps, comprises a first secondary power supply module, an output control module, a PWM signal receiving module, and a control signal converting module. The output control module is configured to adjust the output current according to the received constant DC voltage signal with a variable amplitude. The control signal converting module converts the PWM signal received by the PWM signal receiving module into a constant DC voltage signal with a variable amplitude. The output control module adjusts the output current according to the constant DC voltage signal with a variable amplitude to adjust the brightness of the LED lamps. The light source provided by the LED lamp powered by the dimming control power supply for the LED lamps doesn't form streaks in the photographs taken by the cell phone or the camera and thus enhances the user's light experience.

Abstract: An autonomous vehicle is disclosed. The vehicle comprises a chassis, two or more drive wheels extending below the chassis, a drive motor housed within the chassis for driving the drive wheels, and a payload surface on top of the chassis for carrying a payload. An illumination system, for emitting light from at least one portion of the chassis, is mounted substantially around the entire perimeter of the chassis. The illumination system may be implemented using an array of light-emitting diodes (“LEDs”) that are arranged as segments. For example, there may be “headlight” segments on the front left and front right corners of the chassis.

Abstract: Examples of the present disclosure are related to systems and methods for a voltage snubber circuit utilizing with light fixtures. More particularly, embodiments disclose a voltage snubber that is configured to prevent higher voltages being applied to a light emitting diode (LED) string.

Abstract: Aspects are described for dual-distribution lighting devices. For example, a dual-distribution lighting device includes a forward-throw module with a first lighting element that can provide directional light, a wide-throw module with a second lighting element that can provide light with a wide distribution, an interface element that can to receive input, and a processing device. In response to the input being received via the interface element, the processing device deactivates one of the forward-throw and wide-throw modules and activates the other of the forward-throw and wide-throw modules, thereby causing the dual-distribution lighting device to switch between providing directional light and a wide distribution of light.

Abstract: A pixel circuit, a driving method, an organic electroluminescent display panel, and a display device, the pixel circuit includes a light emitting element, a driving control module, a resetting control module, a charging control module, a writing control module, and a light emitting control module; the resetting control module resets the first node and the light emitting element; the charging control module charges the second node through the light emitting control module and discharges the second node through the driving control module and the resetting control module; the writing control module writes a data signal to the second node; and the light emitting control module controls the driving control module to drive the light emitting element to emit light.

Abstract: Apparatus, systems, and methods for controlling light output in a lighting system based on defined light profiles are provided. In one example implementation, a light fixture can include a first light emitting diode (LED) array having one or more LED light sources and a second LED array having one or more LED light sources. The light fixture can include a power circuit configured to provide power to the first LED array and the second LED array according to a power distribution among the first LED array and the second LED array. The light fixture can include one or more control devices configured to control the power circuit to adjust the power distribution among the first LED array and the second LED array based at least in part on a signal indicative of a real time clock and a defined light profile associated with a user identified to be present in a space illuminated by the light fixture.

Abstract: Disclosed in the present invention is a method for adjusting a color temperature of an LED in a single light fixture. In the method, at least two light-emitting modules in a single light fixture are respectively electrically connected to a switch, each light-emitting module is independently adjusted by a switch corresponding to the light-emitting module, and the light-emitting modules have different color temperatures. Therefore, the brightness of each light-emitting module can be respectively controlled by using each switch, so that emitted light of the single light fixture has more than three color temperatures.

Abstract: According to one embodiment, a light source device includes a plurality of light emitting elements including at least first and second light emitting elements, lightguide, first circuit, second circuit, and controller. The lightguide includes a first surface on which light from light emitting elements is incident and a second surface through which the light exits. The first circuit connects light emitting elements in series. The second circuit can bypass each of light emitting elements. The controller turns on light emitting elements using the first circuit if light emitting elements function normally, and if one of light emitting elements functions abnormally, the controller turns on the light emitting element functioning normally using the second circuit.

Abstract: Apparatus and systems are disclosed for detecting outages in an LED lamp assembly. An example disclosed lamp assembly includes a plurality of LED circuits serially connected together. The LED circuits include an LED, a first resistor and an optocouper. The example disclosed lamp assembly also includes a sense line electrically coupled to one of the LED circuits. The sense line has a first voltage value when all of LEDs in that plurality of LED circuits are operational and a second voltage value when at least one of the LEDs has failed.