A light emitting diode protection regulation circuit and system

Abstract

The present application relates to the technical field of light emitting diode circuit, and particularly relates to a light emitting diode protection adjusting circuit and system. The light emitting diode protection adjusting circuit comprises an adjustable power supply, a master control chip, a first signal acquisition module, a second signal acquisition module, a constant current chip, a power supply adjusting feedback module and a light emitting channel. The light emitting channel comprises a switching element, a sampling resistor and a light emitting diode. An input end of the first signal acquisition module is connected in series between the switching element and the sampling resistor, and an output end of the first signal acquisition module is connected with the master control chip. One input end of the second signal acquisition module is connected in series between the sampling resistor and the light emitting diode, and the other input end of the second signal acquisition module is connected in series between the light emitting diode and the constant current chip. The master control chip is connected with the adjustable power supply through the power supply adjusting feedback module. The present application can realize independent fault detection, fault hardware isolation and power supply energy self-adaptive adjustment of multiple light emitting channels without changing the constant current chip.

Description

Technical Field

[0001] This invention relates to the field of light-emitting diode (LED) circuit technology, and in particular to an LED protection and regulation circuit and system. Background Technology

[0002] Light-emitting diode (LED) displays are widely used in outdoor advertising, stage performances, and information dissemination due to their advantages such as high brightness, high contrast, and long lifespan. Currently, LED displays are typically driven by constant current driver chips for scanning. Each output corresponds to one LED or LED string, and the constant current chip provides a stable operating current to each channel of LEDs to ensure consistent display brightness.

[0003] However, existing constant current drive solutions have significant shortcomings in single-channel fault protection. Conventional constant current drive chips do not have real-time detection and hardware isolation functions for single-channel open circuits and short circuits. When a short circuit fault occurs in a channel of LEDs, the impedance at the short circuit point drops sharply, generating a large current instantaneously. This causes the power supply voltage of the entire column to drop, resulting in display abnormalities such as dark lines and screen distortion. In severe cases, it can even burn out the driver chip, power module, and PCB board. When an open circuit fault occurs in a channel, it only manifests as a local dark spot. The system cannot identify the faulty channel or locate the fault, making maintenance and troubleshooting extremely difficult.

[0004] In summary, the industry currently lacks a technical solution for single-channel fault self-diagnosis and hardware isolation that can be achieved independently through peripheral circuits without modifying the constant current driver chip. Summary of the Invention

[0005] To solve the above-mentioned technical problems, or at least partially solve them, the present invention provides a light-emitting diode protection and adjustment circuit and system that does not require modification of the constant current driver chip and can realize independent fault detection, fault hardware isolation, and adaptive adjustment of power supply for multiple LED paths.

[0006] In a first aspect, the present invention provides a light-emitting diode protection and adjustment circuit, comprising: The system includes an adjustable power supply, a main control chip, multiple first signal acquisition modules, multiple second signal acquisition modules, a constant current chip, a power regulation feedback module, and multiple light-emitting channels; the first signal acquisition modules, the second signal acquisition modules, and the light-emitting channels are configured in a one-to-one correspondence. The light-emitting channel includes a switching element, a sampling resistor, and a light-emitting diode. The adjustable power supply is connected to the constant current chip in sequence through the switching element, the sampling resistor, and the light-emitting diode. The input terminal of the first signal acquisition module is connected in series between the switching element and the sampling resistor, the output terminal of the first signal acquisition module is connected to the first input terminal of the main control chip, and the first output terminal of the main control chip is connected to the control terminal of the switching element; the first input terminal, the first output terminal, and the switching element are configured in a one-to-one correspondence. One input terminal of the second signal acquisition module is connected in series between the sampling resistor and the light-emitting diode, and the other input terminal of the second signal acquisition module is connected in series between the light-emitting diode and the constant current chip; The output terminal of the second signal acquisition module is connected to the second input terminal of the main control chip, the second output terminal of the main control chip is connected to the input terminal of the power regulation feedback module, the output terminal of the power regulation feedback module is connected to the adjustable power supply, and the second input terminal is configured to correspond one-to-one with the second signal acquisition module.

[0007] In some embodiments, the first signal acquisition module includes: First resistor, second resistor, and first amplifier; The negative input terminal of the first amplifier is grounded through a first resistor, and the positive input terminal of the first amplifier is connected in series between the switching element and the sampling resistor. The second resistor is connected in parallel with the first amplifier, the first end of the second resistor is connected to the positive input terminal of the first amplifier, and the second end of the second resistor is connected to the output terminal of the first amplifier. The output terminal of the first amplifier is connected to the first input terminal of the main control chip.

[0008] In some embodiments, the second signal acquisition module includes: The third resistor, the fourth resistor, the fifth resistor, the sixth resistor, and the second amplifier; The first end of the third resistor is connected to the positive input terminal of the second amplifier, and the second end of the third resistor is connected in series between the sampling resistor and the light-emitting diode; the first end of the fourth resistor is connected in series between the third resistor and the positive input terminal of the second amplifier, and the second end of the fourth resistor is grounded. The first end of the fifth resistor is connected to the negative input terminal of the second amplifier, and the second end of the fifth resistor is connected in series between the light-emitting diode and the constant current chip; the first end of the sixth resistor is connected in series between the fifth resistor and the negative input terminal of the second amplifier, and the second end of the sixth resistor is grounded. The output of the second amplifier is connected to the second input of the main control chip.

[0009] In some embodiments, the power regulation feedback module includes: The seventh resistor, the eighth resistor, the ninth resistor, the tenth resistor, the eleventh resistor, the twelfth resistor, the thirteenth resistor, the first capacitor, the second capacitor, the third capacitor, inductors, transistors, and optocouplers; The power supply is grounded sequentially through the thirteenth resistor and the seventh resistor. The first end of the twelfth resistor is connected to the second output terminal of the main control chip. The second end of the twelfth resistor is connected in series between the thirteenth resistor and the seventh resistor to form a series connection node. The first end of the eighth resistor is connected in series between the series node and the thirteenth resistor; the second end of the eighth resistor is connected to the first end of the transistor, the first end of the ninth resistor and the first input end of the optocoupler through the second capacitor. The second terminal of the transistor is connected in series between the seventh resistor and the series connection node, and the third terminal of the transistor is grounded. The second end of the ninth resistor is connected to the first end of the tenth resistor and the first end of the inductor, the second end of the tenth resistor is connected to the second input end of the optocoupler, and the second end of the inductor is connected to the power supply. The first output terminal of the optocoupler is grounded through the eleventh resistor, and the second output terminal of the optocoupler is connected to the input terminal of the adjustable power supply; the first terminal of the three-electrode capacitor is connected in series between the second output terminal of the optocoupler and the input terminal of the adjustable power supply, and the second terminal of the three-electrode capacitor is grounded.

[0010] In some embodiments, the main control chip includes: The first signal output unit is connected to the first control unit; The first control unit includes multiple input terminals, which are connected one-to-one with the output terminals of each of the first signal acquisition modules; The first signal output unit includes multiple switch control output terminals, which are connected one-to-one with the control terminals of each of the switch elements.

[0011] In some embodiments, the main control chip further includes: The second signal output unit is connected to the second control unit; The second control unit includes multiple input terminals, which are connected one-to-one with the output terminals of each of the second signal acquisition modules; the second signal output unit includes a voltage regulation signal output terminal, which is connected to the power supply regulation feedback module.

[0012] In some embodiments, the switching element is a transistor element.

[0013] In some embodiments, the LED protection adjustment circuit further includes: The fourteenth resistor, the fifteenth resistor, and the fourth capacitor; The first output terminal is connected to the control terminal of the switching element through the fourteenth resistor; the fifteenth resistor and the fourth capacitor are connected in parallel, the first end of the fifteenth resistor and the first end of the fourth capacitor are both connected in series between the fourteenth resistor and the switching element, and the second end of the fifteenth resistor and the second end of the fourth capacitor are both grounded.

[0014] In some embodiments, the LED protection adjustment circuit includes: a sixteenth resistor and a fifth capacitor; The second output terminal is connected to the power regulation feedback module through the sixteenth resistor. The first terminal of the fifth capacitor is connected in series between the sixteenth resistor and the power regulation feedback module, and the second terminal of the fifth capacitor is grounded.

[0015] In a second aspect, the present invention also provides a light-emitting diode protection and adjustment system, including the light-emitting diode protection and adjustment circuit as described in the first aspect.

[0016] The technical solution provided by the embodiments of the present invention has the following advantages compared with the prior art: The LED protection and regulation circuit provided in this embodiment of the invention monitors the incoming current of the channel using a first signal acquisition module. This, combined with switching elements, enables independent hardware disconnection of a single-channel short-circuit fault, preventing the high current from burning out the constant current chip and power supply components. A second signal acquisition module acquires the actual forward voltage drop (VF) of the LED in each channel. The main control chip aggregates the VF values ​​of all channels and calculates the required supply voltage for normal LED illumination based on VF changes corresponding to LED temperature and aging degree. A power supply regulation feedback module then uses closed-loop control to dynamically adjust the output voltage of the adjustable power supply, dynamically adjusting the supply voltage to follow the actual LED voltage drop. This eliminates redundant voltage drop losses, significantly reduces static power consumption, and achieves dynamic energy saving throughout the circuit. Therefore, without modifying the constant current driver chip, independent fault detection, hardware isolation of faults, and adaptive adjustment of power supply for multiple LED paths can be achieved. Attached Figure Description

[0017] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, those skilled in the art can obtain other drawings based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of a light-emitting diode protection and adjustment circuit provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of a power regulation feedback module provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the structure of a main control chip provided in an embodiment of the present invention.

[0020] Among them, 10, adjustable power supply; 11, main control chip; 111, first control unit; 011, first signal output unit; 112, second control unit; 012, second signal output unit; 12, first signal acquisition module; 13, second signal acquisition module; 14, power supply regulation feedback module; 15, switching element; 16, constant current chip; R, sampling resistor; LED, light-emitting diode; R1, first resistor; R2, second resistor; R3, third resistor; R4, fourth resistor; R5, fifth resistor; R6, sixth resistor; R7, seventh resistor; R8, the first... Eight resistors; R9, ninth resistor; R10, tenth resistor; R11, eleventh resistor; R12, twelfth resistor; R13, thirteenth resistor; R14, fourteenth resistor; R15, fifteenth resistor; R16, sixteenth resistor; P1, first amplifier; P2, second amplifier; C1, first capacitor; C2, second capacitor; C3, third capacitor; C4, fourth capacitor; C5, fifth capacitor; L, inductor; TL, transistor; PC, optocoupler; A1, first input terminal; A2, second input terminal; B1, first output terminal; B2, second output terminal. Detailed Implementation

[0021] To better understand the above-mentioned objectives, features, and advantages of the present invention, the solutions of the present invention will be further described below. It should be noted that, unless otherwise specified, the embodiments of the present invention and the features thereof can be combined with each other.

[0022] Many specific details are set forth in the following description in order to provide a full understanding of the invention, but the invention may also be practiced in other ways different from those described herein; obviously, the embodiments in the specification are only some embodiments of the invention, and not all embodiments.

[0023] The LED protection and adjustment circuit and system provided in the embodiments of the present invention will be described exemplarily below with reference to the accompanying drawings.

[0024] Figure 1 This is a schematic diagram of a light-emitting diode protection and adjustment circuit provided in an embodiment of the present invention. Figure 1 As shown, the LED protection and adjustment circuit includes: an adjustable power supply 10, a main control chip 11, multiple first signal acquisition modules 12, multiple second signal acquisition modules 13, a constant current chip 16, a power supply adjustment feedback module 14, and multiple light-emitting channels; the first signal acquisition modules 12, the second signal acquisition modules 13, and the light-emitting channels are configured in a one-to-one correspondence. The light-emitting channel includes a switching element 15, a sampling resistor R, and a light-emitting diode LED. The adjustable power supply 10 is connected to the constant current chip 16 in sequence through the switching element 15, the sampling resistor R, and the light-emitting diode LED. The input terminal of the first signal acquisition module 12 is connected in series between the switching element 15 and the sampling resistor R. The output terminal of the first signal acquisition module 12 is connected to the first input terminal A1 of the main control chip 11. The first output terminal B1 of the main control chip 11 is connected to the control terminal of the switching element 15. The first input terminal A1, the first output terminal B1 and the switching element 15 are set in a one-to-one correspondence. One input terminal of the second signal acquisition module 13 is connected in series between the sampling resistor R and the light-emitting diode LED, and the other input terminal of the second signal acquisition module 13 is connected in series between the light-emitting diode LED and the constant current chip 16. The output terminal of the second signal acquisition module 13 is connected to the second input terminal A2 of the main control chip 11. The second output terminal B2 of the main control chip 11 is connected to the input terminal of the power regulation feedback module 14. The output terminal of the power regulation feedback module 14 is connected to the adjustable power supply 10. The second input terminal A2 and the second signal acquisition module 13 are set in a one-to-one correspondence.

[0025] Specifically, Figure 1 The example shows two sets of light-emitting channels, each set of light-emitting channels is equipped with a first signal acquisition module 12 and a second signal acquisition module 13 (only one set of light-emitting channels is shown in the figure). Thus, each signal acquisition loop is independent of each other, and multiple light-emitting channels can be expanded according to the number of channels on the display screen, without signal crosstalk between channels.

[0026] The light-emitting channel includes a switching element 15, a sampling resistor R, and a light-emitting diode (LED). An adjustable power supply 10 is electrically connected to a constant current chip 16 via the switching element 15, sampling resistor R, and LED. Specifically, the adjustable power supply 10 outputs a supply voltage that flows sequentially through the switching element 15, sampling resistor R, and LED, ultimately connecting to the constant current chip 16. The constant current chip 16 maintains the same current for each light-emitting channel, ensuring normal screen brightness. The switching element 15 acts as the on / off actuator for the light-emitting channel. The voltage signals corresponding to each sampling resistor R are acquired by the first signal acquisition module 12. This sampled signal, representing the operating current, is amplified by the first signal acquisition module 12 (including an amplifier as described below) and transmitted to the main control chip 11. Based on the acquired sampled signals, the main control chip 11 can determine the current status of the light-emitting channel, thereby enabling real-time monitoring of channel short-circuit, open-circuit, and overload high-current faults.

[0027] For example, under normal operation: the adjustable power supply 10 outputs 25mA, which is constant current through the constant current chip 16. The voltage of the sampling resistor R is 0.03V, which is increased to 1.8V after passing through the first signal acquisition module 12. Since it is between 0.1V and 2V, the switching element 15 is turned on, and the light-emitting diode LED lights up normally. The main control chip 11 determines that there is no fault in the channel based on the acquired signal.

[0028] Channel open circuit: The LED is disconnected, the loop current is 0, the sampling voltage is 0V, which is less than 0.1V. The main control chip 11 judges that there is an open circuit fault in the channel based on the acquired signal. At this time, it sends a control signal to the switching element 15 to control the switching element 15 to turn off within 1μs. Only the light-emitting channel is turned off, while other channels are normal.

[0029] Channel short circuit: The positive and negative terminals of the LED are stuck together, and the current surges to 500mA. The sampling voltage is 0.5V, which is amplified to 2.5V after being amplified by the first signal acquisition module 12. Since it is greater than 2V, the main control chip 11 determines that there is a short circuit fault in the channel based on the acquired signal. The switching element 15 quickly turns off, cutting off the large current and protecting the adjustable power supply 10 and the constant current chip 16.

[0030] Fault recovery: After replacing the LED, the current returned to 25mA, the control switch element 15 was turned on, and the channel returned to normal operation.

[0031] Each LED channel is equipped with an independent second signal acquisition module 13. Each second signal acquisition module 13 independently acquires the VF value of the LED in its own channel without interfering with each other. Each VF sampling signal is sent to the corresponding second input terminal A2 of the main control chip 11. The main control chip 11 can simultaneously acquire the VF values ​​of all LED channels.

[0032] The main control chip 11 calculates the power supply threshold required for normal LED illumination based on the VF values ​​of each LED collected in real time. If the VF of multiple LEDs is detected to be synchronously low (e.g., due to prolonged equipment operation, increased ambient temperature, or decreased voltage drop due to LED aging), the main control chip 11 outputs a voltage regulation signal through the second output terminal, which is input to the power supply regulation feedback module 14. The power supply regulation feedback module 14 then outputs a voltage regulation control signal Vfb to the adjustable power supply 10 to reduce the output voltage of the adjustable power supply 10 and reduce unnecessary power consumption in the circuit. If the VF of multiple LEDs is detected to be synchronously high (e.g., low temperature startup, brand new LEDs), the main control chip 11 controls the adjustable power supply 10 to increase the output voltage, ensuring that the LEDs have sufficient voltage difference to maintain normal operation and ensuring uniform screen brightness.

[0033] In the prior art, LED driver power supplies have a fixed high voltage output, with a large amount of redundant voltage reserved to adapt to the maximum value of VF across the entire temperature range and life cycle, resulting in long-term useless power loss. In the embodiment of the present invention, the second signal acquisition module 13 monitors VF in real time and dynamically adjusts the supply voltage according to the actual voltage drop of the LED, eliminating redundant voltage difference loss, significantly reducing the static power consumption of the circuit, and achieving dynamic energy saving throughout the process.

[0034] Therefore, this invention sets up a first signal acquisition module 12 to monitor the channel input current, and works with the switching element 15 to achieve independent hardware disconnection of a single channel short circuit fault, avoiding the burnout of the constant current chip 16 and power supply devices by the large short circuit current; a second signal acquisition module 13 is set up to obtain the actual forward voltage drop VF of the LED in the channel. The main control chip 11 summarizes the VF values ​​of all channels, calculates the supply voltage required for normal LED light emission based on the VF changes corresponding to LED temperature and aging degree, and dynamically adjusts the output voltage by using the power supply regulation feedback module 14 to control the adjustable power supply 10 in a closed loop, thereby dynamically adjusting the supply voltage according to the actual voltage drop of the LED, eliminating redundant voltage difference loss, significantly reducing the static power consumption of the circuit, and achieving dynamic energy saving throughout the process.

[0035] In some embodiments, such as Figure 1 As shown, the first signal acquisition module 12 includes: First resistor R1, second resistor R2, and first amplifier P1; The negative input terminal of the first amplifier P1 is grounded through the first resistor R1, and the positive input terminal of the first amplifier P1 is connected in series between the switching element 15 and the sampling resistor R. The second resistor R2 is connected in parallel with the first amplifier P1. The first end of the second resistor R2 is connected to the positive input terminal of the first amplifier P1, and the second end of the second resistor R2 is connected to the output terminal of the first amplifier P1. The output of the first amplifier P1 is connected to the first input A1 of the main control chip 11.

[0036] The first resistor R1 provides a stable ground reference potential to the negative input terminal of the first amplifier P1. The positive input terminal of the first amplifier P1 samples the node voltage between the switching element 15 and the sampling resistor R. This node voltage can directly reflect the real-time current magnitude of the channel. When a short-circuit fault occurs in the corresponding channel, the inrush current of the loop increases sharply, the voltage drop of the sampling resistor R increases synchronously, and the sampling node voltage changes rapidly. The first amplifier P1 can instantly capture the fault voltage characteristics.

[0037] The second resistor R2 and the first amplifier P1 form a voltage series negative feedback amplification circuit, which can amplify the weak voltage change signal at the channel input, improve the sensitivity of short-circuit fault detection, and facilitate the main control chip 11 to accurately identify minute current fluctuations. The sampled signal after being amplified by the first amplifier P1 is transmitted to the first input terminal A1 of the main control chip 11. The main control chip 11 has a preset overload voltage threshold and compares the sampled level in real time: if the sampled level does not exceed the preset overload voltage threshold, it is determined that the corresponding light-emitting channel is in normal working condition, and the main control chip 11 continuously outputs a conduction control signal to keep the switching element 15 closed; if the sampled level exceeds the preset overload voltage threshold, it is determined that the channel has a short circuit or overload fault, and the main control chip 11 immediately outputs a shutdown level through the corresponding first output terminal B1 to cut off the switching element 15 of that channel, thereby achieving hardware physical isolation of the faulty channel.

[0038] In some embodiments, such as Figure 1 As shown, the second signal acquisition module 13 includes: The third resistor R3, the fourth resistor R4, the fifth resistor R5, the sixth resistor R6, and the second amplifier P2; The first end of the third resistor R3 is connected to the positive input terminal of the second amplifier P2, and the second end of the third resistor R3 is connected in series between the sampling resistor R and the light-emitting diode LED; the first end of the fourth resistor R4 is connected in series between the third resistor R3 and the positive input terminal of the second amplifier P2, and the second end of the fourth resistor R4 is grounded. The first end of the fifth resistor R5 is connected to the negative input terminal of the second amplifier P2, and the second end of the fifth resistor R5 is connected in series between the light-emitting diode LED and the constant current chip 16; the first end of the sixth resistor R6 is connected in series between the fifth resistor R5 and the negative input terminal of the second amplifier P2, and the second end of the sixth resistor R6 is grounded. The output of the second amplifier P2 is connected to the second input A2 of the main control chip 11.

[0039] Therefore, the forward voltage drop VF across the LED can be acquired through the second signal acquisition module 13, which can provide voltage data to the main control chip 11 and drive the adjustable power supply 10 to dynamically adjust the voltage to achieve circuit energy saving.

[0040] In this system, the third resistor R3 and the fourth resistor R4 form the upper branch voltage divider acquisition network, and the fifth resistor R5 and the sixth resistor R6 form the lower branch voltage divider acquisition network. The upper branch voltage divider network acquires the potential at one end of the LED, and the lower branch voltage divider network acquires the potential at the other end of the LED. The second amplifier P2 performs a differential operation on the potentials at both ends of the LED, and the output voltage signal has a linear correspondence with the actual VF value of the LED. The true forward voltage drop of each LED can be obtained without complex calculations. Therefore, by obtaining the true forward voltage drop of the LED, the output voltage of the adjustable power supply 10 can be adjusted. For details on how to adjust it, please refer to the following text.

[0041] In some embodiments, Figure 2 This is a schematic diagram of a power regulation feedback module provided in an embodiment of the present invention. (Combined with...) Figure 1 and Figure 2 The power regulation feedback module 14 includes: The components are: seventh resistor R7, eighth resistor R8, ninth resistor R9, tenth resistor R10, eleventh resistor R11, twelfth resistor R12, thirteenth resistor R13, first capacitor C1, second capacitor C2, third capacitor C3, inductor L, transistor TL, and optocoupler PC. The power supply VCC is grounded through the thirteenth resistor R13 and the seventh resistor R7 in sequence. The first end of the twelfth resistor R12 is connected to the second output terminal of the main control chip 11. The second end of the twelfth resistor R12 is connected in series between the thirteenth resistor R13 and the seventh resistor R7 to form a series connection node O. The first end of the eighth resistor R8 is connected in series between the series node O and the thirteenth resistor R13; the second end of the eighth resistor R8 is connected to the first end of the transistor TL, the first end of the ninth resistor R9, and the first input terminal A1 of the optocoupler PC through the second capacitor C2. The second terminal of transistor TL is connected in series between the seventh resistor R7 and the series connection node, and the third terminal of transistor TL is grounded. The second end of the ninth resistor R9 is connected to the first end of the tenth resistor R10 and the first end of the inductor L, respectively. The second end of the tenth resistor R10 is connected to the second input terminal A2 of the optocoupler PC, and the second end of the inductor L is connected to the power supply. The first output terminal B1 of the optocoupler PC is grounded through the eleventh resistor R11, and the second output terminal of the optocoupler PC is connected to the input terminal of the adjustable power supply 10; the first terminal of the three-electrode capacitor is connected in series between the second output terminal of the optocoupler PC and the input terminal of the adjustable power supply 10, and the second terminal of the three-electrode capacitor is grounded.

[0042] Specifically, the power supply regulation feedback module 14 is an isolated closed-loop voltage regulation unit between the main control chip 11 and the adjustable power supply 10. It receives the voltage regulation signal output by the main control chip 11, converts the voltage regulation signal into a voltage regulation control signal Vfb and outputs it to the adjustable power supply 10, thereby realizing the dynamic adjustment of the output voltage of the adjustable power supply 10 according to the real-time VF of the LED.

[0043] Among them, the thirteenth resistor R13 and the seventh resistor R7 divide the power supply VCC to generate a fixed DC reference voltage, which provides a potential reference for the voltage regulation signal output by the main control chip 11; the voltage regulation signal output by the main control chip 11 is superimposed on the series node O through the twelfth resistor R12.

[0044] The eighth resistor R8 and the second capacitor C2 form a low-pass filter. After being connected in series with the voltage regulation signal that changes at the node, it is input to one end (control terminal) of the transistor TL. The transistor TL adjusts its own conduction current linearly according to the potential.

[0045] The optocoupler PC integrates a light-emitting diode (LED) and a phototransistor. Changes in the on-current of the transistor TL alter the brightness of the LED within the optocoupler PC. Higher LED brightness results in lower on-resistance of the phototransistor and a lower output Vfb potential; conversely, lower LED brightness leads to higher on-resistance and a higher output Vfb potential. This Vfb potential is output to the adjustable power supply 10, allowing it to dynamically adjust the output voltage to the light-emitting channel based on the Vfb potential.

[0046] In this circuit, the inductor L draws power from the power supply VCC and, together with the ninth resistor R9 and the tenth resistor R10, provides a stable driving current for the light-emitting diode (LED) in the optocoupler PC, preventing sudden changes in the light-emitting current caused by power supply fluctuations.

[0047] Among them, the eleventh resistor R11 is the current-limiting resistor for the phototube discharge, and the third capacitor C3 filters out the spike noise at the Vfb terminal, ensuring that the voltage regulation action of the adjustable power supply 10 is smooth and there will be no frequent voltage jumps.

[0048] Among them, the first capacitor C1 is a filter capacitor, which can filter out interference signals when a signal is input to the transistor TL.

[0049] In some embodiments, Figure 3 This is a schematic diagram of the structure of a main control chip provided in an embodiment of the present invention. Figure 1 and Figure 3 As shown, the main control chip 11 includes: a first control unit 111 and a first signal output unit 011 connected to the first control unit 111; The first control unit 111 includes multiple input terminals, which are connected one-to-one with the output terminals of each first signal acquisition module 12; The first signal output unit 011 includes multiple switch control output terminals, which are connected one-to-one with the control terminals of each switch element 15.

[0050] Specifically, each first signal acquisition module 12 acquires the input voltage between the corresponding LED channel switching element 15 and the sampling resistor R in real time, and after being amplified by the internal first amplifier P1, the sampled level is transmitted to the corresponding input terminal of the first control unit 111. The first control unit 111 can have built-in voltage threshold discrimination logic to compare the received level with the preset short-circuit overload threshold in real time.

[0051] When the sampling level is lower than the preset overload threshold: the first control unit 111 determines that the LED load and line condition of the channel are normal, and continuously outputs the conduction control level to the paired first signal output unit 011. The switching element 15 closes, and the corresponding LED channel is powered on and illuminates normally. When the sampling level exceeds the preset overload threshold, the first control unit 111 determines that the channel has a short circuit or overload fault, and immediately outputs a shutdown control level to the paired first signal output unit 011. The switching element 15 quickly disconnects, physically cutting off the faulty channel from the adjustable power supply 10 bus, thus preventing the short circuit high current from burning out the constant current chip 16 and the power supply device.

[0052] In some embodiments, continue as follows Figure 1 and Figure 3 As shown, the main control chip 11 also includes: The second control unit 112 is connected to the second signal output unit 012; The second control unit 112 includes multiple input terminals, which are connected one-to-one with the output terminals of each of the second signal acquisition modules 13; the second signal output unit 012 includes a voltage regulation signal output terminal, which is connected to the power supply regulation feedback module 14.

[0053] Specifically, the second control unit 112 is equipped with multiple input terminals, which are connected to the output terminals of each of the second signal acquisition modules 13. After each second signal acquisition module 13 acquires the forward voltage drop (VF) signal of the corresponding light-emitting channel, it directly inputs it to the corresponding input terminal of the second control unit 112, which can simultaneously acquire the real-time VF parameters of all channels of LEDs. After the VF data acquired from all channels is uniformly calculated and summarized by the second control unit 112, a voltage regulation signal is generated and output to the power supply regulation feedback module 14.

[0054] It should be noted that synchronously acquiring the real-time VF parameters of all LED channels can remove abnormal values ​​caused by faults such as short circuits, leaving only the normal values. The average value of these normal values ​​is then calculated. Since the LEDs in each channel are of the same model, their normal values ​​are similar, so the average value can reflect the actual operating condition of each LED channel.

[0055] In some embodiments, such as Figure 1 As shown, the switching element 15 is a transistor element. Specifically, the switching element 15 is selected from transistor elements such as MOSFETs. The MOSFETs serve as independent switching actuators for each light-emitting channel, and are connected in series between the adjustable power supply 10 and the sampling resistor R. They are individually driven by the main control chip 11 to achieve hardware isolation of fault channels.

[0056] In some embodiments, such as Figure 1 As shown, the LED protection and adjustment circuit also includes: The fourteenth resistor R14, the fifteenth resistor R15, and the fourth capacitor C4; The first output terminal B1 is connected to the control terminal of the switching element 15 through the fourteenth resistor R14; the fifteenth resistor R15 and the fourth capacitor C4 are connected in parallel, the first end of the fifteenth resistor R15 and the first end of the fourth capacitor C4 are both connected in series between the fourteenth resistor R14 and the switching element 15, and the second end of the fifteenth resistor R15 and the second end of the fourth capacitor C4 are both grounded.

[0057] Specifically, the fourteenth resistor R14, the fifteenth resistor R15, and the fourth capacitor C4 form an RC drive buffer circuit, which is located between the first output terminal B1 of the main control chip 11 and the control terminal of the switching element 15. This circuit is used to optimize the switch drive level, suppress electromagnetic interference, and prevent the switching element 15 from malfunctioning.

[0058] In some embodiments, such as Figure 1 As shown, the LED protection and adjustment circuit includes: the sixteenth resistor R16 and the fifth capacitor C5; The second output terminal is connected to the power regulation feedback module 14 through the sixteenth resistor R16. The first end of the fifth capacitor C5 is connected in series between the sixteenth resistor R16 and the power regulation feedback module 14, and the second end of the fifth capacitor C5 is grounded.

[0059] Specifically, the sixteenth resistor R16 and the fifth capacitor C5 are set to form an RC buffer filter circuit, which is set between the second output terminal of the main control chip 11 and the power regulation feedback module 14 to filter out high-frequency electromagnetic interference and ensure that the dynamic energy-saving voltage regulation process is stable and without fluctuations.

[0060] Based on the above embodiments, the present invention also provides a light-emitting diode protection and adjustment system, including the light-emitting diode protection and adjustment circuit as described in the above embodiments, and therefore has the same or similar beneficial effects, which will not be repeated here.

[0061] The terms “comprising,” “including,” or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0062] The above description is merely a preferred embodiment of the present invention and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention is not limited to the specific combination of the above-described technical features, but also includes other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the foregoing inventive concept. For example, technical solutions formed by substituting the above-described features with (but not limited to) technical features with similar functions as those in the present invention.

Claims

1. A light-emitting diode protection and adjustment circuit, characterized in that, include: Adjustable power supply, main control chip, multiple first signal acquisition modules, multiple second signal acquisition modules, constant current chip, power regulation feedback module and multiple light emission channels; The first signal acquisition module, the second signal acquisition module, and the light emission channel are configured in a one-to-one correspondence. The light-emitting channel includes a switching element, a sampling resistor, and a light-emitting diode. The adjustable power supply is connected to the constant current chip in sequence through the switching element, the sampling resistor, and the light-emitting diode. The input terminal of the first signal acquisition module is connected in series between the switching element and the sampling resistor, the output terminal of the first signal acquisition module is connected to the first input terminal of the main control chip, and the first output terminal of the main control chip is connected to the control terminal of the switching element; the first input terminal, the first output terminal, and the switching element are configured in a one-to-one correspondence. One input terminal of the second signal acquisition module is connected in series between the sampling resistor and the light-emitting diode, and the other input terminal of the second signal acquisition module is connected in series between the light-emitting diode and the constant current chip; The output terminal of the second signal acquisition module is connected to the second input terminal of the main control chip, the second output terminal of the main control chip is connected to the input terminal of the power regulation feedback module, the output terminal of the power regulation feedback module is connected to the adjustable power supply, and the second input terminal of the main control chip is configured to correspond one-to-one with the second signal acquisition module.

2. The LED protection and adjustment circuit according to claim 1, characterized in that, The first signal acquisition module includes: First resistor, second resistor, and first amplifier; The negative input terminal of the first amplifier is grounded through a first resistor, and the positive input terminal of the first amplifier is connected in series between the switching element and the sampling resistor. The second resistor is connected in parallel with the first amplifier, the first end of the second resistor is connected to the positive input terminal of the first amplifier, and the second end of the second resistor is connected to the output terminal of the first amplifier. The output terminal of the first amplifier is connected to the first input terminal of the main control chip.

3. The LED protection and adjustment circuit according to claim 1, characterized in that, The second signal acquisition module includes: The third resistor, the fourth resistor, the fifth resistor, the sixth resistor, and the second amplifier; The first end of the third resistor is connected to the positive input terminal of the second amplifier, and the second end of the third resistor is connected in series between the sampling resistor and the light-emitting diode; the first end of the fourth resistor is connected in series between the third resistor and the positive input terminal of the second amplifier, and the second end of the fourth resistor is grounded. The first end of the fifth resistor is connected to the negative input terminal of the second amplifier, and the second end of the fifth resistor is connected in series between the light-emitting diode and the constant current chip; the first end of the sixth resistor is connected in series between the fifth resistor and the negative input terminal of the second amplifier, and the second end of the sixth resistor is grounded. The output of the second amplifier is connected to the second input of the main control chip.

4. The LED protection and adjustment circuit according to claim 1, characterized in that, The power regulation feedback module includes: The seventh resistor, the eighth resistor, the ninth resistor, the tenth resistor, the eleventh resistor, the twelfth resistor, the thirteenth resistor, the first capacitor, the second capacitor, the third capacitor, inductors, transistors, and optocouplers; The power supply is grounded sequentially through the thirteenth resistor and the seventh resistor. The first end of the twelfth resistor is connected to the second output terminal of the main control chip. The second end of the twelfth resistor is connected in series between the thirteenth resistor and the seventh resistor to form a series connection node. The first end of the eighth resistor is connected in series between the series node and the thirteenth resistor; the second end of the eighth resistor is connected to the first end of the transistor, the first end of the ninth resistor and the first input end of the optocoupler through the second capacitor. The second terminal of the transistor is connected in series between the seventh resistor and the series connection node, and the third terminal of the transistor is grounded. The second end of the ninth resistor is connected to the first end of the tenth resistor and the first end of the inductor, the second end of the tenth resistor is connected to the second input end of the optocoupler, and the second end of the inductor is connected to the power supply. The first output terminal of the optocoupler is grounded through the eleventh resistor, and the second output terminal of the optocoupler is connected to the input terminal of the adjustable power supply; the first terminal of the three-electrode capacitor is connected in series between the second output terminal of the optocoupler and the input terminal of the adjustable power supply, and the second terminal of the three-electrode capacitor is grounded.

5. The LED protection and adjustment circuit according to claim 1, characterized in that, The main control chip includes: The first signal output unit is connected to the first control unit; The first control unit includes multiple input terminals, which are connected one-to-one with the output terminals of each of the first signal acquisition modules; The first signal output unit includes multiple switch control output terminals, which are connected one-to-one with the control terminals of each of the switch elements.

6. The LED protection and adjustment circuit according to claim 1, characterized in that, The main control chip also includes: The second signal output unit is connected to the second control unit; The second control unit includes multiple input terminals, which are connected one-to-one with the output terminals of each of the second signal acquisition modules; the second signal output unit includes a voltage regulation signal output terminal, which is connected to the power supply regulation feedback module.

7. The LED protection and adjustment circuit according to claim 1, characterized in that, The switching element is a transistor element.

8. The LED protection and adjustment circuit according to claim 1, characterized in that, Also includes: The fourteenth resistor, the fifteenth resistor, and the fourth capacitor; The first output terminal is connected to the control terminal of the switching element through the fourteenth resistor; The fifteenth resistor and the fourth capacitor are connected in parallel. The first end of the fifteenth resistor and the first end of the fourth capacitor are both connected in series between the fourteenth resistor and the switching element. The second end of the fifteenth resistor and the second end of the fourth capacitor are both grounded.

9. The LED protection and adjustment circuit according to claim 1, characterized in that, include: The sixteenth resistor and the fifth capacitor; The second output terminal is connected to the power regulation feedback module through the sixteenth resistor. The first terminal of the fifth capacitor is connected in series between the sixteenth resistor and the power regulation feedback module, and the second terminal of the fifth capacitor is grounded.

10. A light-emitting diode protection and adjustment system, characterized in that, Includes the LED protection and adjustment circuit as described in any one of claims 1-9.

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