Detecting shorted connections in multiple LED channels

Abstract

Embodiments of the present disclosure generally relate to detecting shorted connections in multiple LED channels. The present disclosure includes systems, methods, and techniques for detecting one or more shorted connections in multiple light emitting diode (LED) channels. For example, a circuit includes a processing circuitry configured to control a plurality of drive devices so as to cause a pair of LED channels of the plurality of LED channels to operate in a first state during a first time period and operate in a second state during a second time period. Further, 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 whether a shorted connection exists between the pair of LED channels based on the comparison of the first electrical signal and the second electrical signal.

Description

Technical Field

[0001] This disclosure relates to circuits for driving, controlling, and monitoring light-emitting diodes. Background Technology

[0002] Driver circuits are typically used to control voltage, current, or power at a load. For example, a light-emitting diode (LED) driver can control the power supplied to a string of LEDs. In some cases, an LED driver circuit can accept input signals including input current and input voltage, and deliver output signals including output current and output voltage. In some cases, the LED driver circuit can regulate at least some aspects of the input and output signals, such as controlling the output current emitted by the LED driver circuit. In some examples, a processing circuit device can control one or more driver circuits to control an array of LEDs and monitor one or more parameters associated with the array of LEDs. Summary of the Invention

[0003] Generally, this disclosure relates to devices, systems, and techniques for detecting one or more short-circuit connections in a plurality of light-emitting diode (LED) channels. For example, a short-circuit detection circuit may be configured to determine whether a pair of LED channels in a plurality of LED channels are electrically connected by a short-circuit connection. The short-circuit detection circuit may detect a short-circuit connection by performing two or more parameter measurements, including a first parameter measurement when the pair of LED channels operates in a first state; and a second parameter measurement when the pair of LED channels operates in a second state. Each of the plurality of LED channels may be controlled by a corresponding LED driver circuit of a plurality of LED driver circuits. To detect whether a short-circuit connection links a pair of LED channels, the short-circuit detection circuit may control the corresponding LED driver circuit corresponding to the pair of LED channels to operate in the first state when the short-circuit detection circuit performs the first parameter measurement, and to operate in the second state when the short-circuit detection circuit performs the second parameter measurement.

[0004] In some cases, the circuitry can control the gate driver circuitry of multiple gate driver circuits to control whether a corresponding LED channel in a plurality of LED channels is turned on or off. In some examples, the circuitry can cause each of the plurality of LED channels according to a duty cycle. As described herein, the “state” of a pair of LED channels can depend on whether the first LED channel in the pair is turned on or off and whether the second LED channel in the pair is turned on or off. Because the circuitry can control the LED channels to turn on and off according to a duty cycle, the short-circuit detection circuitry can wait until a pair of LEDs is turned on.

[0005] In some examples, the circuitry for detecting one or more short-circuit connections in a plurality of LED channels includes a processing circuitry configured to control a plurality of driving devices to cause a pair of LED channels to operate in a first state during a first time period and in a second state during a second time period. Furthermore, the processing circuitry is configured to compare a first electrical signal with a second electrical signal, the first signal corresponding to the first state of the pair of LED channels and the second signal corresponding to the second state of the pair of LED channels; and to determine, based on the comparison of the first and second electrical signals, whether a short-circuit connection exists between the pair of LED channels.

[0006] In some examples, a method for detecting one or more short-circuit connections in a plurality of LED channels includes: controlling a plurality of driving devices by a processing circuit device to cause a pair of LED channels to operate in a first state during a first time period and in a second state during a second time period. Furthermore, the method includes: comparing a first electrical signal with a second electrical signal by the processing circuit device, the first electrical signal corresponding to the first state of the pair of LED channels and the second electrical signal corresponding to the second state of the pair of LED channels; and determining, based on the comparison of the first and second electrical signals, whether a short-circuit connection exists between the pair of LED channels.

[0007] In some examples, the system includes: a plurality of LED channels; and circuitry for detecting one or more short-circuit connections among the plurality of LED channels. The circuitry includes processing circuitry configured to control a plurality of driving devices to cause a pair of LED channels to operate in a first state during a first time period and in a second state during a second time period. Furthermore, the processing circuitry is configured to compare a first electrical signal with a second electrical signal corresponding to a first state of the pair of LED channels and a second electrical signal corresponding to a second state of the pair of LED channels, and to determine, based on the comparison of the first and second electrical signals, whether a short-circuit connection exists between the pair of LED channels.

[0008] This summary is intended to provide an overview of the subject matter described herein. It is not intended to provide an exclusive or exhaustive explanation of the systems, devices, and methods detailed in the accompanying drawings and the following description. Further details of one or more examples of this disclosure are set forth in the accompanying drawings and the following description. Other features, objects, and advantages will be apparent from the specification, the drawings, and the claims. Attached Figure Description

[0009] Figure 1 This is a block diagram illustrating a system for detecting one or more short-circuit connections in a plurality of light-emitting diode (LED) channels according to one or more techniques of this disclosure.

[0010] Figures 2A-2D This is a circuit diagram illustrating a short-circuit detection circuit arrangement for performing a first example short-circuit detection test on a pair of LED channels, including a first LED channel and a second LED channel, according to one or more techniques of this disclosure.

[0011] Figures 2E-2H This is a circuit diagram illustrating a short-circuit detection circuit arrangement for performing a second example short-circuit detection test on a pair of LED channels, including a first LED channel and a second LED channel, according to one or more techniques of this disclosure.

[0012] Figures 3A-3D This is a circuit diagram illustrating a short-circuit detection circuit arrangement for performing a third example short-circuit detection test on a pair of LED channels, including a first LED channel and a second LED channel, according to one or more techniques of this disclosure.

[0013] Figures 3E-3H This is a circuit diagram illustrating a short-circuit detection circuit arrangement for performing a fourth example short-circuit detection test on a pair of LED channels, including a first LED channel and a second LED channel, according to one or more techniques of this disclosure.

[0014] Figure 4AIt is a graph showing a first curve of multiple parameters corresponding to a pair of LED channels when there is no short-circuit connection according to one or more techniques of this disclosure.

[0015] Figure 4B It is a graph showing a second curve of multiple parameters corresponding to a pair of LED channels when a short-circuit connection exists, according to one or more technologies of this disclosure.

[0016] Figure 5A This is a circuit diagram illustrating a first example circuit according to one or more technologies of the present disclosure. The first example circuit includes: a first LED channel, a second LED channel, and an analog circuit device for outputting information indicating whether a short circuit connection exists between the first LED channel and the second LED channel.

[0017] Figure 5B This is a circuit diagram illustrating a second example circuit according to one or more techniques of the present disclosure. The second example circuit includes: a first LED channel, a second LED channel, and an analog circuit device for outputting information indicating whether a short circuit connection exists between the first LED channel and the second LED channel.

[0018] Figure 6A This is a circuit diagram illustrating a third example circuit according to one or more technologies of the present disclosure. The third example circuit includes: a first LED channel, a second LED channel, and analog and digital circuitry for outputting information indicating whether a short circuit connection exists between the first LED channel and the second LED channel.

[0019] Figure 6B This is a circuit diagram illustrating a fourth example circuit according to one or more techniques of the present disclosure. The fourth example circuit includes: a first LED channel, a second LED channel, and analog and digital circuitry means for outputting information indicating whether a short circuit connection exists between the first LED channel and the second LED channel.

[0020] Figure 7 This is a flowchart illustrating an example operation of one or more techniques according to this disclosure for determining whether a short circuit connection exists between a pair of LED channels.

[0021] Throughout the specification and drawings, the same reference characters denote the same elements. Detailed Implementation

[0022] A system configured to detect one or more short circuits can control multiple driving devices, each of which controls whether a corresponding light-emitting diode (LED) channel in a plurality of LED channels receives an electrical signal from a power source. In some examples, the system's circuitry can control multiple LED channels to perform one or more short-circuit detection measurements. For example, to perform a short-circuit detection measurement, the system can control a pair of LED channels to determine whether a short-circuit connection links the pair. The circuitry can compare one or more parameters corresponding to the pair of LED channels when they operate in a first state with one or more parameters corresponding to the pair when they operate in a second state. Based on this comparison, the circuitry can determine whether the pair of LED channels is linked by a short-circuit connection. In some examples, when the multiple LED channels are undergoing normal operation, the system can perform a test on each pair of adjacent LED channels in the plurality of LED channels.

[0023] Figure 1 This is a block diagram illustrating a system 10 for detecting one or more short-circuit connections in a plurality of LED channels 16 according to one or more techniques of this disclosure. Figure 1 As shown in the example, system 10 includes a power supply 12, circuitry 14, and multiple LED channels 16. Circuitry 14 includes multiple driver circuits 22A-22N (collectively referred to as “driver circuits 22”), advanced control circuitry 28, multiple driver control units 30A-30N (collectively referred to as “driver control units 30”), and short-circuit detection circuitry 36. Each driver circuit in driver circuit 22 includes a corresponding driver device among multiple driver devices and a corresponding amplifier among multiple amplifiers. For example, driver circuit 22A includes driver device 24A and amplifier 26A. The corresponding driver devices and corresponding amplifiers corresponding to each driver circuit in driver circuits 22B-22N are arranged in a configuration similar to that of driver device 24A and amplifier 26A. Each driver control unit in driver control unit 30 includes a corresponding PWM engine among multiple pulse width modulation (PWM) engines and a driver control unit among multiple driver control units. For example, driver control unit 30A includes PWM engine 32A and driver control unit 34A.

[0024] System 10 represents a system for controlling multiple LED channels 16 to operate according to a lighting scheme. For example, the lighting scheme can determine whether each LED channel 16 is turned on or off and control the duty cycle of each LED channel 16. When the multiple LED channels 16 are operated according to the lighting scheme, system 10 can identify one or more short-circuit connections among the multiple LED channels 16. In some examples, the system identifies one or more short-circuit connections without changing the lighting scheme, but this is not mandatory. Circuit 14 can make one or more changes to the operation of the LED channels 16 to identify one or more short-circuit connections.

[0025] Power source 12 is configured to deliver operating power to circuit 14 and supply power to multiple LED channels 16. In some examples, power source 12 includes a battery and generation circuitry to generate operating power. In some examples, power source 12 is rechargeable to allow for extended operation. Power source 12 may include any one or more of several different battery types, such as nickel-cadmium and lithium-ion batteries. In some examples, the maximum voltage output of power source 12 is approximately 12V. In some examples, power source 12 provides power in the range from 10 watts (W) to 15W. In some examples, power source 12 represents a power source other than a battery.

[0026] As described above, circuit 14 includes: driver circuitry 22, advanced control circuitry device 28, driver control unit 30, and short-circuit detection circuitry device 36. In some examples, any one or a combination of the advanced control circuitry device 28, driver control unit 30, and short-circuit detection circuitry device 36 may represent a "processing circuitry device" that includes one or more processors configured to implement functions and / or processing instructions for execution within system 10. For example, the processing circuitry device may be able to process instructions stored in memory (not shown in FIG. 1). For example, the processing circuitry device may include: a microprocessor, digital signal processor (DSP), application-specific integrated circuit (ASIC), field-programmable gate array (FPGA), or equivalent discrete logic circuitry device or integrated logic circuitry device, or any combination of the foregoing devices or circuitry devices. Therefore, the processing circuitry device may include any suitable structure, whether in hardware, software, firmware, or any combination thereof, to perform the functions attributed herein to system 10.

[0027] In some examples, the memory communicating with the processing circuitry includes computer-readable instructions that, when executed by the processing circuitry, cause system 10 to perform various functions attributed to this system 10. The memory may include any volatile, non-volatile, magnetic, optical, or electrical medium, such as random access memory (RAM), read-only memory (ROM), non-volatile RAM (NVRAM), electrically erasable programmable ROM (EEPROM), flash memory, or any other digital medium.

[0028] Each driver circuit in driver circuit 22 is configured to control whether a corresponding LED channel in LED channel 16 is turned on or off. That is, driver circuit 22A controls LED channel 16A, driver circuit 22B controls LED channel 16B, and so on. This means that processing circuitry (e.g., advanced control circuitry 28, driver control unit 30, short-circuit detection circuitry 36, or any combination thereof) can be configured to control driver circuit 22 to independently control whether each LED channel in LED channel 16 is turned on or off. However, short-circuit connections in multiple LED channels 16 can affect how the processing circuitry controls the multiple LED channels 16. In this way, it may be beneficial for system 10 to detect one or more short-circuit connections in multiple LED channels 16 so that any existing short-circuit connections can be repaired or resolved in the control of LED channels 16. Although system 10 includes driver circuitry 22 in a “low-side” configuration, where each driver circuit in driver circuitry 22 is connected to the output of a corresponding LED channel in multiple LED channels 16, in some cases (in Figure 1 (Not shown in the image), one or more techniques described herein can be implemented using circuitry that controls multiple driver circuits in a "high-side" configuration to control multiple LED channels. In the high-side configuration, the driver circuitry can be electrically connected to the input of an LED channel controlled by the driver circuitry, allowing current to flow from the power supply to the LED channel through the driver circuitry. In the low-side configuration, the driver circuitry can be electrically connected to the output of an LED channel controlled by the driver circuitry, allowing current to flow from the power supply to the driver circuitry through the LED channel.

[0029] like Figure 1As shown, the driver circuit 22A includes a driver device 24A. In some cases, the driver device 24A may include a power switch, such as, but not limited to, any type of field-effect transistor (FET), including any transistor or combination of metal-oxide-semiconductor field-effect transistors (MOSFETs), bipolar junction transistors (BJTs), insulated-gate bipolar transistors (IGBTs), junction field-effect transistors (JFETs), high electron mobility transistors (HEMTs), or other types of elements controlled by voltage or current. Furthermore, the driver device 24A may include any one or a combination of n-type transistors, p-type transistors, and power transistors. In some examples, the driver device 24A includes vertical transistors, lateral transistors, and / or horizontal transistors. In some examples, the driver device 24A includes other analog devices (such as diodes and / or thyristors). In some examples, the driver device 24A may function as a switch and / or as an analog device.

[0030] In some examples, driver device 24A includes three terminals: two load terminals and a control terminal. When driver device 24A represents a MOSFET, driver device 24A may include a drain terminal, a source terminal, and at least one gate terminal, wherein the control terminal is the gate terminal. When driver device 24A represents a BJT switch, the control terminal may represent the base terminal. Current may flow between the two load terminals of driver device 24A based on the voltage at the respective control terminal. Therefore, current may flow through driver device 24A based on a control signal delivered to the control terminal of driver device 24A. In one example, driver device 24A may be activated to allow driver device 24A to conduct if the voltage applied to the control terminal of driver device 24A is greater than or equal to a voltage threshold. Furthermore, driver device 24A may be deactivated to prevent driver device 24A from conducting when the voltage applied to the control terminal of driver device 24A is lower than the threshold voltage. Processing circuitry (e.g., advanced control circuitry 28, driver control unit 30A, short-circuit detection circuitry 36, or any combination thereof) can be configured to control driver device 24A such that driver device 24A is turned on or off at a point in time.

[0031] The driver device 24A may comprise 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 may experience lower switching power losses. Improvements in magnetism and faster switching (such as gallium nitride switches) may allow the driver device 24A to draw short bursts of current. Compared to low-frequency devices, these high-frequency devices may require more precise timing to send control signals (e.g., voltage signals delivered to the control terminals of the driver device 24A).

[0032] The driver circuit 22A includes an amplifier 26A. For example... Figure 1 As shown, amplifier 26A receives a first input electrical signal from driver control unit 30A and a second input electrical signal from LED channel 16A. Amplifier 26A generates an output electrical signal based on the first and second input electrical signals for delivery to the control terminal of driver device 24A. Therefore, the output electrical signal generated by amplifier 26A controls whether driver device 24A is turned on (e.g., "closed") or turned off (e.g., "open"). When the output electrical signal generated by amplifier 26A turns on driver device 24A, current can flow from power supply 12 through LED channel 16A and through driver device 24A. That is, when driver device 24A is turned on, LED channel 16A is turned on. When the output electrical signal generated by amplifier 26A turns off driver device 24A, in some cases, driver device 24A can prevent or attenuate the current flowing through LED channel 16A. That is, when driver device 24A is turned off, LED channel 16A is turned off.

[0033] Advanced control circuitry 28 and / or driver control unit 30 can control driver circuit 22 to control whether each LED channel in LED channel 16 is turned on or off, and to control the duty cycle of each LED channel in LED channel 16. For example, driver control unit 30A includes PWM engine 32A, which receives one or more instructions from advanced control circuitry 28. PWM engine 32A determines the duty cycle for LED channel 16A based on one or more instructions. Based on the duty cycle determined by PWM engine 32A, driver control unit 34A can be configured to control drive unit 24A to turn on and off according to the duty cycle, thus causing LED channel 16A to turn on or off according to the duty cycle. Each driver control unit 30 in driver control units 30A-30N controls a corresponding driver circuit in driver circuits 22A-22N. That is, driver control unit 30A controls driver circuit 22A, driver control unit 30B controls driver circuit 22B, and so on.

[0034] For example, driver device 24A can cycle between on and off with a duty cycle and frequency. As used herein, the term "duty cycle" refers to the ratio of the amount of time a driver device is on to the amount of time a driver device is off, and the term "frequency" refers to the number of switching cycles completed per unit time. A complete switching cycle can include a complete "on" phase and a complete "off" phase of the driver device. For example, when driver device 24A cycles between off and on at a frequency of 1 kHz and a duty cycle of 0.9, the driver device can perform 1000 switching cycles per second, where the duration of the "on" phase of the driver device is nine times that of the "off" phase of the driver device. Driver device 24A can operate according to any duty cycle from 0.0 to 1.0. When driver 24A operates with a duty cycle of 1.0 (meaning driver 24A is continuously switched on), the processing circuitry of circuit 14 can control driver 24A to briefly switch off driver 24A in order to perform one or more short-circuit detection techniques described herein. When driver 24A operates with a duty cycle of 0.0 (meaning driver 24A is continuously switched off), the processing circuitry of circuit 14 can control driver 24A to briefly switch on driver 24A in order to perform one or more short-circuit detection techniques described herein.

[0035] The short-circuit detection circuit device 36 can be configured to perform one or more short-circuit detection tests to identify one or more short-circuit connections in a plurality of LED channels. For example, to perform a short-circuit detection test on a pair of LED channels including LED channel 16A and LED channel 16B (collectively referred to as "LED channels 16A, 16B"), processing circuitry (e.g., advanced control circuitry 28, driver control unit 30, short-circuit detection circuitry 26, or any combination thereof) can control multiple driving devices so that LED channels 16A, 16B operate in a first state during a first time period and in a second state during a second time period. The short-circuit detection circuitry 36 can compare a first electrical signal corresponding to the first state of LED channels 16A, 16B with a second electrical signal corresponding to the second state of LED channels 16A, 16B.

[0036] For example, when a pair of LED channels 16A and 16B operate in a first state, the short-circuit detection circuit device 36 can receive a first electrical signal. Furthermore, when the pair of LED channels 16A and 16B operate in a second state, the short-circuit detection circuit device 36 can receive a second electrical signal. To compare the first and second electrical signals, the short-circuit detection circuit device 36 can determine the difference between the first and second electrical signals. Subsequently, the short-circuit detection circuit device 36 can determine whether a short circuit exists between the pair of LED channels 16A and 16B based on the comparison of the first and second electrical signals. To determine whether a short circuit exists between the pair of LED channels 16A and 16B, the short-circuit detection circuit device 36 is configured to compare the difference between the first and second electrical signals with a threshold difference, and determine whether a short circuit exists based on the comparison of the determined difference and the threshold difference.

[0037] In one example, when a pair of LED channels 16A and 16B operate in a first state, a first electrical signal received by the short-circuit detection circuit device 36 represents the output of LED channel 16B, and when the pair of LED channels 16A and 16B operate in a second state, a second electrical signal received by the short-circuit detection circuit device 36 represents the output of LED channel 16B. In this way, when the pair of LED channels 16A and 16B operate in the first and second states respectively, the first and second electrical signals can represent the direct electrical output of the second LED channel 16B. Therefore, in this example, the comparison of the first and second electrical signals represents a comparison of the outputs of one or more LED channels 16B independent of the outputs of power supply 12. However, this is not necessary.

[0038] In another example, the first electrical signal received by the short-circuit detection circuit device 36 represents the difference between the output of LED channel 16B and the output of power supply 12, which is configured to supply power to multiple LED channels 16 when a pair of LED channels 16A, 16B operate in a first state. Furthermore, the second electrical signal received by the short-circuit detection circuit device 36 represents the difference between the output of LED channel 16B and the output of power supply 12, which is configured to supply power to multiple LED channels 16 when a pair of LED channels 16A, 16B operate in a second state. That is, the first and second electrical signals can represent the difference between the output of LED channel 16B and the output of power supply 12, rather than representing the direct output of LED channel 16B. When determining whether a short circuit exists between a pair of LED channels 16A, 16B, the difference between the output of LED channel 16B and the output of power supply 12 represented by the first and second electrical signals may be beneficial, so that the short-circuit detection circuit device 36 does not attribute the difference between the first and second electrical signals caused by an unstable power supply 12 to a non-existent short circuit.

[0039] As described herein, the "state" of a pair of LED channels can be determined by the on / off state of each LED channel in the corresponding pair. In the case of LED channels 16A and 16B, the state of a pair of LED channels 16A and 16B can be operated according to one of four states: LED channel 16A is off and LED channel 16B is off; LED channel 16A is off and LED channel 16B is on; LED channel 16A is on and LED channel 16B is on; and LED channel 16A is on and LED channel 16B is off. A corresponding pair of LED channels in a plurality of LED channels 16 can be operated according to one or more of these four states. That is, a pair of LED channels including LED channel 16B and LED channel 16C (collectively referred to as "LED channels 16B, 16C") can operate according to the same four states (e.g., LED channel 16B is off and LED channel 16C is off, LED channel 16B is off and LED channel 16C is closed, LED channel 16B is closed and LED channel 16C is closed, and LED channel 16B is closed and LED channel 16C is off).

[0040] In some examples, to determine whether a short circuit exists between a pair of LED channels 16A and 16B, the processing circuitry of circuit 14 can control the pair of LED channels 16A and 16B to operate in a first state by controlling LED channel 16A to turn off and LED channel 16B to turn off. When the pair of LED channels 16A and 16B are operating in the first state, the short circuit detection circuitry 36 can receive a first electrical signal. Subsequently, the processing circuitry of circuit 14 can control the pair of LED channels 16A and 16B to operate in a second state by controlling LED channel 16A to turn on and LED channel 16B to turn off. When the pair of LED channels 16A and 16B are operating in the second state, the short circuit detection circuitry 36 can receive a second electrical signal. To determine whether a short circuit exists between the pair of LED channels 16A and 16B, the short circuit detection circuitry 36 can determine that a short circuit exists when the difference between the first electrical signal and the second electrical signal is greater than a threshold difference. In some cases, when the difference between the first electrical signal and the second electrical signal is not greater than the threshold difference, the short-circuit detection circuit device 36 can determine that there is no short-circuit connection between a pair of LED channels 16A and 16B.

[0041] Alternatively or additionally, to determine whether a short circuit exists between a pair of LED channels 16A and 16B, the processing circuitry of circuit 14 can control the pair of LED channels 16A and 16B to operate in a first state by controlling LED channel 16A to turn on and LED channel 16B to turn off. When the pair of LED channels 16A and 16B are operating in the first state, the short circuit detection circuitry 36 can receive a first electrical signal. Subsequently, the processing circuitry of circuit 14 can control the pair of LED channels 16A and 16B to operate in a second state by controlling LED channel 16A to turn on and LED channel 16B to turn on. When the pair of LED channels 16A and 16B are operating in the second state, the short circuit detection circuitry 36 can receive a second electrical signal. To determine whether a short circuit exists between the pair of LED channels 16A and 16B, the short circuit detection circuitry 36 can determine that a short circuit exists when the difference between the first electrical signal and the second electrical signal is not greater than a threshold difference. When the difference between the first electrical signal and the second electrical signal is greater than the threshold difference, the short circuit detection circuit device 36 can determine that there is no short circuit connection.

[0042] In this way, circuit 14 can perform more than one different test to determine whether a short circuit exists between a pair of LED channels. For example, a first state may represent one of four possible states of a pair of LED channels 16A, 16B, and a second state may represent another of the four possible states. Short circuit detection circuitry 36 collects a first electrical signal and a second electrical signal to determine, if any, how one or more parameters of a pair of LED channels 16A, 16B change when the states of the pair of LED channels 16A, 16B change. Therefore, the determined response of a pair of LED channels 16A, 16B to a state change reveals whether a short circuit exists. In some examples, circuit 14 may test for a short circuit in a pair of LED channels 16B, 16C after testing for a short circuit in a pair of LED channels 16A, 16B. In some examples, circuit 14 may use a similar technique to test for a pair of LED channels 16B, 16C, but this is not necessary.

[0043] like Figure 1 As shown, multiple LED channels 16 are arranged sequentially. In some examples, the short-circuit detection circuit 36 ​​can determine whether a short circuit exists between any adjacent pair of LED channels within the multiple LED channels 16. That is, the short-circuit detection circuit 36 ​​can determine whether a short circuit exists between LED channels 16A and 16B, the short-circuit detection circuit 36 ​​can determine whether a short circuit exists between LED channels 16B and 16C, and the short-circuit detection circuit 36 ​​can determine whether a short circuit exists between LED channels 16C and 16D. Figure 1 (not shown in the image), and so on. In some examples, the short-circuit detection circuit 36 ​​tests each pair of adjacent LED channels within the plurality of LED channels 16, but this is not necessary. The short-circuit detection circuit 36 ​​can test any pair or more pairs of adjacent LED channels. The techniques described herein with respect to a pair of adjacent LED channels 16A, 16B can be performed with respect to any pair of adjacent LEDs within the plurality of LED channels 16.

[0044] Each LED channel in LED channel 16 may include one or more LEDs. LED channel 16 may include any one or more suitable semiconductor light sources. In some examples, the LEDs of LED channel 16 may include pn junctions configured to emit light when activated. In some examples, LED channel 16 may be included in a headlight assembly for automotive applications. For example, LED channel 16 may illuminate the road in front of a vehicle. As used herein, a vehicle may refer to a motorcycle, truck, boat, golf cart, snowmobile, heavy machinery, or any type of vehicle using directional lighting. In some examples, LED channel 16 may include a first set of LEDs representing high beam (HB) LEDs and a second set of LEDs representing low beam (LB) LEDs. In some cases, circuit 14 may activate LB LEDs, activate HB LEDs, activate a set of LB LEDs and HB LEDs, or deactivate both LB LEDs and HB LEDs. LED channel 16 may include any number of LED channels, and each LED channel may include any number of LEDs. In some examples, LED channel 16 may include multiple LED channels in the range of 2 to 1000 LED channels. In some examples, LED channel 16 may include multiple LEDs ranging from 1 LED to 100 LEDs. In some examples, LED channel 16 may include multiple LEDs ranging from 2 LED channels to 32 LED channels. In some examples, LED channel 16 may include multiple LEDs ranging from 1 LED to 50 LEDs.

[0045] Figures 2A-2D This is a circuit diagram illustrating a short-circuit detection circuit device 36 according to one or more techniques of this disclosure performing a first example short-circuit detection test on a pair of LED channels, including a first LED channel 42 and a second LED channel 44. Figures 2A-2D As shown, the first LED channel 42 is connected to the first pin 46, and the second LED channel 44 is electrically connected to the second pin 48. The short-circuit detection circuit 36 ​​is configured to receive one or more electrical signals output from the second LED channel 44, wherein LED channels 42 and 44 receive power from the power supply 12. In some examples, when the short-circuit connection does not link the first LED channel 42 and the second LED channel 44, Figures 2A-2D The circuit can be configured to operate according to a first mode 52 and a second mode 54, and when the first LED channel 42 and the second LED channel 44 are short-circuited, Figures 2A-2DThe circuit can be configured to operate according to the third mode 56 and the fourth mode 58. In some examples, a pair of LED channels including the first LED channel 42 and the second LED channel 44 (collectively referred to as "LED channels 42, 44") can be any pair of adjacent LED channels of the plurality of LED channels 16. Although in some cases ( Figures 2A-2D A configuration (not shown) for controlling the first LED channel 42 and the second LED channel 44 with a low-side driving device is illustrated. Figure 2A - Figure 2D The circuitry can be modified, but one or more techniques described herein can be applied via circuitry that includes a high-side configured driving device.

[0046] In some examples, processing circuit devices (e.g., Figure 1 The advanced control circuitry 28, the driver control unit 30, and the short-circuit detection circuitry 36 (any circuit or combination thereof) can control a pair of LED channels 42, 44 to operate in a first state. In some examples, to control the pair of LED channels 42, 44 to operate in the first state, the processing circuitry controls the first LED channel 42 to turn off and the processing circuitry controls the second LED channel 44 to turn off. When the pair of LED channels 42, 44 are operating in the first state, the short-circuit detection circuitry 36 can receive a first electrical signal, where the first electrical signal represents the output of the second LED channel 44. Subsequently, the processing circuitry can control the pair of LED channels 42, 44 to operate in a second state. In some examples, to control the pair of LED channels 42, 44 to operate in the second state, the processing circuitry controls the first LED channel 42 to turn on and the processing circuitry controls the second LED channel 44 to turn off. When the pair of LED channels 42, 44 are operating in the second state, the short-circuit detection circuitry 36 can receive a second electrical signal, where the second electrical signal represents the output of the second LED channel 44.

[0047] When the processing circuit device controls the first LED channel 42 to turn off and the second LED channel 44 to turn off (for example, controlling LED channels 42 and 44 to operate in the first state), and when there is no short circuit connection between the first LED channel 42 and the second LED channel 44, Figures 2A-2DThe circuit operates according to a first mode 52. When operating according to the first mode 52, the current flowing through the first LED channel 42 can represent a first current amplitude (I1), and the current flowing through the second LED channel 44 can also represent a first current amplitude (I1). In some examples, I1 can be in the range of 2 microamps (μA) to 10 μA (e.g., 5 μA). Thus, even when the first LED channel 42 and the second LED channel 44 are “turned off,” a small non-zero current I1 can flow through both the first LED channel 42 and the second LED channel 44. This small non-zero current may be referred to herein as “leakage current.” Furthermore, when the circuit operates according to the first mode 52, the voltage across the first LED channel 42 can represent a first voltage amplitude (V1), and the voltage across the second LED channel 44 can also represent a first voltage amplitude (V1). In some examples, the first voltage amplitude V1 can be 1.43 volts (V) for each LED in the respective LED channel, but this is not required. The first voltage amplitude V1 can represent any voltage amplitude.

[0048] When the processing circuit device controls the first LED channel 42 to turn on and controls the second LED channel 44 to turn off (e.g., controls LED channels 42 and 44 to operate in a second state), and when there is no short circuit connection between the first LED channel 42 and the second LED channel 44, Figures 2A-2D The circuit operates according to the second mode 54. When the short-circuit detection circuit device 36 performs a short-circuit detection test on a pair of LED channels 42, 44, the circuit can switch from the first mode 52 to the second mode 54. When operating according to the second mode 54, the current flowing through the first LED channel 42 can represent a second current amplitude (I2), and the current flowing through the second LED channel 44 can represent a first current amplitude (I1). In some examples, I2 can be in the range of 2 mA to 1000 mA (e.g., 5 mA). Thus, I2 is significantly greater than the leakage current I1. Furthermore, when the circuit operates according to the second mode 54, the voltage across the first LED channel 42 can represent a first voltage amplitude (V2), and the voltage across the second LED channel 44 can represent a first voltage amplitude (V1). In some examples, the second voltage amplitude V2 can be 1.74 volts (V) for each LED in the corresponding LED channel, but this is not required. The second voltage amplitude V2 can represent any voltage amplitude. In some examples, V2 can be greater than V1.

[0049] When there is no short circuit connection between the first LED channel 42 and the second LED channel 44, and when both the first LED channel 42 and the second LED channel 44 are off, the short circuit detection circuit device 36 can receive a first electrical signal from the second LED channel 44. When the first LED channel 42 is on and the second LED channel 44 is off, the short circuit detection circuit device 36 can receive a second electrical signal from the second LED channel 44. The short circuit detection circuit device 36 can compare the first and second electrical signals to determine whether the voltage across the second LED channel 44 has changed beyond a threshold value in response to the change from the first state to the second state of the LED channels 42 and 44. Since the voltage across the second LED channel 44 when the second state of the LED channels 42 and 44 is operating in the first state is the same as the voltage across the second LED channel 44 when the second state of the LED channels 42 and 44 is operating in the second state (both are V1), when the circuit mode changes from the first mode 52 to the second mode 54, the short circuit detection circuit device 36 can determine that there is no short circuit detection between the first LED channel 42 and the second LED channel 44.

[0050] When a short circuit does exist between the first LED channel 42 and the second LED channel 44, the short circuit detection circuit device 36 can detect a change in the voltage across the second LED channel 44 in response to the LED channels 42 and 44 transitioning from a first state shown in the third mode 56 of the circuit to a second state shown in the fourth mode 58 of the circuit. For example, when the processing circuit device controls the LED channels 42 and 44 to operate in the third state and a short circuit exists between the first LED channel 42 and the second LED channel 44, Figures 2A-2D The circuit operates according to the third mode 56. When operating according to the third mode 56, the current flowing through the first LED channel 42 can represent the first current amplitude (I1), and the current flowing through the second LED channel 44 can represent the leakage current I1. Therefore, when the circuit operates according to the third mode 56, the voltage across the first LED channel 42 can represent the first voltage amplitude (V1), and the voltage across the second LED channel 44 can represent the first voltage amplitude (V1).

[0051] When the processing circuit controls LED channels 42 and 44 to operate in the second state, and when there is a short circuit connection between the first LED channel 42 and the second LED channel 44, Figure 2A - Figure 2DThe circuit operates according to mode 58. When operating according to mode 58, the current flowing through the first LED channel 42 can represent a third current amplitude (I3), and the current flowing through the second LED channel 44 can also represent a third current amplitude (I3). In some examples, I3 can be in the range of 1mA to 1000mA (e.g., 2.5mA). Thus, I3 is significantly greater than the leakage current I1, and I3 is less than I2. This is likely due to the fact that when the first LED channel 42 is turned on and the second LED channel 44 is turned off and a short circuit connects LED channels 42 and 44, even when the second LED channel 44 is turned off, it means that some current flowing through the first LED channel 42 will leak through the short circuit connected to the second LED channel 44. Furthermore, when the circuit operates according to mode 58, the voltage across the first LED channel 42 can represent a third voltage amplitude (V3), and the voltage across the second LED channel 44 can also represent a third voltage amplitude (V3). In some examples, the third voltage amplitude V3 may be 1.71 volts (V) for each LED in the corresponding LED channel, but this is not required. The third voltage amplitude V3 can represent any voltage amplitude.

[0052] When the short-circuit detection circuit 36 ​​compares the first electrical signal with the second electrical signal and determines that the voltage across the second LED channel 44 increases from V1 to V3, the short-circuit detection circuit 36 ​​can determine that a short circuit exists between the first LED channel 42 and the second LED channel 44. That is, the short-circuit detection circuit 36 ​​can determine that the difference between V1 and V3 is greater than a threshold voltage difference, and therefore the short-circuit detection circuit 36 ​​can determine that a short circuit exists between the first LED channel 42 and the second LED channel 44. Thus, when no short circuit exists, Figure 2A and Figure 2B Modes 52 and 54 respectively illustrate the circuit's response to a transition from operating according to a first state to operating according to a second state for LED channels 42 and 44. When a short-circuit connection links the channels, Figure 2C and Figure 2D Modes 52 and 58 respectively show the circuit's response to the transition from LED channels 42 and 44 operating according to the first state to operating according to the second state.

[0053] Figures 2E-2H This is a circuit diagram illustrating a short-circuit detection circuit device 36 according to one or more techniques of this disclosure performing a second example short-circuit detection test on a pair of LED channels, including a first LED channel 42 and a second LED channel 44. Figures 2E-2HAs shown, the first LED channel 42 is electrically connected to the first pin 46, and the second LED channel 44 is electrically connected to the second pin 48. Figures 2E-2H The circuit can be with Figures 2A-2D The circuits are basically the same, except that... Figures 2E-2H In the circuit, the short-circuit detection circuit device 36 receives the output from the power supply 12 and the output from the second LED channel 44, while Figures 2A-2D In this circuit, the short-circuit detection circuit 36 ​​receives the output from the second LED channel 44, but not the output from the power supply 12. Although in some cases ( Figure 2E (Not shown in Figure 2H) A configuration is shown in which the first LED channel 42 and the second LED channel 44 are controlled by a low-side driving device. Figures 2E-2H However, one or more techniques described herein can be applied via circuitry that includes driving devices configured on the high side.

[0054] In some examples, processing circuit devices (e.g., Figure 1 The advanced control circuitry 28, the drive control unit 30, and the short-circuit detection circuitry 36 (any circuit or combination thereof) can control a pair of LED channels 42, 44 to operate in a first state. In some examples, to control the pair of LED channels 42, 44 to operate in the first state, the processing circuitry controls the first LED channel 42 to turn off, and the processing circuitry controls the second LED channel 44 to turn off. When the pair of LED channels 42, 44 are operating in the first state, the short-circuit detection circuitry 36 can receive a first electrical signal, wherein the first electrical signal represents the difference between the output of the second LED channel 44 and the output of the power supply 12. Subsequently, the processing circuitry can control the pair of LED channels 42, 44 to operate in a second state. In some examples, to control the pair of LED channels 42, 44 to operate in the first state, the processing circuitry controls the first LED channel 42 to turn on and the processing circuitry controls the second LED channel 44 to turn off. When the pair of LED channels 42, 44 are operating in the second state, the short-circuit detection circuitry 36 can receive a second electrical signal, wherein the second electrical signal represents the difference between the output of the second LED channel 44 and the output of the power supply 12.

[0055] When a pair of LED channels 42 and 44 switch from operating in the first state to operating in the second state, and when there is no short circuit connection between the pair of LED channels 42 and 44... Figure 2E - Figure 2HThe circuit switches from operating according to mode 52 to operating according to mode 54. Alternatively, when a short circuit exists between a pair of LED channels 42, 44, when the pair of LED channels 42, 44 switches from operating in the first state to operating in the second state, Figures 2E-2H The circuit switches from operating according to mode 56 to operating according to mode 58.

[0056] The short-circuit detection circuit 36 ​​can determine whether a short-circuit connection has occurred by comparing a first electrical signal with a second electrical signal. Figures 2E-2H In the example, when a pair of LED channels 42, 44 operate in a first state (e.g., the first LED channel 42 is off and the second LED channel 44 is off), a first electrical signal represents the difference between the voltage output from power supply 12 and the voltage output from the second LED channel 44. When the pair of LED channels 42, 44 operate in a second state (e.g., the first LED channel 42 is on and the second LED channel 44 is off), a second electrical signal represents the difference between the voltage output from power supply 12 and the voltage output from the second LED channel 44. The short-circuit detection circuit device 36 can determine the difference between the first voltage indicated by the first electrical signal and the second voltage indicated by the second electrical signal. When the difference between the first voltage and the second voltage is greater than a threshold voltage difference, thereby indicating a transition of the circuit from mode 56 to mode 58, the short-circuit detection circuit device 36 can determine that a short circuit exists between the pair of LED channels 42, 44. When the difference between the first voltage and the second voltage is not greater than the threshold voltage difference, the circuit is switched from mode 52 to mode 54, and the short circuit detection circuit device 36 can determine that there is no short circuit connection between the pair of LED channels 42 and 44.

[0057] Figures 3A-3D This is a circuit diagram illustrating a short-circuit detection circuit device 36 according to one or more techniques of this disclosure performing a third example short-circuit detection test on a pair of LED channels including a first LED channel 42 and a second LED channel 44. Figures 3A-3D As shown, the first LED channel 42 is connected to the first pin 46 and the second LED channel 44 is electrically connected to the second pin 48. The short-circuit detection circuit 36 ​​is configured to receive one or more electrical signals output from the second LED channel 44, wherein LED channels 42 and 44 receive power from the power supply 12. In some examples, when the short-circuit connection does not link the first LED channel 42 and the second LED channel 44, Figures 3A-3D The circuit can be configured to operate according to a first mode 62 and a second mode 64, and when a short-circuit connection links the first LED channel 42 and the second LED channel 44, Figures 2A-2DThe circuit can be configured to operate according to the third mode 66 and the fourth mode 58. In some examples, a pair of LED channels including the first LED channel 42 and the second LED channel 44 (collectively referred to as "LED channels 42, 44") can be any pair of adjacent LED channels of the plurality of LED channels 16. In some cases ( Figures 3A-3D (Not shown in the image), although the configuration of controlling the first LED channel 42 and the second LED channel 44 with low-side driving devices is shown. Figures 3A-3D However, one or more techniques described herein can be applied via circuitry that includes driving devices configured on the high side.

[0058] Figures 3A-3D The third example of short-circuit detection test can be compared with Figures 2A-2D The first example of the short-circuit detection test for the circuit is basically the same, except that... Figures 3A-3D The third example of short-circuit detection testing includes the transition of LED channels 42 and 44 from a first state to a second state. In the first state, the first LED channel 42 is turned on and the second LED channel 44 is turned off. In the second state, the first LED channel 42 is turned on and the second LED channel 44 is turned on. Figures 2A-2D The first example short-circuit detection test includes the transition of LED channels 42 and 44 from a first state to a second state, in which the first LED channel 42 is off and the second LED channel 44 is off, and in the second state, the first LED channel 42 is on and the second LED channel 44 is off.

[0059] For example, the short-circuit detection circuit device 36 can perform a third example short-circuit detection test by comparing a first electrical signal with a second electrical signal, wherein the first electrical signal represents the output of the second LED channel 44 when the first LED channel 42 is on and the second LED channel 44 is off, and the second electrical signal represents the output of the second LED channel 44 when the first LED channel 42 is on and the second LED channel 44 is on. The short-circuit detection circuit device 36 can determine the difference between the voltage of the first electrical signal and the voltage of the second electrical signal.

[0060] When the difference between the voltage of the first electrical signal and the voltage of the second electrical signal is greater than the threshold voltage difference, the short-circuit detection circuit device 36 can determine that there is no short-circuit connection between LED channels 42 and 44. This is because when the second LED channel 44 switches from off to on, it is expected that the voltage output from the second LED channel 44 will at least exceed the voltage difference threshold when there is no short-circuit connection. For example, in the circuit transition from mode 62 to mode 64, the voltage output from the second LED channel 44 changes from V1 in mode 62 to V2 in mode 64. In some cases, the difference between V1 and V2 is greater than the voltage difference threshold.

[0061] Alternatively, the short-circuit detection circuit 36 ​​can determine that a short circuit exists between LED channels 42 and 44 when the difference between the voltages of the first and second electrical signals is not greater than a threshold voltage difference. This is because when the second LED channel 44 switches from off to on, if a short circuit exists, a portion of the current flowing through the second LED channel 44 may leak to the first LED channel 42 through the short circuit, thus attenuating the change in the voltage output from the second LED channel 44 when the LED channel 44 is on. For example, in the circuit transition from mode 66 to mode 68, the voltage output from the second LED channel 44 changes from V1 in mode 66 to V3 in mode 68. In some cases, the difference between V1 and V3 is not greater than a voltage difference threshold that indicates a short circuit exists between LED channels 42 and 44.

[0062] Figures 3E-3H This is a circuit diagram illustrating a short-circuit detection circuit device 36 performing a fourth example short-circuit detection test on a pair of LED channels, including a first LED channel 42 and a second LED channel 44, according to one or more techniques of this disclosure. Figures 3E-3H As shown, the first LED channel 42 is electrically connected to the first pin 46, and the second LED channel 44 is electrically connected to the second pin 48. Figures 3E-3H The circuit can be with Figures 3A-3D The circuits are basically the same, except that... Figures 3E-3H In the circuit, the short-circuit detection circuit device 36 receives the output from the power supply 12 and the output from the second LED channel 44, while Figures 3A-3D In the example, the short-circuit detection circuit 36 ​​receives the output from the second LED channel 44 but not the output from the power supply 12. Although in some cases (Figure 3E- Figure 3H A configuration (not shown) of controlling the first LED channel 42 and the second LED channel 44 with low-side driving devices is illustrated. Figures 3E-3HHowever, one or more techniques described herein can be applied via circuitry that includes driving devices configured on the high side.

[0063] Figures 3E-3H The fourth example short-circuit detection test includes a transition from a first state to a second state, in which LED channels 42 and 44 are switched on and off respectively, and in the second state, both LED channels 42 and 44 are switched on. For example, the short-circuit detection circuit device 36 can perform the fourth example short-circuit detection test by comparing a first electrical signal with a second electrical signal. When the first LED channel 42 is switched on and the second LED channel is switched off, the first electrical signal represents the difference between the output of the second LED channel 44 and the output of the power supply 12. When the first LED channel 42 is switched on and the second LED channel is switched on, the second electrical signal represents the difference between the output of the second LED channel 44 and the output of the power supply 12. The short-circuit detection circuit device 36 can determine the difference between the voltage of the first electrical signal and the voltage of the second electrical signal.

[0064] When the difference between the voltage of the first electrical signal and the voltage of the second electrical signal is greater than the threshold voltage difference, the short-circuit detection circuit device 36 can determine that there is no short-circuit connection between LED channels 42 and 44. This is because when the second LED channel 44 switches from off to on, it is expected that, in the absence of a short-circuit connection, the difference between the voltage output from the second LED channel 44 and the voltage output from the power supply 12 will at least exceed the voltage difference threshold. For example, in the circuit transition from mode 62 to mode 64, the voltage output from the second LED channel 44 changes from V1 in mode 62 to V2 in mode 64. In some cases, the difference between V1 and V2 is greater than the voltage difference threshold.

[0065] Alternatively, when the difference between the voltage of the first electrical signal and the voltage of the second electrical signal is not greater than a threshold voltage difference, the short-circuit detection circuit device 36 can determine that a short circuit exists between LED channels 42 and 44. This is because when the second LED channel 44 switches from off to on, if a short circuit exists, a portion of the current flowing through the second LED channel 44 may leak to the first LED channel 42 through the short circuit. Therefore, when LED channel 44 is on, the change in the difference between the voltage output from the second LED channel 44 and the voltage output from the power supply 12 is attenuated. For example, in the circuit transition from mode 66 to mode 68, the difference between the voltage output from the second LED channel 44 and the voltage output from the power supply 12 changes from V1 in mode 66 to V3 in mode 68. In some cases, the difference between V1 and V3 is not greater than a voltage difference threshold, which indicates that a short circuit exists between LED channels 42 and 44.

[0066] Figure 4A This is a graph showing a first curve 70 of multiple parameters corresponding to a pair of LED channels when no short-circuit connection is present, according to one or more techniques of this disclosure. The pair of LED channels can represent... Figure 1 Any pair of LED channels among multiple LED channels. When there is no short circuit between a pair of LED channels, time 72 indicates the point in curve 70 where the pair of LED channels transitions from a first state to a second state. In some examples, the first curve 70 of Figure 4A corresponds to Figures 2A-2B The circuit operation is such that there is no short-circuit connection between the first LED channel 42 and the second LED channel 44.

[0067] Curve 70 includes the voltage output 73 of the first LED channel and the voltage output 74 of the second LED channel in the pair of LED channels. As shown in Figure 4, when the pair of LED channels transitions from a first state to a second state at time 72, the voltage output 74 of the second LED channel remains at a first voltage level 75A. In the example of Figure 4, the first state represents the state where the first LED channel is off and the second LED channel is off, and the second state represents the state where the first LED channel is on and the second LED channel is off. During the transition of the pair of LED channels from the first state to the second state, the second LED channel remains off. This means that when there is no short circuit connection between the first LED channel and the second LED channel, it is expected that the voltage output of the second LED channel will remain constant during the transition from the first state to the second state. Therefore, as shown by curve 70, the voltage output 74 of the second LED channel indicates that there is no short circuit connection between the pair of LED channels.

[0068] Figure 4B This is a graph of a second curve 71 showing multiple parameters corresponding to a pair of LED channels when a short-circuit connection exists, according to one or more techniques of this disclosure. A pair of LED channels can represent... Figure 4A Curve 70 corresponds to a pair of LED channels among the plurality of LED channels 16. Time 76 indicates the point in curve 71 where the pair of LED channels transitions from a first state to a second state when a short circuit exists between them. In some examples, Figure 4B The first curve 71 corresponds to Figures 2C-2D The circuit operation, wherein there is a short circuit connection between the first LED channel 42 and the second LED channel 44.

[0069] Curve 71 includes the voltage output 77 of the first LED channel in a pair of LED channels and the voltage output 74 of the second LED channel in the pair. As shown by curve 71, when the pair of LED channels transitions from the first state to the second state at time 76, the voltage output 78 of the second LED channel transitions from the first voltage level 79A to the second voltage level 77B. In the example of Figure 4, the first state represents the state where the first LED channel is off and the second LED channel is off, and the second state represents the state where the first LED channel is on and the second LED channel is off. During the transition of the pair of LED channels from the first state to the second state, when the first LED channel transitions from off to on, the second LED channel remains off. This means that when there is a short circuit connection between the first LED channel and the second LED channel, the voltage output of the second LED channel is expected to change during the transition from the first state to the second state because a portion of the current flowing through the first LED channel leaks through the short circuit connection to the second LED channel. Therefore, as shown by curve 71, the voltage output 78 of the second LED channel indicates a short circuit connection between the pair of LED channels because the transition of the voltage output 78 from the first voltage level 79A to the second voltage level 79B is greater than the voltage difference threshold.

[0070] Figure 5A This is a circuit diagram illustrating a first example circuit 80 according to one or more techniques of the present disclosure. The first example circuit 80 includes a first LED channel 82, a second LED channel 84, and an analog circuit device for outputting information indicating whether a short circuit exists between the first LED channel 82 and the second LED channel 84. Figure 5A As shown, the first LED channel 82 is connected to the first pin 86, and the second LED channel 84 is electrically connected to the second pin 88. The first LED channel 82 and the second LED channel 84 can receive power from the power supply 12. In some cases, a multiplexer 90, a switching device 98, a capacitor 100, a threshold voltage element 102, and an amplifier 104 may be represented. Figure 1 The components of the short-circuit detection circuit device 36.

[0071] Multiplexer 90 includes a first multiplexer data input 92A and a second multiplexer data input 92B (collectively referred to as "multiplexer data input 92"). Furthermore, multiplexer 90 includes a multiplexer data output 94 and a multiplexer control input 96. For example... Figure 5AAs shown, the first multiplexer input 92A is electrically connected to the output of the first LED channel 82, and the second multiplexer input 92B is electrically connected to the output of the second LED channel 84. The multiplexer 90 can control whether an electrical signal flows from the first multiplexer data input 92A through the multiplexer 90 to the multiplexer data output 94, or whether an electrical signal flows from the second multiplexer data input 92B through the multiplexer 90 to the multiplexer data output 94, based on a control signal received at the multiplexer control input 96.

[0072] For example, during a test to determine whether a short circuit exists between the first LED channel 82 and the second LED channel 84, the multiplexer 90 can receive a control signal at the multiplexer control input 96, which causes the multiplexer 90 to carry an electrical signal from the second multiplexer data input 92B to the multiplexer data output 94. That is, the multiplexer 90 carries an electrical signal from the second multiplexer data input 92B from the second multiplexer data input 92B to the multiplexer data output 94. For example, when the first LED channel 82 and the second LED channel 84 are operating in a first state, the multiplexer 90 can receive a first electrical signal, and when the first LED channel 82 and the second LED channel 84 are operating in a second state, the multiplexer 90 can receive a second electrical signal. When the multiplexer 90 receives the first electrical signal from the second LED channel 84, the switching device 98 can be turned on, charging the capacitor 100. In some cases, the capacitor 100 can be charged to the voltage level of the first electrical signal. When the multiplexer 90 receives the second electrical signal, the switching device 98 can be turned off, allowing the second electrical signal to travel directly to the amplifier 104 without passing through the channel including the capacitor 100.

[0073] Amplifier 104 includes a first amplifier data input 106A and a second amplifier data input 106B (collectively referred to as "amplifier data input 106") and an amplifier data output 108. When multiplexer 90 receives a second electrical signal, the second electrical signal travels from multiplexer data output 94 to the first amplifier data input 106A. Additionally, capacitor 100 discharges, passing through threshold voltage element 102 to the second amplifier data input 106B.

[0074] As described above, when the switching device 98 is activated and when the multiplexer 90 receives the first electrical signal, the capacitor 100 charges to the voltage value of the first electrical signal. When the capacitor 100 discharges, it emits an electrical signal that includes the voltage of the first electrical signal. The electrical signal emitted by the capacitor 100 passes through the threshold voltage element 102, thereby generating a third electrical signal whose voltage is equal to the sum of the voltage of the first electrical signal and the voltage of the threshold voltage element 102. The first amplifier data input 106A receives the second electrical signal, and the second amplifier data input 106B receives the third electrical signal. The amplifier 104 can generate an amplifier signal indicating whether the voltage of the third electrical signal is greater than the voltage of the second electrical signal.

[0075] Since the voltage of the third electrical signal represents the sum of the voltage differences between the first electrical signal and the threshold voltage, amplifier 104 can output an amplifier signal via amplifier data output 108, wherein the amplifier signal indicates whether the difference between the voltage of the first electrical signal and the voltage of the second electrical signal is greater than the threshold voltage difference. The processing circuitry can determine, based on the amplifier signal, whether a short circuit exists between the first LED channel 82 and the second LED channel 84, and whether this short circuit indicates whether the voltage difference is greater than the threshold voltage difference.

[0076] Figure 5B This is a circuit diagram illustrating a second example circuit 81 according to one or more techniques of this disclosure. The second example circuit 81 includes a first LED channel 82, a second LED channel 84, and an analog circuit device for outputting information indicating whether a short circuit exists between the first LED channel 82 and the second LED channel 84. Figure 5A As shown, the first LED channel 82 is connected to the first pin 86, and the second LED channel 84 is electrically connected to the second pin 88. The first LED channel 82 and the second LED channel 84 can receive power from the power supply 12. In some cases, a multiplexer 90, a switching device 98, a capacitor 100, a threshold voltage element 102, an amplifier 104, and an amplifier 110 may be represented. Figure 1 The components of the short-circuit detection circuit device 36.

[0077] Figure 5B The circuit 81 can be connected with Figure 5AThe circuit 80 is essentially the same as that of the multiplexer 90, except that circuit 81 includes an amplifier 110, which receives electrical signals output from power supply 12 and from multiplexer 90. For example, amplifier 110 includes a first amplifier data input 112A and a second amplifier data input 112B (collectively referred to as "amplifier data input 112") and an amplifier data output 114. Amplifier 110 receives the output from power supply 12 at the first amplifier data input 112A and receives the output from multiplexer 90 at the second amplifier data input 112B. Amplifier 110 can generate an amplifier signal representing the difference between the signal received at the first amplifier data input 112A and the signal received at the second amplifier data input 112B.

[0078] Circuit 81 can be connected with Figure 5A Circuit 80 operates substantially the same as circuit 81, except that a first electrical signal generated by amplifier 110 of circuit 81 represents the difference between the voltage of the electrical signal output by power supply 12 and the voltage of the electrical signal output by second LED channel 84 when first LED channel 82 and second LED channel 84 operate in the first state, and a second electrical signal generated by amplifier 110 of circuit 81 represents the difference between the voltage of the electrical signal output by power supply 12 and the voltage of the electrical signal output by second LED channel 84 when first LED channel 82 and second LED channel 84 operate in the second state. By generating the first and second electrical signals to account for the output of power supply 12, amplifier 110 can prevent circuit 81 from erroneously indicating the presence of a short circuit due to fluctuations in the power output of power supply 12.

[0079] Figure 6A This is a circuit diagram illustrating a third example circuit 83 according to one or more techniques of the present disclosure. The third example circuit 83 includes: a first LED channel 82, a second LED channel 84, and analog and digital circuitry for outputting information indicating whether a short circuit exists between the first LED channel 82 and the second LED channel 84. Figure 6A As shown, the first LED channel 82 is connected to the first pin 86, and the second LED channel 84 is electrically connected to the second pin 88. Both the first LED channel 82 and the second LED channel 84 can receive power from the power supply 12. In some cases, a multiplexer 120, an analog-to-digital converter (ADC) 132, a finite state machine (FSM) 134, a multiplexer (MUX) 136, a register 144, a summing element 152, and an amplifier 154 can be represented. Figure 1 The components of the short-circuit detection circuit device 36.

[0080] Multiplexer 120 includes a first multiplexer data input 122A and a second multiplexer data input 122B (collectively referred to as "multiplexer data input 122"). Additionally, multiplexer 122 includes a multiplexer data output 124 and a multiplexer control input 126. Figure 6A As shown, the first multiplexer data input 122A is electrically connected to the output of the first LED channel 82, and the second multiplexer data input 122B is electrically connected to the output of the second LED channel 84. The multiplexer 120 can control whether an electrical signal passes from the first multiplexer data input 122A through the multiplexer 120 to the multiplexer data output 124, or whether an electrical signal passes from the second multiplexer data input 122B through the multiplexer 120 to the multiplexer data output 124, based on a control signal received at the multiplexer control input 126.

[0081] During the test to determine whether a short circuit exists between the first LED channel 82 and the second LED channel 84, the multiplexer 120 may receive a control signal at the multiplexer control input 126, which causes the multiplexer 120 to carry electrical signals from the second multiplexer data input 122B to the multiplexer data output 124. That is, the multiplexer 120 carries electrical signals from the second multiplexer data input 122B to the multiplexer data output 124. For example, when the first LED channel 82 and the second LED channel 84 are operating in a first state, the multiplexer 120 may receive a first electrical signal, and when the first LED channel 82 and the second LED channel 84 are operating in a second state, the multiplexer 120 may receive a second electrical signal.

[0082] ADC 132 can receive one or more analog electrical signals from multiplexer 120 and convert them into one or more digital signals. FSM 134 can output one or more control signals to multiplexer 120, multiplexer 136, or other components. Multiplexer 136 includes multiplexer 139 and a first multiplexer output 140A and a second multiplexer output 140B (collectively referred to as "multiplexer 140"). Register 144 can receive and store one or more digital signals from multiplexer 136. For example, a first electrical signal received from second LED channel 84 can be stored in sampling and memory 148, and a second electrical signal received from second LED channel 84 can be stored in output register 150. Amplifier 154 includes a first amplifier data input 156A, a second amplifier data input 156B, and an amplifier data output 158. Amplifier 154 compares a first signal representing the sum of the voltage differences between a first electrical signal and a threshold voltage with a second signal representing the voltage of a second electrical signal. Amplifier 154 can output an amplifier signal indicating whether the difference between the voltage of the first electrical signal and the voltage of the second electrical signal is greater than the threshold voltage difference, which in turn indicates whether there is a short circuit connection between the first LED channel 82 and the second LED channel 84.

[0083] Figure 6B This is a circuit diagram illustrating a fourth example circuit 85 according to one or more techniques of this disclosure. The fourth example circuit 85 includes: a first LED channel 82, a second LED channel 84, and analog and digital circuitry for outputting information indicating whether a short circuit exists between the first LED channel 82 and the second LED channel 84. Figure 6A As shown, the first LED channel 82 is connected to the first pin 86, and the second LED channel 84 is electrically connected to the second pin 88. The first LED channel 82 and the second LED channel 84 can receive power from the power supply 12. In some cases, a multiplexer 120, an analog-to-digital converter (ADC) 132, a finite state machine (FSM) 134, a multiplexer 136, a register 144, a summing element 152, and an amplifier 154 can be represented. Figure 1 The components of the short-circuit detection circuit device 36.

[0084] Figure 6B The circuit 85 can be connected with Figure 6ACircuit 85 is essentially the same as circuit 83, except that circuit 85 includes the connection between the output of power supply 12 and the input 128 of ADC 132. Multiplexer 120 is connected to ADC 132 via ADC input 130. In some examples, circuit 85 operates essentially the same as circuit 83 when determining whether the first LED channel 82 and the second LED channel 84 include a short-circuit connection, except that circuit 85 takes the output of power supply 12 into account.

[0085] Figure 7 This is a flowchart illustrating an example operation for determining whether a short-circuit connection exists between a pair of LED channels, according to one or more techniques of this disclosure. Regarding... Figure 1 System 10 Description Figure 7 However, it can be performed by different components of system 10 or by additional or alternative systems. Figure 7 The technology.

[0086] Circuit 14 can control multiple driving devices to operate a pair of LED channels among the multiple LED channels 16 in a first state (702). In some examples, each of the multiple driving devices may be part of a corresponding driver circuit in a plurality of driver circuits. Each of the multiple driving devices can control whether a corresponding LED channel among the multiple LED channels 16 is turned on or off. To enable a pair of driving devices to operate in the first state, circuit 14 can control a first driving device and a second driving device to control the first LED channel and the second LED channel respectively. When a pair of LED channels is operating in the first state, short-circuit detection circuit device 36 can receive a first electrical signal (704). In some examples, short-circuit detection circuit device 36 receives the first electrical signal from a second LED channel of the pair of LED channels, and the first electrical signal indicates the voltage output from the second LED channel. In some examples, short-circuit detection circuit device 36 receives the first electrical signal from an amplifier that generates the first electrical signal to indicate the difference between the voltage output from the second LED channel and the voltage output from power supply 12.

[0087] Subsequently, circuit 14 can control multiple driving devices to operate a pair of LED channels in the second state (706). To operate the pair of driving devices in the second state, circuit 14 can control a first driving device and a second driving device to control the first LED channel and the second LED channel respectively. When the pair of LED channels are operating in the second state, short-circuit detection circuit device 36 can receive a second electrical signal (708). In some examples, short-circuit detection circuit device 36 receives a second electrical signal from the second LED channel of the pair of LED channels, and the second electrical signal indicates the voltage output from the second LED channel. In some examples, short-circuit detection circuit device 36 receives a second electrical signal from an amplifier that generates a second electrical signal to indicate the difference between the voltage output from the second LED channel and the voltage output from power supply 12. Short-circuit detection circuit device 36 can compare the first electrical signal with the second electrical signal (710). Based on this comparison, short-circuit detection circuit device 36 can determine whether a short circuit exists between the pair of LED channels (712).

[0088] The techniques described in this disclosure may be implemented, at least in part, in hardware, software, firmware, or any combination thereof. For example, aspects of the described techniques may be implemented within one or more processors, including one or more microprocessors, DSPs, ASICs, FPGAs, or any other equivalent integrated or discrete logic circuit devices, and any combination of these components. The terms "processor" or "processor circuit device" may generally refer to any of the aforementioned logic circuit devices, either alone or in combination with other logic circuit devices or any other equivalent circuit devices. A control unit, including hardware, may also perform one or more of the techniques of this disclosure.

[0089] Such hardware, software, and firmware can be implemented within the same device or in separate devices to support the various technologies described in this disclosure. Furthermore, any of the described units, modules, or components can be implemented together or separately as discrete but interoperable logical devices. Describing different features as modules or units is intended to highlight different functional aspects and does not necessarily imply that such modules or units must be implemented via separate hardware, firmware, or software components. Rather, the functions associated with one or more modules or units can be performed via separate hardware, firmware, or software components, or the functions can be integrated into common or separate hardware, firmware, or software components.

[0090] The following numbered examples illustrate one or more aspects of this disclosure.

[0091] Example 1. A circuit for detecting one or more short-circuit connections in a plurality of light-emitting diode (LED) channels, wherein the circuit includes processing circuit means configured to: control a plurality of driving devices to cause a pair of LED channels in the plurality of LED channels to operate in a first state during a first time period and in a second state during a second time period; compare a first electrical signal with a second electrical signal, the first electrical signal corresponding to the first state of the pair of LED channels and the second electrical signal corresponding to the second state of the pair of LED channels; and determine whether a short-circuit connection exists between the pair of LED channels based on the comparison of the first electrical signal and the second electrical signal.

[0092] Example 2. According to the circuit of Example 1, a pair of LED channels includes a first LED channel and a second LED channel, and the processing circuit device is further configured to: receive a first electrical signal when the pair of LED channels operate in a first state; and receive a second electrical signal when the pair of LED channels operate in a second state, wherein, in order to compare the first electrical signal and the second electrical signal, the processing circuit device is configured to determine the difference between the first electrical signal and the second electrical signal, and wherein, in order to determine whether a short circuit connection exists, the processing circuit device is configured to: compare the difference between the first electrical signal and the second electrical signal with a threshold difference; and determine whether a short circuit connection exists based on the comparison between the difference and the threshold difference.

[0093] Example 3. According to the circuit of Example 2, when a pair of LED channels are operating in a first state, a first electrical signal represents the output of the second LED channel, and when a pair of LED channels are operating in a second state, a second electrical signal represents the output of the second LED channel and the output of the power supply.

[0094] Example 4. A circuit according to any one of Examples 2 to 3, wherein when a pair of LED channels operate in a first state, a first electrical signal represents the difference between the output of the second LED channel and the output of a power supply, the power supply being configured to provide power to a plurality of LED channels, and wherein when a pair of LED channels operate in a second state, a second electrical signal represents the difference between the output of the second LED channel and the output of the power supply.

[0095] Example 5. A circuit according to any one of Examples 2 to 4, wherein, in order to control a plurality of driving devices to operate a pair of LED channels in a first state, the processing circuit device is configured to: control a first LED channel of the pair of LED channels to turn off; and control a second LED channel of the pair of LED channels to turn off, wherein, in order to control a plurality of driving devices to operate a pair of LED channels in a second state, the processing circuit device is configured to: control the first LED channel of the pair of LED channels to turn on; and control the second LED channel of the pair of LED channels to turn off, and wherein, in order to determine whether a short circuit connection exists based on a comparison of a difference with a threshold difference, the processing circuit device is configured to: determine that a short circuit connection exists when the difference is greater than the threshold difference; and determine that no short circuit connection exists when the difference is not greater than the threshold difference.

[0096] Example 6. A circuit according to any one of Examples 2 to 5, wherein, in order to control a plurality of driving devices to operate a pair of LED channels in a first state, the processing circuit device is configured to: control a first LED channel of the pair of LED channels to turn on; and control a second LED channel of the pair of LED channels to turn off, wherein, in order to control a plurality of driving devices to operate a pair of LED channels in a second state, the processing circuit device is configured to: control the first LED channel of the pair of LED channels to turn on; and control the second LED channel of the pair of LED channels to turn on, and wherein, in order to determine whether a short circuit connection exists based on a comparison of a difference and a threshold difference, the processing circuit device is configured to: determine that no short circuit connection exists when the difference is greater than the threshold difference; and determine that a short circuit connection exists when the difference is not greater than the threshold difference.

[0097] Example 7. A circuit according to any one of Examples 2 to 6, wherein the processing circuit means includes: a capacitor configured to receive a first electrical signal from a second LED channel of a pair of LED channels; and an amplifier configured to: receive a second electrical signal from the output of the second LED channel of the pair of LED channels; receive a third electrical signal representing the sum of the difference between the first electrical signal output from the capacitor and a threshold value; and generate an amplifier signal based on the second and third electrical signals, the amplifier signal indicating whether a short circuit connection exists between the pair of LED channels.

[0098] Example 8. A circuit according to any one of Examples 2 to 7, wherein the processing circuit means includes: an analog-to-digital converter (ADC) configured to: convert a first electrical signal into a first digital signal; and convert a second electrical signal into a second digital signal; and an amplifier configured to: receive the second digital signal from the ADC; receive a third digital signal representing the sum of a threshold difference and the first digital signal output from the ADC; and generate an amplifier signal based on the second digital signal and the third digital signal, the amplifier signal indicating whether a short circuit connection exists between a pair of LED channels.

[0099] Example 9. A circuit according to any one of Examples 1 to 8, wherein a plurality of LED channels are arranged in a sequence of LED channels, and wherein a pair of LED channels represents an adjacent pair of LED channels within the sequence of LED channels.

[0100] Example 10. A circuit according to any one of Examples 1 to 9, wherein a pair of LED channels is a first pair of LED channels, wherein a short-circuit connection is a first short-circuit connection, and wherein the processing circuit device is further configured to: control a plurality of driving devices to cause a second pair of LED channels among the plurality of LED channels to operate in a first state during a third time period and in a second state during a fourth time period; compare a third electrical signal with a fourth electrical signal, the third electrical signal being a third electrical signal corresponding to the first state of a pair of LED channels, and the fourth electrical signal being a third electrical signal corresponding to the second state of a pair of LED channels; and determine whether a second short-circuit connection exists between the second pair of LED channels based on the comparison of the third electrical signal and the fourth electrical signal.

[0101] Example 11. A circuit according to any one of Examples 1 to 10, wherein a plurality of LED channels are arranged in a sequence of LED channels, wherein a first pair of LED channels represents a first pair of adjacent LED channels within the sequence of LED channels, wherein a second pair of LED channels represents a second pair of adjacent LED channels within the sequence of LED channels, wherein the first pair of adjacent LED channels includes a first LED channel and a second LED channel, and wherein the second pair of adjacent LED channels includes a second LED channel and a third LED channel.

[0102] Example 12. The circuit according to any one of Examples 1 to 11 further includes: a plurality of driving devices, wherein each of the plurality of driving devices controls whether a corresponding LED channel of the plurality of LED channels is turned on or off, wherein when the processing circuit device controls the driving device of the plurality of driving devices to turn on the LED channel of the plurality of LED channels, the amplitude of the current output from the LED channel is in the range of 2 mA to 1000 mA, and wherein when the processing circuit device controls the driving device of the plurality of driving devices to turn off the LED channel of the plurality of LED channels, the amplitude of the current output from the LED channel is in the range of 2 μA to 10 μA.

[0103] Example 13. A circuit according to any of Examples 1 to 12, wherein each of the plurality of LED channels includes one or more LEDs.

[0104] Example 14. A circuit according to any one of Examples 1 to 13, wherein each of a plurality of LED channels includes one or more LEDs, and wherein one or more of the plurality of LED channels includes two or more LEDs.

[0105] Example 15. A method for detecting one or more short-circuit connections in a plurality of light-emitting diode (LED) channels, the method comprising: controlling a plurality of driving devices by a processing circuit means to cause a pair of LED channels in the plurality of LED channels to operate in a first state during a first time period and in a second state during a second time period; comparing a first electrical signal and a second electrical signal by the processing circuit means, the first electrical signal corresponding to the first state of the pair of LED channels and the second electrical signal corresponding to the second state of the pair of LED channels; and determining, by the processing circuit means, whether a short-circuit connection exists between the pair of LED channels based on the comparison of the first electrical signal and the second electrical signal.

[0106] 16. The method of Example 15, wherein a pair of LED channels includes a first LED channel and a second LED channel, and wherein the method further includes: receiving a first electrical signal when the pair of LED channels operate in a first state; and receiving a second electrical signal when the pair of LED channels operate in a second state, wherein comparing the first electrical signal and the second electrical signal includes determining a difference between the first electrical signal and the second electrical signal, and wherein determining whether a short-circuit connection exists includes: comparing the difference between the first electrical signal and the second electrical signal with a threshold difference; and determining whether a short-circuit connection exists based on the comparison of the difference with the threshold difference.

[0107] Example 17. According to the method of Example 16, controlling a plurality of driving devices to operate a pair of LED channels in a first state includes: controlling a first LED channel in the pair of LED channels to turn off; and controlling a second LED channel in the pair of LED channels to turn off, wherein controlling a plurality of driving devices to operate a pair of LED channels in a second state includes: controlling the first LED channel in the pair of LED channels to turn on; and controlling the second LED channel in the pair of LED channels to turn off, and wherein determining whether a short-circuit connection exists based on a comparison of a difference with a threshold difference includes: determining that a short-circuit connection exists when the difference is greater than the threshold difference; and determining that a short-circuit connection does not exist when the difference is not greater than the threshold difference.

[0108] Example 18. A method according to any one of Examples 16 to 17, wherein controlling a plurality of driving devices to operate a pair of LED channels in a first state includes: controlling a first LED channel of the pair of LED channels to turn on; and controlling a second LED channel of the pair of LED channels to turn off, wherein controlling a plurality of driving devices to operate a pair of LED channels in a second state includes: controlling the first LED channel of the pair of LED channels to turn on; and controlling the second LED channel of the pair of LED channels to turn on, and wherein determining whether a short circuit connection exists based on a comparison of a difference with a threshold difference includes: determining that no short circuit connection exists when the difference is greater than the threshold difference; and determining that a short circuit connection exists when the difference is not greater than the threshold difference.

[0109] Example 19. The method according to any one of Examples 16 to 18 further includes: receiving a first electrical signal from a second LED channel of a pair of LED channels by a capacitor; receiving a second electrical signal from the output of the second LED channel of the pair of LED channels by an amplifier; receiving a third electrical signal by the amplifier, the third electrical signal representing the sum of a threshold difference and the first electrical signal output from the capacitor; and generating an amplifier signal by the amplifier based on the second electrical signal and the third electrical signal, the amplifier signal indicating whether a short circuit connection exists between the pair of LED channels.

[0110] Example 20. The method according to any one of Examples 16 to 19 further includes: converting a first electrical signal into a first digital signal by an analog-to-digital converter (ADC); converting a second electrical signal into a second digital signal by the ADC; receiving the second digital signal from the ADC by an amplifier; receiving a third digital signal by the amplifier, the third digital signal representing the sum of a threshold difference and the first digital signal output from the ADC; and generating an amplifier signal by the amplifier based on the second digital signal and the third digital signal, the amplifier signal indicating whether a short circuit connection exists between a pair of LED channels.

[0111] Example 21. A method according to any one of Examples 16 to 20, wherein a pair of LED channels is a first pair of LED channels, wherein a short-circuit connection is a first short-circuit connection, and wherein the method further comprises: controlling a plurality of driving devices by a processing circuit device to cause a second pair of LED channels among the plurality of LED channels to operate in a first state during a third time period and in a second state during a fourth time period; comparing a third electrical signal and a fourth electrical signal by the processing circuit device, the third electrical signal corresponding to the first state of a pair of LED channels and the fourth electrical signal corresponding to the second state of a pair of LED channels; and determining, based on the comparison of the third electrical signal and the fourth electrical signal, whether a second short-circuit connection exists between the second pair of LED channels.

[0112] Example 22. A system comprising: a plurality of light-emitting diode (LED) channels; and circuitry for detecting one or more short-circuit connections among the plurality of LED channels, wherein the circuitry includes processing circuitry means configured to: control a plurality of driving devices to cause a pair of LED channels among the plurality of LED channels to operate in a first state during a first time period and in a second state during a second time period; compare a first electrical signal and a second electrical signal, the first electrical signal corresponding to the first state of the pair of LED channels and the second electrical signal corresponding to the second state of the pair of LED channels; and determine whether a short-circuit connection exists between the pair of LED channels based on the comparison of the first electrical signal and the second electrical signal.

[0113] Various examples of this disclosure have been described. These and other examples are within the scope of the appended claims.

Claims

1. A circuit for detecting one or more short-circuit connections in a plurality of light-emitting diode (LED) channels, wherein the circuit includes a processing circuit device configured to: Control multiple driving devices to enable a pair of LED channels among the multiple LED channels to operate in a first state during a first time period and in a second state during a second time period; Compare the first electrical signal with the second electrical signal, wherein the first electrical signal corresponds to the first state of the pair of LED channels, and the second electrical signal corresponds to the second state of the pair of LED channels; and The presence of a short circuit between the pair of LED channels is determined by comparing the first electrical signal with the second electrical signal. The state of a pair of LED channels is determined by the on / off state of each LED channel in the corresponding LED channel.

2. The circuit of claim 1, wherein the pair of LED channels includes a first LED channel and a second LED channel, and wherein the processing circuit device is further configured to: The first electrical signal is received when the pair of LED channels are operating in the first state; and The second electrical signal is received when the pair of LED channels are operating in the second state. In order to compare the first electrical signal and the second electrical signal, the processing circuit device is configured to determine the difference between the first electrical signal and the second electrical signal, and In order to determine whether the short-circuit connection exists, the processing circuit device is configured as follows: The difference between the first electrical signal and the second electrical signal is compared with a threshold difference; and The existence of the short-circuit connection is determined based on the comparison between the difference and the threshold difference.

3. The circuit according to claim 2, When the pair of LED channels operate in the first state, the first electrical signal represents the output of the second LED channel, and When the pair of LED channels are operating in the second state, the second electrical signal represents the output of the second LED channel and the output of the power supply.

4. The circuit according to claim 2, When the pair of LED channels operates in the first state, the first electrical signal represents the difference between the output of the second LED channel and the output of the power supply, the power supply being configured to provide power to the plurality of LED channels. When the pair of LED channels are operating in the second state, the second electrical signal represents the difference between the output of the second LED channel and the output of the power supply.

5. The circuit according to claim 2, In order to control the plurality of driving devices so that the pair of LED channels operate in the first state, the processing circuit device is configured as follows: Control the first LED channel of the pair of LED channels to turn off; and Turn off the second LED channel in the pair of LED channels. In order to control the plurality of driving devices so that the pair of LED channels operate in the second state, the processing circuit device is configured as follows: Control the first LED channel of the pair of LED channels to turn on; and Control the second LED channel of the pair of LED channels to turn off, and In order to determine whether the short-circuit connection exists based on the comparison between the difference and the threshold difference, the processing circuit device is configured to: When the difference is greater than the threshold difference, it is determined that the short-circuit connection exists; and When the difference is not greater than the threshold difference, it is determined that there is no short-circuit connection.

6. The circuit according to claim 2, In order to control the plurality of driving devices so that the pair of LED channels operate in the first state, the processing circuit device is configured as follows: Control the first LED channel of the pair of LED channels to turn on; and Control the second LED channel of the pair of LED channels to turn off. In order to control the plurality of driving devices so that the pair of LED channels operate in the second state, the processing circuit device is configured as follows: Control the first LED channel of the pair of LED channels to turn on; and Control the second LED channel of the pair of LED channels to turn on, and In order to determine whether the short-circuit connection exists based on the comparison between the difference and the threshold difference, the processing circuit device is configured to: When the difference is greater than the threshold difference, it is determined that the short-circuit connection does not exist; and When the difference is not greater than the threshold difference, it is determined that the short-circuit connection exists.

7. The circuit according to claim 2, wherein the processing circuit device comprises: A capacitor is configured to receive the first electrical signal from the second LED channel of the pair of LED channels; as well as The amplifier is configured as follows: Receive the second electrical signal from the output of the second LED channel of the pair of LED channels; Receive a third electrical signal, the third electrical signal representing the sum of the differences between the first electrical signal output from the capacitor and the threshold value; as well as An amplifier signal is generated based on the second electrical signal and the third electrical signal, and the amplifier signal indicates whether the short circuit connection exists between the pair of LED channels.

8. The circuit according to claim 2, wherein the processing circuit device comprises: The analog-to-digital converter (ADC) is configured as follows: Convert the first electrical signal into a first digital signal; and Convert the second electrical signal into a second digital signal; as well as The amplifier is configured as follows: Receive the second digital signal from the ADC; Receive a third digital signal, the third digital signal representing the sum of the threshold difference and the first digital signal output from the ADC; as well as An amplifier signal is generated based on the second digital signal and the third digital signal, the amplifier signal indicating whether the short circuit connection exists between the pair of LED channels.

9. The circuit of claim 1, wherein the plurality of LED channels are arranged in a sequence of LED channels, and wherein a pair of LED channels represents an adjacent pair of LED channels within the sequence of LED channels.

10. The circuit of claim 1, wherein the pair of LED channels is a first pair of LED channels, wherein the short-circuit connection is a first short-circuit connection, and wherein the processing circuit device is further configured to: The plurality of driving devices are controlled so that a second pair of LED channels among the plurality of LED channels operates in the first state during a third time period and in the second state during a fourth time period; Compare the third electrical signal with the fourth electrical signal, wherein the third electrical signal corresponds to the first state of the pair of LED channels, and the fourth electrical signal corresponds to the second state of the pair of LED channels; and The comparison between the third electrical signal and the fourth electrical signal determines whether a second short-circuit connection exists between the second pair of LED channels.

11. The circuit of claim 10, wherein the plurality of LED channels are arranged in a sequence of LED channels, wherein the first pair of LED channels represents a first pair of adjacent LED channels within the sequence of LED channels, wherein the second pair of LED channels represents a second pair of adjacent LED channels within the sequence of LED channels, wherein the first pair of adjacent LED channels includes a first LED channel and a second LED channel, and wherein the second pair of adjacent LED channels includes the second LED channel and a third LED channel.

12. The circuit according to claim 1, further comprising: The plurality of driving devices, wherein each of the plurality of driving devices controls whether a corresponding LED channel among the plurality of LED channels is turned on or off. When the processing circuit device controls one of the plurality of driving devices to turn on one of the plurality of LED channels, the amplitude of the current output from the LED channel is in the range of 2 mA to 1000 mA. When the processing circuit device controls one of the plurality of driving devices to turn off one of the plurality of LED channels, the amplitude of the current output from the LED channel is in the range of 2 microamps (μA) to 10 μA.

13. The circuit of claim 1, wherein each of the plurality of LED channels comprises one or more LEDs.

14. The circuit of claim 1, wherein each of the plurality of LED channels comprises one or more LEDs, and wherein the one or more of the plurality of LED channels comprises two or more LEDs.

15. A method for detecting one or more short-circuit connections in a plurality of light-emitting diode (LED) channels, wherein the method comprises: Multiple driving devices are controlled by a processing circuit device so that a pair of LED channels among the multiple LED channels operate in a first state during a first time period and in a second state during a second time period. The processing circuit device compares a first electrical signal with a second electrical signal, wherein the first electrical signal corresponds to the first state of the pair of LED channels and the second electrical signal corresponds to the second state of the pair of LED channels; as well as The processing circuit determines whether a short circuit exists between the pair of LED channels based on the comparison between the first electrical signal and the second electrical signal. The state of a pair of LED channels is determined by the on / off state of each LED channel in the corresponding LED channel.

16. The method of claim 15, wherein the pair of LED channels comprises a first LED channel and a second LED channel, and wherein the method further comprises: The first electrical signal is received when the pair of LED channels are operating in the first state; as well as The second electrical signal is received when the pair of LED channels are operating in the second state. The comparison of the first electrical signal and the second electrical signal includes determining the difference between the first electrical signal and the second electrical signal, and Determining whether the short-circuit connection exists includes: The difference between the first electrical signal and the second electrical signal is compared with a threshold difference. as well as The existence of the short-circuit connection is determined based on the comparison between the difference and the threshold difference.

17. The method according to claim 16, Controlling the plurality of driving devices to enable the pair of LED channels to operate in the first state includes: Control the first LED channel of the pair of LED channels to turn off; as well as Turn off the second LED channel in the pair of LED channels. Controlling the plurality of driving devices to enable the pair of LED channels to operate in the second state includes: Controlling the first LED channel of the pair of LED channels to turn on; and Control the second LED channel of the pair of LED channels to turn off, and Determining whether the short-circuit connection exists based on the comparison between the difference and the threshold includes: When the difference is greater than the threshold difference, it is determined that the short-circuit connection exists; and When the difference is not greater than the threshold difference, it is determined that the short-circuit connection does not exist.

18. The method according to claim 16, Controlling the plurality of driving devices to enable the pair of LED channels to operate in the first state includes: Control the first LED channel of the pair of LED channels to be turned on; as well as Control the second LED channel of the pair of LED channels to turn off. Controlling the plurality of driving devices to enable the pair of LED channels to operate in the second state includes: Controlling the first LED channel of the pair of LED channels to turn on; and Controlling the second LED channel of the pair of LED channels to turn on, and Determining whether the short-circuit connection exists based on the comparison between the difference and the threshold includes: When the difference is greater than the threshold difference, it is determined that the short-circuit connection does not exist; and The existence of the short-circuit connection is determined when the difference is not greater than the threshold difference.

19. The method of claim 16, further comprising: The capacitor receives the first electrical signal from the second LED channel of the pair of LED channels; as well as The amplifier receives the second electrical signal from the output of the second LED channel of the pair of LED channels; The amplifier receives a third electrical signal, which represents the sum of the threshold difference and the first electrical signal output from the capacitor; as well as The amplifier generates an amplifier signal based on the second electrical signal and the third electrical signal, the amplifier signal indicating whether the short circuit connection exists between the pair of LED channels.

20. The method of claim 16, further comprising: The first electrical signal is converted into a first digital signal by an analog-to-digital converter (ADC). The ADC converts the second electrical signal into a second digital signal; as well as The second digital signal is received from the ADC by the amplifier; The amplifier receives a third digital signal, which represents the sum of the threshold difference and the first digital signal output from the ADC; as well as The amplifier generates an amplifier signal based on the second digital signal and the third digital signal, the amplifier signal indicating whether the short circuit connection exists between the pair of LED channels.

21. The method of claim 15, wherein the pair of LED channels is a first pair of LED channels, wherein the short-circuit connection is a first short-circuit connection, and wherein the method further comprises: The processing circuit device controls the plurality of driving devices so that the second pair of LED channels in the plurality of LED channels operates in the first state during a third time period and in the second state during a fourth time period; The processing circuit device compares a third electrical signal with a fourth electrical signal, wherein the third electrical signal corresponds to the first state of the pair of LED channels and the fourth electrical signal corresponds to the second state of the pair of LED channels; as well as The processing circuit device determines whether a second short-circuit connection exists between the second pair of LED channels based on the comparison between the third electrical signal and the fourth electrical signal.

22. A system comprising: Multiple light-emitting diode (LED) channels; as well as A circuit for detecting one or more short-circuit connections in the plurality of LED channels, wherein the circuit includes a processing circuit device configured to: Multiple driving devices are controlled to cause a pair of LED channels among the multiple LED channels to operate in a first state during a first time period and in a second state during a second time period; Compare the first electrical signal with the second electrical signal, wherein the first electrical signal corresponds to the first state of the pair of LED channels, and the second electrical signal corresponds to the second state of the pair of LED channels; and Based on the comparison between the first electrical signal and the second electrical signal, it is determined whether there is a short circuit connection between the pair of LED channels. The state of a pair of LED channels is determined by the on / off state of each LED channel in the corresponding LED channel.

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