Detecting LED fault conditions

Abstract

The present disclosure relates to detecting LED fault conditions, and in particular to systems, methods, and techniques for controlling a plurality of light emitting diodes (LEDs). For example, a circuit includes a switching device, where the switching device is electrically connected to an LED of the plurality of LEDs, and where the switching device is configured to control whether the LED receives an electrical signal from a power source. Further, the circuit includes a processing circuitry configured to determine that the LED is associated with a bright fault condition by using the switching device to attempt to prevent the LED from receiving the electrical signal from the power source, and to disable the LED in response to detecting the bright fault condition.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to circuits for driving and controlling light emitting diodes. BACKGROUND

[0002] Driver circuits are commonly used to control voltage, current, or power on a load. For example, a light emitting diode (LED) driver can control power provided to a string of light emitting diodes. In some cases, an LED driver circuit can accept an input signal including an input current and an input voltage, and deliver an output signal including an output current and an output voltage. In some such cases, the LED driver circuit can regulate at least some aspects of the input signal and the output signal, such as controlling the output current emitted by the LED driver circuit. In some examples, the LED driver circuit can control the light intensity of a corresponding LED. SUMMARY

[0003] Generally, the present disclosure relates to one or more systems, apparatuses, and techniques for detecting whether one or more failure conditions exist for each light emitting diode (LED) of a plurality of LEDs. For example, a failure condition can include a "bright failure" condition that prevents a controller from turning off an LED, a "dark failure" condition that prevents a controller from turning on an LED, a "dim light" condition in which an LED fails to achieve a brightness greater than a threshold level when turned on. In some cases, a processing circuit apparatus can be configured to perform a test on a plurality of LEDs in order to identify one or more LEDs of the plurality of LEDs, and subsequently perform one or more actions in order to correct, change, or eliminate the failure. For example, the processing circuit apparatus can determine that a group of LEDs of the plurality of LEDs are associated with a bright failure condition. It can be beneficial for the processing circuit apparatus to disable the group of LEDs associated with the bright failure condition such that the group of LEDs do not continue to emit light when the controller turns off the plurality of LEDs.

[0004] In some examples, a circuit controls a plurality of LEDs. The circuit includes a switching device and a processing circuit apparatus, where the switching device is electrically connected to one LED of the plurality of LEDs, and where the switching device is configured to control whether the LED receives an electrical signal from a power source. The processing circuit apparatus is configured to determine that the LED is associated with a bright failure condition by attempting to prevent the LED from receiving the electrical signal from the power source using the switching device; and disable the LED in response to detecting the bright failure condition.

[0005] In some examples, a method for controlling a plurality of LEDs includes: controlling whether one LED of the plurality of LEDs receives an electrical signal from a power source; determining, by a processing circuit apparatus, that the LED is associated with a bright failure condition by attempting to prevent the LED from receiving the electrical signal from the power source using a switching device, where the switching device is electrically connected to the LED; and disabling, by the processing circuit apparatus, the LED in response to detecting the bright failure condition.

[0006] In some examples, a system for controlling a plurality of LEDs includes a plurality of LEDs, a switching device, and a processing circuitry, wherein the switching device is electrically connected to one of the plurality of LEDs, and wherein the switching device is configured to control whether the LED receives an electrical signal from a power source. The processing circuitry is configured to: determine that the LED is associated with a bright fault condition by attempting to prevent the LED from receiving the electrical signal from the power source using the switching device; and disable the LED in response to detecting the bright fault condition.

[0007] SUMMARY The summary is intended to provide an overview of the subject matter described in this disclosure. The summary is not intended to provide an exclusive or exhaustive explanation of the systems, apparatuses, and methods described in detail in the accompanying drawings and the following description. Further details of one or more examples of the present disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will be apparent from the description and drawings. BRIEF DESCRIPTION OF DRAWINGS

[0008] Figure 1 is a block diagram illustrating a system for detecting one or more fault conditions in a plurality of LEDs in accordance with one or more techniques of the present disclosure.

[0009] Figure 2A is a circuit diagram illustrating a system for testing one or more fault conditions in accordance with one or more techniques of the present disclosure.

[0010] Figure 2B is a circuit diagram illustrating a system including a short-to-ground connection in accordance with one or more techniques of the present disclosure.

[0011] Figure 2C is a circuit diagram illustrating a system including a short-to-battery connection in accordance with one or more techniques of the present disclosure.

[0012] Figure 2D is a circuit diagram illustrating a system including a weak connection in accordance with one or more techniques of the present disclosure.

[0013] Figure 3A is a circuit diagram illustrating a high-side configuration of a system for testing one or more fault conditions of an LED in accordance with one or more techniques of the present disclosure.

[0014] Figure 3B is a circuit diagram illustrating a high-side configuration of another system for testing one or more fault conditions of an LED in accordance with one or more techniques of the present disclosure.

[0015] Figure 4A is a circuit diagram illustrating a system for detecting a bright fault condition caused by a short-to-ground connection in accordance with one or more techniques of the present disclosure.

[0016] Figure 4B is a circuit diagram illustrating a system for detecting a bright fault condition caused by a shorted connection to a battery in accordance with one or more techniques of the present disclosure.

[0017] Figure 4C is a circuit diagram illustrating a system for detecting a dark fault condition caused by an open connection in accordance with one or more techniques of the present disclosure.

[0018] Figure 4D is a circuit diagram illustrating a system for detecting a weak light fault condition caused by a weak connection in accordance with one or more techniques of the present disclosure.

[0019] Figure 5 is a flowchart illustrating example operations for identifying one or more LEDs associated with a bright fault condition in accordance with one or more techniques of the present disclosure.

[0020] Throughout the description and drawings, like reference numerals refer to like elements. DETAILED DESCRIPTION

[0021] Some lighting systems can control a set of switching devices, where each switching device in the set of switching devices controls whether a respective light emitting diode (LED) in a plurality of LEDs receives an electrical signal from a power source. In some examples, the system can perform a test in order to identify whether each LED in the plurality of LEDs is associated with one or more fault conditions. In some cases, the system can change, correct, or eliminate a fault condition associated with an LED in the plurality of LEDs. The system can include a sensing device configured to detect a set of LEDs associated with a bright fault condition, the bright fault condition preventing each LED in the set of LEDs from turning off. It can be beneficial for the system to disable the set of LEDs associated with the bright fault condition. For example, the plurality of LEDs can form an LED matrix, and the system can attempt to turn off each LED in the plurality of LEDs such that the plurality of LEDs do not emit any visible light. Since the set of LEDs associated with the bright fault condition can continue to emit light after the system attempts to turn off the set of LEDs, the system can disable the set of LEDs to prevent a situation where the LEDs continue to produce light while the system attempts to prevent the LEDs from producing light.

[0022] In some examples, systems including multiple LEDs can present one or more technical problems. In particular, one or more individual LEDs can exhibit a bright failure condition. This can result in the LEDs exhibiting a bright failure condition appearing as a light point in a matrix including multiple LEDs, which is undesirable. The present disclosure provides example techniques that address these problems by using circuitry to permanently disable LEDs exhibiting a bright failure condition. In some examples, the techniques of the present disclosure can also address weak light failure and dark failure problems of one or more LEDs. To this end, the techniques can permanently disable LEDs exhibiting a weak light failure condition and permanently disable LEDs exhibiting a dark failure condition. The techniques can include one or more techniques for permanently disabling select LEDs when the system is in a high-side configuration and one or more techniques for permanently disabling select LEDs when the system is in a low-side configuration.

[0023] Figure 1 is a block diagram illustrating a system 100 for detecting one or more failure conditions in a plurality of LEDs 112 in accordance with one or more techniques of the present disclosure. As Figure 1 shown, the system 100 includes a processing circuitry 102, a first power source 104, a power switch 106, LEDs 112, a node 114, a first set of switching devices 116, a second set of switching devices 122, a second power source 124, a third set of switching devices 132, and a sensing device 134.

[0024] In some examples, the system 100 represents a system for controlling each of the LEDs 112 as to whether each of the LEDs 112 receives power from the first power source 104. Further, in some examples, the system 100 represents a system for determining whether each of the LEDs 112 is associated with one or more failure conditions, such as a bright failure condition, a dark failure condition, or a weak light failure condition. Even when the processing circuitry 102 attempts to turn off LEDs associated with a bright failure condition, these LEDs can emit light, thus making it difficult to completely stop the LEDs 112 from turning off and ceasing to produce light. Accordingly, it can be beneficial to permanently disable LEDs associated with a bright failure condition. Further, in some cases, it can be beneficial to permanently disable LEDs associated with a weak light failure condition, as these LEDs can not be able to produce light greater than a threshold light intensity, and it can be better to remove these LEDs from operation.

[0025] In some examples, the processing circuitry 102 can include one or more processors configured to implement functionality and / or process instructions for execution within the system 100. For example, the processing circuitry 102 can be capable of processing instructions stored in the memory Figure 1The processing circuitry 102 can include, for example, microprocessors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or equivalent discrete or integrated logic circuitry, or combinations of any of the foregoing. Accordingly, the processing circuitry 102 can include any suitable structure, whether in hardware, software, firmware, or any combination thereof, to perform the functions described herein as being performed by the processing circuitry 102.

[0026] In some examples, the memory in communication with the processing circuitry 102 includes computer-readable instructions that, when executed by the processing circuitry 102, cause the system 100 to perform various functions attributed herein to the system 100. The memory can include any volatile, nonvolatile, magnetic, optical, or electrical media, such as a random access memory (RAM), read-only memory (ROM), non-volatile RAM (NVRAM), electrically-erasable programmable ROM (EEPROM), flash memory, or any other digital media.

[0027] The first power source 104 is configured to deliver operating power to one or more components of the system 100. In some examples, the first power source 104 includes a battery and power generation circuitry to generate the operating power. In some examples, the first power source 104 is rechargeable to allow extended operation. The first power source 104 can include any one or more of a plurality of different battery types, such as nickel cadmium, and lithium ion. In some examples, the first power source 104 has a maximum voltage output of approximately 12V. In some examples, the first power source 104 provides power in a range from 10 to 15 Watts (W). A power switch 106 can represent a switch that controls the flow of current from the first power source 104 to the LEDs 112 such that the LEDs 112 emit photons (e.g., light). For example, when the power switch is turned off (e.g., open), the first power source 104 is unable to provide power to the LEDs 112, and when the power switch is turned on (e.g., closed), the first power source 104 is able to provide power to the LEDs 112.

[0028] The LEDs 112 can include any suitable semiconductor light source. In some examples, the LEDs can include a p-n junction configured to emit light when activated. In some examples, the LEDs 112 can be included in a headlamp assembly for automotive applications. For example, the LEDs 112 can include a matrix, string, or more than one string of light emitting diodes to illuminate a road in front of a vehicle. As used herein, a vehicle can refer to a motorcycle, truck, boat, golf cart, snowmobile, heavy machinery, or any type of vehicle that uses directional lighting.

[0029] In some cases, any one or a combination of power switch 106, first set of switching devices 116, second set of switching devices 122, and third set of switching devices 132 (collectively referred to as “switching devices 106, 116, 122, 132”) can include a power switch such as, but not limited to, any type of field effect transistor (FET) including a metal oxide semiconductor field effect transistor (MOSFET), a bipolar junction transistor (BJT), an insulated gate bipolar transistor (IGBT), a junction field effect transistor (JFET), a high electron mobility transistor (HEMT), or any combination of other elements that are controlled using voltage or current. Further, switching devices 106, 116, 122, 132 can include n-type transistors, p-type transistors, and power transistors, or any combination thereof. In some examples, switching devices 106, 116, 122, 132 include vertical transistors, lateral transistors, and / or horizontal transistors. In some examples, switching devices 106, 116, 122, 132 include other analog devices such as diodes and / or thyristors. In some examples, switching devices 106, 116, 122, 132 can operate as switches and / or as analog devices.

[0030] In some examples, each of the switching devices 106, 116, 122, 132 includes three terminals: two load terminals and one control terminal. For MOSFET switches, each of the switching devices 106, 116, 122, 132 can include a drain terminal, a source terminal, and at least one gate terminal, where the control terminal is the gate terminal. For BJT switches, the control terminal can be the base terminal. Based on a voltage at the respective control terminal, current can flow between the two load terminals of each of the switching devices 106, 116, 122, 132. Thus, current can flow through the switching devices 106, 116, 122, 132 based on control signals communicated by the processing circuitry 102 to the respective control terminals of the switching devices 116. In one example, if a voltage applied to the control terminal of one or more of the switching devices 106, 116, 122, 132 is greater than or equal to a voltage threshold, the one or more of the switching devices 106, 116, 122, 132 can turn on, allowing the one or more of the switching devices 106, 116, 122, 132 to conduct electricity. Further, when the voltage applied to the respective control terminal of the one or more of the switching devices 106, 116, 122, 132 is below the threshold voltage, the one or more of the switching devices 106, 116, 122, 132 can be deactivated, thereby preventing the one or more of the switching devices 106, 116, 122, 132 from conducting electricity. The processing circuitry 102 can be configured to individually control the switching devices 106, 116, 122, 132 such that one, a combination, all, or none of the switching devices 106, 116, 122, 132 are on at a certain point in time.

[0031] The switching devices 106, 116, 122, 132 can include various material compounds, such as silicon, silicon carbide, gallium nitride, or any other combination of one or more semiconductor materials. In some examples, silicon carbide switches can experience lower switching power losses. Improved magnetism and faster switching, such as gallium nitride switches, can allow the switching devices 106, 116, 122, 132 to draw short pulse currents. These high frequency switching devices can need to send control signals (e.g., voltage signals communicated by the processing circuitry 102 to the respective control terminals of the switching devices 106, 116, 122, 132) with more precise timing as compared to low frequency switching devices.

[0032] Each of the first set of switching devices 116 can control the amount of electrical current that a respective LED of the LEDs 112 receives from the first power source 104. In other words, each of the LEDs 112 can be electrically connected to a respective one of the switching devices 116. When one of the first set of switching devices 116 is turned on, electrical current can flow from the first power source 104 through one of the LEDs 112 corresponding to that switching device and through the switching device itself, causing that LED to emit photons (e.g., light). When that switching device is turned off, that switching device can prevent electrical current from flowing through the corresponding LED of the LEDs 112, thereby preventing the LED from emitting photons.

[0033] The nodes 114 can include one node corresponding to each of the LEDs 112. In some examples, one of the nodes 114 can electrically connect one of the LEDs 112 with a respective one of the first set of switching devices 116, a respective one of the second set of switching devices 122, and a respective one of the third set of switching devices 132. In this way, each of one of the first set of switching devices 116, one of the second set of switching devices 122, and one of the third set of switching devices 132 can be configured to receive at least a portion of an output electrical signal from a respective one of the LEDs 112.

[0034] In some examples, the processing circuitry 102 is configured to determine that a set of the LEDs 112 are associated with a bright failure condition by attempting to prevent each of the LEDs 112 from receiving an electrical signal from the first power source 104 using a respective one of the first set of switching devices 116. For example, the processing circuitry 102 can turn off each of the first set of switching devices 116. Additionally, in some cases, the processing circuitry can turn on each of the third set of switching devices 132. Each of the third set of switching devices 132 is configured to electrically connect or electrically disconnect each of the LEDs 112 with the sensing device 134.

[0035] The sensing device 134 includes circuitry configured to detect an electrical signal flowing through each of the LEDs 112 that are electrically connected to the sensing device 134. Thus, when the processing circuitry 102 turns on all of the third group of switching devices 132 and turns off all of the first group of switching devices 116, the processing circuitry 102 can be configured to determine a level of electrical current flowing through each of the LEDs 112 based on the sensing signals generated by the sensing device 134. The processing circuitry 102 can be configured to determine a group of the LEDs 112 that continue to conduct electrical current above a current threshold when a respective one of the first group of switching devices 116 is turned off based on the sensing signals. The processing circuitry 102 can identify the group of LEDs that continue to conduct electrical current above the current threshold as being associated with a bright fault condition.

[0036] In some cases, the processing circuitry 102 can disable the group of LEDs that the processing circuitry 102 determined to be associated with a bright fault condition. In some examples, the processing circuitry 102 disables the group of LEDs associated with a bright fault condition by controlling the second group of switching devices 122. Each of the second group of switching devices 122 is configured to electrically connect or disconnect each of the LEDs 112 to the second power source 124. In some cases, to disable the group of LEDs that the processing circuitry 102 determined to be associated with a bright fault condition, the processing circuitry 102 can turn on each of the second group of switching devices 122 that is electrically connected to the LEDs 112 that the processing circuitry 102 determined to be associated with a bright fault condition. In this way, the second group of switching devices 122 can electrically connect the second power source 124 to the group of LEDs associated with a bright fault condition.

[0037] The second power source 124 can apply a voltage to the group of LEDs associated with a bright fault condition in order to permanently disable the group of LEDs associated with a bright fault condition. In some examples, the second power source 124 can apply a voltage in order to disable the group of LEDs individually (e.g., one at a time). In some examples, the second power source 124 can apply a voltage in order to disable each of the group of LEDs at the same time. In any case, the processing circuitry 102 can convert the LEDs associated with a bright fault to LEDs associated with a dark fault by permanently disabling the LEDs associated with a bright fault such that they are unable to emit photons.

[0038] In some examples, the processing circuitry 102 can determine that one or more of the LEDs 112 are associated with a weak light fault condition. For example, the processing circuitry 102 can turn on all of the first set of switching devices 116 and turn on all of the third set of switching devices 132 and generate a sense signal. Subsequently, the processing circuitry 102 can determine a set of LEDs 112 associated with a weak light fault condition based on the sense signal. A weak light fault condition can represent a condition in which an LED emits light but does not emit as much light as one or more other LEDs not associated with the weak light fault condition. It can be beneficial to disable the LEDs associated with the weak light fault condition such that each of the LEDs 112 that are turned on emit a uniform level of light. The processing circuitry 102 can control the second set of switching devices 122 in order to disable the set of LEDs associated with the weak light fault condition. Additionally, or alternatively, the processing circuitry 102 can identify a set of LEDs associated with a dark fault condition.

[0039] Figure 1 The system of FIG. 1 can represent a“low-side” configuration in which the LEDs 112 are placed between the first power supply 104 and the first set of switching devices 116. A“high-side” configuration is also possible in which the switching devices are placed between the power supply and a set of LEDs.

[0040] Figure 2A is a circuit diagram illustrating a system 200A for testing one or more fault conditions of LEDs 212A-212N in accordance with one or more techniques of the present disclosure. As shown in Figure 2A , the system 200A includes a processing circuitry 202, a first power supply 204, a power switch 206, LEDs 212A-212N (collectively,“LEDs 212”), nodes 214A-214N (collectively,“nodes 214”), a first set of switching devices 216A-216N (collectively,“switching devices 216”), internal elements 218A-218N (collectively,“internal elements 218”), a ground pin 219, a force pin 220, a second set of switching devices 222A-222N (collectively,“switching devices 222”), a second power supply 224, a sense pad 230, a third set of switching devices 232A-232N (collectively,“switching devices 232”), and a sensing device 234. The processing circuitry 202 can be an example of the processing circuitry 102 shown in Figure 1 . The first power supply 204 can be an example of the first power supply 104 shown in Figure 1 . The power switch 206 can be an example of the power switch 106 shown in Figure 1 . The LEDs 212 can be an example of the LEDs 112 shown in Figure 1 . The nodes 214 can be an example of the nodes 114 shown in Figure 1 . The first set of switching devices 216 can be an example of the first set of switching devices 116 shown inFigure 1 An example of the first set of switching devices 116. The second set of switching devices 222 can be... Figure 1 An example of the second set of switching devices 122. The second power supply 224 can be... Figure 1 An example of the second power supply 124. The third set of switching devices 232 can be... Figure 1 An example of the third set of switching devices 132. The sensing device 234 may be... Figure 1 Example of sensing device 134.

[0041] Switching devices 116, 222, and 232 can form a switching matrix that controls whether each LED in LED 112 receives power from the first power supply 204, controls whether the second power supply 224 transmits a force signal to each LED in LED 112, and controls whether the sensing device 234 receives an output electrical signal from each LED in LED 112. For example, each node in node 214 can electrically connect one LED in LED 212 to a corresponding switching device in switching devices 216, 222, and 232. Node 214A is electrically connected to LED 212A, switching device 216A, 222A, and 232A. Node 214B is electrically connected to LED 212B, switching device 216B, 222B, and 232B. Node 214C is electrically connected to LED 212C, switch 216C, switch 222C, and switch 232C. Node 214N is electrically connected to LED 212N, switch 216N, switch 222N, and switch 232N.

[0042] Processing circuitry 202 can test each of the LEDs in LED 212 to determine whether the corresponding LED is associated with a lighting fault condition (e.g., the LED emits light when it should be off). For example, LED 212B may be associated with a lighting fault condition. Processing circuitry 202 can turn on / off switching device 216B, which controls whether LED 212B receives current from the first power supply 204. In one or more examples where LED 212B is associated with a lighting fault condition, one or more short-circuit connections ( Figure 2A (Not shown) This can cause current to flow through LED 212B, causing LED 212B to light up even when switching device 216B is turned off, while processing circuit device 202 attempts to prevent LED 212B from emitting light by turning off switching device 216B. Processing circuit device 202 can test LED 212B and each of the other LEDs in LED 212 to determine a set of LEDs associated with the lighting fault condition.

[0043] In some examples, to test for a bright-fail condition for each of the LEDs 212, the processing circuitry 202 can turn off each of the switching devices 216 in order to attempt to block current flow through the LEDs 212 to the ground pin 219. Further, in some cases, the processing circuitry 202 can turn on each of the switching devices 232N, allowing the sensing device 234 to detect an electrical signal corresponding to each of the LEDs 212. The electrical signal corresponding to each of the LEDs 212 can be indicative of an amount of current flowing through each of the LEDs 212. For example, the electrical signal corresponding to each of the LEDs 212 can be indicative of whether no current is flowing through each respective LED of the LEDs 212, and the electrical signal corresponding to each of the LEDs 212 can be indicative of whether at least some current is flowing through each respective LED of the LEDs 212. When the switching devices 232A-232N are turned on and the switching devices 216A-216N are turned off, the sensing device 234 can output the electrical signal corresponding to each of the LEDs 212A-212N to the processing circuitry 202, allowing the processing circuitry 202 to determine the amount of current flowing through each of the LEDs 212.

[0044] The processing circuitry 202 can determine that each of the LEDs 212 for which the current flowing through the respective LED is greater than a threshold amount is associated with a bright-fail condition. In certain examples, the threshold amount of current can be zero microamperes (pA) or very close to zero pA (e.g., less than 1 pA). In this way, if the current flowing through an LED of the LEDs 212 exceeds a trace level while the respective one of the switching devices 216 is turned off, the processing circuitry 202 can determine that the LED is associated with a bright-fail condition. In certain examples, the threshold amount of current can be greater than 30 pA. In certain examples, the threshold amount of current can be greater than 100 pA. In certain examples, the threshold amount of current can be in a range of 15 pA to 150 pA. In this way, a significant amount of current must flow through an LED before the processing circuitry 202 determines that the LED is associated with a bright-fail condition.

[0045] In some examples, the processing circuitry can test each of the LEDs 212 in order to determine whether the LEDs are associated with a bright fault condition during a time window. For example, the sensing device 234 can receive an electrical signal corresponding to each of the LEDs 212 at a time. In some examples, the processing circuitry can test the bright fault condition of each of the LEDs 212 at staggered intervals (e.g., one at a time, two at a time, or any other combination). For example, the processing circuitry 202 can turn off the switching device 216A and turn on the switching device 232A, allowing the processing circuitry 202 to test the bright fault condition of the LED 212A. Subsequently, the processing circuitry 202 can turn off the switching device 216B and turn on the switching device 232B, allowing the processing circuitry 202 to test the bright fault condition of the LED 212B, and then the processing circuitry 202 can turn off the switching device 216C and turn on the switching device 232C, allowing the processing circuitry 202 to test the bright fault condition of the LED 212C, and so on.

[0046] In some examples, it can be beneficial to convert the LEDs associated with the bright fault condition to LEDs associated with a dark fault condition by permanently preventing the LEDs associated with the bright fault condition from emitting light. This is because, in some cases, the LEDs 212 can form a matrix, and sometimes the processing circuitry 202 can attempt to turn off each of the LEDs in the matrix. If some of the LEDs continue to emit light when the processing circuitry 202 outputs a command to turn off all of the LEDs, the LED matrix can appear to emit some light points, which is undesirable. The processing circuitry 202 can determine a group of LEDs 212 that are associated with the bright fault condition. In some examples, the group of LEDs can include the LED 212B. Subsequently, the processing circuitry 202 can disable each of the LEDs in the group of LEDs associated with the bright fault condition.

[0047] The processing circuitry 202 can disable the LED 212B in response to determining that the LED 212B is associated with the bright fault condition. For example, the processing circuitry 202 can turn on the switching device 222B, electrically connecting the second power source 224 to the LED 212B via the node 214B. In turn, the second power source 224 can deliver a forced electrical signal to the cathode of the LED 212B. In some examples, a forced electrical signal can disable an LED if one or more parameters of the forced electrical signal delivered to the cathode of the LED in the LED 212 is greater than a threshold parameter value. For example, the forced electrical signal can represent a 4V electrical signal. This 4V signal can cause the LED to be disabled when applied to the cathode of the respective LED.

[0048] In some examples, the processing circuitry can perform one or more tests in order to determine whether each of the LEDs 112 is associated with a dark fault condition and / or a dim light fault condition. For example, to test whether an LED (e.g., LED 212A) in the LEDs 212 is associated with a dark fault condition, the processing circuitry 202 can turn on the switching device 216A, establishing a connection between the first power source 204 and the ground pin 219 through the LED 212A. The processing circuitry 202 can turn on the switching device 232A so that the sensing device 234 can detect an electrical signal indicative of an amount of current flowing through the LED 212A. If the current flowing through the LED 212A when the switching device 216A is on is less than a threshold amount, the processing circuitry 202 can determine that the LED 212A is associated with a dark fault condition. In certain examples, the threshold amount of current can be zero mA or very close to zero mA (e.g., less than 1 mA). In this way, if no current or almost no current flows through the LED 212A when the switching device 216A is on, the processing circuitry 202 can determine that the LED 212A is associated with a dark fault condition.

[0049] To test whether an LED (e.g., LED 212C) in the LEDs 212 is associated with a dim light fault condition, the processing circuitry 202 can turn on the switching device 216C, establishing a connection between the first power source 204 and the ground pin 219 through the LED 212C. The processing circuitry 202 can turn on the switching device 232C so that the sensing device 234 can detect an electrical signal indicative of an amount of current flowing through the LED 212C. When the amount of current flowing through the LED 212C while the switching device 216A is on is within a range from a lower current threshold to an upper current threshold, the processing circuitry 202 can determine that the LED 212C is associated with a dim light fault condition. In some examples, the processing circuitry 202 can disable one or more LEDs associated with a dim light fault condition.

[0050] The processing circuitry 202 can disable the LED 212C in response to determining that the LED 212C is associated with a dim light fault condition. For example, the processing circuitry 202 can turn on the switching device 222C, electrically connecting the second power source 224 with the LED 212C via the node 214C. In turn, the second power source 24 can deliver a forced electrical signal to the cathode of the LED 212C. In some examples, a forced electrical signal can disable an LED if one or more parameters of the forced electrical signal delivered to the cathode of an LED in the LEDs 212 is greater than a threshold parameter value. For example, the forced electrical signal can represent a 4V electrical signal. This 4V signal can disable an LED when applied to the cathode of the respective LED.

[0051] Although LED 212A is described as being associated with a dark fault condition, LED 212B is described as being associated with a bright fault condition, and LED 212C is described as being associated with a dim light fault condition, this is not required. Each of the LEDs 212 can be associated with any one or combination of the fault conditions described herein, or can not be associated with any of the fault conditions described herein.

[0052] Figure 2B is a circuit diagram illustrating a system 200B including a short-to- ground connection 237 in accordance with one or more techniques of the present disclosure. In some examples, the system 200B can be substantially identical to the system 200A, except that the LED 212B is connected to the short-to-ground connection 237, which creates a path from the first power source 204 through the LED 212B to ground. As such, when the processing circuitry 202 turns off the switching device 216B, the processing circuitry 202 can turn off the connection between the first power source 204 and the ground pin 219 through the LED 212B. However, because the short-to-ground connection 237 creates a path through the LED 212B to ground, the LED 212B can continue to emit light while the switching device 216B is turned off. As such, the LED 212B can be associated with a bright fault condition.

[0053] In some examples, it can be beneficial to permanently disable LED 212B to prevent LED 212B from continuing to emit light when neighboring LEDs within the matrix are turned off. Permanently disabling LED 212B can address the issue of having a light spot in a mostly turned-off LED matrix. In some examples, processing circuitry 202 can set voltage input pin 211 to zero volts (V) and allow ground pin 219 to float. In some examples, processing circuitry 202 can turn off the internal anti-leakage setting of system 200B. Processing circuitry 202 can cause second power supply 224 to deliver a forced electrical signal including a predetermined forced voltage (e.g., 4 V) to forced pin 220. In addition, processing circuitry can determine that LED 212B is associated with a bright failure condition and turn on switching device 222B, creating an electrical connection between forced pin 220 and the cathode of LED 212B. In this way, forced pin 220 applies the forced voltage to the cathode of LED 212B, permanently disabling (e.g., destroying) LED 212B without damaging LED 212A and LEDs 212C-N. In some examples, the forced voltage can be referred to as a “reverse breakdown voltage.” Alternatively or additionally, processing circuitry 202 can cause ground pin 219 to receive an electrical signal including a forced voltage and set voltage input pin 211 to 0 V. Processing circuitry 202 can turn on switching device 216B and turn off switching devices 216A and 216C-N, such that ground pin 219 delivers the forced voltage to the cathode of LED 212B without damaging LED 212A and LEDs 212C-N. Processing circuitry 202 can perform one or more techniques of the present disclosure to permanently disable one of the LEDs 112 or combinations of LEDs 112 identified by processing circuitry 202 as being associated with a bright failure condition.

[0054] Figure 2Cis a circuit diagram illustrating system 200C including a battery shorting connection 238 in accordance with one or more techniques of the present disclosure. In some examples, system 200C can be substantially identical to system 200A, except for the battery shorting connection 238 creating an electrical path from the first power source 204 around the LED 212A. As such, when the processing circuitry 202 turns on the switching device 216A, a portion of the current from the first power source 204 flowing through the switching device 216A can flow through the battery shorting connection 238, and a portion of the current flowing through the switching device 216A can flow through the LED 212A. As such, when the processing circuitry 202 turns on the switching device 216A and the switching device 216N, the LED 212N can emit more light than the LED 212A. This is because there can not be a battery shorting connection around the LED 212N, and the entire current flowing through the switching device 216N can first flow through the LED 212N. Accordingly, the LED 212A can be associated with a dim light fault condition.

[0055] In some examples, it can be beneficial to permanently disable the LED 212A in response to determining that the LED 212A is associated with a dim light fault condition. In some examples, the processing circuitry 202 can set the voltage input pin 211 to zero volts (V) and allow the ground pin 219 to float. In some examples, the processing circuitry 202 can turn off an internal anti-leakage setting of the system 200C. The processing circuitry 202 can cause the second power source 224 to deliver a forcing electrical signal including a predetermined forcing voltage (e.g., 4 V) to the forcing pin 220. Further, the processing circuitry 202 can turn on the switching device 222A creating an electrical connection between the forcing pin 220 and the cathode of the LED 212A. As such, the forcing pin 220 applies the forcing voltage to the cathode of the LED 212A, permanently disabling (e.g., destroying) the LED 212A without damaging the LEDs 212B-212N. In some embodiments, the forcing voltage can be referred to as a “reverse breakdown voltage.” Alternatively or additionally, the processing circuitry 202 can cause the ground pin 219 to receive an electrical signal including the forcing voltage and set the voltage input pin 211 to 0 V. The processing circuitry 202 can turn on the switching device 216A and turn off the switching devices 216B-216N such that the ground pin 219 delivers the forcing voltage to the cathode of the LED 212A without damaging the LEDs 212B-212N. The processing circuitry 202 can perform one or more techniques of the present disclosure to permanently disable one or a combination of the LEDs 112 identified by the processing circuitry 202 as being associated with a dim light fault condition.

[0056] Figure 2Dis a circuit diagram illustrating system 200D including weak connection 239 in accordance with one or more techniques of the present disclosure. In some examples, system 200D can be substantially identical to system 200A, except that weak connection 239 causes an increase in resistance through LED 212C as compared to one or more other LEDs of LEDs 212. As such, when processing circuitry 202 turns on switching device 216, less current can flow through LED 212C as compared to one or more other LEDs of LEDs 212 because the path through LED 212C includes more resistance than the path through the one or more other LEDs. Accordingly, LED 212C can be associated with a weak light fault condition.

[0057] In some examples, it can be beneficial to permanently disable LED 212C in response to determining that LED 212C is associated with a weak light fault condition. To disable LED 212C, processing circuitry 202 can turn off power switch 206. In some examples, processing circuitry 202 can turn off an internal anti-leakage setting of system 200D. Additionally, processing circuitry 202 can switch from a current source mode to a resistance-like mode of system 200D. In other words, processing circuitry 202 can disable LED 212C based on the resistance of the path through each respective LED of LEDs 212. In some examples, processing circuitry 202 can turn on LED 212A and increase the current through LED 212A. For example, processing circuitry 202 can apply a forced current to input pin 211, thereby permanently disabling LED 212A.

[0058] Figure 3A is a circuit diagram illustrating a high-side configuration of system 300A for testing one or more fault conditions of LEDs in accordance with one or more techniques of the present disclosure. System 300A includes LEDs 342A-342N (collectively, “LEDs 342”), LEDs 344A-344N (collectively, “LEDs 344”), LEDs 346A-346N (collectively, “LEDs 346”), switching devices 352A-352N (collectively, “switching devices 352”), switching devices 354A-354N (collectively, “switching devices 354”), switching devices 356A-356N (collectively, “switching devices 356”), a first power source 357, input pins 358A-358C (collectively, “input pins 358”), a forced pin 360, a second power source 362, a ground pin 364, a third power source 366, a switching device 368, and a short-to-ground connection 370.

[0059] System 300B can represent a high-side configuration in which switching devices 352, 354, and 356 (collectively, “switching devices 352, 354, 356”) are positioned between LEDs 342, 344, and 346 (collectively, “LEDs 342, 344, 346”) and first power supply 357. In some examples, processing circuitry (not shown in Figure 3A may determine whether each of LEDs 342, 344, 346 is associated with one or more fault conditions. For example, processing circuitry can determine that LED 342 is associated with a weak light fault condition. For example, processing circuitry can determine that the current flowing through LED 342A is less than a current threshold due to short-to-ground connection 370 based on one or more signals received by a sensing device (not shown in Figure 3A In turn, processing circuitry can permanently disable LED 342A.

[0060] To permanently disable LED 342A, processing circuitry can use third power supply 366 to set the voltage at ground pin 364 to a predetermined voltage value and allow the voltage at input pin 358 to float. Processing circuitry can turn off an internal anti-leakage setting of system 300A. In some examples, processing circuitry can cause second power supply 362 to apply a voltage of 0 V at forced pin 360. In response to determining that LED 342A is associated with a weak light fault, processing circuitry can turn on switching device 368, thereby electrically connecting ground pin 364 with forced pin 360 through LED 342A. The forced difference between ground pin 364 and forced pin 360 can permanently disable LED 342A without damaging other LEDs in LEDs 342, 344, 346. Alternatively, in some examples, processing circuitry can apply a voltage of 0 V to input pin 358 and turn on switching device 352, thereby creating an electrical connection between input pin 358A and ground pin 364. In turn, the voltage difference between input pin 358A and ground pin 364 can permanently disable LED 342A.

[0061] System 300A can include a switch matrix including a first set of switching devices 352, 354, 356, a second set of switching devices each connecting a respective LED of LEDs 342, 344, 346 with second power supply 362, and a third set of switching devices each connecting a respective LED of LEDs 342, 344, 346 with a sensing device (not shown in Figure 3Ais connected. Likewise, the switching device 368 can be one of the second set of switching devices. The third set of switching devices and the sensing device can determine the amount of current flowing through each of the LEDs 342, 344, 346. The second set of switching devices, the second power source 362, and the third power source 366 can allow the processing circuitry to disable any one or more of the LEDs 342, 344, 346.

[0062] Figure 3B is a circuit diagram illustrating a high-side configuration of another system 300B for testing one or more fault conditions of an LED according to one or more techniques of this disclosure. The system 300B can be substantially similar to the system 300A shown Figure 3A except that the system 300B includes a pair of battery short connections 372 that create a path from the input pin 358A around the switching device 352A. As such, when the processing circuitry (not shown in Figure 3B turns off the switching device 352A, current can flow through the pair of battery short connections 372 around the switching device 352A, causing the LED 342A to continue to emit light when the switching device 352A is off. As such, the switching device 352A can be associated with a bright fault condition. It can be beneficial to permanently disable the LED 342A in response to determining that the LED 342A is associated with a bright fault condition. The processing circuitry can apply one or more techniques described herein to permanently disable the LED 342A.

[0063] Figure 4A is a circuit diagram illustrating a system 400A for detecting a bright fault condition caused by a pair of ground short connections 437 according to one or more techniques of this disclosure. The system 400A includes a first power source 404, an input pin 411, LEDs 412A-412N (collectively, “LEDs 412”), switching devices 416A-416N (collectively, “switching devices 416”), internal components 418A-418N (collectively, “internal components 418”), a ground pin 419, a force pin 420, switching devices 422A-422N (collectively, “switching devices 422”), a second power source 424, a sense pin 430, switching devices 432A-432N (collectively, “switching devices 432”), and a sensing device 434.

[0064] In some examples, to detect one or more of the LEDs 412 associated with a bright fault condition, the processing circuitry (not shown in Figure 4AEach of the switching devices (not shown) in switching device 416 is configured to turn off. The processing circuitry can then select the LED in which a lighting fault condition is to be tested. For example, when the processing circuitry selects LED 412A, it can turn on switching device 432A, electrically connecting LED 412A and sensing pin 430. Thus, sensing device 434 can detect the amount of current or voltage output from LED 412A. If the amount of current and / or voltage output from LED 412A is zero or close to zero, the processing circuitry can determine that LED 412A is associated with a lighting fault condition. If the voltage output from LED 412A matches the voltage at input pin 411, the processing circuitry can determine that LED 412A is not associated with a lighting fault condition. A second power supply 424 can apply a forced voltage to permanently disable LED 412A in response to determining that LED 412A is associated with a lighting fault condition. In some examples, input pin 411 is set to a predetermined voltage (e.g., 5V). In some examples, the current flowing through an LED, regardless of the fault condition, ranges from 30 μA to 70 μA (e.g., 50 μA).

[0065] Figure 4B This is a circuit diagram illustrating a system 400B for detecting a bright fault condition caused by a short circuit connection 438 to the battery, according to one or more techniques of this disclosure. System 400B can be substantially similar to... Figure 4A The system 400A shown, except that system 400B includes a battery short-circuit connection 438, causes LED 412A to be associated with a low-light fault condition. Processing circuitry ( Figure 4B (Not shown) The association of LED 412A with a low-light fault condition can be determined based on one or more sensing signals detected by sensing device 434. In some examples, the second power supply 424 can cause a forced current to flow through LED 412A and forced pin 420, thereby permanently disabling LED 412A. In some cases, the forced current can be in the range of 50 μA to 150 μA (e.g., 100 μA).

[0066] Figure 4C This is a circuit diagram illustrating a system 400C for detecting a dark fault condition caused by a disconnection connection 441, according to one or more techniques of this disclosure. System 400C may be substantially similar to... Figure 4A The system 400A shown, except for system 400C which includes an open circuit connection 441, causes LED 412A to be associated with a dark fault condition. Processing circuitry ( Figure 4C(Not shown) The association of LED 412A with a dark fault condition can be determined based on one or more sensing signals detected by sensing device 434. In some examples, the second power supply 424 can cause a forced current to flow through LED 412A and forced pin 420, thereby permanently disabling LED 412A. In some cases, the forced current may be in the range of 10μA to 50μA (e.g., 20μA). In some examples, the forced current of system 400C may be less than the 50μA leakage current protection.

[0067] Figure 4D This is a circuit diagram illustrating a system 400D for detecting a low-light fault condition caused by a weak connection 439, according to one or more techniques of this disclosure. System 400D can be substantially similar to... Figure 4A The system 400A shown, except for system 400D which includes a weak connection 449, causes LED 412A to be associated with a low-light fault condition. Processing circuitry ( Figure 4D (Not shown) The association of LED 412A with a low-light fault condition can be determined based on one or more sensing signals detected by sensing device 434. In some examples, the second power supply 424 can cause a forced current to flow through LED 412A and forced pin 420, thereby permanently disabling LED 412A. In some cases, the forced current may be in the range of 10μA to 50μA (e.g., 20μA). In some examples, the forced current of system 400D may be less than the 50μA leakage current protection.

[0068] Figure 5 This is a flowchart illustrating example operations for identifying one or more LEDs associated with a brightness failure condition according to one or more techniques of this disclosure. (Refer to...) Figure 1 System 100 is used to describe Figure 5 .However, Figure 5 The technology can be implemented by different components of system 100 or by additional or alternative systems.

[0069] The processing circuitry 102 can control whether the LED receives the electrical signal from the first power source 104 (502). For example, the processing circuitry 102 can turn off one of the switching devices 116, turning off the connection between the first power source 104 and ground. The processing circuitry 102 can determine that the LED is associated with the bright failure condition by attempting to prevent the LED from receiving the electrical signal from the first power source 104 (504). For example, by turning off one of the switching devices 116 corresponding to the LED, the processing circuitry 102 can attempt to prevent the LED from emitting light. Subsequently, the processing circuitry disables the LED in response to detecting the bright failure condition (506). In some examples, the processing circuitry 102 disables the LED by applying a forced voltage to the cathode of the LED using the second power source 124.

[0070] The following numbered examples illustrate one or more aspects of the disclosure.

[0071] Example 1. A circuit for controlling a plurality of LEDs, the circuit comprising: a switching device, wherein the switching device is electrically connected to one of the plurality of LEDs, and wherein the switching device is configured to control whether the LED receives an electrical signal from a power source; and processing circuitry configured to: determine that the LED is associated with a bright failure condition by attempting to prevent the LED from receiving the electrical signal from the power source using the switching device; and disable the LED in response to detecting the bright failure condition.

[0072] Example 2. The circuit of example 1, wherein the switching device is one of a set of switching devices, wherein each of the set of switching devices is electrically connected to a respective LED of the plurality of LEDs, and wherein the processing circuitry is further configured to: determine that at least one other LED of the plurality of LEDs is associated with the bright failure condition by attempting to prevent the LED from receiving the electrical signal from the power source using the respective switching device of the set of switching devices; and disable the at least one other LED in response to detecting the bright failure condition.

[0073] Example 3. The circuit of examples 1-2 or any combination thereof, wherein the power source is a first power source, wherein the electrical signal is a first electrical signal, wherein the circuit further comprises a node configured to receive a second electrical signal from a second power source, and wherein to disable the LED, the processing circuitry is configured to cause the node to communicate the second electrical signal to the LED so as to permanently prevent the LED from emitting photons.

[0074] Example 4. The circuit of examples 1-3, or any combination thereof, wherein the switching device is a first switching device, wherein the circuit further comprises a second switching device electrically connected to the LED, and wherein to cause the node to communicate the second electrical signal to the LED, the processing circuitry is configured to turn on the second switching device such that the second power source communicates the second electrical signal to the LED via the node.

[0075] Example 5. The circuit of examples 1-4, or any combination thereof, wherein the cathode of the LED is electrically connected to the first switching device, wherein the cathode of the LED is electrically connected to the second switching device, and wherein to cause the node to communicate the second electrical signal to the LED, the processing circuitry is configured to cause the node to communicate the second electrical signal to the cathode of the LED, wherein the second electrical signal comprises a voltage within a range from a safe operating voltage of the LED and a breakdown voltage of the LED.

[0076] Example 6. The circuit of examples 1-5, or any combination thereof, wherein the anode of the LED is electrically connected to the first switching device, wherein the anode of the LED is electrically connected to the second switching device, and wherein to cause the node to communicate the second electrical signal to the LED, the processing circuitry is configured to cause the node to communicate the second electrical signal to the anode of the LED, wherein the second electrical signal comprises a voltage of 0 V.

[0077] Example 7. The circuit of examples 1-6, or any combination thereof, wherein the node is a first node, and wherein the circuit further comprises: a second node; and a third switching device electrically connected to the LED, and wherein, to determine that the LED is associated with a bright failure condition, the processing circuitry is configured to: turn off the first switching device; turn on the third switching device so as to communicate a third electrical signal from the LED to the second node; receive a sense signal from a sensing device electrically connected to the second node, the sense signal identifying that the LED is conductive while the first switching device is off; and determine that the LED is associated with the bright failure condition based on the sense signal.

[0078] Example 8. The circuit of examples 1-7, or any combination thereof, wherein the LED is a first LED, and wherein the processing circuitry is further configured to determine that a second LED of the plurality of LEDs is associated with a dark failure condition.

[0079] Example 9. The circuit of examples 1-8, or any combination thereof, wherein the processing circuitry is further configured to: determine that a third LED of the plurality of LEDs is associated with a dim light failure condition; and disable the third LED in response to detecting the dim light failure condition.

[0080] Example 10. The circuit of examples 1-9 or any combination thereof, wherein to determine that the third LED is associated with the weak light fault condition, the processing circuitry is configured to: identify an output voltage value corresponding to the third LED; determine whether the output voltage value corresponding to the third LED is less than a threshold output voltage value; and determine that the third LED is associated with the weak light fault condition based on the output voltage value of the third LED being less than the threshold output voltage value.

[0081] Example 11. A method for controlling a plurality of LEDs, the method comprising: controlling whether a LED of the plurality of LEDs receives an electrical signal from a power source; determining, by processing circuitry, that the LED is associated with a bright fault condition by attempting to prevent the LED from receiving the electrical signal from the power source using a switching device, wherein the switching device is electrically connected to the LED; and disabling, by the processing circuitry, the LED in response to detecting the bright fault condition.

[0082] Example 12. The method of example 11, wherein the switching device is a switching device of a set of switching devices, wherein each switching device of the set of switching devices is electrically connected to a respective LED of the plurality of LEDs, and wherein the method further comprises: determining that at least one other LED of the plurality of LEDs is associated with the bright fault condition by attempting to prevent the LED from receiving the electrical signal from the power source using a respective switching device of the set of switching devices; and disabling the at least one other LED in response to detecting the bright fault condition.

[0083] Example 13. The method of examples 11-12 or any combination thereof, wherein the power source is a first power source, wherein the electrical signal is a first electrical signal, the method further comprising: receiving, by the node, a second electrical signal from a second power source, and wherein disabling the LED comprises causing the node to transmit the second electrical signal to the LED so as to permanently prevent the LED from emitting photons.

[0084] Example 14. The method of examples 11-13 or any combination thereof, wherein the switching device is a first switching device, wherein a second switching device is electrically connected to the LED, and wherein causing the node to transmit the second electrical signal to the LED comprises turning on, by the processing circuitry, the second switching device causing the second power source to transmit the second electrical signal to the LED via the node.

[0085] Example 15. The method of examples 11-14 or any combination thereof, wherein a cathode of the LED is electrically connected to the first switching device, wherein the cathode of the LED is electrically connected to the second switching device, and wherein causing the node to transmit the second electrical signal to the LED comprises causing the node to transmit the second electrical signal to the cathode of the LED, wherein the second electrical signal comprises a voltage within a range from a safe operating voltage of the LED and a breakdown voltage of the LED.

[0086] Example 16. The method of examples 11-15, or any combination thereof, wherein the anode of the LED is electrically connected to the first switching device, wherein the anode of the LED is electrically connected to the second switching device, and wherein causing the node to deliver the second electrical signal to the LED comprises causing the node to deliver the second electrical signal to the anode of the LED, wherein the second electrical signal comprises a voltage of 0 V.

[0087] Example 17. The method of examples 11-16, or any combination thereof, wherein determining that the LED is associated with the bright failure condition comprises: turning off the first switching device; turning on the third switching device to deliver a third electrical signal from the LED to the second node, wherein the third switching device is electrically connected to the LED; receiving a sensing signal from a sensing device electrically connected to the second node, the sensing signal identifying that the LED is conductive when the first switching device is turned off; and determining that the LED is associated with the bright failure condition based on the sensing signal.

[0088] Example 18. The method of examples 11-17, or any combination thereof, wherein the LED is a first LED, and wherein the method further comprises determining, by the processing circuitry, that a second LED of the plurality of LEDs is associated with a dark failure condition.

[0089] Example 19. The method of examples 11-18, or any combination thereof, further comprising: determining, by the processing circuitry, that a third LED of the plurality of LEDs is associated with a weak light failure condition; and disabling the third LED in response to detecting the weak light failure condition.

[0090] Example 20. A system for controlling a plurality of LEDs, the circuitry comprising: a plurality of LEDs; a switching device, wherein the switching device is electrically connected to one LED of the plurality of LEDs, and wherein the switching device is configured to control whether the LED receives an electrical signal from a power source; and a processing circuitry configured to: determine that the LED is associated with a bright failure condition by attempting to prevent the LED from receiving the electrical signal from the power source using the switching device; and disable the LED in response to detecting the bright failure condition.

[0091] Various examples of the present disclosure have been described. These and other examples are within the scope of the following claims.

Claims

1. A circuit for controlling a plurality of light-emitting diodes (LEDs), the circuit comprising: A plurality of switching devices, wherein each of the plurality of switching devices is electrically connected to a corresponding individual LED among a plurality of LEDs, and wherein a corresponding switching device in a first group of the plurality of switching devices is configured to control whether the individual LED receives a first electrical signal from a first power source; The sensing device is configured to detect a current signal indicating the amount of current flowing through the single LED when a corresponding switch in the first group of switching devices is turned off and a corresponding switch in the third group of switching devices in the plurality of switching devices is turned on. as well as The processing circuit device is configured as follows: Based on the current signal from the sensing device, the individual LED is tested to determine whether the individual LED is associated with a lighting failure condition during a time window; and In response to the detection of the bright fault condition, the individual LED is disabled.

2. The circuit of claim 1, wherein the circuit further comprises a node configured to receive a second electrical signal from a second power source, and wherein, in order to disable the individual LED, the processing circuit means is configured to cause the node to transmit the second electrical signal to the individual LED to permanently prevent the individual LED from emitting photons.

3. The circuit of claim 2, wherein the circuit further comprises a corresponding switch in a second group of the plurality of switching devices electrically connected to the single LED, and wherein, in order for the node to transmit the second electrical signal to the single LED, the processing circuit means is configured to turn on the corresponding switch in the second group of switching devices, such that the second power supply transmits the second electrical signal to the single LED via the node.

4. The circuit of claim 3, wherein the cathode of the individual LED is electrically connected to a corresponding switch in the first set of switching devices, wherein the cathode of the individual LED is electrically connected to a corresponding switch in the second set of switching devices, and wherein, in order for the node to transmit the second electrical signal to the individual LED, the processing circuit means is configured to cause the node to transmit the second electrical signal to the cathode of the individual LED, wherein the second electrical signal includes a voltage within the range of the safe operating voltage of the individual LED and the breakdown voltage of the individual LED.

5. The circuit of claim 3, wherein the anode of the individual LED is electrically connected to a corresponding switch in the first set of switching devices, wherein the anode of the individual LED is electrically connected to a corresponding switch in the second set of switching devices, and wherein, in order for the node to transmit the second electrical signal to the individual LED, the processing circuit device is configured to cause the node to transmit the second electrical signal to the anode of the individual LED, wherein the second electrical signal includes a voltage of 0V.

6. The circuit of claim 3, wherein the node is a first node, and wherein the circuit further comprises a second node, and In order to determine the association between the individual LED and the brightness failure condition, the processing circuit device is configured as follows: Turn off the corresponding switching device in the first group of switching devices; Turn on the corresponding switch in the third group of switching devices so as to transmit the third electrical signal from the single LED to the second node; The sensing device electrically connected to the second node receives a sensing signal that indicates that the individual LED is conductive when the corresponding switching device in the first group of switching devices is turned off; as well as Based on the sensing signal, it is determined that the individual LED is associated with the lighting failure condition.

7. The circuit of claim 1, wherein the single LED is a first LED, and wherein the processing circuit means is further configured to determine that a second LED among the plurality of LEDs is associated with a dark fault condition.

8. The circuit of claim 7, wherein the processing circuit device is further configured to: Determine that the third LED among the plurality of LEDs is associated with a low-light fault condition; and In response to the detection of the low light fault condition, the third LED is disabled.

9. The circuit of claim 8, wherein, in order to determine that the third LED is associated with the low light fault condition, the processing circuit device is configured to: The output voltage value corresponding to the third LED is identified; Determine whether the output voltage value corresponding to the third LED is less than the threshold output voltage value; as well as Based on the fact that the output voltage value of the third LED is less than the threshold output voltage value, it is determined that the third LED is associated with a low light fault condition.

10. A method for controlling a plurality of light-emitting diodes (LEDs), the method comprising: The first set of switching devices in a plurality of switching devices controls whether a single LED in the plurality of LEDs receives a first electrical signal from a first power source, wherein each of the plurality of switching devices is electrically connected to a corresponding single LED in the plurality of LEDs. The sensing device detects a current signal indicating the amount of current flowing through the single LED when the corresponding switch in the first group of switching devices is turned off and the corresponding switch in the third group of switching devices in the plurality of switching devices is turned on. The processing circuitry uses a current signal from the sensing device to test the individual LED to determine whether the individual LED is associated with a lighting failure condition during a time window. as well as The processing circuitry disables the individual LED in response to detecting the lighting fault condition. The plurality of switching devices are all electrically connected to a corresponding individual LED among the plurality of LEDs.

11. The method according to claim 10, further comprising: The node receives a second electrical signal from a second power source, and disabling the individual LED includes: This causes the node to transmit the second electrical signal to the individual LED, thereby permanently preventing the individual LED from emitting photons.

12. The method of claim 11, wherein a corresponding switching device in the second group of switching devices of the plurality of LEDs is electrically connected to the individual LED, and wherein causing the node to transmit the second electrical signal to the individual LED comprises: The processing circuit device turns on the corresponding switch in the second group of switching devices, so that the second power supply transmits the second electrical signal to the individual LED via the node.

13. The method of claim 12, wherein the cathode of the individual LED is electrically connected to a corresponding switch in the first set of switching devices, wherein the cathode of the individual LED is electrically connected to a corresponding switch in the second set of switching devices, and wherein causing the node to transmit the second electrical signal to the individual LED comprises: The node transmits the second electrical signal to the cathode of the individual LED, wherein the second electrical signal includes a voltage within the range of the safe operating voltage and the breakdown voltage of the individual LED.

14. The method of claim 12, wherein the anode of the individual LED is electrically connected to a corresponding switch in the first set of switching devices, wherein the anode of the individual LED is electrically connected to a corresponding switch in the second set of switching devices, and wherein causing the node to transmit the second electrical signal to the individual LED comprises: The node transmits the second electrical signal to the anode of the single LED, wherein the second electrical signal includes a voltage of 0V.

15. The method of claim 12, wherein determining that the individual LED is associated with the brightness failure condition comprises: Turn off the corresponding switching device in the first group of switching devices; Turn on the corresponding switch in the third group of switching devices so as to transmit the third electrical signal from the single LED to the second node; The sensing device electrically connected to the second node receives a sensing signal that indicates that the individual LED is conductive when the corresponding switching device in the first group of switching devices is turned off; as well as Based on the sensing signal, it is determined that the individual LED is associated with a lighting failure condition.

16. The method of claim 10, wherein the single LED is a first LED, and wherein the method further comprises: The processing circuitry determines that the second LED among the plurality of LEDs is associated with a dark fault condition.

17. The method of claim 16, further comprising: The processing circuit device determines that the third LED among the plurality of LEDs is associated with a low light fault condition; as well as In response to the detection of the low light fault condition, the third LED is disabled.

18. A system for controlling a plurality of light-emitting diodes (LEDs), the system comprising: The plurality of LEDs; A plurality of switching devices, wherein each of the plurality of switching devices is electrically connected to a corresponding individual LED among a plurality of LEDs, and wherein a corresponding switching device in a first group of the plurality of switching devices is configured to control whether the individual LED receives an electrical signal from a power source; The sensing device is configured to detect a current signal indicating the amount of current flowing through the single LED when a corresponding switch in the first group of switching devices is turned off and a corresponding switch in the third group of switching devices in the plurality of switching devices is turned on. as well as The processing circuit device is configured as follows: Based on the current signal from the sensing device, the individual LED is tested to determine whether the individual LED is associated with a lighting failure condition during a time window; and In response to the detection of the bright fault condition, the individual LED is disabled.

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