Load protection method and device applied to LED lamp beads

Abstract

The invention provides a load protection method and device applied to an LED lamp bead, and relates to the technical field of LEDs, and the method comprises the steps: obtaining a load current and a load voltage which are outputted to an LED lamp bead load by an LED driving power supply; amplifying and shunting the load current to obtain a first branch signal and a second branch signal; transmitting the first branch signal to a hardware current limiting unit for threshold comparison, and limiting the load current through the hardware current limiting unit when the current value corresponding to the first branch signal exceeds a preset safety current threshold; and the second branch signal and the load voltage are transmitted to the control unit for current, voltage and power abnormity analysis, and when any abnormity exists, the control unit controls to cut off a load loop, so that the LED lamp bead load stops working. Through a protection mechanism of mutual cooperation of hardware current limiting and turn-off of the control unit, the problem that the lamp bead is easy to be broken down and burnt down due to slow protection response speed when the current of the LED lamp bead load is suddenly changed instantly is solved.

Description

Technical Field

[0001] This application relates to the technical field of LEDs, and in particular to a load protection method and device for LED chips. Background Technology

[0002] During the testing and aging process of LED driver power supplies, real LED chips need to be used as loads for PWM dimming tests. This is because LED chip loads are purely hardware-based, have no delay, and can quickly respond to changes in voltage and current. In contrast, ordinary analog LED loads have response delays and cannot meet the requirements of PWM dimming tests.

[0003] In related technical means, a current detection unit and a voltage detection unit are used to monitor the load current and load voltage in real time. The detected signals are transmitted to the microcontroller for sampling and analysis. When the detected current or voltage exceeds the preset threshold, a protection command is issued to cut off the load circuit, thereby realizing overcurrent and overvoltage protection for LED beads.

[0004] Although LED protection can be achieved through monitoring and judgment by a microcontroller, there is a problem with slow protection response when the current changes instantaneously. This is because the microcontroller needs to go through steps such as signal filtering, analog-to-digital conversion, data calculation, and condition judgment, and the whole process requires a delay of tens of milliseconds. LED beads have weak resistance to current surges, and a voltage fluctuation of 1V can cause a current fluctuation of several hundred milliamps. Such instantaneous surges are enough to break down and burn out the LED beads before the protection can be activated. Summary of the Invention

[0005] To overcome the problem that slow protection response speed of LED lamp beads when the load changes instantaneously with a sudden change in current, which makes the lamp beads easy to break down and burn out, this application provides a load protection method and device for LED lamp beads.

[0006] On one hand, the present invention provides a load protection method for LED beads, comprising: acquiring the load current and load voltage output from the LED driver power supply to the LED bead load; amplifying and shunting the load current to obtain a first branch signal and a second branch signal; transmitting the first branch signal to a hardware current limiting unit for threshold comparison, wherein when the current value corresponding to the first branch signal exceeds a preset safe current threshold, the load current is limited by the hardware current limiting unit; transmitting the second branch signal and the load voltage to a control unit for current anomaly, voltage anomaly, and power anomaly analysis, wherein when any anomaly exists, the load circuit is cut off by the control unit to stop the LED bead load from working.

[0007] Optionally, the step of obtaining the load current and load voltage output from the LED driver power supply to the LED lamp bead load includes: connecting a sampling resistor in series in the main circuit between the LED driver power supply and the LED lamp bead load, obtaining the load current by detecting the voltage drop across the sampling resistor; and connecting a voltage divider circuit in parallel across the LED lamp bead load, obtaining the load voltage by dividing and sampling the voltage across the LED lamp bead load through the voltage divider circuit.

[0008] Optionally, the step of amplifying and splitting the load current to obtain a first branch signal and a second branch signal includes: amplifying the load current through a preset first operational amplifier to obtain an amplified load current signal; and using a signal splitting node connected to the first operational amplifier to divide the amplified load current signal into a first branch signal and a second branch signal.

[0009] Optionally, the step of transmitting the first branch signal to the hardware current limiting unit for threshold comparison, and limiting the load current through the hardware current limiting unit when the current value corresponding to the first branch signal exceeds a preset safe current threshold, includes: transmitting the first branch signal to the hardware current limiting unit; wherein the hardware current limiting unit includes a current comparator and a MOSFET driving circuit; using the current comparator to compare the current value corresponding to the first branch signal with the preset safe current threshold in real time; when the current value corresponding to the first branch signal does not exceed the safe current threshold, using the MOSFET driving circuit to control the power MOSFET connected in series in the main circuit to be in a fully conducting state; when the current value corresponding to the first branch signal exceeds the safe current threshold, using the MOSFET driving circuit to adjust the gate voltage of the power MOSFET to enter the linear operating region, and limiting the current flowing through the main circuit within the safe current threshold range by dynamically adjusting the on-resistance of the power MOSFET.

[0010] Optionally, the step of transmitting the second branch signal and the load voltage to the control unit for current, voltage, and power anomaly analysis, and controlling the control unit to disconnect the load circuit to stop the LED lamp bead load from working when any anomaly exists, includes: transmitting the second branch signal and the load voltage to the control unit to obtain digital load current and digital load voltage; comparing the digital load current with a preset maximum current threshold to obtain a current comparison result; comparing the digital load voltage with the product of a preset maximum voltage threshold for a single LED lamp bead and the current number of LED lamp beads connected in series to obtain a voltage comparison result; calculating the digital load power based on the digital load current and digital load voltage; comparing the digital load power with a preset maximum power threshold to obtain a power comparison result; and determining that an anomaly exists when any of the comparison results of the current comparison result, the voltage comparison result, or the power comparison result is satisfied, and controlling the control unit to disconnect the load circuit to stop the LED lamp bead load from working.

[0011] Optionally, the step of transmitting the second branch signal and the load voltage to the control unit to obtain the digital load current and the digital load voltage includes: amplifying the load voltage through a preset second operational amplifier to obtain an amplified load voltage signal; transmitting the second branch signal and the load voltage to the control unit, wherein the control unit performs analog-to-digital conversion on the second branch signal and the amplified load voltage signal through a preset analog-to-digital conversion interface to obtain the digital load current and the digital load voltage.

[0012] Optionally, the step of comparing the digital load voltage with the product of a preset maximum voltage threshold for a single LED and the current number of LEDs connected in series to obtain a voltage comparison result includes: reading the preset maximum voltage threshold for a single LED and the current number of LEDs connected in series parameters from the storage unit of the control unit; multiplying the maximum voltage threshold for a single LED by the current number of LEDs connected in series parameters to obtain a total voltage safety threshold; and comparing the digital load voltage with the total voltage safety threshold to obtain a voltage comparison result.

[0013] On the other hand, this application also provides a load protection device for LED beads, including: an acquisition module for acquiring the load current and load voltage output from the LED driver power supply to the LED bead load; a shunt module for amplifying and shunting the load current to obtain a first branch signal and a second branch signal; a comparison module for transmitting the first branch signal to a hardware current limiting unit for threshold comparison, wherein when the current value corresponding to the first branch signal exceeds a preset safe current threshold, the load current is limited by the hardware current limiting unit; and an analysis module for transmitting the second branch signal and the load voltage to a control unit for current, voltage, and power anomaly analysis, wherein when any anomaly exists, the load circuit is cut off by the control unit to stop the LED bead load from working.

[0014] On the other hand, this application also provides an electronic device, the device including a processor and a memory, the memory storing at least one instruction or at least one program, the at least one instruction or the at least one program being loaded and executed by the processor to implement the load protection method for LED beads as described above.

[0015] On the other hand, this application also provides a computer-readable storage medium storing at least one instruction or at least one program, which is loaded and executed by a processor to implement the load protection method for LED beads as described in any of the above.

[0016] The load protection method and device for LED chips provided in this application have the following technical effects: Through the protection mechanism of hardware current limiting and control unit shutdown working together, when there is an error in the configuration of drive parameters, abnormal power output or abnormal load state during the testing or aging process of LED driver power supply, the load current can be limited in the early stage of the abnormality, and the load circuit can be cut off in time when the abnormality persists, thereby preventing the LED chips from breaking down or burning out due to overcurrent, overvoltage or overpower operation, and improving the safety and reliability of LED chips as real loads in testing and aging applications. Attached Figure Description

[0017] To more clearly illustrate the technical solutions and advantages in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1This is a schematic flowchart of a load protection method for LED beads provided in an embodiment of the present invention; Figure 2 This is a schematic block diagram of a load protection method for LED beads provided in an embodiment of the present invention; Figure 3 This is a schematic block diagram of the structure of a load protection device for LED beads provided in an embodiment of the present invention; Figure 4 This is a schematic block diagram of the structure of the electronic device provided in the embodiment of the present invention.

[0019] Explanation of reference numerals in the attached figures: 10. Load protection device for LED beads; 11. Acquisition module; 12. Current shunting module; 13. Comparison module; 14. Analysis module; 20. Electronic equipment; 21. Bus; 22. Processor; 23. Transceiver; 24. Memory. Detailed Implementation

[0020] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0021] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or server that comprises a series of steps or sub-modules is not necessarily limited to those steps or sub-modules explicitly listed, but may include other steps or sub-modules not explicitly listed or inherent to such processes, methods, products, or devices.

[0022] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0023] Example 1: like Figure 1 and Figure 2As shown, this application provides a load protection method for LED chips, which can be used to provide real-time protection control for LED chips, which serve as the actual load, during PWM dimming and aging tests of LED driver power supplies. This load protection method achieves rapid protection of LED chips under abnormal operating conditions by synchronously acquiring load current and load voltage, and combining this with hardware current limiting and control unit analysis and processing. Specifically, this load protection method includes: Step S10: Obtain the load current and load voltage of the LED driver power supply output to the LED lamp bead load.

[0024] By establishing an electrical parameter sampling path between the LED driver power supply and the LED chip load, the actual operating current flowing through the LED chip load and the actual operating voltage across the LED chip load are synchronously collected. The collected load current and load voltage are used to characterize the current operating state of the LED chip load and serve as the basis for subsequent protection judgments. The load current reflects the current withstand capability of the LED chip load under the current driving conditions, and the load voltage reflects the voltage withstand capability of the LED chip load under the current connection state and driving parameters. Both are real-time electrical signals directly derived from the main circuit and the load end.

[0025] During the process of supplying power from the LED driver power supply output to the LED lamp bead load, by setting an electrical parameter sampling structure in the power supply circuit, the current and voltage values ​​of the LED lamp bead load can be acquired in real time without changing the original power supply path topology, so that the subsequent protection logic can make judgments based on the actual load state.

[0026] In another preferred example, step S10 can preferably be implemented as follows: A sampling resistor is connected in series in the main circuit between the LED driver power supply and the LED chip load. The load current is obtained by detecting the voltage drop across the sampling resistor.

[0027] A sampling resistor is connected in series in the main circuit between the output of the LED driver power supply and the input of the LED chip load. This sampling resistor has a preset small resistance value, used to convert the load current in the main circuit into a proportional voltage signal without significantly affecting the main circuit's operation. By detecting the voltage drop across the sampling resistor, the voltage signal is converted into the corresponding load current value according to Ohm's law, thus achieving real-time acquisition of the load current. The resistance value of the sampling resistor is selected based on the rated operating current range of the LED chip load, ensuring that the voltage drop across it is within the effective detection range of the subsequent signal processing circuit under maximum safe current conditions.

[0028] When the maximum safe operating current of the LED bead load is 1A, a sampling resistor with a resistance of 0.1Ω can be selected. When the load current is 1A, a voltage drop of about 0.1V is generated across the sampling resistor. This voltage drop can be stably acquired and processed by the subsequent operational amplifier to obtain the corresponding load current signal.

[0029] A voltage divider circuit is connected in parallel across the LED lamp bead load. The voltage across the LED lamp bead load is sampled by the voltage divider circuit to obtain the load voltage.

[0030] A voltage divider circuit is connected in parallel between the positive and negative terminals of the LED bead load. This circuit, consisting of at least two resistors connected in series, proportionally reduces the actual operating voltage across the LED bead load to a range acceptable to the control unit and subsequent signal processing circuits. The actual load voltage across the LED bead load is calculated by detecting the voltage value at a preset node in the voltage divider circuit and considering the voltage division ratio. The voltage division ratio is set based on the maximum operating voltage of the LED bead load, ensuring that the divided voltage does not exceed the input upper limit of the subsequent circuitry under the maximum permissible load voltage condition.

[0031] When the total voltage of the LED lamp bead load is 48V under the maximum number of lamp beads, a voltage division ratio of 1:10 can be used to make the voltage after voltage division 4.8V, so that it can be stably acquired by the subsequent operational amplifier or analog-to-digital converter interface to obtain the corresponding load voltage signal.

[0032] Step S20: Amplify and shunt the load current to obtain the first branch signal and the second branch signal.

[0033] The voltage signal corresponding to the load current undergoes signal conditioning, amplification to improve signal amplitude and anti-interference capability, and then splits into two independent signal channels at the amplified signal node. These channels are used for subsequent hardware current limiting and control unit analysis, respectively, enabling parallel use of the load current signal at different protection levels. The first branch signal directly participates in the current threshold comparison of the hardware current limiting unit, while the second branch signal is transmitted to the control unit for digital processing and anomaly analysis. The two branches maintain a consistent signal source but are functionally independent.

[0034] After the voltage signal obtained from both ends of the sampling resistor is input to the amplifier circuit, a shunt node is set at the output of the amplifier circuit so that the same load current signal can be used by the hardware current limiting unit and the control unit at the same time, avoiding signal deviation caused by repeated sampling.

[0035] In another preferred example, step S20 can preferably be implemented as follows: The load current is amplified by a preset first operational amplifier to obtain the amplified load current signal.

[0036] The voltage signal generated by the sampling resistor is input to the first operational amplifier. The first operational amplifier adopts a proportional amplifier circuit structure. By setting the ratio of the feedback resistor to the input resistor, it linearly amplifies the voltage signal corresponding to the load current, ensuring that its amplitude meets the accuracy requirements of subsequent comparison and sampling. The amplification factor of the first operational amplifier is set according to the resistance value of the sampling resistor and the maximum value of the load current, so that under the condition of maximum safe current, its output signal amplitude is within a preset effective operating range.

[0037] When the voltage signal output by the sampling resistor is in the range of 0 to 0.1V, the amplification factor of the first operational amplifier can be set to 20, so that the amplified load current signal ranges from 0 to 2V, thereby meeting the input requirements of the hardware comparator and analog-to-digital converter interface.

[0038] The amplified load current signal is divided into a first branch signal and a second branch signal using a signal splitting node connected to the first operational amplifier.

[0039] A signal splitter node is set at the output of the first operational amplifier. Through wire connection or impedance matching, the amplified load current signal is simultaneously output to the first branch signal channel and the second branch signal channel, ensuring that the two signals maintain consistency in amplitude, phase, and time characteristics. The first branch signal is directly transmitted to the hardware current limiting unit via an analog signal path, while the second branch signal is transmitted to the input port of the control unit via an analog signal path for subsequent analog-to-digital conversion and anomaly analysis.

[0040] For example, two parallel output nodes are set at the output of the first operational amplifier. One node is directly connected to the current comparison input of the hardware current limiting unit, and the other node is connected to the analog-to-digital conversion interface input of the control unit, thereby realizing the dual-channel parallel transmission of the same load current signal.

[0041] Step S30: The first branch signal is transmitted to the hardware current limiting unit for threshold comparison. When the current value corresponding to the first branch signal exceeds the preset safe current threshold, the load current is limited by the hardware current limiting unit.

[0042] The first branch signal is input as an analog current detection signal to the hardware current limiting unit. The hardware circuit performs real-time threshold judgment on the current value corresponding to the first branch signal. When the detected current value exceeds the preset safe current threshold, the hardware current limiting unit directly limits the load current in the main circuit without relying on the control unit, thus suppressing further increases in the load current. The hardware current limiting unit is implemented based on analog circuitry; its operation does not involve sampling, filtering, calculation, or program judgment. It can responsively adjust the main circuit current at the instant of a sudden change in load current, thereby avoiding overcurrent damage to the LED beads due to processing delays in the control unit.

[0043] For example, when the output parameters of the LED driver power supply are abnormal and the output voltage suddenly increases, the load current rises rapidly, and the amplitude of the first branch signal increases synchronously. After the hardware current limiting unit detects that the signal exceeds the safe current threshold, it immediately limits the main circuit current, so that the current flowing through the LED lamp bead load is limited to a safe range.

[0044] In another preferred example, step S30 can preferably be implemented as follows: The first branch signal is transmitted to the hardware current limiting unit; the hardware current limiting unit includes a current comparator and a MOSFET driver circuit.

[0045] The first branch signal is directly input to the current comparator input terminal in the hardware current limiting unit via an analog signal channel. The hardware current limiting unit consists of a current comparator and a MOSFET driver circuit connected to its output terminal. It is used to drive and control the power MOSFET connected in series in the main circuit based on the comparison result between the first branch signal and the safe current threshold. Specifically, the current comparator performs real-time comparison between the first branch signal and the safe current threshold, and the MOSFET driver circuit adjusts the gate drive voltage of the power MOSFET according to the output state of the current comparator, thereby changing the conduction state of the power MOSFET in the main circuit.

[0046] By inputting the first branch signal to the non-inverting input of the current comparator, inputting the reference voltage representing the safe current threshold to the inverting input of the current comparator, and connecting the output of the current comparator to the control input of the MOSFET drive circuit, a closed-loop current limiting control structure based on the current magnitude is formed.

[0047] A current comparator is used to compare the current value corresponding to the first branch signal with a preset safe current threshold in real time.

[0048] The current comparator continuously compares the instantaneous voltage value of the first branch signal with a reference voltage representing the safe current threshold. Changes in the comparator's output level reflect whether the current value corresponding to the first branch signal exceeds the safe current threshold. This comparison process is implemented using analog circuitry and does not rely on the control unit, thus ensuring real-time performance. The safe current threshold is generated by a reference voltage source connected to the current comparator. This reference voltage source is set according to the maximum allowable operating current of the LED chip load, causing the current comparator to flip its state when the first branch signal reaches the corresponding current value.

[0049] When the maximum safe current of the LED lamp bead load is 1A, and the voltage of the first branch signal is linearly proportional to the load current, the current comparator can be set to change its output state when the first branch signal corresponds to a current of 1A by setting a reference voltage, thereby triggering the subsequent MOSFET drive circuit to enter the current limiting control state.

[0050] When the current value corresponding to the first branch signal does not exceed the safe current threshold, the power MOSFET connected in series in the main circuit is controlled to be in a fully conducting state by the MOSFET drive circuit.

[0051] When the comparison result of the current comparator shows that the current value corresponding to the first branch signal does not exceed the safe current threshold, the output of the current comparator remains at a level indicating normal operation. The MOSFET driver circuit provides sufficient drive voltage to the gate of the power MOSFET based on this output level, so that the power MOSFET is in a fully conducting state. In the fully conducting state of the power MOSFET, its drain-source on-resistance is at its minimum value, the load current in the main circuit is not subject to additional restrictions, and the current output by the LED driver power supply can flow normally through the LED chip load, ensuring that the LED chip works stably under normal testing or aging conditions.

[0052] For example, when the load current corresponding to the first branch signal is 0.6A, which is lower than the preset 1A safe current threshold, the MOSFET drive circuit outputs the rated drive voltage to the gate of the power MOSFET, so that the power MOSFET remains fully turned on and the main circuit current is not limited.

[0053] When the current value corresponding to the first branch signal exceeds the safe current threshold, the gate voltage of the power MOSFET is adjusted by the MOSFET drive circuit to enter the linear operating region. The current flowing through the main circuit is limited to the safe current threshold range by the on-resistance of the dynamically adjusted power MOSFET.

[0054] When the current comparator detects that the current value corresponding to the first branch signal exceeds the safe current threshold, the output state of the current comparator changes. Based on this change, the MOSFET driver circuit dynamically reduces the driving voltage applied to the gate of the power MOSFET, causing the power MOSFET to transition from a fully on state to the linear operating region. When the power MOSFET is in the linear operating region, its drain-source on-resistance adjusts with the gate voltage. The MOSFET bears part of the voltage drop in the main circuit, thereby limiting the current amplitude flowing through the main circuit and clamping the load current within the range corresponding to the safe current threshold. This current limiting process is completed in real-time by the hardware circuitry, providing rapid protection for the LED chip load under abnormal current conditions.

[0055] For example, when the load current corresponding to the first branch signal rises to 1.3A and exceeds the safe current threshold of 1A, the MOSFET driver circuit reduces the gate voltage of the power MOSFET, causing the power MOSFET to enter the linear operating region. By increasing its on-resistance, the main circuit current is limited to around 1A, thereby preventing the LED beads from being damaged due to instantaneous overcurrent.

[0056] Step S40: Transmit the second branch signal and load voltage to the control unit for current abnormality, voltage abnormality and power abnormality analysis. When any abnormality exists, the control unit controls the disconnection of the load circuit so that the LED lamp bead load stops working.

[0057] The second branch signal and the load voltage signal are simultaneously transmitted to the control unit. The control unit samples, digitizes, and performs threshold comparison analysis on these signals to determine if there are any abnormalities in the current, voltage, or power of the LED lamp bead load. When any abnormal condition is detected, the control unit outputs a control signal to disconnect the load circuit, causing the LED lamp bead load to stop working and thus preventing damage to the LED lamp beads due to continuous electrical stress under abnormal operating conditions. The abnormal analysis process involving the control unit is implemented based on software logic. It is used to further determine the abnormal states already limited by the hardware current limiting unit and to execute a shutdown action if the abnormality persists, completely disconnecting the load circuit from the power supply path.

[0058] Even though the hardware current limiting unit has already limited the load current, the LED driver power supply output parameters are still in an abnormal state. The control unit analyzes the second branch signal and load voltage, and after confirming that the abnormal conditions are met, it controls the disconnection of the load circuit, thereby avoiding the risk of overheating caused by the power MOSFET operating in the linear region for a long time.

[0059] In another preferred example, step S40 can preferably be implemented as follows: The second branch signal and load voltage are transmitted to the control unit to obtain the digital load current and digital load voltage.

[0060] The analog load current signal corresponding to the second branch signal and the analog voltage signal corresponding to the load voltage are input to the control unit. The control unit's internal signal sampling and processing circuit digitizes these analog signals to obtain digital load current and digital load voltage values ​​for subsequent analysis. These digital load current and digital load voltage values ​​serve as digital parameters reflecting the actual operating state of the current LED bead load and are used within the control unit to execute logic for determining current anomalies, voltage anomalies, and power anomalies.

[0061] By inputting the analog voltage corresponding to the second branch signal to the sampling interface of the control unit, and simultaneously inputting the analog voltage corresponding to the load voltage to another sampling interface, the corresponding digital load current and digital load voltage are obtained after sampling.

[0062] Furthermore, the step of transmitting the second branch signal and load voltage to the control unit to obtain the digital load current and digital load voltage can also be preferably implemented as follows: The load voltage is amplified by a preset second operational amplifier to obtain the amplified load voltage signal.

[0063] The load voltage signal output from the voltage divider circuit is input to the second operational amplifier. The second operational amplifier amplifies the load voltage signal proportionally to match its amplitude to the input range of the analog-to-digital converter interface of the control unit, thereby improving the sampling accuracy of the load voltage. The amplification factor of the second operational amplifier is set according to the maximum possible value of the load voltage and the range of the analog-to-digital converter interface to ensure that the amplified load voltage signal does not saturate under the maximum load voltage condition.

[0064] For example, when the range of the load voltage signal after voltage division is 0 to 1V and the input range of the analog-to-digital converter interface is 0 to 3.3V, the amplification factor of the second operational amplifier can be set to 3 so that the amplified load voltage signal covers the range of 0 to 3V.

[0065] The second branch signal and the load voltage are transmitted to the control unit. In the control unit, the second branch signal and the amplified load voltage signal are converted from analog to digital through a preset analog-to-digital conversion interface to obtain the digital load current and the digital load voltage.

[0066] The second branch signal and the load voltage signal processed by the second operational amplifier are input to the analog-to-digital converter (ADC) interface within the control unit. The ADC interface samples and quantizes the analog signals to generate corresponding digital signals. Specifically, the ADC interface converts the input signals according to a preset sampling resolution and sampling period, ensuring that the obtained digital load current and digital load voltage accurately reflect the electrical parameter state of the load at the current moment.

[0067] The control unit uses a 12-bit analog-to-digital converter interface to sample input signals in the range of 0 to 3.3V, thereby converting the second branch signal and the amplified load voltage signal into corresponding digital quantities for subsequent comparison and analysis.

[0068] The digital load current is compared with the preset maximum current threshold to obtain the current comparison result. The digital load voltage is compared with the product of the preset maximum voltage threshold for a single LED and the current number of LEDs connected in series to obtain the voltage comparison result.

[0069] The control unit compares the acquired digital load current with a preset, stored maximum current threshold to determine if the current load current exceeds the maximum allowable operating current range of the LED chips. Simultaneously, it compares the digital load voltage with a total safe voltage threshold calculated from the maximum voltage threshold of a single LED chip and the current number of LED chips connected in series to determine if the current load voltage is within a safe range. This comparison process is implemented internally within the control unit using numerical comparisons, and the comparison results are used to indicate abnormal current and abnormal voltage conditions, respectively.

[0070] For example, when the actual current corresponding to the digital load current is 1.2A, and the preset maximum current threshold is 1A, the current comparison result is judged as abnormal; when the actual voltage corresponding to the digital load voltage exceeds the calculated total voltage safety threshold, the voltage comparison result is judged as abnormal.

[0071] Furthermore, the step of comparing the digital load voltage with the product of a preset maximum voltage threshold for a single LED and the current number of LEDs connected in series to obtain the voltage comparison result can also be preferably implemented as follows: Read the preset maximum voltage threshold for a single LED and the current number of LEDs connected in series from the storage unit of the control unit.

[0072] The control unit reads pre-stored parameters from its internal storage unit, including the maximum voltage threshold of a single LED and the actual number of LEDs connected in series in the current LED load. These parameters are used to determine the total safe voltage range of the LED load under the current configuration. The maximum voltage threshold of a single LED is determined by the LED specification parameters, and the current number of LEDs connected in series is configured by the user or written to the storage unit during the load initialization phase.

[0073] For example, in a load consisting of 16 LED beads connected in series, if the maximum voltage threshold of a single LED bead is 3V, the control unit will read the corresponding parameters from the storage unit for subsequent calculations.

[0074] The total voltage safety threshold is obtained by multiplying the maximum voltage threshold of a single LED bead with the number of LED beads connected in series.

[0075] The control unit performs a multiplication operation on the maximum voltage threshold of a single LED and the current number of LEDs connected in series to calculate the total voltage safety threshold corresponding to the current load configuration, which is used to limit the maximum operating voltage that the LED load can withstand.

[0076] For example, when the maximum voltage threshold of a single LED bead is 3V, and the current number of LED beads connected in series is 16, the total safe voltage threshold is 48V obtained through multiplication.

[0077] The digital load voltage is compared with the total voltage safety threshold to obtain the voltage comparison result.

[0078] The control unit compares the actual load voltage corresponding to the digital load voltage with the calculated total voltage safety threshold. When the load voltage exceeds the total voltage safety threshold, the voltage comparison result is determined to be an abnormal state.

[0079] For example, when the actual load voltage corresponding to the digital load voltage is 50V, which is higher than the total voltage safety threshold of 48V, the control unit determines that there is a voltage abnormality.

[0080] The load power digital quantity is calculated based on the load current digital quantity and the load voltage digital quantity. The load power digital quantity is then compared with the preset maximum power threshold to obtain the power comparison result.

[0081] The control unit calculates the corresponding digital load power based on the digital load current and digital load voltage. This calculation uses the power calculation formula P = U × I, which is an existing method in the electrical engineering field for calculating DC load power. Subsequently, the calculated digital load power is compared with a preset maximum power threshold to determine whether the current load power exceeds the upper limit that the LED lamp bead load can withstand.

[0082] For example, when the actual current corresponding to the digital load current is 1A and the actual voltage corresponding to the digital load voltage is 48V, the calculated load power is 48W. When the preset maximum power threshold is 40W, the power comparison result is judged as abnormal.

[0083] If any of the comparison results—current comparison, voltage comparison, or power comparison—is satisfied, an abnormality is determined, and the load circuit is cut off by the control unit to stop the LED bead load from working.

[0084] The control unit comprehensively judges the current comparison results, voltage comparison results, and power comparison results. When any comparison result shows that the corresponding parameter exceeds a preset safety threshold, the current LED lamp bead load is determined to be in an abnormal state. After determining the abnormality, the control unit outputs a shutdown control signal to control the switching devices or relays in the load circuit to disconnect, thereby cutting off the electrical connection between the LED driver power supply and the LED lamp bead load. The shutdown control state remains effective until the abnormality is eliminated to prevent the LED lamp bead load from being repeatedly powered on under abnormal conditions.

[0085] For example, when the load current is limited to a safe range by the hardware current limiting unit, but the power comparison result is consistently determined to be abnormal, the control unit outputs a shutdown control signal to cut off the load circuit and stop the LED lamp bead load from working.

[0086] In this embodiment, the load current and load voltage output from the LED driver power supply to the LED lamp bead load are acquired in real time, and the load current is amplified and shunted so that the same load current signal is used for hardware current limiting and control unit anomaly analysis. Specifically, the hardware current limiting unit based on the first branch signal limits the main circuit current in real time when the load current exceeds the safe current threshold to suppress the instantaneous impact of current surges on the LED lamp beads. At the same time, the control unit based on the second branch signal and the load voltage signal performs digital analysis of the load current, voltage and power, and controls the disconnection of the load circuit when an abnormal current, voltage or power is detected, so that the LED lamp bead load stops working. Through the aforementioned protection mechanism that combines hardware current limiting and control unit shutdown, when errors occur in drive parameter configuration, abnormal power output, or abnormal load conditions during LED driver power supply testing or aging, the load current can be limited in the early stages of the abnormality, and the load circuit can be cut off in time when the abnormality persists. This prevents LED beads from breaking down or burning out due to overcurrent, overvoltage, or overpower operation, thereby improving the safety and reliability of LED beads as real loads in testing and aging applications.

[0087] Example 2: like Figure 3 As shown, this application also provides a load protection device for LED chips, which specifically includes: The acquisition module is used to acquire the load current and load voltage output from the LED driver power supply to the LED lamp bead load.

[0088] The shunt module is used to amplify and shunt the load current to obtain the first branch signal and the second branch signal.

[0089] The comparison module is used to transmit the first branch signal to the hardware current limiting unit for threshold comparison. When the current value corresponding to the first branch signal exceeds the preset safe current threshold, the load current is limited by the hardware current limiting unit.

[0090] The analysis module is used to transmit the second branch signal and load voltage to the control unit for current, voltage and power anomaly analysis. When any anomaly is found, the control unit controls the disconnection of the load circuit to stop the LED lamp bead load from working.

[0091] In this embodiment, by setting up an acquisition module for obtaining load current and load voltage, a current shunting module for amplifying and shunting the load current, a comparison module for implementing hardware current limiting based on the first branch signal, and an analysis module for anomaly analysis based on the second branch signal and load voltage, the load protection device can simultaneously possess the ability to instantly limit current and shut down in abnormal states when the LED driver power supply output is abnormal. Through the functional collaboration of the comparison module and the analysis module, when the load current shows a sudden increase, the hardware current limiting unit can first limit the load current. When an abnormal current, voltage, or power anomaly is detected and persists, the control unit then controls the disconnection of the load circuit. Thus, multi-level protection of the LED lamp bead load is achieved without relying on complex software control, improving the reliability and safety of the load protection device in testing and aging application scenarios.

[0092] Example 3: This application also provides an electronic device, which includes a processor and a memory, wherein the memory stores at least one instruction or at least one program, and the processor loads and executes the at least one instruction or at least one program to implement the load protection method for LED beads as described in Example 1.

[0093] In this embodiment, by setting up a processor and a memory in the electronic device, and storing instructions or programs in the memory for implementing a load protection method for LED beads, the processor, when executing the instructions or programs, can complete the acquisition of load current and load voltage, load current shunting processing, hardware current limiting trigger condition judgment, and load abnormal state analysis and loop disconnection control. By deploying the load protection method described in Embodiment 1 in the form of program instructions in the electronic device, the electronic device, when used as part of an LED driver power supply testing or aging system, can perform real-time monitoring and protection control of the LED bead load operating status, thereby avoiding damage to the LED beads due to abnormal driving parameters or abnormal load status, and improving the overall stability of the system operation.

[0094] In one alternative embodiment, an electronic device is provided, such as Figure 4 As shown, Figure 4 The illustrated electronic device includes a processor and a memory. The processor and memory are connected, for example, via a bus. Optionally, the electronic device may also include a transceiver, which can be used for data interaction between the electronic device and other electronic devices, such as sending and / or receiving data. It should be noted that in practical applications, the transceiver is not limited to one unit, and the structure of this electronic device does not constitute a limitation on the embodiments of this application.

[0095] Example 4: This application also provides a computer-readable storage medium storing at least one instruction or at least one program, which is loaded and executed by a processor to implement the load protection method for LED beads as described in Embodiment 1.

[0096] In this embodiment, by storing instructions or programs for implementing a load protection method for LED beads in a computer-readable storage medium, the instructions or programs, when loaded and executed by a processor, can perform tasks such as acquiring and processing load current and load voltage, shunting and limiting load current, and analyzing and disconnecting abnormal load conditions. This method allows the load protection method to be stored and distributed as a software program, facilitating deployment and reuse in different electronic devices or testing systems. Thus, it achieves safe protection of the LED bead load without changing the hardware structure, enhancing the versatility and implementation flexibility of the solution.

[0097] It should be noted that the order of the embodiments described above is merely for descriptive purposes and does not represent the superiority or inferiority of the embodiments. Furthermore, the above description focuses on specific embodiments of this application. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps described in the claims can be performed in a different order than that shown in the embodiments and still achieve the desired results. Additionally, the processes depicted in the drawings do not necessarily require a specific or sequential order to achieve the desired results. In some implementations, multitasking and parallel processing are also possible or may be advantageous.

[0098] The various embodiments in this application are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, the device, equipment, and storage medium embodiments are basically similar to the method embodiments, so the descriptions are relatively simple; relevant parts can be referred to the descriptions of the method embodiments.

[0099] Those skilled in the art will understand that all or part of the steps of the above embodiments can be implemented by hardware, or by a program instructing the relevant hardware to implement them. The program can be stored in a computer-readable storage medium, such as a read-only memory, a disk, or an optical disk.

[0100] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A load protection method for LED lamp beads, characterized in that, include: Obtain the load current and load voltage output from the LED driver power supply to the LED lamp bead load; The load current is amplified and splittered to obtain the first branch signal and the second branch signal; The first branch signal is transmitted to the hardware current limiting unit for threshold comparison. When the current value corresponding to the first branch signal exceeds the preset safe current threshold, the load current is limited by the hardware current limiting unit. The second branch signal and the load voltage are transmitted to the control unit for analysis of current anomalies, voltage anomalies, and power anomalies. When any anomaly is present, the control unit controls the disconnection of the load circuit to stop the LED lamp bead load from working.

2. The load protection method for LED chips according to claim 1, characterized in that, The step of obtaining the load current and load voltage output from the LED driver power supply to the LED lamp bead load includes: A sampling resistor is connected in series in the main circuit between the LED driver power supply and the LED lamp bead load. The load current is obtained by detecting the voltage drop across the sampling resistor. A voltage divider circuit is connected in parallel across the LED lamp bead load. The voltage across the LED lamp bead load is sampled by the voltage divider circuit to obtain the load voltage.

3. The load protection method for LED chips according to claim 1, characterized in that, The step of amplifying and shunting the load current to obtain the first branch signal and the second branch signal includes: The load current is amplified by a preset first operational amplifier to obtain an amplified load current signal; The amplified load current signal is divided into a first branch signal and a second branch signal using a signal splitting node connected to the first operational amplifier.

4. The load protection method for LED chips according to claim 2, characterized in that, The step of transmitting the first branch signal to the hardware current limiting unit for threshold comparison, and limiting the load current through the hardware current limiting unit when the current value corresponding to the first branch signal exceeds a preset safe current threshold, includes: The first branch signal is transmitted to the hardware current limiting unit; wherein, the hardware current limiting unit includes a current comparator and a MOSFET driving circuit; The current comparator is used to compare the current value corresponding to the first branch signal with a preset safe current threshold in real time. When the current value corresponding to the first branch signal does not exceed the safe current threshold, the power MOSFET connected in series in the main circuit is controlled to be in a fully conducting state by the MOSFET driving circuit. When the current value corresponding to the first branch signal exceeds the safe current threshold, the gate voltage of the power MOSFET is adjusted to enter the linear operating region by the MOSFET driving circuit, and the current flowing through the main circuit is limited to the safe current threshold range by the dynamically adjusted on-resistance of the power MOSFET.

5. The load protection method for LED chips according to claim 1, characterized in that, The step of transmitting the second branch signal and the load voltage to the control unit for current, voltage, and power anomaly analysis, and controlling the control unit to disconnect the load circuit to stop the LED lamp bead load from working when any anomaly is found, includes: The second branch signal and the load voltage are transmitted to the control unit to obtain the digital load current and digital load voltage. The load current digital value is compared with the preset maximum current threshold to obtain the current comparison result. The load voltage digital value is compared with the product of the preset maximum voltage threshold of a single LED and the current number of LEDs connected in series to obtain the voltage comparison result. The load power digital quantity is calculated based on the load current digital quantity and the load voltage digital quantity, and the load power digital quantity is compared with a preset maximum power threshold to obtain a power comparison result; If any of the comparison results of the current comparison, the voltage comparison, or the power comparison is satisfied, an abnormality is determined, and the load circuit is cut off by the control unit to stop the LED lamp bead load from working.

6. The load protection method for LED chips according to claim 5, characterized in that, The step of transmitting the second branch signal and the load voltage to the control unit to obtain the digital values ​​of the load current and load voltage includes: The load voltage is amplified by a preset second operational amplifier to obtain an amplified load voltage signal; The second branch signal and the load voltage are transmitted to the control unit. In the control unit, the second branch signal and the amplified load voltage signal are converted from analog to digital through a preset analog-to-digital conversion interface to obtain the digital load current and the digital load voltage.

7. The load protection method for LED chips according to claim 5, characterized in that, The step of comparing the digital load voltage with the product of a preset maximum voltage threshold for a single LED and the current number of LEDs connected in series to obtain a voltage comparison result includes: Read the preset maximum voltage threshold for a single LED bead and the current number of LED beads connected in series from the storage unit of the control unit; The maximum voltage threshold of a single LED bead is multiplied by the number of LED beads connected in series to obtain the total voltage safety threshold. The digital load voltage is compared with the total voltage safety threshold to obtain the voltage comparison result.

8. A load protection device for LED lamp beads, characterized in that, include: The acquisition module is used to acquire the load current and load voltage output from the LED driver power supply to the LED lamp bead load; The current shunt module is used to amplify and shunt the load current to obtain the first branch signal and the second branch signal; The comparison module is used to transmit the first branch signal to the hardware current limiting unit for threshold comparison. When the current value corresponding to the first branch signal exceeds the preset safe current threshold, the load current is limited by the hardware current limiting unit. The analysis module is used to transmit the second branch signal and the load voltage to the control unit for current, voltage and power anomaly analysis. When any anomaly is found, the control unit controls the load circuit to be cut off so that the LED lamp bead load stops working.

9. An electronic device, characterized in that, The device includes a processor and a memory, the memory storing at least one instruction or at least one program, the at least one instruction or the at least one program being loaded and executed by the processor to implement claim 1. The load protection method for LED chips as described in any one of the 8.

10. A computer-readable storage medium, characterized in that, The storage medium stores at least one instruction or at least one program segment, which is loaded and executed by a processor to implement claim 1. The load protection method for LED chips as described in any one of the 8.

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