Power supply processing circuit and LED system

Abstract

The utility model relates to the technical field of power supplies, in particular to a power supply processing circuit and an LED system, which comprise a control module, a power factor correction module and a resonance module. The control module is respectively connected with the power factor correction module and the resonance module, the power factor correction module is connected with the resonance module, the power factor correction module is also used for being connected with a power supply, and the resonance module is also used for being connected with an LED display screen. The control module is used for detecting alternating current output by the power supply and controlling the power factor correction module based on the alternating current so as to enable the power factor correction module to output preset voltage; and outputting the control signal to the resonance module to enable the resonance module to process the preset voltage based on the control signal so as to provide the target power for the LED display screen. Therefore, the target power can be output, the circuit loss can be reduced, and the output efficiency can be improved.

Description

[Technical field]

[0001] The utility model relates to the technical field of power supply, and in particular to a power supply processing circuit and an LED system. [Background technology]

[0002] Nowadays, the density of LED display products is getting higher and higher, and the product size is getting thinner and thinner. Mini / Micro LED is hailed as the next generation of display technology, which has the advantages of a wide range of applications and strong growth momentum. However, as the pixels of LED displays increase, the power of the cabinet is gradually increasing, and the cabinet is becoming thinner and thinner, and the requirements for LED power supply are also increasing.

[0003] At present, the power supply of new high-density LED large screens often adopts low voltage derating, that is, when AC170-264V input, the power supply outputs full power, and when AC90V-170V input, the power supply reduces the rated output to only 70%-80% of the full power. This leads to a significant reduction in the performance of the LED display when in use, and its advantages cannot be reflected. Moreover, after the power supply is made thinner, it cannot get good heat dissipation treatment, and the life of the internal components of the power supply is reduced due to high temperature, and the reliability and quality cannot be guaranteed. [Utility Model Content]

[0004] The embodiments of the utility model provide a power processing circuit and an LED system, aiming to solve the technical problems of low AC voltage power supply, poor efficiency and poor heat dissipation performance in the prior art.

[0005] In order to solve the above technical problems, a technical solution adopted by the embodiment of the utility model is: providing a power processing circuit, the power processing circuit includes a control module, a power factor correction module and a resonance module;

[0006] The control module is connected to the power factor correction module and the resonance module respectively, the power factor correction module is connected to the resonance module, the power factor correction module is also used to connect to a power source, and the resonance module is also used to connect to an LED display screen;

[0007] The control module is used to detect the alternating current output by the power supply, and control the power factor correction module based on the alternating current, so that the power factor correction module outputs a preset voltage; and

[0008] A control signal is output to the resonance module, so that the resonance module processes the preset voltage based on the control signal to provide target power for the LED display.

[0009] Optionally, the power correction factor module includes an inductor L100, a controller U100, a switch tube Q3, a resistor R108, a resistor R110 and a resistor R121;

[0010] The input end of the controller U100 is connected to the control module, the high-level output end of the controller U100 is connected to the control end of the switch tube Q3 through the resistor R108, the low-level output end of the controller U100 is connected to the control end of the switch tube Q3 through the resistor R110, the control end of the switch tube Q3 is also connected to the second end of the switch tube Q3 through the resistor R121, and the first end of the switch tube Q3 is connected to the power supply and control module through the inductor L100.

[0011] Optionally, the resonance module includes an LLC resonance unit and a synchronous rectification unit;

[0012] The control end of the LLC resonance unit is connected to the control module, the input end of the LLC resonance unit is connected to the power factor correction module, and the output end of the LLC resonance unit is connected to the LED display screen through the synchronous rectification unit;

[0013] The LLC resonance unit is used to receive the preset voltage and adjust the preset voltage to output a current signal;

[0014] The synchronous rectification unit is used to detect the current signal output by the LLC resonance unit, and adjust the reference voltage based on the current signal to adjust the magnitude of the current signal output by the LLC resonance unit.

[0015] Optionally, the LLC resonance unit includes a switch tube Q4, a switch tube Q5, a transformer T100, a diode D103, a diode D104, a resistor R124, a resistor R127, an inductor L102 and a capacitor EC101;

[0016] The control end of the switch tube Q4 is connected to the control module through the resistor R124, the first end of the switch tube Q1 is connected to the power factor correction module, the second end of the switch tube Q4 is respectively connected to the second end of the transformer T100 and the first end of the switch tube Q5, the control end of the switch tube Q5 is connected to the control module through the resistor R127, the first end of the transformer T100 is used for grounding, the third end of the transformer T100 is connected to the power factor correction module through the diode D103, the fifth end and the seventh end of the transformer T100 are connected to the second end of the capacitor EC101 through the synchronous rectification unit, and the sixth end of the transformer T100 is connected to the first end of the capacitor EC101 through the inductor L102.

[0017] Optionally, the synchronous rectification unit includes a switch tube Q103, a switch tube Q109, a controller U101, a controller U102, a resistor R109 and a resistor R119;

[0018] The first end of the switch tube Q103 is respectively connected to the chip selection end of the controller U101 and the fifth end of the transformer T100, the control end of the switch tube Q103 is connected to the driving pulse end of the controller U101, and the control end of the switch tube Q103 is also connected to the second end of the switch tube Q103 and the second end of the capacitor EC101 through the resistor R109, the first end of the switch tube Q109 is respectively connected to the chip selection end of the controller U102 and the seventh end of the transformer T100, the control end of the switch tube Q109 is connected to the driving pulse end of the controller U102, and the control end of the switch tube Q109 is also connected to the second end of the switch tube Q109 and the second end of the capacitor EC101 through the resistor R119.

[0019] Optionally, the switch tube Q3, the switch tube Q4, the switch tube Q5, the switch tube Q103 and the switch tube Q109 are all super junction field effect tubes.

[0020] Optionally, the power processing circuit further includes a surge protection module, wherein the surge protection module includes a thermistor RT100, a varistor RV100, a capacitor CY100, an inductor L101, and a rectifier bridge D102;

[0021] The two ends of the varistor RV100 are respectively connected to the live wire and the neutral wire of the power supply, the varistor RV100 is also connected to the ground wire of the power supply through the capacitor CY100, the thermistor RT100 is respectively connected to the neutral wire of the power supply and the first end of the inductor L101, the fourth end of the inductor L101 is connected to the live wire of the power supply, the second end and the third end of the inductor L101 are respectively connected to the rectifier bridge D102, and the rectifier bridge D102 is also connected to the power factor correction module.

[0022] Optionally, the power processing circuit further includes an overcurrent protection module, and the overcurrent protection module includes a resistor R125, a resistor RS100 and a capacitor C104;

[0023] The resistor RS100 is connected to the power supply and the ground terminal respectively, the resistor R125 is connected in series with the capacitor C104, and the resistor R125 and the capacitor C104 are also connected in parallel with the resistor RS100.

[0024] Optionally, the power processing circuit further includes an output overvoltage protection module, and the output overvoltage protection module includes a switch tube Q107, a switch tube Q108, a resistor R112, a controller U103 and a complementary transistor Q106;

[0025] The complementary triode Q106 is connected to the control module and the controller U103 respectively, the output end of the controller U103 is connected to the control end of the switch tube Q107 and the control end of the switch tube Q108 respectively, the first ends of the switch tube Q107 and the switch tube 108 are connected to the resonance module respectively, the first ends of the switch tube Q107 and the switch tube 108 are also connected to the output end of the controller U103 through the resistor R112, the second ends of the switch tube Q107 and the switch tube 108 are also connected to the complementary triode Q106, and the second ends of the switch tube Q107 and the switch tube 108 are also used to connect to the LED display screen.

[0026] In order to solve the above technical problems, another technical solution adopted by the embodiment of the utility model is: to provide an LED system, the LED system comprising:

[0027] power supply;

[0028] LED display screen; and

[0029] A power processing circuit as described above.

[0030] Different from the related art, the embodiment of the utility model provides a power processing circuit and an LED system, the power processing circuit includes a control module, a power factor correction module and a resonance module; the control module is connected to the power factor correction module and the resonance module respectively, the power factor correction module is connected to the resonance module, the power factor correction module is also used to connect to the power supply, and the resonance module is also used to connect to the LED display. The control module is used to detect the alternating current output by the power supply, and control the power factor correction module based on the alternating current so that the power factor correction module outputs a preset voltage. Based on this, when a small voltage is input, the power factor correction module is used to boost the voltage, so that when providing the target power, only the voltage reduction operation is required, thereby avoiding the addition of redundant devices and improving the output efficiency. And output a control signal to the resonance module, so that the resonance module processes the preset voltage based on the control signal to provide the target power for the LED display. Based on this, the heat generation of the device can be reduced while reducing the loss.

Brief Description of the Drawings

[0031] One or more embodiments are exemplarily described by corresponding drawings, which do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings represent similar elements, and the figures in the drawings do not constitute proportional limitations unless otherwise stated.

[0032] Figure 1 It is a structural block diagram of an LED system provided by an embodiment of the utility model;

[0033] Figure 2 It is a structural block diagram of a power processing circuit provided by an embodiment of the utility model;

[0034] Figure 3 It is a circuit diagram of a power factor correction module provided by an embodiment of the utility model;

[0035] Figure 4a-4c is a circuit diagram of a resonance module provided by an embodiment of the utility model;

[0036] Figure 5 is a circuit diagram of a control module provided by an embodiment of the utility model;

[0037] Figure 6 It is a circuit diagram of a current sharing circuit provided by an embodiment of the utility model;

[0038] Figure 7 is a circuit diagram of a loop control circuit provided by an embodiment of the utility model;

[0039] Figure 8 It is a circuit diagram of a protection circuit provided by an embodiment of the utility model. [Specific implementation method]

[0040] In order to make the purpose, technical solution and advantages of the utility model more clear, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0041] The technical features involved in the various embodiments of the present application described below do not conflict with each other and can be combined with each other.

[0042] When an element is referred to as being “connected to” another element, it can be directly connected to the other element, or one or more intervening elements may be present therebetween.

[0043] The terms "first", "second", etc. in the specification and claims of the present utility model are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described herein, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more.

[0044] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as those commonly understood by those skilled in the art in the technical field of the present invention. The terms used in the specification of the present invention are only for the purpose of describing specific embodiments and are not used to limit the present invention. The term "and / or" used in this specification includes any and all combinations of one or more related listed items.

[0045] See also Figure 1 , Figure 1 is a structural block diagram of an LED system provided by an embodiment of the utility model, such as Figure 1 As shown, the LED system 1 includes a power supply 100, an LED display screen 200 and a power supply processing circuit 300; the power supply processing circuit 300 is connected to the power supply 100 and the LED display screen 200 respectively. The power supply processing circuit 300 is used to receive the alternating current output by the power supply 100, process the alternating current, and finally output the processed alternating current to the LED display screen 200 to provide the target power for the LED display screen 200. Optionally, the target power is 200W.

[0046] See also Figure 2 , Figure 2 is a structural block diagram of a power processing circuit provided by an embodiment of the utility model, such as Figure 2 As shown, the control module 31, the power factor correction module 32 and the resonance module 33 are included. The control module 31 is connected to the power factor correction module 32 and the resonance module 33 respectively, the power factor correction module 32 is connected to the resonance module 33, the power factor correction module 32 is also used to connect to the power supply 100, and the resonance module 33 is also used to connect to the LED display screen 200.

[0047] The control module 31 is used to detect the alternating current output by the power supply 100, and control the power factor correction module 32 based on the alternating current, so that the power factor correction module 32 outputs a preset voltage; and

[0048] A control signal is output to the resonance module 33 , so that the resonance module 33 processes the preset voltage based on the control signal to provide target power for the LED display screen 200 .

[0049] It should be noted that when the power supply 100 outputs AC power to the power factor correction module 32, the control module 31 will determine the size of the input AC power. If the AC power is greater than the first preset threshold or less than the second preset threshold, the control module 31 will control the power factor correction module 32 to work in BCM mode (Boundary-Current-Mode, critical conduction mode), wherein the critical conduction mode means that the control module 31 will monitor the current of the power factor correction module 32 in real time, and when the current is detected to be 0, turn off the conduction of the power factor correction module 32 until there is current in the power factor correction module 32, and then control the power factor correction module 32 to conduct. If the AC point is less than the first preset threshold and greater than the second preset threshold, the power factor correction module 32 is controlled to work in CCM mode (Continuous Conduction Mode, continuous conduction mode), wherein the continuous conduction mode means that during the operation of the power factor correction module 32, the current of the power factor correction module 32 will never reach 0. It should be noted that the first preset threshold is greater than the second preset threshold.

[0050] For details, please refer to Figure 3 , Figure 3 is a circuit diagram of a power factor correction module provided by an embodiment of the utility model, such as Figure 3As shown, the power factor correction module 32 includes an inductor L100, a controller U100, a switch tube Q3, a resistor R108, a resistor R110 and a resistor R121; the input end of the controller U100 is connected to the control module 31, the high-level output end of the controller U100 is connected to the control end of the switch tube Q3 through the resistor R108, the low-level output end of the controller U100 is connected to the control end of the switch tube Q3 through the resistor R110, the control end of the switch tube Q3 is also connected to the second end of the switch tube Q3 through the resistor R121, and the first end of the switch tube Q3 is connected to the power supply 100 and the control module 31 through the inductor L100. Among them, when the power supply 100 outputs AC power, the AC power will flow into the inductor L100. At this time, the control module 31 will detect the AC power and output a driving signal to the second pin of the U100 based on the detected AC power. When the second pin of the U100 receives the driving signal, the driving signal will be amplified and the amplified driving signal will be output through the fifth pin or the sixth pin to control the on and off of the switch tube Q3, thereby controlling the current on the inductor L100, and then outputting a preset voltage to the resonance module 33. Based on this, the working mode of the switch tube Q3 can be controlled by the AC power output by the power supply 100, thereby adjusting the current on the inductor L100, so as to achieve boosting of small current input and direct output when large current input.

[0051] It can be known that when the power factor correction module 32 works in the BCM mode, the smaller the inductance of the inductor L100, the higher the switching frequency of the switch tube Q3, based on which the volume of the inductor L100 can be reduced. And by continuously detecting the size of the alternating current to control the power factor correction module 32 to work in the BCM mode or the CCM mode, it can not only increase the reliability of the circuit and reduce the heat generated by the power supply 100, but also reduce the peak current of the inductor L100, avoid the inductor L100 from entering saturation, reduce the switch damage of the switch tube Q3, and improve the efficiency of the circuit.

[0052] In some embodiments, the inductor L100 adopts the design of a flat line common mode inductor, and on the basis of the flat line common mode inductor, a high-performance magnetic sheet is added and placed between the windings of the flat common mode inductor, thereby controlling the height of the inductor L100 within 9 mm.

[0053] In some embodiments, Figure 3 As shown, the power factor correction module 32 further includes a diode D5, and the diode D5 is respectively connected to the second end of the inductor L100 and the resonance module 33. The diode D5 is a semiconductor silicon carbide diode device.

[0054] In some embodiments, the power processing circuit 300 further includes a surge protection module 34 (not shown), wherein Figure 3 As shown, the surge protection module 34 includes a thermistor RT100, a varistor RV100, a capacitor CY100, an inductor L101, and a rectifier bridge D102;

[0055] The two ends of the varistor RV100 are respectively connected to the live wire and the neutral wire of the power supply 100, the varistor RV100 is also connected to the ground wire of the power supply 100 through the capacitor CY100, the thermistor RT100 is respectively connected to the neutral wire of the power supply 100 and the first end of the inductor L101, the fourth end of the inductor L101 is connected to the live wire of the power supply 100, the second end and the third end of the inductor L101 are respectively connected to the rectifier bridge D102, the second end and the third end of the inductor L101 are also respectively connected to the control module 31, and the rectifier bridge D102 is also connected to the power factor correction module 32. It should be noted that the varistor RV100 is used to clamp the surge voltage to protect the subsequent circuit, and the thermistor RT100 is a resistor with a negative temperature coefficient, which is mainly used to reduce the input surge current when the machine is turned on and off, thereby reducing the impact on the subsequent devices.

[0056] In another embodiment, the power processing circuit further includes an overcurrent protection module 35 (not shown), wherein Figure 3 As shown, the overcurrent protection module 35 includes a resistor R125, a resistor RS100 and a capacitor C104; the resistor RS100 is connected to the power supply 100 and the ground terminal respectively, the resistor R125 is connected in series with the capacitor C104, and the resistor R125 and the capacitor C104 are also connected in parallel with the resistor RS100. Specifically, when the current output by the rectifier bridge D102 is greater than the preset current, the current will pass through the resistor RS100 and the resistor R125 output value to simulate the ground, so as to discharge the current, thereby protecting the current impact of subsequent devices.

[0057] Further, such as Figure 2 The resonance module 33 further includes an LLC resonance unit 331 and a synchronous rectification unit 332; the control end of the LLC resonance unit 331 is connected to the control module 31, the input end of the LLC resonance unit 331 is connected to the power factor correction module 32, and the output end of the LLC resonance unit 331 is connected to the LED display screen 200 through the synchronous rectification unit 332;

[0058] The LLC resonance unit 331 is used to receive the preset voltage and adjust the preset voltage to output a current signal;

[0059] The synchronous rectification unit 332 is used to detect the current signal output by the LLC resonance unit 331 , and adjust the reference voltage based on the current signal to adjust the magnitude of the current signal output by the LLC resonance unit 331 .

[0060] For details, please refer to Figure 4a-4c , Figure 4a-4c is a circuit diagram of a resonance module provided by an embodiment of the utility model, such as Figure 4a As shown, the LLC resonant unit 331 includes a switch tube Q4, a switch tube Q5, a transformer T100, a diode D103, a diode D104, a resistor R124, a resistor R127, an inductor L102 and a capacitor EC101; the control end of the switch tube Q4 is connected to the control module 31 through the resistor R124, the first end of the switch tube Q1 is connected to the power factor correction module 32, and the second end of the switch tube Q4 is respectively connected to the second end of the transformer T100 and the first end of the switch tube Q5. The control end of the switch tube Q5 is connected to the control module 31 through the resistor R127, the first end of the transformer T100 is used for grounding, the third end of the transformer T100 is connected to the power factor correction module 32 through the diode D103, the fifth end and the seventh end of the transformer T100 are connected to the second end of the capacitor EC101 through the synchronous rectification unit 332, and the sixth end of the transformer T100 is connected to the first end of the capacitor EC101 through the inductor L102. Wherein, when the power factor correction module 32 outputs the preset voltage, the control module 31 will send control signals to the switch tube Q4 and the switch tube Q5 respectively to control the soft start of the switch tube Q4 and the switch tube Q5. When the switch tube Q4 and the switch tube Q5 are started, the transformer T100, the inductor L102, and the capacitor EC101 start to resonate, and then output the preset power to the LED display screen 200. It should be noted that the inductor L102 is arranged on the secondary side of the transformer T100, which can not only participate in the resonance, but also serve as an output filter inductor to reduce the output capacitor ripple current. And after the inductor L102 is used as the filter inductor, when selecting the capacitor EC101, a small and low-capacity capacitor can be selected, so as to reduce the height while meeting the current filtering requirements. Optionally, the voltage range of the LLC resonance unit 331 output is 3.8V-5V adjustable, and the current is a large current of 40A. Based on this, the LED display screen 200 can be provided with a power of 152W-200W.

[0061] It should be noted that, since the inductor L102 is on the secondary side of the transformer T100, the output of the inductor L102 is low voltage and high current. When there is loss in the output, the efficiency of the power processing circuit 300 will also decrease, and the loss will be manifested in the form of heat, thereby reducing the reliability and life of the power processing circuit 300. Based on this, a synchronous rectification circuit is designed to rectify the current output by the inductor L102, and the high-frequency AC output by the inductor L102 is rectified into DC, thereby reducing output loss and improving the reliability of the power processing circuit 300. Specifically, as Figure 4a-4c As shown, the synchronous rectification unit 332 includes a switch tube Q103, a switch tube Q109, a controller U101, a controller U102, a resistor R109 and a resistor R119;

[0062] The first end of the switch tube Q103 is respectively connected to the chip selection end of the controller U101 and the fifth end of the transformer T100, the control end of the switch tube Q103 is connected to the driving pulse end of the controller U101, and the control end of the switch tube Q103 is also connected to the second end of the switch tube Q103 and the second end of the capacitor EC101 through the resistor R109, the first end of the switch tube Q109 is respectively connected to the chip selection end of the controller U102 and the seventh end of the transformer T100, the control end of the switch tube Q109 is connected to the driving pulse end of the controller U102, and the control end of the switch tube Q109 is also connected to the second end of the switch tube Q109 and the second end of the capacitor EC101 through the resistor R119. Specifically, the chip select end of the controller U102 is used to collect the voltage output from the fifth pin of the transformer T100, and the chip select section of the controller U101 is used to collect the voltage from the seventh pin of the transformer T100, and then based on the collected voltage, control signals are output to the control end of the corresponding switch tube Q103 and the control end of the switch tube Q109, respectively, so as to control the voltage of the capacitor EC101 to the ground. It should be noted that the ground end of the EC101 is a digital ground, and the voltage of the digital ground is controlled by the synchronous rectification unit 332, so as to control the voltage output by the resonance module 33. Based on this, the current can be dynamically output to the LED display screen 200.

[0063] In some embodiments, the switch tubes Q3, Q4, Q5, Q103 and Q109 are all superjunction field effect tubes, wherein the superjunction field effect tubes refer to the process of semiconductor doping in which different types of impurities are alternately doped to form an interlaced PN structure. Such a structure can distribute the electric field more evenly, thereby reducing resistance and voltage loss and improving switching speed and efficiency.

[0064] Furthermore, the power processing circuit 300 further includes an output overvoltage protection module 35 (not shown), wherein Figure 4a As shown, the output overvoltage protection module 35 includes a switch tube Q107, a switch tube Q108, a resistor R112, a controller U103 and a complementary triode Q106; the complementary triode Q106 is connected to the control module 31 and the controller U103 respectively, the output end of the controller U103 is connected to the control end of the switch tube Q107 and the control end of the switch tube Q108 respectively, the first ends of the switch tube Q107 and the switch tube 108 are connected to the resonance module 33 respectively, the first ends of the switch tube Q107 and the switch tube 108 are also connected to the output end of the controller U103 through the resistor R112, the second ends of the switch tube Q107 and the switch tube 108 are also connected to the complementary triode Q106, and the second ends of the switch tube Q107 and the switch tube 108 are also used to connect to the LED display screen 200. The switch tube Q107 and the switch tube Q108 are load switches, which detect the status of the LED display screen 200 and other peripheral devices through the controller U103, and when the LED display screen 200 or other peripheral devices fail, output drive signals to the control ends of the switch tubes Q107 and Q108, thereby disconnecting the power supply processing circuit 300 and the LED display screen 200 through the switch tubes Q107 and Q108, thereby protecting the devices in the power supply processing circuit 300.

[0065] See also Figure 5 , Figure 5 is a circuit diagram of a control module provided by an embodiment of the utility model, such as Figure 5 As shown, the control module 31 is a chip U1, and the first pin of the chip U1 is used to collect the alternating current input by the power supply 100, and judge the size of the alternating current, and then output a driving signal to the controller U100 through the fifth pin of the chip U1 based on the judgment result, so as to output a preset voltage. At the same time, the sixth and tenth pins of the chip U1 respectively output control signals to the switch tube Q4 and the switch tube Q5, so as to control the soft start of the switch tube Q4 and the switch tube Q5, so as to make the transformer T100, the inductor L102 and the capacitor EC101 start to resonate, and then output the target power to the LED display screen 200.

[0066] In some embodiments, the LED system 1 further includes a current sharing control circuit (not shown), a loop control circuit (not shown) and a protection circuit (not shown), wherein the current sharing control circuit is connected to the output end of the resonance module 33, and is mainly used for each of the power processing circuits to share the current when the power processing circuit 300 includes multiple circuits working simultaneously. The loop control circuit is respectively connected to the output end of the resonance module 33 and the control module 31, and is mainly used to control the output of the resonance module 33 to achieve an output voltage in the range of 3.8V0-5V. The protection circuit is respectively connected to the control module 31 and the resonance module 33, and is mainly used for overvoltage and overtemperature protection. For example, when an overvoltage occurs on the secondary side of the transformer T100, a signal is output to the control module 31 through the protection circuit, thereby shutting down the output drive signal, and then controlling the power processing circuit 300 to stop working.

[0067] Specifically, Figure 6 As shown, Figure 6 It is a circuit diagram of a current balancing circuit provided by an embodiment of the utility model, and the current balancing circuit includes an operational amplifier U201A, an operational amplifier U201B, a resistor R239, a resistor R240, a resistor R233 and a resistor R246; the positive input terminal of the operational amplifier U201A is connected to the first end of the capacitor EC101, the reverse input terminal of the U201A is connected to the first end of the switch tube Q108 through the resistor R239, the reverse input terminal of the operational amplifier U201A is also connected to the output terminal of the operational amplifier U201A and the resistor R246 respectively through the resistor R240, the output terminal of the operational amplifier U201A is also connected to the positive input terminal of the operational amplifier U201B through the resistor R233, and the resistor R246 is also connected to the reverse input terminal of the operational amplifier U201B.

[0068] Further, such as Figure 7 As shown, Figure 7: is a circuit diagram of a loop control circuit provided by an embodiment of the utility model, the loop control circuit includes an optical coupler P201, a voltage regulator U202, a resistor R227, a resistor R235, a resistor R238, a diode D208, a resistor R228, a resistor R241, a resistor R247, a resistor R243, a capacitor C232, a switch tube Q202 and a resistor R245; the 4th foot of the optical coupler P201 is connected to the 16th foot of the chip U1, the 1st foot of the optical coupler P201 is connected to the resonance module 33, the second foot of the optical coupler P201 is connected to the voltage regulator U202, and the voltage regulator U202 is also connected to the resonance module through the resistor R227. The first end of the voltage regulator tube U202 is also connected to the resistor R238 through the resistor R235. The diode D208 is respectively connected to the resonance module 33 and the resistor R238. The resistor R238 is also respectively connected to the resonance module 33 through the resistor R232 and to the resistor R243 through the resistor R247. The resistor R243 is also used for grounding. The resistor R232 is also connected to the first end of the switch tube Q202. The control end of the switch tube Q202 is also grounded through the resistor R245. The control end of the switch tube Q202 is also connected to the output end of the operational amplifier U201B.

[0069] In some embodiments, see Figure 8 , Figure 8 is a circuit diagram of a protection circuit provided by an embodiment of the utility model, such as Figure 8 As shown, the protection circuit includes a thermistor RT201, a switch tube Q6, a diode D8, an optocoupler P200, a voltage regulator tube Z201, a voltage regulator tube D201, a voltage regulator tube U200, a resistor R202, a thermistor U200, a resistor R205 and a voltage regulator tube D203; the control end of the switch tube Q6 is grounded through the diode D8, and the control end of the switch tube Q6 is also connected to the first voltage through the thermistor RT201, the first end of the switch tube Q6 is connected to the second pin of the chip U1, and the thermistor RT2 The other end of 01 is connected to the third pin of the optocoupler P200, the first pin of the optocoupler P200 is connected to the resonance module 33 through the voltage regulator Z201, the voltage regulator Z201 is also connected to the resistor R202 and the voltage regulator U200 through the voltage regulator D201, the resistor R202 is also connected to the second voltage, the voltage regulator U200 is also grounded through the thermistor RT200, and is connected to the second voltage through the resistor R207, and the resistor R207 is also grounded through the voltage regulator D203.

[0070] The embodiment of the utility model provides a power processing circuit, including a control module, a power factor correction module and a resonance module; the control module is connected to the power factor correction module and the resonance module respectively, the power factor correction module is connected to the resonance module, the power factor correction module is also used to connect to the power supply, and the resonance module is also used to connect to the LED display. The control module is used to detect the alternating current output by the power supply, and control the power factor correction module based on the alternating current so that the power factor correction module outputs a preset voltage. Based on this, when a small voltage is input, the power factor correction module is used to boost the voltage, so that when providing the target power, only the voltage reduction operation is required, thereby avoiding the addition of redundant devices and improving the output efficiency. And output a control signal to the resonance module, so that the resonance module processes the preset voltage based on the control signal to provide the target power for the LED display. Based on this, the heat generation of the device can be reduced while reducing the loss.

[0071] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Under the idea of ​​the present invention, the technical features in the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other changes in different aspects of the present invention as described above, which are not provided in detail for the sake of simplicity. Although the present invention has been described in detail with reference to the aforementioned embodiments, a person of ordinary skill in the art should understand that the technical solutions described in the aforementioned embodiments can still be modified, or some of the technical features can be replaced by equivalents. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A power processing circuit, It is characterized in that The power processing circuit includes a control module, a power factor correction module and a resonance module; The control module is connected to the power factor correction module and the resonance module respectively, the power factor correction module is connected to the resonance module, the power factor correction module is also used to connect to a power source, and the resonance module is also used to connect to an LED display screen; The control module is used to detect the alternating current output by the power supply, and control the power factor correction module based on the alternating current, so that the power factor correction module outputs a preset voltage; as well as A control signal is output to the resonance module, so that the resonance module processes the preset voltage based on the control signal to provide target power for the LED display.

2. The power processing circuit according to claim 1, It is characterized in that The power correction factor module includes an inductor L100, a controller U100, a switch tube Q3, a resistor R108, a resistor R110 and a resistor R121; The input end of the controller U100 is connected to the control module, the high-level output end of the controller U100 is connected to the control end of the switch tube Q3 through the resistor R108, the low-level output end of the controller U100 is connected to the control end of the switch tube Q3 through the resistor R110, the control end of the switch tube Q3 is also connected to the second end of the switch tube Q3 through the resistor R121, and the first end of the switch tube Q3 is connected to the power supply and control module through the inductor L100.

3. The power processing circuit according to claim 1, It is characterized in that The resonance module includes an LLC resonance unit and a synchronous rectification unit; The control end of the LLC resonance unit is connected to the control module, the input end of the LLC resonance unit is connected to the power factor correction module, and the output end of the LLC resonance unit is connected to the LED display screen through the synchronous rectification unit; The LLC resonance unit is used to receive the preset voltage and adjust the preset voltage to output a current signal; The synchronous rectification unit is used to detect the current signal output by the LLC resonance unit, and adjust the reference voltage based on the current signal to adjust the magnitude of the current signal output by the LLC resonance unit.

4. The power processing circuit according to claim 3, It is characterized in that The LLC resonant unit includes a switch tube Q4, a switch tube Q5, a transformer T100, a diode D103, a diode D104, a resistor R124, a resistor R127, an inductor L102 and a capacitor EC101; The control end of the switch tube Q4 is connected to the control module through the resistor R124, the first end of the switch tube Q1 is connected to the power factor correction module, the second end of the switch tube Q4 is respectively connected to the second end of the transformer T100 and the first end of the switch tube Q5, the control end of the switch tube Q5 is connected to the control module through the resistor R127, the first end of the transformer T100 is used for grounding, the third end of the transformer T100 is connected to the power factor correction module through the diode D103, the fifth end and the seventh end of the transformer T100 are connected to the second end of the capacitor EC101 through the synchronous rectification unit, and the sixth end of the transformer T100 is connected to the first end of the capacitor EC101 through the inductor L102.

5. The power processing circuit according to claim 4, It is characterized in that The synchronous rectification unit includes a switch tube Q103, a switch tube Q109, a controller U101, a controller U102, a resistor R109 and a resistor R119; The first end of the switch tube Q103 is respectively connected to the chip selection end of the controller U101 and the fifth end of the transformer T100, the control end of the switch tube Q103 is connected to the driving pulse end of the controller U101, and the control end of the switch tube Q103 is also connected to the second end of the switch tube Q103 and the second end of the capacitor EC101 through the resistor R109, the first end of the switch tube Q109 is respectively connected to the chip selection end of the controller U102 and the seventh end of the transformer T100, the control end of the switch tube Q109 is connected to the driving pulse end of the controller U102, and the control end of the switch tube Q109 is also connected to the second end of the switch tube Q109 and the second end of the capacitor EC101 through the resistor R119.

6. The power processing circuit according to claim 2, It is characterized in that The switch tube Q3 , the switch tube Q4 , the switch tube Q5 , the switch tube Q103 and the switch tube Q109 are all super junction field effect tubes.

7. The power processing circuit according to claim 1, It is characterized in that The power processing circuit further includes a surge protection module, wherein the surge protection module includes a thermistor RT100, a varistor RV100, a capacitor CY100, an inductor L101, and a rectifier bridge D102; The two ends of the varistor RV100 are respectively connected to the live wire and the neutral wire of the power supply, the varistor RV100 is also connected to the ground wire of the power supply through the capacitor CY100, the thermistor RT100 is respectively connected to the neutral wire of the power supply and the first end of the inductor L101, the fourth end of the inductor L101 is connected to the live wire of the power supply, the second end and the third end of the inductor L101 are respectively connected to the rectifier bridge D102, and the rectifier bridge D102 is also connected to the power factor correction module.

8. The power processing circuit according to claim 1, It is characterized in that The power processing circuit further includes an overcurrent protection module, which includes a resistor R125, a resistor RS100 and a capacitor C104; The resistor RS100 is connected to the power supply and the ground terminal respectively, the resistor R125 is connected in series with the capacitor C104, and the resistor R125 and the capacitor C104 are also connected in parallel with the resistor RS100.

9. The power processing circuit according to claim 1, It is characterized in that The power processing circuit further includes an output overvoltage protection module, which includes a switch tube Q107, a switch tube Q108, a resistor R112, a controller U103 and a complementary triode Q106; The complementary triode Q106 is connected to the control module and the controller U103 respectively, the output end of the controller U103 is connected to the control end of the switch tube Q107 and the control end of the switch tube Q108 respectively, the first ends of the switch tube Q107 and the switch tube 108 are connected to the resonance module respectively, the first ends of the switch tube Q107 and the switch tube 108 are also connected to the output end of the controller U103 through the resistor R112, the second ends of the switch tube Q107 and the switch tube 108 are also connected to the complementary triode Q106, and the second ends of the switch tube Q107 and the switch tube 108 are also used to connect to the LED display screen.

10. An LED system, It is characterized in that The LED system comprises: power supply; LED display screen; and A power processing circuit as claimed in any one of claims 1 to 9.

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