A lighting status signaling system including a lighting fixture having a light, a light driver connected to the light, and a monitor circuit connected to the light and to the light driver. The monitor circuit is configured to monitor a voltage level at an output of the light driver. A sensing circuit is coupled to the monitor circuit via a sensing wire independent of a power wire to the lighting fixture. A lighting controller is connected to the sensing circuit via the sensing wire and configured to determine a lighting status of the lighting fixture.

A driver assembly (100) for a lighting unit (230) comprises a control unit (110). The lighting unit (230) comprises a plurality of strands (240, 250, 260), wherein each strand comprises a series circuit (242, 252, 262) of light-emitting diodes and a current source (243, 253, 263) with a first and a second terminal (246, 256, 266), and wherein the series circuit (242, 252, 262) of diodes is connected between a supply voltage input (231) of the lighting unit (230) and the first terminal of the current source (243, 253, 263) and the second terminal (246, 256, 266) of the current source is connected to a reference potential terminal via a resistor (245, 255, 265). The control unit (110) is designed for generating a corresponding control signal for a voltage converter (210) from a respectively adjusted control value, wherein said voltage converter is designed for making available an output voltage at the supply voltage input (231) of the lighting unit (230) based on the control signal, for acquiring a measured value at each of the second terminals (246, 256, 266) of the current sources (243, 253, 263), for storing an adjusted control value for each strand (240, 250, 260) based on the acquired measured values and for detecting whether an error condition exists in one of the strands (240, 250, 260) based on the stored control values.

A system includes lighting devices coupled to output supply pins, a microcontroller circuit, and a driver circuit, which receives data therefrom, and switches coupled in series to the lighting devices. The driver circuit includes output supply pins and selectively propagates a supply voltage to the output supply pins to provide respective pulse-width modulated supply signals at the output supply pins. The driver circuit computes duty-cycle values of the pulse-width modulated supply signals as a function of the data received from the microcontroller circuit. The lighting devices include at least one subset coupled to the same output supply pin. The microcontroller individually controls the switches via respective control signals to individually adjust a brightness of the lighting devices in the at least one subset of lighting devices.

This specification relates to a method and a system for detecting light emitting diode (LED) short circuit in a plurality of LED strings or detecting matching among the plurality of LED strings, wherein one end of each of the plurality of LED strings is connected to a same output end of a power supply, and the other end is respectively connected to a corresponding switch. According to the present invention, first current of each of LED strings is obtained when the output end of the power supply outputs a first voltage; differences between the minimum of the first currents of LED strings and other first currents are calculated; the differences are compared with a comparing threshold; it is determined that the LED strings corresponding to the other currents for which differences are larger than the comparing threshold include short circuit or mismatch with the LED string corresponding to the minimum current. Accordingly, it is possible to reduce the number of pins and area of a control chip.

This disclosure includes systems, methods, and techniques for detecting one or more short connections in a plurality of light-emitting diode (LED) channels. For example, a circuit includes processing circuitry configured to control a plurality of driving devices in order to cause a pair of LED channels of the plurality of LED channels to operate in a first state during a first period of time and operate in a second state during a second period of time. Additionally, the processing circuitry is configured to compare a first electrical signal corresponding to the first state of the pair of LED channels and a second electrical signal corresponding to the second state of the pair of LED channels and determine, based on the comparison of the first electrical signal and the second electrical signal, if a short connection exists between the pair of LED channels.

This disclosure includes systems, methods, and techniques for detecting one or more short connections in a plurality of light-emitting diode (LED) channels. For example, a circuit includes processing circuitry configured to control a plurality of driving devices in order to cause a pair of LED channels of the plurality of LED channels to operate in a first state during a first period of time and operate in a second state during a second period of time. Additionally, the processing circuitry is configured to compare a first electrical signal corresponding to the first state of the pair of LED channels and a second electrical signal corresponding to the second state of the pair of LED channels and determine, based on the comparison of the first electrical signal and the second electrical signal, if a short connection exists between the pair of LED channels.

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 output terminals, thereby connecting said LED driver to said LED lighting device; wherein said biased DPDT switch is further arranged to toggle from said short circuit position to said connected position upon insertion of said LED lighting device into said receiving means of said socket. A corresponding method of toggling a switch is also presented herein.

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 output terminals, thereby connecting said LED driver to said LED lighting device; wherein said biased DPDT switch is further arranged to toggle from said short circuit position to said connected position upon insertion of said LED lighting device into said receiving means of said socket. A corresponding method of toggling a switch is also presented herein.

A method for identifying a short in a first light emitting diode element may include providing a first actuating circuit being a switched-off condition, wherein an output thereof is coupled to a first electrode of the first light emitting diode element, providing a second actuating circuit being a switched-off condition, wherein an output thereof is coupled to a first electrode of a second light emitting diode element and wherein inputs of the first and second actuating circuits, second electrodes of the first and second light emitting diode elements are electrically coupled to a first node, coupling the first electrode of the first light emitting diode element to a first connection of a test energy source, operating the first light emitting diode element in the off-state region using the test energy source, performing a check whether an electric current flows via the first light emitting diode element, and identifying the short.

An optoelectronic circuit includes at least one first and second light emitting diodes; a switch arrangement connected between the first and second diodes and configured to switch over the first and second diodes between series and parallel circuits depending on a predefined ambient parameter; and a current matching circuit for matching the currents through the first and second diodes in case of parallel connection. The current matching circuit includes a current mirror circuit, including first and second current mirror transistors connected via its collector terminal to the first/second diodes, respectively. The arrangement includes a diode/a switch for connecting the first diode in series with the second diode and is configured to form the series circuit including the first and second diodes whilst bypassing the current matching circuit so that, in case of series connection, the first transistor is switched in a high-resistance fashion and the second transistor is short-circuited.