Digitally controlled power supply constant current system and electronic equipment

Abstract

An embodiment of the present invention provides a digitally controlled power supply constant current system and electronic equipment. The power supply constant current system includes an LLC input circuit, an LLC resonant network circuit, and an LED power distribution network circuit electrically connected in sequence, and also includes an isolated input sampling circuit, a single-chip microcomputer controller, and an output sampling circuit. The isolated input sampling circuit is electrically connected to the LLC input circuit, the single-chip microcomputer controller is electrically connected to the LLC resonant network circuit, and the output sampling circuit is electrically connected to the LED power distribution network circuit. The present invention can achieve constant current output under the conditions of input undervoltage protection and output overvoltage protection by relying solely on the single-chip microcomputer controller, without the need to configure an undervoltage protection circuit and an overvoltage protection circuit, thereby reducing the use of electronic components, reducing the size of the PCB version, and thus reducing the cost of use.

Description

Technical Field

[0001] The embodiments of the present invention relate to the technical field of power supply constant current systems, and in particular to a digitally controlled power supply constant current system and electronic equipment. Background Art

[0002] Existing power supply constant current systems utilize LLC (Logical Link Control) direct drive coupled with a power distribution network to achieve multi-channel constant current control. This enables high-power constant current backlight drive, resulting in a high-efficiency drive solution. However, this power supply constant current system requires undervoltage and overvoltage protection circuits to achieve constant current control in both undervoltage and overvoltage conditions. Existing power supply constant current systems are constructed entirely of electronic components, resulting in a complex system architecture, a large PCB (Printed Circuit Board), and the use of numerous electronic components, resulting in high costs. Summary of the Invention

[0003] In view of this, an embodiment of the present invention provides a digitally controlled power supply constant current system and electronic equipment, which can reduce the use of electronic components and effectively reduce the use cost.

[0004] In a first aspect, an embodiment of the present invention provides a digitally controlled power supply constant current system, the power supply constant current system comprising an LLC input circuit, an LLC resonant network circuit, and an LED power distribution network circuit electrically connected in sequence, wherein the power supply constant current system further comprises: an isolated input sampling circuit, a single-chip microcomputer controller, and an output sampling circuit, wherein the isolated input sampling circuit is electrically connected to the LLC input circuit, the single-chip microcomputer controller is electrically connected to the LLC resonant network circuit, and the output sampling circuit is electrically connected to the LED power distribution network circuit;

[0005] The isolated input sampling circuit is used to collect the input voltage of the LLC input circuit and transmit the input voltage to the single chip controller;

[0006] The single-chip microcomputer controller is used to determine whether the input voltage is undervoltage. If the input voltage is not undervoltage, it outputs a pulse wave to the LLC resonant network circuit to control the opening and closing of the switching components in the LLC resonant network circuit to light up the LED lights in the LED power distribution network circuit;

[0007] The output sampling circuit is used to collect the output voltage and output current of the LED power distribution network circuit when the LED lamp is lit, and transmit the output voltage and output current to the single chip controller;

[0008] The single-chip microcomputer controller is also used to determine whether the output voltage is overvoltage. If the output voltage is not overvoltage, it detects whether the output current reaches the preset constant current value. When the output current does not reach the preset constant current value, the output frequency of the pulse wave is adjusted based on the output current and the preset constant current value until the output current reaches the preset constant current value.

[0009] In one possible implementation, the isolated input sampling circuit includes an isolation amplifier and an input sampling circuit electrically connected; the isolation amplifier is electrically connected to the LLC input circuit, and the input sampling circuit is electrically connected to the single-chip microcomputer controller;

[0010] The isolation amplifier is used to step down the input voltage of the LLC input circuit and transmit the stepped-down output voltage to the microcontroller controller through the input sampling circuit.

[0011] In one possible implementation, the power constant current system further includes an isolation driver chip, and the LLC resonant network circuit and the single-chip microcomputer controller are both electrically connected to the isolation driver chip;

[0012] The isolation driver chip is used to receive the pulse wave output by the single-chip microcomputer controller, boost the pulse wave, and transmit the boosted pulse wave to the LLC resonant network circuit.

[0013] In one possible implementation, adjusting the output frequency of the pulse wave based on the output current and a preset constant current value includes:

[0014] Obtaining the PID control parameters, the first output current, and the second output current of the single-chip microcomputer controller; wherein the first output current is the output current at the previous moment, and the second output current is the output current at the moment before the output current;

[0015] Calculating a current regulation amount based on the output current, a preset constant current value, a PID control parameter, the first output current, and the second output current;

[0016] Calculate the output frequency of the pulse wave according to the current regulation amount;

[0017] The current output frequency of the pulse wave corresponding to the output current is adjusted to the output frequency.

[0018] In one possible implementation, the current regulation amount is calculated using the following formula:

[0019] ΔI=K p ×ΔI t +K i ×ΔI t-1 +K d ×ΔI t-2 ;

[0020] Among them, ΔI represents the current regulation amount; ΔIt Indicates the difference between the preset constant current value and the output current; ΔI t-1 Indicates the difference between the preset constant current value and the first output current; ΔI t-2 Indicates the difference between the preset constant current value and the second output current; K p , K i , K d Indicates PID control parameters;

[0021] The output frequency is calculated by the following formula:

[0022] f=f t +A×ΔI t ;

[0023] Where, f represents the output frequency; f t Indicates the output frequency at the current moment; A indicates the conversion coefficient between frequency and current; ΔI t Indicates the current regulation amount.

[0024] In one possible implementation, the single chip microcomputer controller is further configured to reset when detecting input voltage undervoltage, output voltage overvoltage, or output current exceeding a preset constant current value.

[0025] In one possible implementation, the single chip microcomputer controller is further configured to perform an overvoltage protection count when the output voltage is greater than or equal to a threshold voltage, and stop outputting pulse waves to the LLC resonant network circuit when it is detected that the overvoltage protection count exceeds a preset value.

[0026] In one possible embodiment, the power constant current system further includes a system chip electrically connected to the single chip controller;

[0027] The single-chip microcomputer controller is also used to receive the dimming signal sent by the system chip, obtain the dimming duty cycle in the dimming signal, use analog dimming when the dimming duty cycle is greater than the dimming switching duty cycle, and use pulse dimming when the dimming duty cycle is equal to or less than the dimming switching duty cycle.

[0028] In one possible embodiment, the power constant current system further includes an auxiliary power supply circuit electrically connected to both the single chip controller and the LLC input circuit;

[0029] The auxiliary power supply circuit is used to provide power to the microcontroller controller.

[0030] In a second aspect, an embodiment of the present invention provides an electronic device, wherein the electronic device is configured with the above-mentioned digitally controlled power supply constant current system.

[0031] The embodiments of the present invention provide a digitally controlled power supply constant current system and electronic equipment, wherein the power supply constant current system includes an LLC input circuit, an LLC resonant network circuit, and an LED power distribution network circuit electrically connected in sequence, and further includes an isolated input sampling circuit, a single-chip microcomputer controller, and an output sampling circuit. The isolated input sampling circuit is electrically connected to the LLC input circuit, the single-chip microcomputer controller is electrically connected to the LLC resonant network circuit, and the output sampling circuit is electrically connected to the LED power distribution network circuit; the isolated input sampling circuit is used to collect the input voltage of the LLC input circuit and transmit the input voltage to the single-chip microcomputer controller; the single-chip microcomputer controller is used to determine whether the input voltage is undervoltage, and when it is determined that the input voltage is not undervoltage, the single-chip microcomputer controller is used to determine whether the input voltage is undervoltage. When the output voltage is overvoltage, the output current is detected to determine whether the output voltage is overvoltage. If the output voltage is not overvoltage, the output current is detected to determine whether the output current reaches a preset constant current value. If the output current does not reach the preset constant current value, the output frequency of the pulse wave is adjusted based on the output current and the preset constant current value until the output current reaches the preset constant current value. The present invention can achieve constant current output under the conditions of input undervoltage protection and output overvoltage protection by relying solely on the single-chip microcomputer controller, without the need to configure an undervoltage protection circuit and an overvoltage protection circuit, thereby reducing the use of electronic components and the size of the PCB layout, thereby reducing the cost of use. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 A schematic structural diagram of a digitally controlled power supply constant current system provided by an embodiment of the present invention;

[0033] Figure 2 A flow chart of an embodiment of a method for controlling output constant current provided by an embodiment of the present invention;

[0034] Figure 3 A schematic diagram of a single-chip microcomputer controller port connection provided by an embodiment of the present invention;

[0035] Figure 4 A schematic diagram of a pulse wave output phase shift provided by an embodiment of the present invention;

[0036] Figure 5 A schematic diagram of a complementary dimming method provided by an embodiment of the present invention;

[0037] Figure 6 A schematic structural diagram of an electronic device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0038] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts shall fall within the scope of protection of the present invention.

[0039] To facilitate understanding of the embodiments of the present invention, specific embodiments will be further explained below with reference to the accompanying drawings. The embodiments do not limit the embodiments of the present invention.

[0040] The embodiment of the present invention provides a digitally controlled power constant current system, such as Figure 1 As shown, the power constant current system includes an LLC (Logical Link Control) input circuit 107, an LLC resonant network circuit 108 and an LED (Light Emitting Diode) power distribution network circuit 109 electrically connected in sequence. Typically, the LLC input circuit is composed of a current source, an EMI (Electro Magnetic Interference) circuit, a rectifier filter circuit and a PFC (Power Factor Corrector) circuit connected in sequence, and is used to provide input voltage for lighting the LED lamp.

[0041] The specific circuit structure of the LLC resonant network circuit can be found in Figure 1 The LLC resonant network circuit includes resistors, switch components, namely MOS (Metal Oxide Semiconductor) tubes, transformers and capacitors. The specific circuit structure of the LED power distribution network circuit 109 can also be found in Figure 1 , LED power distribution network circuit includes LED lamp group, resistor and diode, Figure 1 Only two LED light groups are shown as an example. The number of specific LED light groups is related to the output channels specifically included in the following single-chip microcomputer controller. If the single-chip microcomputer controller includes 4 output channels, the number of LED light groups can be 4 groups. If the single-chip microcomputer controller includes 6 or 8 output channels, the number of LED light groups can be 6 or 8 groups. The number of LED light groups is not limited here.

[0042] like Figure 1As shown, the above-mentioned power constant current system also includes: an isolated input sampling circuit 100, a single-chip microcomputer controller 101 and an output sampling circuit 102. The isolated input sampling circuit 100 is electrically connected to the LLC input circuit 107, the single-chip microcomputer controller 101 is electrically connected to the LLC resonant network circuit 108, and the output sampling circuit 102 is electrically connected to the LED power distribution network circuit 109.

[0043] Specifically, the isolated input sampling circuit is used to collect the input voltage of the LLC input circuit and transmit the input voltage to the single-chip microcomputer controller; the single-chip microcomputer controller is used to determine whether the input voltage is undervoltage, and when it is determined that the input voltage is not undervoltage, output a pulse wave to the LLC resonant network circuit to control the opening and closing of the switching components in the LLC resonant network circuit to light up the LED lamp in the LED power distribution network circuit; the output sampling circuit is used to collect the output voltage and output current of the LED power distribution network circuit when the LED lamp is lit, and transmit the output voltage and output current to the single-chip microcomputer controller; the single-chip microcomputer controller is also used to determine whether the output voltage is overvoltage, and when it is determined that the output voltage is not overvoltage, detect whether the output current reaches a preset constant current value, and when the output current does not reach the preset constant current value, adjust the output frequency of the pulse wave based on the output current and the preset constant current value until the output current reaches the preset constant current value.

[0044] Usually, before using the single-chip microcomputer controller to achieve constant current output, it is necessary to initialize the single-chip microcomputer controller first, and then realize the output constant current based on the input voltage, output voltage and output current. In order to understand the control process of the single-chip microcomputer controller, Figure 2 A flow chart of an embodiment of a method for controlling output constant current is shown, which is applicable to the above-mentioned single chip controller, such as Figure 2 As shown, the method may include the following steps:

[0045] Step 200, start;

[0046] Step 201, initializing the single chip microcomputer controller;

[0047] Step 202: receiving an isolated input sampling circuit to collect an input voltage inputted by the LLC input circuit;

[0048] Step 203, determining whether the input voltage is undervoltage;

[0049] If the input voltage is undervoltage, step 202 is executed; if the input voltage is not undervoltage, step 204 is executed.

[0050] Step 204: outputting a pulse wave to the LLC resonant network circuit to control the opening and closing of the switching components in the LLC resonant network circuit to light up the LED lamps in the LED power distribution network circuit;

[0051] In this embodiment, the pulse wave is a PWM (Pulse Width Modulation) wave.

[0052] Step 205 , the receiving output sampling circuit collects the output voltage and output current of the LED power distribution network circuit when the LED lamp is lit;

[0053] Step 206, determining whether the output voltage is overvoltage;

[0054] If the output voltage is overvoltage, step 207 is executed; if the output voltage is not undervoltage, step 208 is executed.

[0055] Step 207, stop the pulse wave output and reset the single chip controller;

[0056] Overvoltage may damage the LED lamp. In order to protect the LED lamp, the pulse wave output needs to be stopped. After executing step 207, it is necessary to return to execute step 202.

[0057] Step 208, detecting whether the output current reaches a preset constant current value;

[0058] The preset constant current value can be set according to actual needs and is not limited here. If the output current reaches the preset constant current value, step 210 is executed to end the above process; if the output current does not reach the preset constant current value, step 209 is executed.

[0059] Step 209, adjusting the output frequency of the pulse wave based on the output current and the preset constant current value;

[0060] The above output frequency is used to control the number of PWM cycles per second. The higher the output frequency, the more PWM cycles there are, and the lower the output frequency, the fewer PWM cycles there are. A PWM cycle refers to a period in which the signal goes from a high level to a low level and then back to a high level.

[0061] In a specific implementation, different PWM cycles per second (PWM) result in different on-off frequencies of the switching components in the LLC resonant network circuit, leading to different resonant frequencies of the LLC resonant network circuit. This in turn causes the LLC resonant network circuit to affect the output current of the LED power distribution network circuit. Therefore, the output current can be adjusted by adjusting the output frequency. Since the process by which the LLC resonant network circuit affects the output current of the LED power distribution network circuit is known in the art, it will not be described in detail here.

[0062] The specific process of adjusting the output frequency of the pulse wave can be achieved by steps A1 to A4:

[0063] Step A1, obtaining a PID (Proportion Integration Differentiation) control parameter, a first output current, and a second output current of a single-chip microcomputer controller; wherein the first output current is the output current at the previous moment, and the second output current is the output current at the moment before that;

[0064] Step A2, calculating a current adjustment amount based on the output current, a preset constant current value, a PID control parameter, the first output current, and the second output current;

[0065] The current regulation is calculated by the following formula:

[0066] ΔI=K p ×ΔI t +K i ×ΔI t-1 +K d ×ΔI t-2 ;

[0067] Among them, ΔI represents the current regulation amount; ΔI t Indicates the difference between the preset constant current value and the output current; ΔI t-1 Indicates the difference between the preset constant current value and the first output current; ΔI t-2 Indicates the difference between the preset constant current value and the second output current; K p , K i , K d Indicates PID control parameters.

[0068] Step A3, calculating the output frequency of the pulse wave according to the current adjustment amount;

[0069] The output frequency is calculated by the following formula:

[0070] f=f t +A×ΔI t ;

[0071] Where, f represents the output frequency; f t Indicates the output frequency at the current moment; A indicates the conversion coefficient between frequency and current; ΔI t Indicates the current regulation amount.

[0072] In this embodiment, the process returns to step 202 according to the adjusted output frequency, and the output frequency is adjusted until the output current reaches a preset constant current value.

[0073] Step A4: adjusting the current output frequency of the pulse wave corresponding to the output current to the output frequency.

[0074] Step 210, end.

[0075] The digitally controlled power supply constant current system provided in an embodiment of the present invention can achieve output constant current under the conditions of input undervoltage protection and output overvoltage protection by relying solely on a single-chip microcomputer controller. There is no need to configure an undervoltage protection circuit and an overvoltage protection circuit, which reduces the use of electronic components and the size of the PCB (Printed Circuit Board), thereby reducing the cost of use.

[0076] like Figure 1 As shown, the above-mentioned isolated input sampling circuit 100 includes an electrically connected isolation amplifier 103 and an input sampling circuit 104; the isolation amplifier 103 is electrically connected to the LLC input circuit 107, and the input sampling circuit 104 is electrically connected to the microcontroller controller 101; the isolation amplifier 103 is used to step down the input voltage input by the LLC input circuit and transmit the stepped-down output voltage to the microcontroller controller through the input sampling circuit.

[0077] Usually the input voltage of the LLC input circuit is 220V, while the voltage used by the microcontroller controller is dozens of volts, so the input voltage of the LLC input circuit needs to be stepped down.

[0078] like Figure 1 As shown, the power constant current system also includes an isolation driver chip 105, and the LLC resonant network circuit 108 and the single-chip microcomputer controller 101 are electrically connected to the isolation driver chip; the isolation driver chip is used to receive the pulse wave output by the single-chip microcomputer controller, boost the pulse wave, and transmit the boosted pulse wave to the LLC resonant network circuit.

[0079] The voltage required to control the on / off of the switch components in the LLC resonant network circuit is higher than the voltage required by the single chip controller 101 , so the pulse wave needs to be boosted.

[0080] In actual use, the single-chip microcomputer controller can be electrically connected to the above-mentioned input sampling circuit and output sampling circuit through its own ADC (Analog to digital converter) port, and electrically connected to the isolation driver chip through its own timer port. Through the ADC port of the single-chip microcomputer controller, the input and output of the entire power supply constant current system can be sampled, and the collected voltage can be fed back to the single-chip microcomputer controller, so that the entire power supply constant current system maintains a stable constant current output.

[0081] For ease of understanding, Figure 3As shown, taking the single-chip microcomputer controller with four timer ports as an example, the single-chip microcomputer controller can control four groups of LED lights to light up. The existing power supply constant current system output can only carry 2 outputs at most, so this solution cannot meet the needs of systems with more than 2 outputs (such as 4CH / 8CH / 16CH multi-channel output). In addition, in the existing power supply constant current system, multiple outputs are opened and closed at the same time, resulting in noise problems caused by large current fluctuations. This embodiment uses a single-chip microcomputer controller as the control chip, and uses the pulse wave output by its own timer to replace the drive signal. In principle, as long as there are enough timer ports, the single-chip microcomputer controller can carry multiple outputs such as 4CH / 8CH / 16CH. The output can be delayed for a certain time interval before opening to achieve phase shifting between outputs ( Figure 4 , Figure 4 Among them, CH1, CH2, CH3, and CH4 are four pulse waves output by the MCU controller with delay to solve the noise problem.

[0082] In this embodiment, the single chip microcomputer controller is further configured to reset when an input voltage undervoltage, an output voltage overvoltage, or an output current exceeding a preset constant current value is detected.

[0083] In actual use, existing power supply constant current systems use analog chips as constant current output control. However, when an abnormality occurs in the existing power supply constant current system (such as overvoltage, overcurrent, undervoltage, etc.), the analog chip itself cannot be reset, resulting in the entire existing power supply constant current system being unable to reset. However, this embodiment uses a single-chip microcomputer controller as the control chip of the power supply constant current system. Through software programming, when an abnormality occurs in the power supply constant current system, an abnormality signal is transmitted to the single-chip microcomputer controller through an event trigger / interrupt trigger. After receiving the abnormality signal, the single-chip microcomputer controller spontaneously completes the reset of the single-chip microcomputer controller, thereby completing the reset of the entire power supply constant current system.

[0084] To protect the LED lamp from damage due to overvoltage, in this embodiment, the single-chip microcomputer controller is further configured to perform an overvoltage protection count when the output voltage is greater than or equal to a threshold voltage. If the overvoltage protection count exceeds a preset value, the controller stops outputting pulse waves to the LLC resonant network circuit. This preset value can be set according to actual needs and is not limited here. A preferred preset value is 3.

[0085] The existing power supply constant current system requires an external overvoltage protection circuit to protect the LED lamp. By using only a single-chip microcomputer controller, the protection of the LED lamp can be achieved. Compared with the existing power supply constant current system, this overvoltage protection method not only saves the components of the protection circuit and reduces the circuit cost, but also the overvoltage point and overvoltage processing can be flexibly controlled through programming.

[0086] The existing power constant current system has a single dimming method, either pure pulse dimming or pure analog dimming. When using pure pulse dimming and the brightness is high, in order to obtain the same average current, the required voltage is higher than that of analog dimming, resulting in relatively high energy consumption. When using analog dimming, due to the limitation of analog dimming transmission ratio, when the duty cycle of the dimming signal BL_ADJ is 0, the average current is not equal to 0, resulting in the brightness not being able to dim down (such as Figure 5 ).

[0087] In order to solve the above problems, this embodiment can realize the complementary dimming use of pulse dimming and analog dimming on the basis of realizing single pulse dimming and single analog dimming. In the specific implementation, the power supply constant current system also includes a system chip electrically connected to the single-chip microcomputer controller; the single-chip microcomputer controller is also used to receive the dimming signal sent by the system chip, obtain the dimming duty cycle in the dimming signal, and adopt analog dimming when the dimming duty cycle is greater than the dimming switching duty cycle, and adopt pulse dimming when the dimming duty cycle is equal to or less than the dimming switching duty cycle.

[0088] The above-mentioned dimming switching duty cycle can be adjusted according to actual usage requirements. This embodiment can use pulse dimming when the duty cycle is small, and automatically switch to analog dimming when the duty cycle is large, so that at a low duty cycle, a low brightness state can be achieved. At a high duty cycle, it can reduce both the dimming noise and the overall power consumption, thereby improving the energy efficiency of the entire machine.

[0089] From the above content, it can be seen that this embodiment adopts a single-chip microcomputer controller as the control chip of the entire power supply constant current system, and realizes automatic reset, LED lamp overvoltage protection, mixed dimming, input and output sampling, multi-channel output and channel phase mismatch functions through software programming. Compared with the existing power supply constant current system using analog chips, solidified control, fixed functions and unchangeable shortcomings, the single-chip microcomputer controller of this embodiment can be programmed according to needs, and has flexible and diverse functions.

[0090] In actual use, in order to ensure the normal operation of the single-chip microcomputer controller, it is necessary to provide power to the single-chip microcomputer controller, such as Figure 1 As shown, the power constant current system further includes an auxiliary power supply circuit 106 electrically connected to the single chip controller 100 and the LLC input circuit 107; Figure 1 As shown, the auxiliary power supply circuit includes an auxiliary circuit, an output rectifier and filter circuit, a PWM power supply control chip, and a feedback circuit to provide power to the single-chip microcomputer controller.

[0091] An embodiment of the present invention provides an electronic device, wherein the electronic device is configured with the above-mentioned digitally controlled power constant current system. The electronic device can be a device that requires a screen to be lit, such as a television, a mobile phone, or a computer, and is not limited here.

[0092] Figure 6 A schematic diagram of the structure of an electronic device provided by an embodiment of the present invention is provided. Figure 6 The electronic device 500 shown includes: at least one processor 501, a memory 502, at least one network interface 504 and another user interface 503. The various components in the electronic device 500 are coupled together via a bus system 505. It is understood that the bus system 505 is used to achieve connection and communication between these components. In addition to including a data bus, the bus system 505 also includes a power bus, a control bus and a status signal bus. However, for the sake of clarity, the bus system 505 is not shown in FIG. Figure 6 Various buses are labeled as bus system 505.

[0093] The user interface 503 may include a display, a keyboard, or a pointing device (eg, a mouse, a trackball, a touchpad, or a touch screen).

[0094] It is understood that the memory 502 in the embodiment of the present invention can be a volatile memory or a non-volatile memory, or can include both volatile and non-volatile memories. Among them, the non-volatile memory can be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory can be a random access memory (RAM), which is used as an external cache. By way of example and not limitation, many forms of RAM are available, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDRSDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link DRAM (SLDRAM), and direct RAM bus random access memory (DRRAM). The memory 502 described herein is intended to include, but is not limited to, these and any other suitable types of memory.

[0095] In some embodiments, the memory 502 stores the following elements, executable units, or data structures, or a subset thereof, or an extended set thereof: an operating system 5021 and application programs 5022 .

[0096] The operating system 5021 includes various system programs, such as a framework layer, a core library layer, and a driver layer, for implementing various basic services and handling hardware-based tasks. Application programs 5022 include various application programs, such as a media player and a browser, for implementing various application services. Programs implementing the methods of the embodiments of the present invention may be included in application programs 5022.

[0097] In the embodiment of the present invention, the processor 501 is configured to execute the method steps provided in each method embodiment by calling a program or instruction stored in the memory 502 , specifically, a program or instruction stored in the application 5022 .

[0098] The methods disclosed in the above embodiments of the present invention can be applied to or implemented by processor 501. Processor 501 may be an integrated circuit chip with signal processing capabilities. During implementation, each step of the above method can be completed by hardware integrated logic circuits in processor 501 or by software instructions. The above processor 501 may be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. The methods, steps, and logic block diagrams disclosed in the embodiments of the present invention can be implemented or executed. The general-purpose processor may be a microprocessor or any conventional processor. The steps of the methods disclosed in conjunction with the embodiments of the present invention can be directly implemented and executed by a hardware decoding processor, or by a combination of hardware and software units in the decoding processor. The software units can be located in storage media well-known in the art, such as random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, etc. The storage medium is located in the memory 502 , and the processor 501 reads the information in the memory 502 and completes the steps of the above method in combination with its hardware.

[0099] It is understood that the embodiments described herein may be implemented using hardware, software, firmware, middleware, microcode, or a combination thereof. For hardware implementation, the processing unit may be implemented in one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field-programmable gate arrays (FPGAs), general-purpose processors, controllers, microcontrollers, microprocessors, other electronic units for performing the functions described herein, or a combination thereof.

[0100] For software implementation, the technology described herein can be implemented by a unit that performs the functions described herein. The software code can be stored in a memory and executed by a processor. The memory can be implemented in the processor or outside the processor.

[0101] The electronic device provided in this embodiment may be Figure 6 The electronic device shown in FIG. 1 can perform the following operations: Figure 2 All the steps in the Figure 2 For details on the technical effects of the method shown, please refer to Figure 2 For the sake of brevity, the relevant description will not be repeated here.

[0102] An embodiment of the present invention further provides a storage medium (computer-readable storage medium). The storage medium stores one or more programs. The storage medium may include volatile memory, such as random access memory; the memory may also include non-volatile memory, such as read-only memory, flash memory, hard disk, or solid-state drive; and the memory may also include a combination of the aforementioned types of memory.

[0103] When one or more programs in the storage medium can be executed by one or more processors, the above method for controlling output constant current is realized.

[0104] The processor is used to execute the output constant current control program stored in the memory to implement the steps of the output constant current control method.

[0105] Professionals should also be further aware that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the above description has generally described the components and steps of each example according to their functions. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0106] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein may be implemented using hardware, a software module executed by a processor, or a combination of the two. The software module may be placed in a random access memory (RAM), a memory, a read-only memory (ROM), an electrically programmable ROM, an electrically erasable programmable ROM, a register, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.

[0107] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A digitally controlled power constant current system, comprising an LLC input circuit, an LLC resonant network circuit, and an LED power distribution network circuit electrically connected in sequence, characterized in that: The power constant current system further includes: an isolated input sampling circuit, a single-chip microcomputer controller, and an output sampling circuit, wherein the isolated input sampling circuit is electrically connected to the LLC input circuit, the single-chip microcomputer controller is electrically connected to the LLC resonant network circuit, and the output sampling circuit is electrically connected to the LED power distribution network circuit; The isolated input sampling circuit is used to collect the input voltage input by the LLC input circuit and transmit the input voltage to the single chip controller; The single-chip microcomputer controller is used to determine whether the input voltage is undervoltage. If it is determined that the input voltage is not undervoltage, it outputs a pulse wave to the LLC resonant network circuit to control the opening and closing of the switching components in the LLC resonant network circuit to light up the LED lamp in the LED power distribution network circuit; The output sampling circuit is used to collect the output voltage and output current of the LED power distribution network circuit when the LED lamp is lit, and transmit the output voltage and output current to the single chip controller; The single chip microcomputer controller is also used to determine whether the output voltage is overvoltage. When it is determined that the output voltage is not overvoltage, it detects whether the output current reaches a preset constant current value. When the output current does not reach the preset constant current value, the output frequency of the pulse wave is adjusted based on the output current and the preset constant current value until the output current reaches the preset constant current value.

2. The power constant current system according to claim 1, characterized in that: The isolated input sampling circuit includes an isolation amplifier and an input sampling circuit that are electrically connected; the isolation amplifier is electrically connected to the LLC input circuit, and the input sampling circuit is electrically connected to the single-chip microcomputer controller; The isolation amplifier is used to step down the input voltage input by the LLC input circuit, and transmit the stepped-down output voltage to the single-chip microcomputer controller through the input sampling circuit.

3. The power constant current system according to claim 1, characterized in that: The power constant current system further includes an isolation driver chip, and the LLC resonant network circuit and the single chip controller are both electrically connected to the isolation driver chip; The isolation driver chip is used to receive the pulse wave output by the single-chip microcomputer controller, boost the pulse wave, and transmit the boosted pulse wave to the LLC resonant network circuit.

4. The power constant current system according to claim 1, characterized in that: The adjusting the output frequency of the pulse wave based on the output current and the preset constant current value includes: Obtaining a PID control parameter, a first output current, and a second output current of the single-chip microcomputer controller; wherein the first output current is the output current at the previous moment of the output current, and the second output current is the output current at the previous moment of the output current; Calculating a current regulation amount based on the output current, the preset constant current value, the PID control parameter, the first output current, and the second output current; Calculating the output frequency of the pulse wave according to the current adjustment amount; The current output frequency of the pulse wave corresponding to the output current is adjusted to the output frequency.

5. The power constant current system according to claim 4, characterized in that: The current regulation is calculated by the following formula: ΔI=K p ×ΔI t +K i ×ΔI t-1 +K d ×ΔI t-2 ; Wherein, ΔI represents the current adjustment amount; ΔI t Indicates the difference between the preset constant current value and the output current; ΔI t-1 represents the difference between the preset constant current value and the first output current; ΔI t-2 represents the difference between the preset constant current value and the second output current; K p , K i , K d represents the PID control parameter; The output frequency is calculated by the following formula: f=f t +A×ΔI t ; Wherein, f represents the output frequency; f t Indicates the output frequency at the current moment; A indicates the conversion coefficient between frequency and current; ΔI t Indicates the current adjustment amount.

6. The power constant current system according to claim 1, characterized in that: The single chip controller is further configured to reset when it detects that the input voltage is undervoltage, the output voltage is overvoltage, or the output current exceeds the preset constant current value.

7. The power constant current system according to claim 1, characterized in that: The single chip microcomputer controller is also used to perform overvoltage protection counting when the output voltage is greater than or equal to a threshold voltage, and stop outputting pulse waves to the LLC resonant network circuit when it is detected that the overvoltage protection count exceeds a preset value.

8. The power constant current system according to claim 1, characterized in that: The power constant current system further comprises a system chip electrically connected to the single chip controller; The single-chip microcomputer controller is also used to receive the dimming signal sent by the system chip, obtain the dimming duty cycle in the dimming signal, adopt analog dimming when the dimming duty cycle is greater than the dimming switching duty cycle, and adopt pulse dimming when the dimming duty cycle is equal to or less than the dimming switching duty cycle.

9. The power constant current system according to claim 1, characterized in that: The power constant current system further includes an auxiliary power supply circuit electrically connected to both the single chip controller and the LLC input circuit; The auxiliary power supply circuit is used to provide electrical energy to the single chip controller.

10. An electronic device, characterized in that: The electronic device is provided with the digitally controlled power supply constant current system according to any one of claims 1 to 9.

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