Configurable constant-current constant-voltage power supply system

Abstract

The invention relates to the technical field of power supply management, and discloses a configurable constant-current constant-voltage power supply system. The system comprises a voltage stabilizing unit, a current sampling unit, a voltage sampling unit, an analog-to-digital conversion unit and a processing unit. The current sampling unit converts output current into a voltage signal through a first resistor; the voltage sampling unit converts the output voltage into a collectable voltage signal through a second resistor and a third resistor; the analog-to-digital conversion unit adopts two analog-to-digital converters to respectively acquire voltage signals of the first resistor and the third resistor; the processing unit carries out comparison according to a constant current value or a constant voltage value set by a user and generates a control signal through a processing algorithm, and the output voltage of the voltage stabilizing unit is adjusted through the digital-to-analog converter. A digital control scheme is adopted, a user can flexibly configure a working mode through software, and the device has the advantages of being high in control precision, flexible in parameter configuration and good in stability and is suitable for various application occasions needing precise current or voltage control.

Description

Technical Field

[0001] This application relates to the field of power management, and more particularly to a configurable constant current and constant voltage power supply system. Background Technology

[0002] DC power supplies are crucial devices in applications such as electronic equipment testing, battery charging, and driving specific components. Their core functions typically include two modes: constant voltage output and constant current output. Constant voltage mode requires the power supply to maintain a stable output voltage at a set value when the load changes; this is a fundamental condition for the operation of most circuits. Constant current mode requires the power supply to maintain a stable output current at a set value when the load impedance changes; it is widely used in sensor power supply, battery charging, and semiconductor device testing.

[0003] Traditional DC power supplies often employ analog circuits to achieve constant voltage / constant current control. Typically, two independent analog error amplifiers are designed: one to sample and stabilize the output voltage, and the other to sample and stabilize the output current. The outputs of the two amplifiers are connected via diodes and other components to control a common regulator. In this architecture, whichever output voltage or output current reaches the preset value first, the corresponding loop takes over control. While current analog control schemes offer fast response times, they also have inherent drawbacks: First, the current setpoint is usually changed by adjusting a potentiometer or replacing a resistor, resulting in poor accuracy and flexibility, making control difficult. Second, the temperature drift and aging issues inherent in analog components affect long-term stability and accuracy. Third, their functionality is limited; the switching logic between constant current and constant voltage modes is usually designed in hardware, which is complex and difficult to adjust.

[0004] Therefore, there is an urgent need for a constant current and constant voltage power supply solution with flexible parameter configuration, high stability, and intelligent management, achieving high-precision, high-stability configurable constant current output. Summary of the Invention

[0005] To address the shortcomings of existing technologies and the complexity of regulating current and constant voltage power supplies, this application provides a configurable constant current and constant voltage power supply system, comprising: a voltage regulation unit, including an input terminal, an output terminal, and an adjustment terminal, for dynamically adjusting the output voltage according to the adjustment voltage; a current acquisition unit, including a first resistor connected in series at the output terminal, for converting the output current into a sampleable voltage; a voltage acquisition unit, including a second resistor and a third resistor connected in parallel at the output terminal, for converting the output voltage into a sampleable voltage; an analog-to-digital conversion unit, including a first analog-to-digital converter (ADC) and a second ADC, wherein the first ADC is used to acquire the voltage of the first resistor, and the second ADC is used to acquire the voltage of the third resistor; a processing unit, including a loop filter and a digital-to-analog converter (DAC), wherein the loop filter is connected to the input terminal of the DAC, for receiving the acquired voltages from the first and second ADCs, processing them according to a preset constant voltage or constant current value to generate a control signal, and sending it to the DAC; the output terminal of the DAC is connected to the adjustment terminal of the voltage regulation unit, for converting the control signal into an adjustment voltage, and sending the adjustment voltage to the voltage regulation unit for dynamic adjustment.

[0006] Optionally, in the processing unit, the output voltage and output current of the power supply system are calculated based on the acquisition voltages of the first analog-to-digital converter and the second analog-to-digital converter. The loop filter compares the output voltage or the output current with a preset constant voltage or constant current value to obtain a difference signal, and processes the difference signal to generate the control signal.

[0007] Optionally, the constant voltage and constant current values ​​of the power supply system can be set via software control.

[0008] Optionally, in the current acquisition unit, one end of the first resistor is connected to the output terminal of the voltage regulator unit, and the other end is connected to the output of the power supply system.

[0009] Optionally, in the voltage acquisition unit, the second resistor and the third resistor are connected in series, one end of the second resistor is connected to the output of the power supply system, the other end of the second resistor is connected to one end of the third resistor, and the other end of the third resistor is grounded.

[0010] Optionally, the voltage regulator unit is a linear voltage regulator.

[0011] The beneficial effects of this application are:

[0012] 1. Flexible configuration: The output voltage and output current settings can be controlled and adjusted by the voltage regulator unit. Wide range and high precision output configuration can be achieved without replacing hardware components, which enhances the applicability and automation of the equipment.

[0013] 2. Improve control accuracy by using a high-precision ADC to directly sample the voltage and accurately calculate the real-time current value using a formula. This method avoids the complexity and cost of traditional current detection, while the introduction of digital processing eliminates the inherent temperature drift and aging errors of analog components, resulting in a significant improvement in current control accuracy.

[0014] 3. Enhanced stability: Compared with traditional analog compensation networks, the application of digital loop filters enables more complex and optimized control algorithms, thereby achieving excellent dynamic response performance under various load conditions. Attached Figure Description

[0015] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:

[0016] Figure 1 This is a schematic diagram of a configurable constant current and constant voltage power supply system.

[0017] The above figures include the following reference numerals:

[0018] 1-Three-terminal regulator, 2-First resistor, 3-Second resistor, 4-Third resistor, 5-First ADC (Analog-to-digital converter), 6-Second ADC, 7-Loop filter, 8-DAC (digital-to-analog converter). Detailed Implementation

[0019] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are merely some, not all, of the embodiments of the present application. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without creative effort should fall within the scope of protection of the present application.

[0020] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0021] Figure 1 The diagram shows a configurable constant current and constant voltage power supply system, including a linear regulator. In this embodiment, the linear regulator is specifically a three-terminal regulator 1, without specific limitations. The three-terminal regulator, as a voltage adjustment unit, is used for dynamic adjustment of the output voltage and includes an input terminal, an output terminal, and an adjustment terminal. The current acquisition unit is specifically a first resistor 2, one end of which is connected to the output terminal of the three-terminal regulator, and the other end is output after passing through the first resistor. The resistance value is R1. The voltage acquisition unit specifically includes a voltage divider network composed of a second resistor 3 and a third resistor 4. The voltage acquisition unit is connected in parallel to the output terminal of the regulator, and the second and third resistors are connected in series. One end of the second resistor is connected to the system output, and the other end is connected to the third resistor. The other end of the third resistor is grounded. The resistance values ​​are R2 and R4. 3。

[0022] The system is also equipped with an analog-to-digital conversion unit, including two analog-to-digital converters, which are used to convert the output current and output voltage of the current acquisition unit and the voltage acquisition unit into sampleable voltages. Specifically, it includes a first ADC5 and a second ADC6, wherein the first ADC acquires the output current of the first resistor and converts it into the acquisition voltage V2, and the second ADC acquires the output voltage of the third resistor and converts it into the acquisition voltage V1. In this system, they are specifically ADC1 and ADC2.

[0023] The processing unit includes a loop filter 7 and a DAC 8. In the loop filter, the output current and output voltage are calculated based on the voltage values ​​acquired by ADC1 and ADC2. Then, the required constant current or constant voltage value is preset by the software and compared with the output current and output voltage to obtain a difference signal. This difference signal is processed to generate a control signal, which can specifically increase or decrease the voltage. After the control signal is generated by the loop filter, it is converted into an regulated voltage by the DAC and sent to the regulation terminal of the three-terminal regulator. The three-terminal regulator dynamically adjusts the output voltage according to the regulated voltage, thus forming a closed-loop control to stabilize the output voltage or output current at the set value.

[0024] Among them, the constant current or constant voltage value in the loop filter can be flexibly set by software according to actual needs, so that the system can customize the current and voltage for different application scenarios, realizing high-precision digital power management.

[0025] Specifically, in one embodiment, a constant voltage power supply is regulated, and the voltage divider network is set with the second and third resistors specifically R2 and R3. First, the voltage V1 of R3 is acquired by ADC2, and then the output voltage is calculated by formula (1) of the voltage divider network. :

[0026] (1)

[0027] in, The system's output voltage. R1 represents the voltage across the third resistor, and R2 and R3 represent the resistance values ​​of the second and third resistors, respectively.

[0028] At this point, the system's constant voltage V is preset via software. set The loop filter calculates the difference signal between the constant voltage and the output voltage in real time using formula (2):

[0029] (2)

[0030] in, This is the difference signal between the constant voltage and the output voltage. A pre-set constant voltage.

[0031] When V e When the voltage is >0V, the actual voltage is too low and has not reached the preset voltage value. Therefore, a control signal needs to be sent to increase the output voltage of the three-terminal regulator. e When the voltage is less than 0V, the actual voltage is too high, exceeding the preset voltage value, and a control signal to reduce the output voltage of the three-terminal regulator needs to be sent.

[0032] The current control signal is sent to the DAC, which converts the digital control signal into an analog adjustable voltage to drive the three-terminal regulator. until = At this point, the output voltage reaches the constant voltage value set by the user.

[0033] In another embodiment, constant current power supply regulation is performed by first acquiring voltage V1 through ADC2, and then calculating the system output voltage using formula (1). .

[0034] The ADC1 acquires a voltage of V2, and the output current flows through the first resistor R1 to generate a voltage difference. The voltage drop is calculated according to formula (3):

[0035] (3)

[0036] in, The voltage drop across the first resistor is denoted as . The voltage across the first resistor is denoted as .

[0037] At this point, the output current is calculated according to formula (4):

[0038] (4)

[0039] in, The output current of the power supply system. R1 is the resistance value of the first resistor. In this embodiment, the resistance value of R1 is very small and can be ignored.

[0040] Preset constant current I set The loop filter calculates the difference signal between the constant current and the output current using formula (5):

[0041] (5)

[0042] in, The signal is the difference between the constant current and the output current. A pre-set constant current.

[0043] Difference signal Processed by a loop filter, if When the current is greater than 0, the actual current is less than the set target current, indicating insufficient current. In this case, a control signal to reduce the output voltage of the three-terminal regulator needs to be sent. When the current is less than 0, the actual current is greater than the set target current, and the current exceeds the limit. At this time, it is necessary to send a control signal to increase the output voltage of the three-terminal regulator to limit the current.

[0044] The current control signal is sent to the DAC, which converts the digital control signal into an analog adjustable voltage to drive the regulator to adjust. until = I set At this point, the output current reaches the constant current value set by the user.

[0045] The sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0046] In the above embodiments of this application, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0047] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For instance, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling, direct coupling, or communication connection may be through some interfaces; the indirect coupling or communication connection between units or modules may be electrical or other forms.

[0048] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0049] The above description is only a preferred embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.

Claims

1. A configurable constant current and constant voltage power supply system, characterized in that, include: The voltage regulator unit includes an input terminal, an output terminal, and an adjustment terminal, and is used to dynamically adjust the output voltage according to the adjustment voltage; The current acquisition unit includes a first resistor connected in series at the output terminal, used to convert the output current into a sampleable voltage; A voltage acquisition unit includes a second resistor and a third resistor connected in parallel at the output terminal, used to convert the output voltage into a sampleable voltage; An analog-to-digital conversion unit includes a first analog-to-digital converter and a second analog-to-digital converter. The first analog-to-digital converter is used to acquire the voltage of the first resistor, and the second analog-to-digital converter is used to acquire the voltage of the third resistor. The processing unit includes a loop filter and a digital-to-analog converter. The loop filter is connected to the input terminal of the digital-to-analog converter and is used to receive the sampled voltages from the first analog-to-digital converter and the second analog-to-digital converter, and process them according to a preset constant voltage value or constant current value to generate a control signal, which is then sent to the digital-to-analog converter. The output terminal of the digital-to-analog converter is connected to the adjustment terminal of the voltage regulator unit, and is used to convert the control signal into an adjustable voltage and send the adjustable voltage to the voltage regulator unit for dynamic adjustment.

2. The configurable constant current and constant voltage power supply system according to claim 1, characterized in that, In the processing unit, the output voltage and output current of the power supply system are calculated based on the voltages collected by the first analog-to-digital converter and the second analog-to-digital converter. The loop filter compares the output voltage or the output current with a preset constant voltage or constant current value to obtain a difference signal, and processes the difference signal to generate the control signal.

3. A configurable constant current and constant voltage power supply system according to claim 1, characterized in that, The constant voltage and constant current values ​​of the power system are set via software control.

4. A configurable constant current and constant voltage power supply system according to claim 1, characterized in that, In the current acquisition unit, one end of the first resistor is connected to the output terminal of the voltage regulator unit, and the other end is connected to the output of the power supply system.

5. A configurable constant current and constant voltage power supply system according to claim 1, characterized in that, In the voltage acquisition unit, the second resistor and the third resistor are connected in series. One end of the second resistor is connected to the output of the power supply system, and the other end of the second resistor is connected to one end of the third resistor. The other end of the third resistor is grounded.

6. A configurable constant current and constant voltage power supply system according to claim 1, characterized in that, The voltage regulator unit is a linear voltage regulator.

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