Current sampling circuit and method, electronic equipment and computer readable storage medium

Abstract

The embodiment of the invention discloses a current sampling circuit and method, electronic equipment and a computer readable storage medium, and belongs to the technical field of power electronics. The current sampling circuit is used for sampling output current of the power converter and comprises a conversion module used for generating sampling voltage according to the output current; the input end of the high-frequency filtering sampling module is electrically connected with the output end of the conversion module, and the high-frequency filtering sampling module is used for filtering and sampling the sampling voltage based on a first filtering constant to obtain a high-frequency sampling value; the input end of the low-frequency filtering sampling module is electrically connected with the output end of the conversion module, the low-frequency filtering sampling module is used for filtering and sampling the sampling voltage based on a second filtering constant to obtain a low-frequency sampling value, and the second filtering constant is larger than the first filtering constant; and the operation module is electrically connected with the output end of the high-frequency filtering sampling module and the output end of the low-frequency filtering sampling module, and is used for determining a current sampling correction value according to the high-frequency sampling value and the low-frequency sampling value. According to the embodiment of the invention, current sampling accuracy and high bandwidth are considered.

Description

Technical Field

[0001] This application relates to the field of power electronics technology, and in particular to current sampling circuits, methods, electronic devices, and computer-readable storage media. Background Technology

[0002] Currently, the output current ripple of switching power supplies in related technologies is large, so a filter capacitor needs to be connected to the output terminal. When the current sampling unit is designed before the output filter capacitor, if the output current sampling filter bandwidth is high, the average value of the sampled output will deviate from the average value of the actual output current; if the output current sampling filter bandwidth is low, it will not be able to respond to current overshoot caused by input voltage jumps. Summary of the Invention

[0003] The main objective of this application is to provide a current sampling circuit, method, electronic device, and computer-readable storage medium, aiming to solve the technical problems of inaccurate or slow-responding current sampling schemes in related technologies.

[0004] To achieve the above objectives, this application provides a current sampling circuit for sampling the output current of a power converter, comprising: A conversion module, wherein the input terminal of the conversion module is connected to the output current, and the conversion module is used to generate a sampling voltage based on the output current; A high-frequency filtering sampling module, wherein the input terminal of the high-frequency filtering sampling module is electrically connected to the output terminal of the conversion module, and the high-frequency filtering sampling module is used to filter and sample the sampling voltage based on a first filtering constant to obtain a high-frequency sampling value; A low-frequency filtering sampling module, wherein the input terminal of the low-frequency filtering sampling module is electrically connected to the output terminal of the conversion module, and the low-frequency filtering sampling module is used to filter and sample the sampling voltage based on a second filtering constant to obtain a low-frequency sampling value, wherein the second filtering constant is greater than the first filtering constant; The arithmetic module is electrically connected to the output terminals of the high-frequency filtering sampling module and the low-frequency filtering sampling module, respectively. The arithmetic module is used to determine the current sampling correction value based on the high-frequency sampling value and the low-frequency sampling value.

[0005] In one embodiment, the conversion module includes: A first resistor, with its first end connected to the output current; A first capacitor, with its first terminal connected to the output current and its second terminal electrically connected to the second terminal of the first resistor; An operational amplifier, wherein the first input terminal of the operational amplifier is electrically connected to the second terminal of the first resistor and the second terminal of the first capacitor, the second input terminal of the operational amplifier is electrically connected to the first terminal of the first resistor, and the output terminal of the operational amplifier is electrically connected to the input terminal of the high-frequency filtering sampling module and the input terminal of the low-frequency filtering sampling module, respectively.

[0006] In one embodiment, the high-frequency filtering sampling module includes: The second resistor has its first end electrically connected to the first output terminal of the conversion module. The second capacitor has its first terminal electrically connected to the second terminal of the second resistor, and its second terminal electrically connected to the second output terminal of the conversion module. A first analog-to-digital converter (ADC) is provided, wherein a first input terminal of the first ADC is electrically connected to a first terminal of the second capacitor, and a second input terminal of the first ADC is electrically connected to a second terminal of the second capacitor.

[0007] In one embodiment, the low-frequency filtering sampling module includes: The third resistor, the first end of which is electrically connected to the first output terminal of the conversion module; The third capacitor has its first terminal electrically connected to the second terminal of the third resistor, and its second terminal electrically connected to the second output terminal of the conversion module. A second analog-to-digital converter (ADC) is connected to a first terminal of a third capacitor, and a second terminal of the second ADC is connected to a second terminal of the third capacitor.

[0008] In one embodiment, the computing module includes: A filtering unit, the input of which is electrically connected to the output of the high-frequency filtering sampling module, is used to filter the high-frequency sampled values ​​to obtain the high-frequency sampled average value; The division unit has its input terminals electrically connected to the output terminals of the filtering unit and the low-frequency filtering sampling module, respectively. The division unit is used to determine the average value ratio based on the high-frequency sampling average value and the low-frequency sampling value. The multiplication unit has its input terminals electrically connected to the output terminals of the high-frequency filtering sampling module and the division unit, respectively. The multiplication unit is used to determine the current sampling correction value based on the ratio of the high-frequency sampling value and the average value.

[0009] In one embodiment, the filtering constant of the filtering unit is the second filtering constant.

[0010] In one embodiment, the second filter constant is 100 times the first filter constant.

[0011] In addition, to achieve the above objectives, this application also provides an electronic device, which includes the current sampling circuit described above.

[0012] Furthermore, to achieve the above objectives, this application also provides a current sampling method, which is applied to the electronic device described above, and includes: The sampling voltage is generated based on the output current of the power converter; The sampling voltage is filtered and sampled based on the first filtering constant to obtain a high-frequency sampling value; The sampling voltage is filtered and sampled based on a second filtering constant to obtain a low-frequency sampling value, wherein the second filtering constant is greater than the first filtering constant; The current sampling correction value is determined based on the high-frequency sampling value and the low-frequency sampling value.

[0013] In addition, to achieve the above objectives, embodiments of this application also provide a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the steps of the current sampling method described above.

[0014] This application proposes a current sampling circuit, method, electronic device, and computer-readable storage medium, overcoming the technical problems of inaccurate or slow-responding current sampling schemes. The current sampling circuit includes: a conversion module, the input of which is connected to the output current, and the conversion module is used to generate a sampling voltage based on the output current; a high-frequency filtering sampling module, the input of which is electrically connected to the output of the conversion module, and the high-frequency filtering sampling module is used to filter and sample the sampling voltage based on a first filtering constant to obtain a high-frequency sampling value; a low-frequency filtering sampling module, the input of which is electrically connected to the output of the conversion module, and the low-frequency filtering sampling module is used to filter and sample the sampling voltage based on a second filtering constant to obtain a low-frequency sampling value, wherein the second filtering constant is greater than the first filtering constant; and a calculation module, the calculation module being electrically connected to the outputs of the high-frequency filtering sampling module and the low-frequency filtering sampling module respectively, and the calculation module is used to determine a current sampling correction value based on the high-frequency sampling value and the low-frequency sampling value. This application embodiment uses a high-frequency filtering sampling module and a low-frequency filtering sampling module with different bandwidths to filter and sample the output current of the power converter, obtaining a high-frequency sample value that meets the high bandwidth requirements of loop control, and a low-frequency sample value that can meet the accuracy of the average value of the samples. The high-frequency sample value and the low-frequency sample value are provided to the calculation module to determine the current sampling correction value, thereby achieving the effect of balancing the current sampling accuracy and the high bandwidth requirements of loop control. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of a current sampling circuit provided in an embodiment of this application; Figure 2 This is a schematic diagram of the structure of a current sampling circuit after the conversion module is refined, as provided in an embodiment of this application. Figure 3 This application provides a schematic diagram of the structure of a high-frequency filtering sampling module in a current sampling circuit. Figure 4 This application provides a schematic diagram of the structure of a low-frequency filtering sampling module in a current sampling circuit. Figure 5This is a schematic diagram of the structure of a current sampling circuit after refining the calculation module, as provided in an embodiment of this application. Figure 6 This is a flowchart illustrating a current sampling method provided in an embodiment of this application.

[0017] The realization of the objectives, functional features and advantages of the embodiments of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings.

[0018] Explanation of icon numbers: 100. Conversion module; 200. High-frequency filtering and sampling module; 300. Low-frequency filtering and sampling module; 400. Operation module; R1. First resistor; C1. First capacitor; U1. Operational amplifier; R2. Second resistor; C2. Second capacitor; ADC1. First analog-to-digital converter; R3. Third resistor; C3. Third capacitor; ADC2. Second analog-to-digital converter; 401. Filtering unit; 402. Division unit; 403. Multiplication unit. Detailed Implementation

[0019] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the embodiments of this application.

[0020] The output current ripple of switching power supplies in related technologies is large, thus requiring a filter capacitor to be connected to the output. Current output current sampling schemes either perform sampling before or after capacitor filtering. In the former case, the sampled current is the current after capacitor filtering, which lags behind the converter's output current. When the input voltage changes, causing a change in output current, this sampled value cannot respond quickly. In the latter case, with short filtering times, the output current sampling filter bandwidth is high, but the average value of the sampled output current deviates from the average value of the actual output current; with long filtering times, the output current sampling filter bandwidth is low, unable to respond to current overshoot caused by input voltage jumps. Therefore, the current sampling schemes in related technologies are either unable to respond quickly or are not accurate enough.

[0021] Based on this, embodiments of this application provide a current sampling circuit, method, electronic device, and computer-readable storage medium. The output current of the power converter is filtered and sampled by a high-frequency filtering sampling module and a low-frequency filtering sampling module with different bandwidths to obtain a high-frequency sampling value that meets the high bandwidth requirements of loop control, and a low-frequency sampling value that meets the accuracy of the average value of the sampling. The high-frequency sampling value and the low-frequency sampling value are provided to the calculation module to determine the current sampling correction value, thereby achieving the effect of balancing the accuracy of current sampling and the high bandwidth requirements of loop control.

[0022] The current sampling circuit, method, electronic device, and computer-readable storage medium provided in the embodiments of this application are specifically described through the following embodiments. First, the current sampling circuit in the embodiments of this application is described.

[0023] This application provides a current sampling circuit, referring to... Figure 1 , Figure 1 This is a schematic diagram of a current sampling circuit provided in an embodiment of this application. The current sampling circuit is used to sample the output current of a power converter, and includes: The conversion module 100 has an input terminal connected to the output current and is used to generate a sampling voltage based on the output current. The high-frequency filtering sampling module 200 has its input terminal electrically connected to the output terminal of the conversion module 100. The high-frequency filtering sampling module 200 is used to filter and sample the sampling voltage based on a first filtering constant to obtain a high-frequency sampling value. The low-frequency filtering sampling module 300 has its input terminal electrically connected to the output terminal of the conversion module 100. The low-frequency filtering sampling module 300 is used to filter and sample the sampling voltage based on a second filtering constant to obtain a low-frequency sampling value, wherein the second filtering constant is greater than the first filtering constant. The arithmetic module 400 is electrically connected to the output terminals of the high-frequency filtering sampling module 200 and the low-frequency filtering sampling module 300, respectively. The arithmetic module 400 is used to determine the current sampling correction value based on the high-frequency sampling value and the low-frequency sampling value.

[0024] In this embodiment, the conversion module 100 receives the output current before filtering, that is, the output current before filtering is converted into a sampling voltage, and provided to the high-frequency filtering sampling module 200 and the low-frequency filtering sampling module 300 for filtering and sampling. The first filtering constant of the high-frequency filtering sampling module 200 is relatively small, which can retain the ripple of the switching frequency. Therefore, the high-frequency sampling value obtained may have a large deviation from the average value of the actual output current, but it can meet the high bandwidth requirement of the loop control. The second filtering constant of the low-frequency sampling module 300 is relatively large, and the switching frequency ripple is small and negligible. Therefore, the low-frequency sampling value obtained is basically consistent with the average value of the actual output current, but it does not meet the high bandwidth requirement. Therefore, by providing the high-frequency sampling value and the low-frequency sampling value to the calculation module 400, the defective sampling value can be corrected, so that the current sampling correction value output by the current sampling circuit can take into account both accuracy and high bandwidth requirements.

[0025] Reference Figure 2 In some feasible embodiments, the conversion module 100 described above may include: The first resistor R1 is connected to the first terminal of the output current. The first capacitor C1 has its first terminal connected to the output current, and its second terminal is electrically connected to the second terminal of the first resistor R1. Operational amplifier U1 has its first input terminal electrically connected to the second terminal of the first resistor R1 and the second terminal of the first capacitor C1, its second input terminal electrically connected to the first terminal of the first resistor R1, and its output terminal electrically connected to the input terminals of the high-frequency filtering sampling module 200 and the low-frequency filtering sampling module 300, respectively.

[0026] In this embodiment, the first resistor R1 is a current sampling resistor with a very small resistance, the first capacitor C1 is a current filtering capacitor, and the operational amplifier U1 is used to differentially amplify the voltage across the first resistor R1. Figure 2 As can be seen, the output current sampling in this embodiment is performed before filtering.

[0027] Reference Figure 3 In some feasible embodiments, the high-frequency filtering sampling module 200 described above may include: The first end of the second resistor R2 is electrically connected to the first output end of the conversion module 100. The second capacitor C2 has its first end electrically connected to the second end of the second resistor R2, and its second end electrically connected to the second output terminal of the conversion module 100. The first analog-to-digital converter ADC1 has its first input terminal electrically connected to the first terminal of the second capacitor C2, and its second input terminal electrically connected to the second terminal of the second capacitor C2.

[0028] In this embodiment, the second resistor R2 and the second capacitor C2 can filter the sampling voltage provided by the conversion module 100. The first filtering constant is R2*C2. This filtering constant is small and can retain the ripple of the switching frequency. The high-frequency sampling value can be obtained by performing analog-to-digital conversion on the filtered signal by the first analog-to-digital converter ADC1. However, there is a deviation between this digital value and the average value of the output current after filtering by the power converter. This is because the analog-to-digital converter collects the instantaneous value of the current at a certain moment in the switching cycle. This moment is fixed at a certain moment in the switching cycle. The output current includes the average value, the fundamental frequency of the switching frequency, and its harmonics. Under different voltage and current conditions, the phase and amplitude of each harmonic are different. If the harmonics are not at 0° or 180° at the sampling moment, it will cause a deviation between the sampling value and the output average value.

[0029] Reference Figure 4 In some feasible embodiments, the low-frequency filtering sampling module 300 described above may include: The first end of the third resistor R3 is electrically connected to the first output end of the conversion module 100. The first terminal of the third capacitor C3 is electrically connected to the second terminal of the third resistor R3, and the second terminal of the third capacitor C3 is electrically connected to the second output terminal of the conversion module 100. The second analog-to-digital converter ADC2 has its first input terminal electrically connected to the first terminal of the third capacitor C3, and its second input terminal electrically connected to the second terminal of the third capacitor C3.

[0030] In this embodiment, the third resistor R3 and the third capacitor C3 can filter the sampling voltage provided by the conversion module 100. The second filtering constant is R3*C3. The second filtering constant is greater than the first filtering constant, which makes the switching frequency ripple small and negligible. The low-frequency sampling value can be obtained by performing analog-to-digital conversion on the filtered signal through the second analog-to-digital converter ADC2. The low-frequency sampling value is basically consistent with the average value of the output current after filtering by the power converter.

[0031] Reference Figure 5 In some feasible embodiments, the above-mentioned computing module 400 may include: The input terminal of the filter unit 401 is electrically connected to the output terminal of the high-frequency filtering sampling module 200. The filter unit 401 is used to filter the high-frequency sampling values ​​to obtain the high-frequency sampling average value. The division unit 402 has its input terminals electrically connected to the output terminals of the filter unit 401 and the low-frequency filter sampling module 300, respectively. The division unit 402 is used to determine the average value ratio based on the high-frequency sampling average value and the low-frequency sampling value. The input terminal of the multiplication unit 403 is electrically connected to the output terminal of the high-frequency filtering sampling module 200 and the output terminal of the division unit 402, respectively. The multiplication unit 403 is used to determine the current sampling correction value according to the ratio of the high-frequency sampling value and the average value.

[0032] In this embodiment, the high-frequency sampled value is first filtered by the filtering unit 401 to obtain the high-frequency sampled average value, and then the high-frequency sampled average value is sent to the division unit 402. The division unit 402 divides the low-frequency sampled value by the high-frequency sampled average value. That is, the division unit 402 uses the low-frequency sampled value output by the low-frequency sampling module 300 as the numerator and the high-frequency sampled average value output by the filtering unit 401 as the denominator for the division operation. Since the low-frequency sampled value and the average value of the output current after filtering by the power converter are consistent, the ratio of the high-frequency sampled average value to the average value of the actual output current value can be obtained. Then, the high-frequency sampled value is multiplied by the average value ratio by the multiplication unit 403 to obtain the current sampling correction value that is consistent with the average value of the output current after filtering by the power converter. Moreover, the time constant of the current sampling correction value is the same as the first filtering constant, so while ensuring accuracy, it can also meet the high bandwidth requirements.

[0033] In some feasible embodiments, the filtering constant of the filtering unit 401 is the second filtering constant.

[0034] As an example, in conjunction with the above Figure 4 and Figure 5 In a corresponding embodiment, the filtering constant of the filtering unit 401 can be R3*C3, i.e., the second filtering constant, and the filtering unit 401 can be expressed as follows: .

[0035] In some feasible embodiments, the second filter constant is 100 times the first filter constant.

[0036] As an example, in conjunction with the above Figure 3 and Figure 4 In the corresponding embodiment, the second filter constant R3*C3 can be 100 times the first filter constant R2*C2, and the ratio between the two can also be adjusted according to the actual situation. This embodiment does not impose any restrictions on this.

[0037] In addition, this application also provides an electronic device that includes the current sampling circuit provided in the above embodiments.

[0038] The electronic device proposed in this embodiment belongs to the same technical concept as the current sampling circuit proposed in the above embodiments. Technical details not described in detail in this embodiment can be found in any of the above embodiments. Furthermore, this embodiment has the same beneficial effects as the above embodiments of the current sampling circuit, and will not be elaborated here.

[0039] Furthermore, this application also provides a current sampling method, which is applied to the above-mentioned electronic device, with reference to... Figure 6 , Figure 6 This is a flowchart illustrating a current sampling method provided in an embodiment of this application, including steps S10 to S40.

[0040] Step S10: Generate a sampling voltage based on the output current of the power converter; Step S20: Filter and sample the sampled voltage based on the first filter constant to obtain a high-frequency sampled value; Step S30: Filter and sample the sampled voltage based on the second filter constant to obtain a low-frequency sampled value, wherein the second filter constant is greater than the first filter constant; Step S40: Determine the current sampling correction value based on the high-frequency sampling value and the low-frequency sampling value.

[0041] The current sampling method proposed in this embodiment belongs to the same technical concept as the electronic device proposed in the above embodiments. Technical details not described in detail in this embodiment can be found in any of the above embodiments. Furthermore, this embodiment has the same beneficial effects as the above embodiments, and will not be elaborated here.

[0042] Furthermore, embodiments of this application also provide a computer-readable storage medium, which may be a non-volatile computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, it implements the current sampling method provided in any of the above embodiments.

[0043] The computer-readable storage medium provided in this application may be, for example, a USB flash drive, but is not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems or devices, or any combination thereof. More specific examples of computer-readable storage media may include, but are not limited to: electrical connections having one or more wires, portable computer disks, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM or flash memory), optical fiber, portable compact disk read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof. In this embodiment, the computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in conjunction with an instruction execution system or device. The program code contained on the computer-readable storage medium may be transmitted using any suitable medium, including but not limited to: wires, optical cables, RF (Radio Frequency), etc., or any suitable combination thereof.

[0044] The aforementioned computer-readable storage medium may be included in an electronic device or may exist independently without being assembled into an electronic device.

[0045] The aforementioned computer-readable storage medium carries one or more programs, which, when executed by an electronic device, enable the electronic device to implement the aforementioned current sampling method.

[0046] Computer program code for performing the operations of this application can be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, and C++, and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving remote computers, the remote computer can be connected to the user's computer via any type of network—including a Local Area Network (LAN) or a Wide Area Network (WAN)—or can be connected to an external computer (e.g., via the Internet using an Internet service provider).

[0047] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code containing one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions indicated in the blocks may occur in a different order than those indicated in the drawings. For example, two consecutively indicated blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or operation, or using a combination of dedicated hardware and computer instructions.

[0048] The modules described in the embodiments of this application can be implemented in software or hardware. The names of the modules do not necessarily limit the functionality of the unit itself.

[0049] The readable storage medium provided in this embodiment is a computer-readable storage medium, which stores computer-readable program instructions (i.e., computer program) for performing the above-described current sampling method. The beneficial effects of the computer-readable storage medium provided in this application are the same as the beneficial effects of the current sampling method provided in the above-described embodiments, and will not be repeated here.

[0050] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of this application are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0051] Furthermore, in the embodiments of this application, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of the embodiments of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified. Additionally, the meaning of "and / or" throughout the text includes three parallel solutions; for example, "A and / or B" includes solution A, solution B, or a solution that simultaneously satisfies A and B.

[0052] In the embodiments of this application, unless otherwise expressly specified and limited, the terms "connection" and "fixed" should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application according to the specific circumstances.

[0053] It should also be understood that references to "one embodiment" or "some embodiments" in the specification of embodiments of this application mean that one or more embodiments of this application include the specific features, structures, or characteristics described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof all mean "including but not limited to," unless otherwise specifically emphasized.

[0054] It should be noted that the technical solutions of the various embodiments of this application can be combined with each other, but only if they are implemented by those skilled in the art. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the embodiments of this application.

[0055] The above are merely optional embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the description and drawings of this application, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A current sampling circuit, characterized in that, The current sampling circuit is used to sample the output current of the power converter, including: A conversion module, wherein the input terminal of the conversion module is connected to the output current, and the conversion module is used to generate a sampling voltage based on the output current; A high-frequency filtering sampling module, wherein the input terminal of the high-frequency filtering sampling module is electrically connected to the output terminal of the conversion module, and the high-frequency filtering sampling module is used to filter and sample the sampling voltage based on a first filtering constant to obtain a high-frequency sampling value; A low-frequency filtering sampling module, wherein the input terminal of the low-frequency filtering sampling module is electrically connected to the output terminal of the conversion module, and the low-frequency filtering sampling module is used to filter and sample the sampling voltage based on a second filtering constant to obtain a low-frequency sampling value, wherein the second filtering constant is greater than the first filtering constant; The arithmetic module is electrically connected to the output terminals of the high-frequency filtering sampling module and the low-frequency filtering sampling module, respectively. The arithmetic module is used to determine the current sampling correction value based on the high-frequency sampling value and the low-frequency sampling value.

2. The current sampling circuit as described in claim 1, characterized in that, The conversion module includes: A first resistor, with its first end connected to the output current; A first capacitor, with its first terminal connected to the output current and its second terminal electrically connected to the second terminal of the first resistor; An operational amplifier, wherein the first input terminal of the operational amplifier is electrically connected to the second terminal of the first resistor and the second terminal of the first capacitor, the second input terminal of the operational amplifier is electrically connected to the first terminal of the first resistor, and the output terminal of the operational amplifier is electrically connected to the input terminal of the high-frequency filtering sampling module and the input terminal of the low-frequency filtering sampling module, respectively.

3. The current sampling circuit as described in claim 1, characterized in that, The high-frequency filtering sampling module includes: The second resistor has its first end electrically connected to the first output terminal of the conversion module. The second capacitor has its first terminal electrically connected to the second terminal of the second resistor, and its second terminal electrically connected to the second output terminal of the conversion module. A first analog-to-digital converter (ADC) is provided, wherein a first input terminal of the first ADC is electrically connected to a first terminal of the second capacitor, and a second input terminal of the first ADC is electrically connected to a second terminal of the second capacitor.

4. The current sampling circuit as described in claim 1, characterized in that, The low-frequency filtering sampling module includes: The third resistor, the first end of which is electrically connected to the first output terminal of the conversion module; The third capacitor has its first terminal electrically connected to the second terminal of the third resistor, and its second terminal electrically connected to the second output terminal of the conversion module. A second analog-to-digital converter (ADC) is connected to a first terminal of a third capacitor, and a second terminal of the second ADC is connected to a second terminal of the third capacitor.

5. The current sampling circuit as described in claim 1, characterized in that, The computing module includes: A filtering unit, the input of which is electrically connected to the output of the high-frequency filtering sampling module, is used to filter the high-frequency sampled values ​​to obtain the high-frequency sampled average value; The division unit has its input terminals electrically connected to the output terminals of the filtering unit and the low-frequency filtering sampling module, respectively. The division unit is used to determine the average value ratio based on the high-frequency sampling average value and the low-frequency sampling value. The multiplication unit has its input terminals electrically connected to the output terminals of the high-frequency filtering sampling module and the division unit, respectively. The multiplication unit is used to determine the current sampling correction value based on the ratio of the high-frequency sampling value and the average value.

6. The current sampling circuit as described in claim 5, characterized in that, The filtering constant of the filtering unit is the second filtering constant.

7. The current sampling circuit as described in any one of claims 1 to 6, characterized in that, The second filter constant is 100 times the first filter constant.

8. An electronic device, characterized in that, The electronic device includes a current sampling circuit as described in any one of claims 1 to 7.

9. A current sampling method, characterized in that, The current sampling method is applied to the electronic device as described in claim 8, comprising: The sampling voltage is generated based on the output current of the power converter; The sampling voltage is filtered and sampled based on the first filtering constant to obtain a high-frequency sampling value; The sampling voltage is filtered and sampled based on a second filtering constant to obtain a low-frequency sampling value, wherein the second filtering constant is greater than the first filtering constant; The current sampling correction value is determined based on the high-frequency sampling value and the low-frequency sampling value.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the steps of the current sampling method as described in claim 9.

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