ADC (Analog to Digital Converter) acquisition circuit and equipment

Abstract

The embodiment of the invention provides an ADC acquisition circuit and device. The circuit comprises a calibration module connected to a signal source, an ADC module connected to the calibration module, and a controller connected to the calibration module and the ADC module. The signal source is used for outputting a first test voltage signal and a second test voltage signal in sequence; the calibration module is used for measuring a first voltage value corresponding to the first test voltage signal and measuring a second voltage value corresponding to the second test voltage signal; the ADC module is used for collecting the first test voltage signal and the second test voltage signal transmitted by the calibration module to obtain a first numerical value and a second numerical value; the controller is used for determining a calibration value according to a first difference value between the first voltage value and the second voltage value and a second difference value between the first numerical value and the second numerical value; and the controller is also used for calibrating the signal value acquired by the ADC module according to the calibration value, and the acquisition precision of the ADC module is improved by performing error calibration on the ADC module.

Description

Technical Field

[0001] This application relates to the technical field of signal conversion, and particularly to an ADC acquisition circuit and device. Background Art

[0002] An ADC (Analog-to-Digital Converter) acquisition circuit is a key electronic component that bridges the gap between analog and digital signals. The core function of such a circuit is to convert continuous analog voltage or current signals into discrete digital codes so that digital systems can process, store, or transmit this information. In practical applications, ADC acquisition circuits are widely used in various electronic devices, including data acquisition systems, communication systems, automatic control systems, and various measuring instruments, etc.

[0003] However, with the increasing demand for precision in the fields of industrial production and testing, traditional ADC acquisition circuits have gradually shown their limitations and cannot meet the wide range of requirements in actual production and testing. For example, in the fields of precision measuring instruments, medical devices, high-end communication systems, and new energy vehicles, even minor signal changes may carry important information or directly affect the performance and safety of the device. If the acquisition accuracy of the ADC is insufficient, these subtle differences cannot be accurately captured, resulting in data distortion, analysis errors, and even serious safety failures may be triggered. Summary of the Invention

[0004] The main objective of the embodiments of this application is to propose an ADC acquisition circuit and device, aiming to improve the acquisition accuracy of the ADC module.

[0005] To achieve the above objective, a first aspect of the embodiments of this application proposes an ADC acquisition circuit. The circuit includes a signal source, a calibration module, an ADC module, and a controller. Among them, the calibration module is connected to the signal source, the ADC module is connected to the calibration module, and the controller is connected to the calibration module and the ADC module;

[0006] The signal source is used to output a first test voltage signal and a second test voltage signal successively;

[0007] The calibration module is used to measure a first voltage value corresponding to the first test voltage signal and a second voltage value corresponding to the second test voltage signal;

[0008] The ADC module is used to acquire the first test voltage signal and the second test voltage signal transmitted by the calibration module, and obtain a first value and a second value;

[0009] The controller is used to determine a calibration value according to a first difference between the first voltage value and the second voltage value, and a second difference between the first value and the second value;

[0010] The controller is further configured to calibrate the signal value collected by the ADC module according to the calibration value.

[0011] By means of the method provided in the first aspect, the problem that the acquisition accuracy of the existing ADC module cannot meet the requirements of actual production testing is solved, and the problem that due to insufficient acquisition accuracy of the ADC module, the subtle differences of the test products cannot be captured, resulting in data distortion, analysis errors, and even safety failures is avoided. By performing error calibration on the ADC module, offset error, gain error, non-linear error, etc. can be reduced or eliminated, ensuring a high degree of consistency and accuracy between the acquisition value of the ADC module and the actually input analog signal, and improving the acquisition accuracy of the ADC module.

[0012] In a possible implementation manner, the circuit further includes a reverse attenuation module, connected to the output end of the calibration module and the input end of the ADC module, for proportionally reducing the first test voltage signal and the second test voltage signal, and outputting a reduced first test voltage signal and a reduced second test voltage signal.

[0013] In a possible implementation manner, the reverse attenuation module includes a first resistor, a second resistor, and a first operational amplifier. The first end of the first operational amplifier is grounded, the second end is connected to the first ends of the first resistor and the second resistor, and the third end is connected to the second end of the second resistor.

[0014] In a possible implementation manner, the circuit further includes a voltage follower module, connected to the output end of the reverse attenuation module and the input end of the ADC module, for isolating the reverse attenuation module and the ADC module, and transmitting the reduced first test voltage signal and the reduced second test voltage signal to the ADC module.

[0015] In a possible implementation manner, the voltage follower module includes a second operational amplifier, and the first end of the second operational amplifier is connected to the third end, and the second end is connected to the third end of the first operational amplifier.

[0016] In a possible implementation manner, the circuit further includes a storage module; the controller is further configured to store the calibration value in the storage module after determining the calibration value; the controller is further configured to retrieve the calibration value from the storage module to calibrate the signal value collected by the ADC module according to the calibration value.

[0017] In a possible implementation manner, the calibration module includes a multimeter, configured to measure a first voltage value corresponding to the first test voltage signal, and measure a second voltage value corresponding to the second test voltage signal.

[0018] In a possible implementation, the calibration value includes a slope value and an offset value, and is determined based on the following formula:

[0019]

[0020] where K represents the slope value, C represents the offset value, U a represents the first voltage value, and U b represents the second voltage value, A represents the first numerical value, and B represents the second numerical value.

[0021] In a possible implementation, the signal value collected by the ADC module is calibrated based on the following formula:

[0022] V = D × K + C;

[0023] where V represents the expected output voltage value, D represents the signal value collected by the ADC module, K represents the slope value, and C represents the offset value.

[0024] In a second aspect, an electronic device is provided, and when the electronic device is executed, it implements the ADC acquisition circuit in any possible implementation manner in the first aspect.

[0025] As can be seen from the technical solutions provided by one or more embodiments of the present specification above, for the ADC acquisition circuit provided by the embodiments of the present application, the calibration module is connected to the signal source, the ADC module is connected to the calibration module, and the controller is connected to the calibration module and the ADC module; the signal source is used to output a first test voltage signal and a second test voltage signal in sequence; the calibration module is used to measure the first voltage value corresponding to the first test voltage signal and measure the second voltage value corresponding to the second test voltage signal; the ADC module is used to collect the first test voltage signal and the second test voltage signal transmitted by the calibration module to obtain a first numerical value and a second numerical value; the controller is used to determine the calibration value according to the first difference between the first voltage value and the second voltage value and the second difference between the first numerical value and the second numerical value; the controller is further used to calibrate the signal value collected by the ADC module according to the calibration value. By performing error calibration on the ADC module, offset error, gain error, and non-linear error can be reduced or eliminated, ensuring a high degree of consistency and accuracy between the collected value of the ADC module and the actually input analog signal, and improving the acquisition accuracy of the ADC module. Description of the Drawings

[0026] To more clearly illustrate the technical solutions in one or more embodiments of this specification or the prior art, the following will briefly introduce the drawings required for the description of one or more embodiments or the prior art. Obviously, the drawings described below are only some embodiments recorded in this specification. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0027] Figure 1 is the first structural schematic diagram of the ADC acquisition circuit provided by an embodiment of the present application;

[0028] Figure 2 is the second structural schematic diagram of the ADC acquisition circuit provided by an embodiment of the present application;

[0029] Figure 3 is the circuit schematic diagram of the voltage follower module and the reverse attenuation module provided by an embodiment of the present application.

[0030] Reference numerals: first resistor R1, second resistor R2, first operational amplifier D1, second operational amplifier D2. Detailed implementation manners

[0031] In order to enable those skilled in the art of this technology to better understand the technical solutions in this specification, the following will clearly and completely describe the technical solutions in one or more embodiments of this specification in combination with the drawings in one or more embodiments of this specification. Obviously, the described one or more embodiments are only a part of the embodiments of this specification, rather than all the embodiments. Based on one or more embodiments in this specification, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of this document.

[0032] It should be noted that although the functional modules are divided in the device schematic diagram and the logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in a different order from the module division in the device or the order in the flowchart. Terms such as "first" and "second" in the specification, claims, and the above drawings are used to distinguish similar objects and do not necessarily need to be used to describe a specific order or sequence.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those skilled in the technical field to which this application belongs. The terms used herein are only for the purpose of describing the embodiments of this application and are not intended to limit this application.

[0034] In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other. The embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0035] In a first aspect, as Figure 1 shown, an ADC acquisition circuit is provided. The circuit includes a signal source, a calibration module, an ADC module, and a controller. Among them, the calibration module is connected to the signal source, the ADC module is connected to the calibration module, and the controller is connected to the calibration module and the ADC module; the signal source is configured to output a first test voltage signal and a second test voltage signal successively; the calibration module is configured to measure a first voltage value corresponding to the first test voltage signal and measure a second voltage value corresponding to the second test voltage signal; the ADC module is configured to acquire the first test voltage signal and the second test voltage signal transmitted by the calibration module to obtain a first value and a second value; the controller is configured to determine a calibration value according to a first difference between the first voltage value and the second voltage value and a second difference between the first value and the second value; the controller is further configured to calibrate the signal value acquired by the ADC module according to the calibration value.

[0036] It should be noted that the main function of the ADC is to convert analog signals into digital signals. If there are errors in the ADC, the converted digital signals will not be able to accurately reflect the original analog signals. Such inaccurate data acquisition may lead to the system making wrong decisions or generating misleading analysis results, and will also cause the system stability to decline. For example, if the reference voltage source of the ADC is unstable or drifts, the acquisition values of the ADC will change over time, thus affecting the system stability. In addition, unstable factors in the front-end signal processing circuit may also cause an increase in ADC errors, further affecting the system stability. ADC errors may also lead to the deterioration of signal quality. This is manifested as signal distortion, increased noise, or changes in signal strength, etc. These changes may make the signals difficult to be accurately identified or processed, thus affecting the overall performance of the system. Calibrating the ADC module can improve the measurement accuracy of the ADC module. In practical applications, the performance of the ADC may be affected by various factors, such as temperature changes, aging, power fluctuations, manufacturing tolerances, and mismatches between channels, etc. These factors may all cause the ADC to generate offset errors, gain errors, nonlinear errors, etc. By reducing or eliminating offset errors, gain errors, and nonlinear errors, etc., it is ensured that there is a high degree of consistency and accuracy between the acquisition values of the ADC module and the actually input analog signals. This not only helps to compensate for the possible tolerances in the manufacturing process, but also makes the ADC modules of different batches more consistent in performance. At the same time, ADC calibration can also improve the anti-interference ability of the system. In a complex and changeable working environment, such as temperature changes, electromagnetic interference, high-frequency noise, etc., the performance of the ADC module may be affected. Through calibration, the ADC module can quickly adapt to these environmental changes, reduce the influence of external factors on the measurement results, and thus ensure the long-term stable operation of the system. Moreover, calibration can also extend the service life of the ADC module. By compensating for the possible performance degradation over time, it is ensured that the ADC module maintains high precision and stability for a longer time.

[0037] It should also be noted that since the numerical value of the voltage acquired by the ADC and the acquired voltage value satisfy a linear function relationship, it is necessary to make the signal source output the first test voltage signal and the second test voltage signal successively. The calibration module measures the first voltage value corresponding to the first test voltage signal and measures the second voltage value corresponding to the second test voltage signal. The ADC module acquires the first test voltage signal and the second test voltage signal transmitted by the calibration module to obtain a first numerical value and a second numerical value. The calibration value can be determined based on the first voltage value, the second voltage value, the first numerical value, and the second numerical value.

[0038] The method provided by the first aspect solves the problem that the acquisition accuracy of the existing ADC module cannot meet the requirements of actual production tests, and avoids the problems of data distortion, analysis errors, and even safety failures caused by the inability of the ADC module to capture the subtle differences of the test products due to insufficient acquisition accuracy. By calibrating the errors of the ADC module, it is possible to reduce or eliminate offset errors, gain errors, and non-linear errors, etc., ensuring a high degree of consistency and accuracy between the acquisition value of the ADC module and the actually input analog signal, and improving the acquisition accuracy of the ADC module.

[0039] In a possible implementation manner, the circuit further includes a reverse attenuation module, connected to the output end of the calibration module and the input end of the ADC module, for proportionally reducing the first test voltage signal and the second test voltage signal, and outputting a reduced first test voltage signal and a reduced second test voltage signal.

[0040] It should be noted that the purpose of the reverse attenuation module to proportionally reduce the first test voltage signal and the second test voltage signal is to make the output signal amplitude within the required range. The input range of the traditional ADC acquisition circuit is usually small, mainly reflected in its limitation on the input voltage of the analog signal. Specifically, the input range of the ADC is usually determined by its reference voltage and internal circuit design, and is generally within a certain specific voltage range. Within this range, the ADC can convert the analog signal into the corresponding digital signal. However, due to the small input range of the traditional ADC, it cannot cover the wide voltage range in some industrial applications. For example, in some high-voltage or low-voltage environments, the analog signal to be collected may exceed the input range of the ADC, resulting in signal distortion or incorrect acquisition. In this application, the reverse attenuation module is used to proportionally reduce the input signal. By reducing the input signal to within the input range of the ADC, the ADC can adapt to the voltage ranges of different signal sources, thereby increasing the flexibility and versatility of the system. It can not only ensure that the signal is correctly sampled and converted, avoiding distortion or damage caused by the signal exceeding the input range of the ADC, but also make the resolution of the ADC more refined. The resolution of the ADC refers to the minimum voltage change amount that it can distinguish, which is usually related to the number of bits and the input range of the ADC. For a given number of bits of the ADC, the smaller the input range, the smaller the voltage value represented by each least significant bit. For example, if the resolution of the ADC is 12 bits and the input range is 0-5V, then the voltage value represented by each least significant bit will be smaller than when the input range is 0-10V. Therefore, under the same voltage change, reducing the input range can provide more quantization levels, thereby improving the measurement accuracy. At the same time, in some cases, the input signal may contain noise. By reducing the input signal range, the influence of noise on the ADC conversion result can be relatively reduced.

[0041] In a possible implementation, as Figure 3 shown, the reverse attenuation module includes a first resistor R1, a second resistor R2, and a first operational amplifier D1. The first terminal of the first operational amplifier D1 is grounded, the second terminal is connected to the first terminals of the first resistor R1 and the second resistor R2, and the third terminal is connected to the second terminal of the second resistor R2.

[0042] In some embodiments, the first operational amplifier D1 provides a reverse amplification function. The input signal is connected to the second terminal of the first operational amplifier D1 through the first resistor R1. The second resistor R2 is a feedback resistor. The third terminal of the first operational amplifier D1 is connected to its second terminal through the second resistor R2 to form a negative feedback loop. The first terminal of the first operational amplifier D1 is grounded to ensure the stability of the common-mode voltage of the circuit. The input signal forms a voltage division between the first resistor R1 and the second resistor R2. However, due to the negative feedback effect of the first operational amplifier D1, there is an inverse proportional relationship between the output signal and the input signal. Among them, the resistance values of the first resistor R1 and the second resistor R2 should be selected according to the required attenuation amount and the stability of the circuit. The attenuation amount is determined by the resistance ratio of the first resistor R1 and the second resistor R2. Specifically, the resistance value of the first resistor R1 is greater than that of the second resistor R2 to achieve signal attenuation.

[0043] In a possible implementation, as Figure 2 shown, the circuit further includes a voltage follower module, connected to the output terminal of the reverse attenuation module and the input terminal of the ADC module, for isolating the reverse attenuation module and the ADC module, and transmitting the reduced first test voltage signal and the reduced second test voltage signal to the ADC module.

[0044] It should be noted that the voltage follower module isolates the reverse attenuation module and the ADC module, which can eliminate or reduce the influence of electrical noise, electromagnetic interference, and ground potential difference on the signal, ensure the stability and accuracy of the signal, avoid signal interference during transmission, and protect the circuit and equipment from damage caused by electrical noise and interference, thereby improving the performance and reliability of the entire system. In addition, the voltage follower module can isolate the reverse attenuation module and the ADC module, which helps prevent current from flowing directly from one circuit into another, thus avoiding possible short circuits and damage. Without isolation, the noise and interference signals in the reverse attenuation module may be directly transmitted to the ADC module, affecting the signal quality and stability. The voltage follower module transfers the input signal to the output end through its follower characteristics, suppressing the noise and interference in the input circuit. At the same time, the load of the ADC module may affect the reverse attenuation unit, resulting in distortion or change of the input signal. The high output impedance and low input impedance characteristics of the voltage follower module help reduce this load effect, making the input signal more stable. In addition, the dynamic ranges of the reverse attenuation module and the ADC module may be different. Direct connection may cause the signal to be truncated or distorted during transmission, and may also lead to circuit instability, generating oscillation or self-excitation phenomena. The voltage follower module can provide appropriate gain to ensure the integrity and accuracy of the signal during transmission, and can also help stabilize the working state of the circuit through its internal negative feedback mechanism, preventing oscillation and self-excitation phenomena from occurring.

[0045] In a possible implementation, as Figure 3 shown, the voltage follower module includes a second operational amplifier D2. The first end and the third end of the second operational amplifier D2 are connected, and the second end is connected to the third end of the first operational amplifier D1.

[0046] It should be noted that the voltage follower module can isolate the reverse attenuation module and the ADC module through the second operational amplifier D2, which helps prevent current from flowing directly from one circuit into another, thus avoiding possible short circuits and damage. Without isolation, the noise and interference signals in the reverse attenuation module may be directly transmitted to the ADC module, affecting the signal quality and stability. The voltage follower module transmits the input signal to the output end through its following characteristic, suppressing the noise and interference in the input circuit. At the same time, the load of the ADC module may affect the reverse attenuation module, resulting in distortion or change of the input signal. The high output impedance and low input impedance characteristics of the voltage follower module help reduce this load effect, making the input signal more stable. In addition, the dynamic ranges of the reverse attenuation module and the ADC module may be different. Direct connection may cause the signal to be truncated or distorted during transmission, as well as lead to circuit instability, resulting in oscillation or self-excitation phenomena. The voltage follower module can provide appropriate gain to ensure that the signal maintains its integrity and accuracy during transmission. It can also, through its internal negative feedback mechanism, help stabilize the working state of the circuit and prevent the occurrence of oscillation and self-excitation phenomena.

[0047] In a possible implementation manner, the circuit further includes a storage module; the controller is further configured to store the calibration value in the storage module after determining the calibration value; the controller is further configured to retrieve the calibration value from the storage module to calibrate the signal value collected by the ADC module according to the calibration value.

[0048] It should be noted that by calibrating the signal value collected by the ADC module, the gain error or offset error of the ADC module can be significantly reduced or eliminated, improving the accuracy of the result and making the measured value closer to the true value. The calibrated ADC module can stably collect accurate data, enhancing the credibility and reliability of the data.

[0049] Among them, the controller is used to retrieve the calibration value from the storage module to calibrate the signal value collected by the ADC module according to the calibration value, obtain the expected output voltage value, and store the expected output voltage value in the memory for easy access to the historical expected output voltage value, thereby performing data analysis and processing, and further optimizing and adjusting the system to improve the performance and stability of the system. At the same time, it can also continuously monitor the system state. By regularly analyzing the historical target data, anomalies or faults in the system can be detected in a timely manner, the cause of the fault can be investigated and located, and corresponding measures can be taken for repair. In addition, storing the expected output voltage value in the memory also facilitates data sharing with other systems or devices, enabling collaborative cooperation and data exchange between different systems or devices.

[0050] It should also be noted that the storage module includes a memory, and the memory includes a Flash memory. The Flash memory is a non-volatile memory that can meet the needs of large-capacity data storage and has the characteristic of being able to retain the stored data even without power supply. This characteristic enables the Flash memory to ensure that the data will not be lost even when the device is powered off or shut down, thus ensuring the persistence and reliability of the data. Compared with traditional hard disks, the Flash memory has a faster read / write speed, making it more efficient in processing large amounts of data and helping to improve the overall performance of the system. At the same time, the Flash memory also has the characteristics of anti-vibration and anti-shock resistance and can be applied to harsh environments. Since the Flash memory has no mechanical moving parts, it has low power consumption, and the Flash memory can withstand multiple writes and erasures, having high flexibility. Additionally, it can be understood that the embodiments of the present application do not limit the type of memory.

[0051] In a possible implementation manner, the calibration module includes a multimeter for measuring a first voltage value corresponding to the first test voltage signal and a second voltage value corresponding to the second test voltage signal.

[0052] It should be noted that a multimeter can accurately convert a voltage signal into a digital reading. By selecting an appropriate range and resolution, the multimeter can provide very accurate voltage measurement values. The multimeter is built-in with various error compensation mechanisms, such as automatic zero calibration, non-linear error correction, etc. These mechanisms can significantly reduce the systematic error in the measurement process. When using a multimeter for measurement, the measurement personnel should use the multimeter in a standardized manner, such as waiting for the reading to stabilize before recording and avoiding measurement in a strong electromagnetic interference environment, etc., to further reduce the random error. At the same time, the multimeter allows real-time monitoring of the output voltage of the adjustable constant voltage source, facilitating the measurement personnel to adjust the adjustable constant voltage source to obtain the required voltage value.

[0053] In a possible implementation manner, the calibration value includes a slope value and an offset value and is determined based on the following formula:

[0054]

[0055] where K represents the slope value, C represents the offset value, U a represents the first voltage value, U b represents the second voltage value, A represents the first numerical value, and B represents the second numerical value.

[0056] It should be noted that the K value and the C value are calibration values. Among them, the K value is the slope value, which represents the amount of voltage increase when the ADC increases by one unit value. The C value is the offset value, which means that when the ADC samples a signal voltage value of 0, the corresponding voltage value may theoretically be 0, but it may also deviate due to the offset or non-linear characteristics of the ADC. During the ADC conversion process, there are gain errors and offset errors. The gain error will cause the proportional relationship between the output digital code and the input voltage to deviate from the ideal value, while the offset error will cause the output digital code to be non-zero even when the input voltage is 0. By the slope value K, the sampling value of the ADC can be adjusted to make it in the correct proportional relationship with the input signal; by the offset value C, the sampling value of the ADC can be adjusted to eliminate the continuous difference between the actual sampling value and the theoretical sampling value of the ADC, that is, the problem of the displacement of the entire transfer function.

[0057] It should also be noted that after obtaining the calibration values, including verifying the calibration values, the verification process specifically includes: selecting at least one known accurate input signal, using the calibrated ADC module to measure these input signals, and recording their sampling values. According to the slope value K and the offset value C obtained during the calibration process, calculate the theoretically sampled signal value of the ADC, and compare the actually measured ADC sampled signal value with the theoretical value. If the difference between the actually measured value and the theoretical value is within the acceptable range, the verification passes; if the difference exceeds the acceptable range, it is necessary to re-check the calibration process, including the accuracy of the input signal, the accuracy of the calibration equipment, and the correctness of the calibration steps. Calibrating the ADC module can improve the sampling accuracy of the ADC module. By reducing or eliminating offset errors, gain errors, and non-linear errors, etc., it ensures a high degree of consistency and accuracy between the sampling value of the ADC module and the actually input analog signal. This not only helps to compensate for the possible tolerances in the manufacturing process, but also makes the performance of different batches of ADC modules more consistent. At the same time, in a complex and changeable working environment, such as temperature changes, electromagnetic interference, etc., the performance of the ADC module may be affected. Through calibration, the ADC module can quickly adapt to these environmental changes, reduce the influence of external factors on the measurement results, and thus ensure the long-term stable operation of the system. Moreover, calibration can also extend the service life of the ADC module. By compensating for the possible performance degradation over time, it ensures that the ADC module maintains high accuracy and stability for a longer time.

[0058] In a possible implementation manner, the signal value sampled by the ADC module is calibrated based on the following formula:

[0059] V = D × K + C.

[0060] Wherein, V represents the expected output voltage value, D represents the signal value sampled by the ADC module, K represents the slope value, and C represents the offset value.

[0061] In some embodiments, it should be noted that the slope value refers to the proportional deviation between the actual output and the ideal output of the ADC, which usually manifests as the amplification or reduction of the output signal, while the offset value is the fixed deviation between the actual output and the ideal output of the ADC, which causes the offset of the output signal in the vertical direction. According to the slope value K and the offset value C obtained during the calibration process, the acquisition value of the ADC can be adjusted to make it have a correct proportional relationship with the input signal, and to eliminate the continuous difference between the actual acquisition value and the theoretical acquisition value of the ADC, that is, the problem of the displacement of the entire transfer function. Specifically, it includes multiplying the ADC acquisition value by the slope value K to adjust its gain, compensating for the gain error of the ADC module, obtaining the gain-adjusted output value, and subtracting the offset value C from the gain-adjusted output value to eliminate its offset error, thereby compensating for the offset error of the ADC module and obtaining the desired output voltage value. By compensating the slope value K and the offset value C of the ADC module, the acquisition accuracy of the ADC can be improved. In a data acquisition system, the accuracy of the ADC directly determines the minimum signal change and resolution that the system can measure. By compensating these errors, the quantization error and total error of the ADC can be reduced, thereby improving the measurement accuracy and resolution of the system. This helps to achieve more accurate data acquisition and more accurate signal processing, and can also enhance the stability of the system. During long-term operation or in a complex environment, the performance of the ADC may change due to factors such as temperature, humidity, and electromagnetic interference. By compensating these errors, the fluctuations and drifts of the ADC-acquired signal can be reduced, thereby improving the stability and reliability of the system. This helps to ensure that the system can maintain accurate data acquisition and stable performance under various conditions. Accurate ADC acquisition values can provide a more reliable signal quality assessment, which helps to optimize signal processing algorithms. In a signal processing system, the performance and accuracy of the algorithm largely depend on the quality of the input signal. By compensating for the gain error and offset error, the accuracy and reliability of the ADC-acquired signal can be improved, thereby providing a more accurate and reliable input signal for the signal processing algorithm, helping to optimize the performance of the algorithm, and improving the accuracy and efficiency of signal processing. In addition, accurate ADC acquisition values can reduce system failures and maintenance costs caused by errors.

[0062] In a second aspect, an electronic device is provided, and when the electronic device is executed, it implements the ADC acquisition circuit described in any possible implementation manner in the first aspect.

[0063] The electronic device provided by the second aspect solves the problem that the acquisition accuracy of the existing ADC module cannot meet the actual production test requirements, and avoids the problems of data distortion, analysis errors, and even safety failures caused by the insufficient acquisition accuracy of the ADC module, which cannot capture the subtle differences of the test products. By performing error calibration on the ADC module, offset error, gain error, non-linear error, etc. can be reduced or eliminated, ensuring a high degree of consistency and accuracy between the acquisition value of the ADC module and the actually input analog signal, and improving the acquisition accuracy of the ADC module.

[0064] The system architecture and application scenarios described in the embodiments of this application are to more clearly illustrate the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided by the embodiments of this application. Those skilled in the art know that with the evolution of the system architecture and the emergence of new application scenarios, the technical solutions provided by the embodiments of this application are equally applicable to similar technical problems.

[0065] Those of ordinary skill in the art can understand that all or part of the processes of implementing the methods in the above embodiments can be completed by instructing relevant hardware through a computer program. The computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above methods. Among them, any reference to memory, storage, database, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and Rambus dynamic RAM (RDRAM), etc.

[0066] Those of ordinary skill in the art will understand that all or some of the steps and systems disclosed above in the methods can be implemented as software, firmware, hardware, and appropriate combinations thereof. Some physical components or all physical components can be implemented as software executed by a processor, such as a central processing unit, a digital signal processor, or a microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit. Such software can be distributed on a computer-readable medium, which can include a computer storage medium (or non-transitory medium) and a communication medium (or transitory medium). As is well known to those of ordinary skill in the art, the term computer storage medium includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information, such as computer-readable instructions, data structures, program modules, or other data. Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disk (DVD) or other optical disk storage, magnetic cassettes, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to store the desired information and can be accessed by a computer. In addition, as is well known to those of ordinary skill in the art, a communication medium typically includes computer-readable instructions, data structures, program modules, or other data in a modulated data signal such as a carrier wave or other transmission mechanism, and can include any information delivery medium.

[0067] The above has illustrated some embodiments of the present application with reference to the accompanying drawings, and thus does not limit the scope of the rights of the present invention. Any modifications, equivalent replacements, and improvements made by those skilled in the art without departing from the scope and essence of the present invention shall be within the scope of the rights of the present application.

[0068] Those of ordinary skill in the art will understand that all or some of the steps, systems, and functional modules / units in the devices in the methods disclosed above can be implemented as software, firmware, hardware, and appropriate combinations thereof.

[0069] The terms "first", "second", "third", "fourth", etc. (if any) in the specification of the present application and the above accompanying drawings are used to distinguish similar objects and do not necessarily need to be used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances so that the embodiments of the present application described here can be implemented in an order other than those illustrated or described here. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or device that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products, or devices.

[0070] In addition, in each embodiment of the present application, each functional unit may be integrated into one processing unit, or each unit may exist physically alone, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of a software functional unit.

[0071] In several embodiments provided in the present application, it should be understood that the disclosed devices and methods may be implemented in other ways. For example, the device embodiments described above are merely illustrative. For example, the above-mentioned division of units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Another point is that the displayed or discussed mutual coupling or direct coupling or communication connection may be through some interfaces. The indirect coupling or communication connection of devices or units may be in electrical, mechanical or other forms.

[0072] The units described above as separate components may or may not be physically separated. The components displayed as units may or may not be physical units, that is, they may be located in one place or distributed to multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0073] In addition, in each embodiment of the present application, each functional unit may be integrated into one processing unit, or each unit may exist physically alone, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of a software functional unit.

[0074] Each embodiment in this specification is described in a progressive manner. The same or similar parts among the embodiments may be referred to each other, and the key point of each embodiment is to illustrate the differences from other embodiments. In particular, for the system embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts may refer to the description of the method embodiment.

[0075] The above describes specific embodiments of this specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims may be performed in a different order than in the embodiments and still achieve the desired result. In addition, the processes depicted in the drawings do not necessarily require the specific order or continuous order shown to achieve the desired result. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0076] The preferred embodiments of the embodiments of the present application have been described above with reference to the accompanying drawings, which do not limit the scope of the rights of the embodiments of the present application. Any modifications, equivalent replacements, and improvements made by those skilled in the art without departing from the scope and essence of the embodiments of the present application shall fall within the scope of the rights of the embodiments of the present application.

Claims

1. An ADC acquisition circuit, characterized in that: The circuit comprises a signal source, a calibration module, an ADC module and a controller, wherein the calibration module is connected to the signal source, the ADC module is connected to the calibration module, and the controller is connected to the calibration module and the ADC module; The signal source is used to output a first test voltage signal and a second test voltage signal in sequence; The calibration module is used to measure a first voltage value corresponding to the first test voltage signal, and to measure a second voltage value corresponding to the second test voltage signal; The ADC module is used to collect the first test voltage signal and the second test voltage signal transmitted by the calibration module to obtain a first value and a second value; The controller is configured to determine a calibration value based on a first difference between the first voltage value and the second voltage value, and a second difference between the first value and the second value; The controller is also used to calibrate the signal value collected by the ADC module according to the calibration value.

2. The ADC acquisition circuit according to claim 1, characterized in that: The circuit also includes a reverse attenuation module connected to the output end of the calibration module and the input end of the ADC module, for scaling down the first test voltage signal and the second test voltage signal, and outputting the scaled-down first test voltage signal and the scaled-down second test voltage signal.

3. The ADC acquisition circuit according to claim 2, characterized in that: The reverse attenuation module includes a first resistor, a second resistor and a first operational amplifier. The first operational amplifier has a first end connected to ground, a second end connected to the first end of the first resistor and the second resistor, and a third end connected to the second end of the second resistor.

4. The ADC acquisition circuit according to claim 3, characterized in that: The circuit also includes a voltage follower module connected to the output end of the reverse attenuation module and the input end of the ADC module, for isolating the reverse attenuation module from the ADC module and transmitting the reduced first test voltage signal and the reduced second test voltage signal to the ADC module.

5. The ADC acquisition circuit according to claim 4, characterized in that: The voltage follower module includes a second operational amplifier, a first terminal of the second operational amplifier is connected to a third terminal, and a second terminal of the second operational amplifier is connected to the third terminal of the first operational amplifier.

6. The ADC acquisition circuit according to claim 1, characterized in that: The circuit also includes a storage module; the controller is also used to store the calibration value in the storage module after determining the calibration value; the controller is also used to retrieve the calibration value from the storage module to calibrate the signal value collected by the ADC module according to the calibration value.

7. The ADC acquisition circuit according to claim 1, characterized in that: The calibration module includes a multimeter for measuring a first voltage value corresponding to the first test voltage signal and a second voltage value corresponding to the second test voltage signal.

8. The ADC acquisition circuit according to claim 1, characterized in that: The calibration value includes a slope value and an offset value and is determined based on the following formula: Among them, K represents the slope value, C represents the offset value, and U a Indicates the first voltage value, U b represents the second voltage value, A represents the first value, and B represents the second value.

9. The ADC acquisition circuit according to claim 8, characterized in that: The signal value collected by the ADC module is calibrated based on the following formula: V = D × K + C; Wherein, V represents the expected output voltage value, D represents the signal value collected by the ADC module, K represents the slope value, and C represents the offset value.

10. An electronic device, characterized in that: The electronic device comprises the ADC acquisition circuit according to any one of claims 1-9.

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