Internal self-calibration system of digital regulated power supply and control method thereof

Abstract

The application discloses an internal self-calibration system of a digital stabilized power supply and a control method thereof. The system comprises a stabilized power supply main circuit module, which is used for sending preset calibration parameters to a high-precision resistor module; the high-precision resistor module is used for receiving the preset calibration parameters, matching calibration data according to the preset calibration parameters, and sending the calibration data to the stabilized power supply main circuit module; the stabilized power supply main circuit module is also used for receiving the calibration data, calculating a calibration deviation according to the calibration data, and calibrating the stabilized power supply according to the calibration deviation; and a bidirectional communication module is used for providing communication interaction for the high-precision resistor module and the stabilized power supply main circuit module to realize data interaction. Before an external load is connected, fast, automatic and high-precision internal self-calibration can be realized, so that the stabilized power supply can provide stable and accurate output from power-on, and therefore the reliability and user experience of the power supply are improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of power supply calibration, in particular to an internal self-calibration system of a digital regulated power supply and a control method thereof. BACKGROUND

[0002] The output precision of a digital regulated power supply is crucial for the operation of electronic devices, and calibration is a key link to ensure its precision. Early calibration relies on external high-precision instruments, which can achieve high precision, but has limitations such as expensive external instruments, complex operation, the need for professional personnel, high calibration cost, and difficulty in maintaining factory calibration precision due to component aging, making frequent external calibration unrealistic.

[0003] Therefore, some digital regulated power supplies with internal self-calibration or adaptive adjustment functions have appeared in the prior art. A common solution is to sample the output voltage and current values after connecting an external load, compare them with the internal set target value, and adjust the output in real time by a microcontroller (MCU). However, this solution that relies on external actual working load has many defects: (1) Since the impedance characteristics of external loads are complex and variable, sampling and adjustment based on this may not be accurate or may produce oscillation, and the precision is sensitive to specific load conditions, so the calibration precision is greatly affected by the characteristics of external loads, and the universality is poor; (2) The output accuracy is not guaranteed during the initial startup of the power supply or when the load is connected but the calibration is not completed, which may cause device abnormalities or damage, so it cannot guarantee the output precision before actual power supply, and there is a risk for sensitive loads; (3) The calibration process may be tedious, and users may need to perform specific operations, and the operation steps are complex when multiple points are calibrated, making it difficult to fully automate; (4) Sampling, calculation, and adjustment based on external loads require a certain amount of time, resulting in a significant delay from startup to stable and accurate output, affecting response capability and user experience.

[0004] Therefore, the solution in the prior art that relies on external working load for internal self-calibration cannot fundamentally solve the precision and convenience problems encountered by digital regulated power supplies in actual application. SUMMARY

[0005] The present application provides an internal self-calibration system of a digital regulated power supply and a control method thereof, which can achieve fast, automatic, and high-precision internal self-calibration without relying on external actual working load or before connecting an external load, to ensure that the power supply can provide stable and accurate output from the moment it is powered on, and fundamentally improve the reliability and user experience of the power supply.

[0006] To achieve the above purpose, the embodiments of the present application provide an internal self-calibration system of a digital regulated power supply, comprising:

[0007] a regulated power supply main circuit module, a high-precision resistor module, and a bidirectional communication module;

[0008] The voltage regulator main circuit module is configured to send preset calibration parameters to the high-precision resistor module.

[0009] The high-precision resistor module is configured to receive the preset calibration parameters, match calibration data according to the preset calibration parameters, and send the calibration data to the voltage regulator main circuit module.

[0010] The voltage regulator main circuit module is further configured to receive the calibration data, calculate a calibration deviation according to the calibration data, and calibrate the voltage regulator according to the calibration deviation.

[0011] The bidirectional communication module is configured to provide communication interaction between the high-precision resistor module and the voltage regulator main circuit module for data interaction.

[0012] As an improvement of the above-mentioned scheme, the high-precision resistor module comprises:

[0013] a high-precision fixed resistance value calibration load, an electronic switch circuit, and a sampling circuit.

[0014] The high-precision fixed resistance value calibration load is configured to provide a stable reference calibration load for the voltage regulator.

[0015] The electronic switch circuit is configured to control the connection state of the high-precision fixed resistance value calibration load and the power output loop.

[0016] The sampling circuit is configured to measure the current and voltage of the high-precision fixed resistance value calibration load according to the preset calibration parameters, and obtain calibration data according to the current and voltage.

[0017] As an improvement of the above-mentioned scheme, if the internal self-calibration system further comprises a PWM signal control circuit.

[0018] The voltage regulator main circuit module is further configured to generate a control instruction according to the calibration deviation, and send the control instruction to the PWM signal control circuit.

[0019] The PWM signal control circuit is configured to receive the control instruction, generate an adjusted PWM signal according to the control instruction, and calibrate the voltage regulator.

[0020] As an improvement of the above-mentioned scheme, the sampling circuit comprises:

[0021] a signal acquisition circuit, a load control circuit, and a voltage dividing circuit.

[0022] The signal acquisition circuit comprises an analog-to-digital converter, a first resistor, a second resistor, a first capacitor, and a first electrolytic capacitor.

[0023] The voltage dividing circuit comprises a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor and an eighth resistor;

[0024] The load control circuit comprises a first relay, a first diode, a second diode, a second switch tube and a thirteenth resistor;

[0025] The 1 pin of the analog-to-digital converter is connected to the first end of the seventh resistor, the 2 pin and the 6 pin of the analog-to-digital converter are grounded, the 3 pin of the analog-to-digital converter is connected to the first end of the first resistor, and the analog-to-digital converter is connected to the voltage stabilizing power supply main circuit module through a bus I2C2, the 4 pin of the analog-to-digital converter is connected to the first end of the second resistor, and the analog-to-digital converter is connected to the voltage stabilizing power supply main circuit module through the bus I2C2, the 5 pin of the analog-to-digital converter is connected to a 5V power supply, the second end of the first resistor is connected to the 5V power supply, the first end of the first capacitor is connected to the 5V power supply, the second end of the first capacitor is grounded, the first end of the first electrolytic capacitor is connected to the 5V power supply, and the second end of the first electrolytic capacitor is grounded;

[0026] The first end of the seventh resistor is connected to the first end of the sixth resistor, and the second end of the seventh resistor is grounded; the second end of the sixth resistor is connected to the first end of the fifth resistor, the second end of the fifth resistor is connected to the first end of the fourth resistor and the eighth resistor, the second end of the fourth resistor is connected to a power supply red terminal and the third end of the first relay, and the second end of the eighth resistor is grounded;

[0027] The first end of the first relay is connected to the first end of the first diode and the second diode, the second end of the first diode is connected to a 12V power supply, the second end of the second diode is connected to the second end of the first relay and the collector of the second switch tube, the emitter of the second switch tube is grounded, the base of the second switch tube is connected to the first end of the thirteenth resistor, and the second end of the thirteenth resistor is connected to a control load.

[0028] As an improvement of the above scheme, the sampling circuit comprises:

[0029] A signal acquisition filtering circuit, a signal amplification circuit and an ADC acquisition circuit;

[0030] The signal acquisition filtering circuit comprises a sampling resistor, a seventeenth resistor, a twenty-second resistor, an eighth capacitor, a twelfth capacitor, an eighteenth resistor and a twenty-third resistor;

[0031] The signal amplification circuit comprises an operational amplifier, a sixteenth resistor, a first adjustable resistor, a twenty-fourth resistor, a fourth capacitor, a sixth capacitor, a tenth capacitor and a thirteenth capacitor;

[0032] The ADC acquisition circuit includes an analog-to-digital converter, a fourteenth resistor, a fifteenth resistor, a fifth capacitor, and a seventh electrolytic capacitor.

[0033] The sampling resistor has one end connected to one end of the twenty-second resistor and grounded, and the other end connected to one end of the seventeenth resistor. The other end of the twenty-second resistor is connected to one end of the twenty-third resistor and one end of the twelfth capacitor, and the other end of the twelfth capacitor is grounded. The other end of the twenty-third resistor is connected to the second interface of the operational amplifier, one end of the thirteenth capacitor, and one end of the twenty-fourth resistor. The other end of the seventeenth resistor is connected to one end of the eighth capacitor and one end of the eighteenth resistor, and the other end of the eighth capacitor is grounded. The other end of the eighteenth resistor is connected to the sixteenth resistor and one end of the sixth capacitor, and the third interface of the operational amplifier.

[0034] The first and eighth interfaces of the operational amplifier are respectively connected to the third and first ends of the first adjustable resistor. The seventh and fourth interfaces of the operational amplifier are respectively connected to positive and negative 5V power supplies. The sixth interface of the operational amplifier is connected to the other ends of the thirteenth capacitor and the twenty-fourth resistor, and the first pin of the analog-to-digital converter. One end of the tenth capacitor is connected to a negative 5V power supply, and the other end is grounded. One end of the fourth capacitor is connected to a positive 5V power supply, and the other end is grounded. The second end of the first adjustable resistor is connected to a positive 5V power supply. The other ends of the sixteenth resistor and the sixth capacitor are grounded.

[0035] The second and sixth pins of the analog-to-digital converter are grounded. The third and fourth pins of the analog-to-digital converter are respectively connected to one end of the fourteenth resistor and one end of the fifteenth resistor, and connected to the voltage regulator main circuit module through the bus I2C1. The fifth pin of the analog-to-digital converter is connected to a 5V power supply. The other ends of the fourteenth resistor and the fifteenth resistor are connected to a 5V power supply. One end of the fifth capacitor and the seventh electrolytic capacitor is connected to a 5V power supply, and the other end is grounded.

[0036] As an improvement of the above scheme, the voltage regulator main circuit module includes:

[0037] A power conversion circuit and a control circuit.

[0038] The control circuit includes a controller, a power filter circuit, and a pin interface.

[0039] The power filter circuit includes a seventh capacitor, a ninth capacitor, an eleventh capacitor, a fourteenth capacitor, a nineteenth resistor, and a twentieth resistor.

[0040] The first to fourth interfaces of the pin interface are respectively connected to the fourteenth to seventeenth pins of the controller.

[0041] One end of the seventh capacitor is connected to the 48th pin of the controller, and the other end is grounded; one end of the ninth capacitor is connected to the 7th pin of the controller, and the other end is grounded; one end of the eleventh capacitor is connected to the 9th pin of the controller, and the other end is grounded; one end of the fourteenth capacitor is connected to the 24th pin of the controller, and the other end is grounded; one end of the nineteenth resistor is connected to the 44th pin of the controller, and the other end is grounded; one end of the twentieth resistor is connected to a 3.3V power supply, and the other end is connected to the ninth capacitor.

[0042] As an improvement of the above scheme, the power conversion circuit comprises:

[0043] a rectifier filter circuit, a step-down voltage stabilizing circuit and a protection circuit;

[0044] The rectifier filter circuit comprises an input interface, a first rectifier bridge and a fifth electrolytic capacitor;

[0045] The step-down voltage stabilizing circuit comprises a second linear voltage stabilizer, a third linear voltage stabilizer, a second capacitor, a sixth electrolytic capacitor, a third capacitor, a fourth electrolytic capacitor, a ninth resistor and a tenth resistor;

[0046] The protection circuit comprises a first voltage stabilizing diode, a third resistor, a second electrolytic capacitor and a third electrolytic capacitor;

[0047] The first interface and the third interface of the input interface are respectively connected to the third end and the second end of the first rectifier bridge, the second interface of the input interface is grounded, the first end of the first rectifier bridge is connected to a 12V power supply, the fourth end of the first rectifier bridge is connected to one end of the third resistor and the second electrolytic capacitor, one end of the fifth electrolytic capacitor is connected to a 12V power supply, and the other end is grounded;

[0048] The first end of the second linear voltage stabilizer is grounded, the third end of the second linear voltage stabilizer is connected to a 5V power supply, the second end and the fourth end of the second linear voltage stabilizer are connected to a 3.3V power supply, one end of the third capacitor and the fourth electrolytic capacitor is connected to a 3.3V power supply, and the other end is grounded, one end of the ninth resistor is connected to a 3.3V power supply, and the other end is connected to an alternating current 3.3V power supply, one end of the tenth resistor is connected to the third capacitor, and the other end is connected to an alternating current ground; the first end of the third linear voltage stabilizer is connected to a 12V power supply, the second end of the third linear voltage stabilizer is grounded, the third end of the third linear voltage stabilizer is connected to a 5V power supply, one end of the second capacitor and the sixth electrolytic capacitor is connected to a 5V power supply, and the other end is grounded;

[0049] The other end of the third resistor is connected to a negative 5V power supply, the other end of the second electrolytic capacitor is grounded, one end of the first voltage stabilizing diode and the third electrolytic capacitor is connected to a negative 5V power supply, and the other end is grounded.

[0050] As an improvement of the above-mentioned scheme, the controller is a single-chip microcomputer.

[0051] As an improvement of the above-mentioned scheme, the bidirectional communication module realizes bidirectional communication interaction through an I2C bus.

[0052] In order to achieve the above-mentioned purpose, the embodiment of the present application provides an internal self-calibration system control method of a digital voltage stabilizing power supply, comprising:

[0053] When receiving a self-calibration trigger instruction, the voltage stabilizing power supply main circuit module sends preset calibration parameters to the high-precision resistor module through the bidirectional communication module;

[0054] The high-precision resistor module receives the preset calibration parameters, matches calibration data according to the preset calibration parameters, and sends the calibration data to the voltage stabilizing power supply main circuit module through the bidirectional communication module;

[0055] The voltage stabilizing power supply main circuit module receives the calibration data, calculates a calibration deviation according to the calibration data, and calibrates the voltage stabilizing power supply according to the calibration deviation.

[0056] Compared with the prior art, the embodiment of the present application discloses an internal self-calibration system of a digital voltage stabilizing power supply and a control method thereof, the system comprising a voltage stabilizing power supply main circuit module, a high-precision resistor module and a bidirectional communication module; the voltage stabilizing power supply main circuit module is used for sending preset calibration parameters to the high-precision resistor module; the high-precision resistor module is used for receiving the preset calibration parameters, matching calibration data according to the preset calibration parameters, and sending the calibration data to the voltage stabilizing power supply main circuit module; the voltage stabilizing power supply main circuit module is also used for receiving the calibration data, calculating a calibration deviation according to the calibration data, and calibrating the voltage stabilizing power supply according to the calibration deviation; and the bidirectional communication module is used for providing communication interaction for the high-precision resistor module and the voltage stabilizing power supply main circuit module to realize data interaction. Without relying on external actual working load or before connecting an external load, fast, automatic and high-precision internal self-calibration can be realized to ensure that the power supply can provide stable and accurate output from power-on, and the reliability and user experience of the power supply are fundamentally improved. BRIEF DESCRIPTION OF DRAWINGS

[0057] Figure 1 is a structural schematic diagram of an internal self-calibration system of a digital voltage stabilizing power supply provided by the embodiment of the present application;

[0058] Figure 2 is a schematic diagram of a sampling circuit provided by the embodiment of the present application;

[0059] Figure 3is another sampling circuit schematic diagram provided by the embodiment of the present application;

[0060] Figure 4 is a control circuit schematic diagram provided by the embodiment of the present application;

[0061] Figure 5 is a power conversion circuit schematic diagram provided by the embodiment of the present application;

[0062] Figure 6 is a flow diagram of an internal self-calibration system control method of a digital regulated power supply provided by the embodiment of the present application. DETAILED DESCRIPTION

[0063] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0064] It should be noted that the terms "comprise" and "specific" and any variations of them in the present application are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device comprising a series of steps or units does not have to be limited to the clearly listed steps or units, but can include other steps or units that are not clearly listed or inherent to the process, method, product or device.

[0065] Please refer to Figure 1 , Figure 1 is a structure diagram of an internal self-calibration system of a digital regulated power supply provided by the embodiment of the present application, and the internal self-calibration system of the digital regulated power supply comprises:

[0066] a regulated power supply main circuit module, a high-precision resistor module and a bidirectional communication module;

[0067] The regulated power supply main circuit module is configured to send preset calibration parameters to the high-precision resistor module.

[0068] The high-precision resistor module is configured to receive the preset calibration parameters, match calibration data according to the preset calibration parameters, and send the calibration data to the regulated power supply main circuit module.

[0069] The regulated power supply main circuit module is further configured to receive the calibration data, calculate a calibration deviation according to the calibration data, and calibrate the regulated power supply according to the calibration deviation.

[0070] The bidirectional communication module is used for providing communication interaction for the high-precision resistor module and the voltage stabilizing power supply main circuit module to perform data interaction.

[0071] For example, after the power supply of the internal self-calibration system of the digital voltage stabilizing power supply is powered on or a specific trigger condition (such as a user manually triggering a calibration instruction) is met, the system first performs a short time delay to ensure that the power supply main circuit is preliminarily stable. The voltage stabilizing power supply main circuit module, as a control core, starts to initialize self-calibration related modules, including a high-precision resistor module (containing a high-precision resistor, an intelligent switch, an AD sampling circuit, etc.) and a bidirectional communication module. The voltage stabilizing power supply main circuit module drives the electronic switch circuit in the high-precision resistor module to be closed through a control signal (such as an I2C bus instruction or directly controlling a relay switch), temporarily connects the built-in high-precision fixed resistance calibration load to the power supply output loop, and replaces the external uncertain load with the high-precision fixed resistance calibration load as a reference load with a known resistance to provide a stable electrical environment for calibration. The voltage stabilizing power supply main circuit module sends preset calibration parameters (including a target voltage and a current set point, such as a 1V or 5V voltage point that needs to be calibrated) to the high-precision resistor module. The high-precision resistor module receives the preset calibration parameters through the bidirectional communication module between the high-precision resistor module and the voltage stabilizing power supply main circuit module, automatically matches internal calibration data (such as a standard current value corresponding to the target voltage) according to the preset calibration parameters, realizes an automatic tracking function, and sends the calibration data to the voltage stabilizing power supply main circuit module. The voltage stabilizing power supply main circuit module receives the calibration data, calculates a calibration deviation according to the calibration data and an internally preset reference value, and calibrates the voltage stabilizing power supply according to the calibration deviation. When the voltage stabilizing power supply main circuit module determines that the calibration parameters meet the standard, the voltage stabilizing power supply main circuit module immediately drives the intelligent electronic switch to be disconnected through a control signal to isolate the high-precision resistor module from the power supply output end, thereby avoiding interference of the calibration load on subsequent external load connection or normal power supply output. After the calibration process is completed, the power supply enters a normal working mode to output a voltage or a current that has been accurately calibrated and can be directly connected to an external load.

[0072] The embodiment of the present application integrates a high-precision fixed calibration load with a known resistance, a controlled electronic switch, a sampling circuit and a bidirectional communication module between the voltage stabilizing power supply main circuit module in a digital voltage stabilizing power supply to construct a system that can independently calibrate an internal self-calibration system from an external actual working load, quickly and automatically calibrate the internal self-calibration system at the initial stage of power supply startup or at a specific time, solve the problems of limited precision, poor universality and inability to guarantee output precision before actual power supply in the prior art, and solve the problems of a complicated calibration process, a need for external instruments or specific operations and a delay in output stabilization in the prior art.

[0073] Specifically, the high-precision resistor module includes:

[0074] high-precision fixed resistance calibration load, electronic switch circuit and sampling circuit;

[0075] The high-precision fixed resistance calibration load is used to provide a stable reference calibration load for the voltage stabilizing power supply.

[0076] The electronic switch circuit is used to control the connection state of the high-precision fixed resistance calibration load and the power output loop.

[0077] The sampling circuit is used to measure the current and voltage of the high-precision fixed resistance calibration load according to the preset calibration parameters, and obtain calibration data according to the current and voltage.

[0078] For example, the high-precision fixed resistance calibration load is an internal high-precision alloy resistor, which is the core resistor part of the high-precision resistor module. The resistance value is pre-selected according to the output voltage range of the power supply, serving as a reference calibration load. The electronic switch circuit is integrated in the high-precision resistor module or controlled by the voltage stabilizing power supply main circuit module through a control signal (such as indirectly controlling the internal switch of the high-precision resistor module through an I2C bus, or directly controlling an external relay / switch to connect or disconnect the calibration resistor to the output loop) to temporarily connect the high-precision fixed resistance calibration load in series or parallel to the power output end during the calibration stage, and automatically disconnect after calibration. The sampling circuit is integrated in the high-precision resistor module, which is used to accurately measure the current flowing through the load (by measuring the voltage across it or cooperating with a precision sampling resistor in series) and / or the voltage across it when the rated voltage is applied to the high-precision fixed resistance calibration load.

[0079] Further, if the internal self-calibration system further comprises a PWM signal control circuit;

[0080] The voltage stabilizing power supply main circuit module is further used to generate a control instruction according to the calibration deviation, and send the control instruction to the PWM signal control circuit.

[0081] The PWM signal control circuit is used to receive the control instruction and generate an adjusted PWM signal according to the control instruction to calibrate the voltage stabilizing power supply.

[0082] For example, after the calibration load is connected, the MCU of the main circuit module of the stabilized power supply outputs a preset calibration voltage (such as a rated voltage) to both ends of the high-precision resistor, the sampling circuit starts to work, the current flowing through the high-precision resistor (calculated by measuring the voltage across the resistor combined with the resistance value, or cooperating with a series sampling resistor) and / or the voltage across the resistor is accurately measured, and the measurement result is converted into an AD value; the sampling circuit feeds back the AD value to the MCU in real time through bidirectional communication as original data for calibration adjustment; the MCU compares the received AD value with an internally preset reference value (corresponding to the theoretical value of the target voltage / current) and calculates the output deviation (such as the difference between the actual voltage and the target voltage). According to the deviation result, the MCU generates an adjustment PWM signal through the PWM signal control circuit to accurately change the pulse width (duty ratio) and then control the output of the main power conversion stage of the power supply, so as to gradually reduce the deviation between the actual output and the target value. The closed-loop process of “sampling-feedback-computation-adjustment” is repeated until the AD sampling value converges within the preset accuracy range (i.e. the deviation between the actual output and the target value is less than the allowable error), and the calibration is completed by disconnecting the calibration load. PWM signal control circuit: the MCU compares and calculates the read AD value with the preset reference value, and adjusts the PWM (pulse width modulation) signal (which finally affects the output of the main power conversion stage of the power supply) to accurately calibrate the output voltage / current of the power supply.

[0083] It is worth noting that if multi-point calibration is required (such as calibration at different voltage / current output points to improve the accuracy of the entire range), the MCU will automatically switch to the next target parameter (such as from 5V to 10V) and repeat the above self-calibration process: re-send the preset calibration parameters to the high-precision resistor module, sample the AD value under the new parameters, adjust the PWM until the standard is met, and finally complete the calibration of the entire range. Since the high-precision resistor module has an automatic tracking function, multi-point calibration does not require manual operation of external loads or frequent parameter setting, and the entire process is automatically completed by the MCU and the high-precision resistor module.

[0084] More specifically, the sampling circuit comprises:

[0085] a signal acquisition circuit, a load control circuit and a voltage dividing circuit;

[0086] The signal acquisition circuit comprises an analog-to-digital converter, a first resistor, a second resistor, a first capacitor and a first electrolytic capacitor.

[0087] The voltage dividing circuit comprises a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor and an eighth resistor.

[0088] The load control circuit comprises a first relay, a first diode, a second diode, a second switch tube and a thirteenth resistor.

[0089] The first pin of the analog-to-digital converter is connected to the first end of the seventh resistor, the 2 pin and the 6 pin of the analog-to-digital converter are grounded, the 3 pin of the analog-to-digital converter is connected to the first end of the first resistor, and is connected with the voltage stabilizing power supply main circuit module through the bus I2C2, the 4 pin of the analog-to-digital converter is connected to the first end of the second resistor, and is connected with the voltage stabilizing power supply main circuit module through the bus I2C2, the 5 pin of the analog-to-digital converter is connected to a 5V power supply, the second end of the first resistor is connected to the 5V power supply, the first end of the first capacitor is connected to the 5V power supply, the second end of the first capacitor is grounded, the first end of the first electrolytic capacitor is connected to the 5V power supply, and the second end of the first electrolytic capacitor is grounded.

[0090] The first end of the seventh resistor is connected to the first end of the sixth resistor, and the second end of the seventh resistor is grounded; the second end of the sixth resistor is connected to the first end of the fifth resistor, the second end of the fifth resistor is connected to the first end of the fourth resistor and the eighth resistor, the second end of the fourth resistor is connected to a power supply red terminal and the third end of the first relay, and the second end of the eighth resistor is grounded.

[0091] The first end of the first relay is connected to the first end of the first diode and the second diode, the second end of the first diode is connected to a 12V power supply, the second end of the second diode is connected to the second end of the first relay and the collector of the second switch tube, the emitter of the second switch tube is grounded, the base of the second switch tube is connected to the first end of the thirteenth resistor, and the second end of the thirteenth resistor is connected to a control load.

[0092] As shown in Figure 2 , Figure 2 is a sampling circuit schematic diagram provided by an embodiment of the application, the sampling circuit comprises a signal acquisition circuit, a load control circuit and a voltage dividing circuit. Figure 2 The signal acquisition circuit comprises an analog-to-digital converter U1, a first resistor R1, a second resistor R2, a first capacitor C1 and a first electrolytic capacitor E1; the voltage dividing circuit comprises a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7 and an eighth resistor R8; and the load control circuit comprises a first relay JK1, a first diode D1, a second diode D2, a second switch tube Q2 and a thirteenth resistor R13.

[0093] The first pin of the analog-to-digital converter U1 is connected to the first end of the seventh resistor R7, the 2 pin and the 6 pin of the analog-to-digital converter U1 are grounded, the 3 pin of the analog-to-digital converter U1 is connected to the first end of the first resistor R1, and is connected to the voltage stabilizing power supply main circuit module through the bus I2C2, the 4 pin of the analog-to-digital converter U1 is connected to the first end of the second resistor R2, and is connected to the voltage stabilizing power supply main circuit module through the bus I2C2, the 5 pin of the analog-to-digital converter U1 is connected to a 5V power supply, the second end of the first resistor R1 is connected to the 5V power supply, the first end of the first capacitor C1 is connected to the 5V power supply, the second end of the first capacitor C1 is grounded, the first end of the first electrolytic capacitor E1 is connected to the 5V power supply, and the second end of the first electrolytic capacitor E1 is grounded;

[0094] The first end of the seventh resistor R7 is connected to the first end of the sixth resistor R6, and the second end of the seventh resistor R7 is grounded; the second end of the sixth resistor R6 is connected to the first end of the fifth resistor R5, the second end of the fifth resistor R5 is connected to the first end of the fourth resistor R4 and the eighth resistor R8, the second end of the fourth resistor R4 is connected to the power supply red terminal and the third end of the first relay JK1, and the second end of the eighth resistor R8 is grounded;

[0095] The first end of the first relay JK1 is connected to the first end of the first diode D1 and the second diode D2, the second end of the first diode D1 is connected to a 12V power supply, the second end of the second diode D2 is connected to the second end of the first relay JK1 and the collector of the second switch tube Q2, the emitter of the second switch tube Q2 is grounded, and the base of the second switch tube Q2 is connected to the first end of the thirteenth resistor R13, and the second end of the thirteenth resistor R13 is connected to control the load.

[0096] It can be understood that the signal acquisition circuit converts the analog voltage signal into a digital quantity and outputs it through the I2C bus (I2C2_SCL / I2C2_SDA); the first relay in the load control circuit serves as an execution element for controlling the on-off of the load. When the relay coil is powered, the contact is closed, connecting the load yellow terminal (P2) and the external load, so that the load is powered on and works; when the relay coil is powered off, the contact is opened, and the load stops working; the voltage signal input by the power supply red terminal (P1) is processed by the voltage dividing circuit, so that the voltage input to the Vin + pin of the MCP3425 chip is within the processable range.

[0097] More specifically, the sampling circuit comprises:

[0098] The signal acquisition filtering circuit, the signal amplification circuit and the ADC acquisition circuit;

[0099] The signal acquisition filtering circuit comprises a sampling resistor, a seventeenth resistor, a twenty-second resistor, an eighth capacitor, a twelfth capacitor, an eighteenth resistor and a twenty-third resistor.

[0100] The signal amplification circuit comprises an operational amplifier, a sixteenth resistor, a first adjustable resistor, a twenty-fourth resistor, a fourth capacitor, a sixth capacitor, a tenth capacitor and a thirteenth capacitor;

[0101] The ADC acquisition circuit comprises an analog-digital converter, a fourteenth resistor, a fifteenth resistor, a fifth capacitor and a seventh electrolytic capacitor;

[0102] One end of the sampling resistor is connected to one end of the twenty-second resistor and the ground, the other end of the sampling resistor is connected to one end of the seventeenth resistor, one end of the twenty-second resistor is connected to one end of the twenty-third resistor and one end of the twelfth capacitor, the other end of the twelfth capacitor is connected to the ground, the other end of the twenty-third resistor is connected to the second interface of the operational amplifier, one end of the thirteenth capacitor and one end of the twenty-fourth resistor, the other end of the seventeenth resistor is connected to one end of the eighth capacitor and one end of the eighteenth resistor, the other end of the eighth capacitor is connected to the ground, and the other end of the eighteenth resistor is connected to one end of the sixteenth resistor and the sixth capacitor and the third interface of the operational amplifier;

[0103] The first interface and the eighth interface of the operational amplifier are respectively connected to the third end and the first end of the first adjustable resistor, the seventh interface and the fourth interface of the operational amplifier are respectively connected to positive and negative 5V power supplies, the sixth interface of the operational amplifier is connected to the other end of the thirteenth capacitor and the twenty-fourth resistor and the first pin of the analog-digital converter, one end of the tenth capacitor is connected to a negative 5V power supply and the other end is connected to the ground, one end of the fourth capacitor is connected to a positive 5V power supply and the other end is connected to the ground, the second end of the first adjustable resistor is connected to a positive 5V power supply, and the other end of the sixteenth resistor and the sixth capacitor is connected to the ground;

[0104] The second pin and the sixth pin of the analog-digital converter are connected to the ground, the third pin and the fourth pin of the analog-digital converter are respectively connected to one end of the fourteenth resistor and the fifteenth resistor, and are connected to the voltage stabilizing power supply main circuit module through a bus I2C1, the fifth pin of the analog-digital converter is connected to a 5V power supply, the other end of the fourteenth resistor and the fifteenth resistor is connected to a 5V power supply, and one end of the fifth capacitor and the seventh electrolytic capacitor is connected to a 5V power supply and the other end is connected to the ground.

[0105] As shown in Figure 3 , Figure 3 is another sampling circuit schematic diagram provided by the embodiment of the application, and the signal acquisition filtering circuit, the signal amplification circuit and the ADC acquisition circuit; Figure 3In the specific embodiment, the signal acquisition filter circuit comprises a sampling resistor R21, a seventeenth resistor R17, a twenty-second resistor R22, an eighth capacitor C8, a twelfth capacitor C12, an eighteenth resistor R18, and a twenty-third resistor R23; the signal amplification circuit comprises an operational amplifier U7, a sixteenth resistor R16, a first adjustable resistor VR1, a twenty-fourth resistor R24, a fourth capacitor C4, a sixth capacitor C6, a tenth capacitor C10, and a thirteenth capacitor C13; and the ADC acquisition circuit comprises an analog-to-digital converter U6, a fourteenth resistor R14, a fifteenth resistor R15, a fifth capacitor C5, and a seventh electrolytic capacitor E7.

[0106] One end of the sampling resistor R21 is connected to one end of the twenty-second resistor R22 and to the ground, the other end of the sampling resistor R21 is connected to one end of the seventeenth resistor R17, one end of the twenty-second resistor R22 is connected to one end of the twelfth capacitor C12 and one end of the twenty-third resistor R23, the other end of the twelfth capacitor C12 is connected to the ground, the other end of the twenty-third resistor R23 is connected to the second interface of the operational amplifier U7, one end of the thirteenth capacitor C13, and one end of the twenty-fourth resistor R24, the other end of the seventeenth resistor R17 is connected to one end of the eighth capacitor C8 and one end of the eighteenth resistor R18, the other end of the eighth capacitor C8 is connected to the ground, and the other end of the eighteenth resistor R18 is connected to the sixteenth resistor R16, one end of the sixth capacitor C6, and the third interface of the operational amplifier U7.

[0107] The first interface and the eighth interface of the operational amplifier U7 are respectively connected to the third end and the first end of the first adjustable resistor VR1, the seventh interface and the fourth interface of the operational amplifier U7 are respectively connected to the positive and negative 5V power supply, the sixth interface of the operational amplifier U7 is connected to the other end of the thirteenth capacitor C13 and the twenty-fourth resistor R24, and the first pin of the analog-to-digital converter U6, one end of the tenth capacitor C10 is connected to the negative 5V power supply, and the other end is connected to the ground, one end of the fourth capacitor C4 is connected to the positive 5V power supply, and the other end is connected to the ground, the second end of the first adjustable resistor VR1 is connected to the positive 5V power supply, and the other end of the sixteenth resistor R16 and the sixth capacitor C6 is connected to the ground.

[0108] The second pin and the sixth pin of the analog-to-digital converter U6 are connected to the ground, the third pin and the fourth pin of the analog-to-digital converter U6 are respectively connected to one end of the fourteenth resistor R14 and the fifteenth resistor R15, and are connected to the voltage stabilizing power supply main circuit module through the bus I2C1, the fifth pin of the analog-to-digital converter U6 is connected to the 5V power supply, the other end of the fourteenth resistor R14 and the fifteenth resistor R15 is connected to the 5V power supply, one end of the fifth capacitor C5 and the seventh electrolytic capacitor E7 is connected to the 5V power supply, and the other end is connected to the ground.

[0109] Understandably, the signal acquisition and filtering circuit utilizes sampling resistor R21. When load current flows from P3 (black terminal load) through R21, according to Ohm's law, the larger the current, the larger the voltage difference across R21. By detecting this voltage difference, the load current is indirectly measured. The voltage signal across R21 is then subjected to RC filtering to remove high-frequency noise (such as load current fluctuations and electromagnetic interference), ensuring the purity of the signal input to the operational amplifier. The signal amplification circuit amplifies the small voltage to a range suitable for ADC acquisition. C4 and C10 are used for filtering and removing power supply noise, and AGND is analog ground to ensure signal purity. The ADC acquisition circuit converts the amplified voltage signal into a digital voltage signal and outputs it via the I2C bus.

[0110] Specifically, the main circuit module of the regulated power supply includes:

[0111] Power conversion circuit and control circuit;

[0112] The control circuit includes a controller, a power filter circuit, and a pin header interface;

[0113] The power supply filtering circuit includes a seventh capacitor, a ninth capacitor, an eleventh capacitor, a fourteenth capacitor, a nineteenth resistor, and a twentieth resistor.

[0114] The first to fourth pin header interfaces are respectively connected to the 14th to 17th pins of the controller;

[0115] One end of the seventh capacitor is connected to pin 48 of the controller, and the other end is grounded; one end of the ninth capacitor is connected to pin 7 of the controller, and the other end is grounded; one end of the eleventh capacitor is connected to pin 9 of the controller, and the other end is grounded; one end of the fourteenth capacitor is connected to pin 24 of the controller, and the other end is grounded; one end of the nineteenth resistor is connected to pin 44 of the controller, and the other end is grounded; one end of the twentieth resistor is connected to a 3.3V power supply, and the other end is connected to the ninth capacitor.

[0116] like Figure 4 As shown, Figure 4 This is a schematic diagram of a control circuit provided in an embodiment of the present invention. Figure 4The control circuit includes a controller U5, a power filter circuit and a pin interface J1; the power filter circuit includes a seventh capacitor C7, a ninth capacitor C9, an eleventh capacitor C11, a fourteenth capacitor C14, a nineteenth resistor R19 and a twentieth resistor R20; the controller U5 is an STM32F030C8T6 single-chip microcomputer, is a microcontroller unit (MCU) in the main circuit module of the stabilized power supply, is the control core of the whole system, the first pin of the controller U5 is connected with a backup 3.3V battery, is used for maintaining the data of RTC (real-time clock) and other modules after power failure, and is pulled up to 3.3V through the twentieth resistor R20; the second to fifth pins of the controller U5 are connected with switches K4-K1 respectively; the seventh pin of the controller U5 is a reset pin, is kept at a high level through the twentieth resistor R20 (10kΩ pull-up resistor), is connected with the ninth capacitor C9 to suppress interference, and when external triggering (such as a key) or voltage anomaly occurs, NRST is pulled down to realize single-chip microcomputer reset and restart program execution; the eighth and ninth pins of the controller U5 are connected with a 3.3V power supply through the eleventh capacitor C11; the fourteenth to seventeenth pins of the controller U5 are connected with the first to fourth interfaces of the pin interface J1 respectively; the twentieth and twenty-first pins of the controller U5 are connected with the fourth and third pins of the analog-to-digital converter U1 through the bus I2C2; the twenty-third and twenty-fourth pins of the controller U5 are connected with a 3.3V power supply through the fourteenth capacitor C14; the twenty-fifth pin of the controller U5 is connected with a control load FZ CON; the thirty-third pin of the controller U5 is connected with a buzzer BELL CON; the forty-fourth and forty-eighth pins of the controller U5 are connected with a 3.3V power supply through the seventh capacitor C7 and the nineteenth resistor R19; the forty-fifth and forty-sixth pins of the controller U5 are connected with the third and fourth pins of the analog-to-digital converter U6 through the bus I2C1.

[0117] Specifically, the power conversion circuit includes:

[0118] a rectifier filter circuit, a step-down voltage stabilizing circuit and a protection circuit;

[0119] The rectifier filter circuit includes an input interface, a first rectifier bridge and a fifth electrolytic capacitor;

[0120] The step-down voltage stabilizing circuit includes a second linear voltage stabilizer, a third linear voltage stabilizer, a second capacitor, a sixth electrolytic capacitor, a third capacitor, a fourth electrolytic capacitor, a ninth resistor and a tenth resistor;

[0121] The protection circuit includes a first voltage stabilizing diode, a third resistor, a second electrolytic capacitor and a third electrolytic capacitor;

[0122] The first interface and the third interface of the input interface are connected with the third end and the second end of the first rectifier bridge respectively, the second interface of the input interface is grounded, the first end of the first rectifier bridge is connected with a 12V power supply, the fourth end of the first rectifier bridge is connected with the third resistor and one end of the second electrolytic capacitor, one end of the fifth electrolytic capacitor is connected with a 12V power supply and the other end is grounded.

[0123] The first end of the second linear voltage stabilizer is grounded, the third end of the second linear voltage stabilizer is connected with a 5V power supply, the second end and the fourth end of the second linear voltage stabilizer are connected with a 3.3V power supply, one end of the third capacitor and the fourth electrolytic capacitor is connected with a 3.3V power supply and the other end is grounded, one end of the ninth resistor is connected with a 3.3V power supply and the other end is connected with an alternating current 3.3V power supply, one end of the tenth resistor is connected with the third capacitor and the other end is connected with an alternating current ground;

[0124] The other end of the third resistor is connected with a negative 5V power supply, the other end of the second electrolytic capacitor is grounded, one end of the first voltage stabilizing diode and the third electrolytic capacitor is connected with a negative 5V power supply and the other end is grounded.

[0125] As shown in the accompanying drawings, Figure 5 , Figure 5 is a power conversion circuit schematic diagram provided by an embodiment of the application, the power conversion circuit comprises a rectification filtering circuit, a step-down voltage stabilizing circuit and a protection circuit; Figure 5 The rectification filtering circuit comprises an input interface CON1, a first rectifier bridge DB1 and a fifth electrolytic capacitor E5; the step-down voltage stabilizing circuit comprises a second linear voltage stabilizer U2, a third linear voltage stabilizer U3, a second capacitor C2, a sixth electrolytic capacitor E6, a third capacitor C3, a fourth electrolytic capacitor E4, a ninth resistor R9 and a tenth resistor R10; the protection circuit comprises a first voltage stabilizing diode Z1, a third resistor R3, a second electrolytic capacitor E2 and a third electrolytic capacitor E3;

[0126] The first interface and the third interface of the input interface CON1 are connected with the third end and the second end of the first rectifier bridge DB1 respectively, the second interface of the input interface CON1 is grounded, the first end of the first rectifier bridge DB1 is connected with a 12V power supply, the fourth end of the first rectifier bridge DB1 is connected with the third resistor R3 and one end of the second electrolytic capacitor E2, one end of the fifth electrolytic capacitor E5 is connected with a 12V power supply and the other end is grounded;

[0127] The first end of the second linear voltage stabilizer U2 is grounded, the third end of the second linear voltage stabilizer U2 is connected to a 5V power supply, the second end and the fourth end of the second linear voltage stabilizer U2 are connected to a 3.3V power supply, one end of the third capacitor C3 and the fourth electrolytic capacitor E4 is connected to the 3.3V power supply and the other end is grounded, one end of the ninth resistor R9 is connected to the 3.3V power supply and the other end is connected to the VDDA 3.3V power supply, one end of the tenth resistor R10 is connected to the third capacitor C3 and the other end is connected to the AC ground; the first end of the third linear voltage stabilizer U3 is connected to a 12V power supply, the second end of the third linear voltage stabilizer U3 is grounded, the third end of the third linear voltage stabilizer U3 is connected to a 5V power supply, one end of the second capacitor C2 and the sixth electrolytic capacitor E6 is connected to the 5V power supply and the other end is grounded;

[0128] The other end of the third resistor R3 is connected to a negative 5V power supply, the other end of the second electrolytic capacitor E2 is grounded, one end of the first voltage stabilizing diode Z1 and the third electrolytic capacitor E3 is connected to the negative 5V power supply and the other end is grounded.

[0129] It can be understood that the power conversion circuit gradually converts the input voltage into multiple power supplies required by the system (such as +12V, +5V, 3.3V, VDDA_3.3V), DB1 converts the input AC voltage (or voltage containing AC component) into unidirectional pulsating DC (regardless of the polarity of the input voltage, the output is always positive voltage to the +12V terminal); E5 filters and smooths the pulsating DC voltage, reduces voltage fluctuation (large-capacity electrolytic capacitor is suitable for filtering low-frequency ripple); the voltage reduction and stabilization circuit is used for stabilizing the power supply voltage and performing power supply filtering, avoiding digital circuit noise interference to the analog circuit. The protection circuit uses the reverse breakdown characteristic of the voltage stabilizing tube to stabilize the voltage of the -5V terminal at 5.1V and stabilize the negative power supply voltage.

[0130] Specifically, the controller is a single-chip microcomputer.

[0131] Specifically, the bidirectional communication module realizes bidirectional communication interaction through an I2C bus.

[0132] The internal self-calibration system of the digital voltage stabilizing power supply disclosed by the embodiment comprises a voltage stabilizing power supply main circuit module, a high-precision resistor module and a bidirectional communication module; the voltage stabilizing power supply main circuit module is used to send preset calibration parameters to the high-precision resistor module; the high-precision resistor module is used to receive the preset calibration parameters, match calibration data according to the preset calibration parameters, and send the calibration data to the voltage stabilizing power supply main circuit module; the voltage stabilizing power supply main circuit module is also used to receive the calibration data, calculate calibration deviation according to the calibration data, and calibrate the voltage stabilizing power supply according to the calibration deviation; and the bidirectional communication module is used to provide communication interaction for the high-precision resistor module and the voltage stabilizing power supply main circuit module to realize data interaction. Without relying on external actual working load or before connecting external load, fast, automatic and high-precision internal self-calibration can be realized to ensure that the power supply can provide stable and accurate output from power-on, and the reliability and user experience of the power supply are fundamentally improved.

[0133] Reference is made to Figure 6 , Figure 6 is a flow diagram of a digital voltage stabilizing power supply internal self-calibration system control method provided by the embodiment, and the digital voltage stabilizing power supply internal self-calibration system control method comprises:

[0134] S1, when receiving a self-calibration trigger instruction, the voltage stabilizing power supply main circuit module sends preset calibration parameters to the high-precision resistor module through the bidirectional communication module;

[0135] S2, the high-precision resistor module receives the preset calibration parameters, matches calibration data according to the preset calibration parameters, and sends the calibration data to the voltage stabilizing power supply main circuit module through the bidirectional communication module;

[0136] S3, the voltage stabilizing power supply main circuit module receives the calibration data, calculates calibration deviation according to the calibration data, and calibrates the voltage stabilizing power supply according to the calibration deviation.

[0137] The digital voltage stabilizing power supply internal self-calibration system control method provided by the embodiment can realize all processes of the digital voltage stabilizing power supply internal self-calibration system of the above-mentioned embodiment, and the functions and technical effects of each module in the system are the same as those of the digital voltage stabilizing power supply internal self-calibration method of the above-mentioned embodiment, which will not be repeated here.

[0138] The above is the preferred embodiment of the present application, and it should be noted that those skilled in the art can make some improvements and refinements without departing from the principles of the present application, and these improvements and refinements are also considered within the protection scope of the present application.

Claims

1. An internal self-calibration system for a digital regulated power supply, characterized in that, include: The main circuit module of the regulated power supply, the high-precision resistor module, and the bidirectional communication module; The main circuit module of the regulated power supply is used to send the preset calibration parameters to the high-precision resistor module; The high-precision resistor module is used to receive the preset calibration parameters, match calibration data according to the preset calibration parameters, and send the calibration data to the regulated power supply main circuit module. The main circuit module of the regulated power supply is also used to receive the calibration data, calculate the calibration deviation based on the calibration data, and calibrate the regulated power supply based on the calibration deviation. The bidirectional communication module is used to provide communication interaction between the high-precision resistor module and the regulated power supply main circuit module for data exchange. The high-precision resistor module includes: High-precision fixed-resistance calibration load, electronic switching circuit, and sampling circuit; The high-precision fixed-resistance calibration load is used to provide a stable reference calibration load for the regulated power supply. The electronic switching circuit is used to control the connection status between the high-precision fixed resistance calibration load and the power output circuit. The sampling circuit is used to measure the current and voltage of the high-precision fixed resistance calibration load according to the preset calibration parameters, and to obtain calibration data based on the current and voltage. If the internal self-calibration system further includes a PWM signal control circuit; The main circuit module of the regulated power supply is further configured to generate control commands based on the calibration deviation and send the control commands to the PWM signal control circuit. The PWM signal control circuit is used to receive the control command and generate an adjustment PWM signal according to the control command to calibrate the regulated power supply.

2. The internal self-calibration system of the digital regulated power supply as described in claim 1, characterized in that, The bidirectional communication module achieves bidirectional communication interaction via the I2C bus.

3. The internal self-calibration system of the digital regulated power supply as described in claim 2, characterized in that, The sampling circuit includes: Signal acquisition circuit, load control circuit, and voltage divider circuit; The signal acquisition circuit includes an analog-to-digital converter, a first resistor, a second resistor, a first capacitor, and a first electrolytic capacitor; The voltage divider circuit includes a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, and an eighth resistor; The load control circuit includes a first relay, a first diode, a second diode, a second switching transistor, and a thirteenth resistor; In this configuration, pin 1 of the analog-to-digital converter (ADC) is connected to the first end of the seventh resistor; pins 2 and 6 of the ADC are grounded; pin 3 of the ADC is connected to the first end of the first resistor and is connected to the main circuit module of the regulated power supply via bus I2C2 in the I2C bus; pin 4 of the ADC is connected to the first end of the second resistor and is connected to the main circuit module of the regulated power supply via bus I2C2 in the I2C bus; pin 5 of the ADC is connected to a 5V power supply; the second end of the first resistor is connected to a 5V power supply; the first end of the first capacitor is connected to a 5V power supply and the second end of the first capacitor is grounded; the first end of the first electrolytic capacitor is connected to a 5V power supply and the second end of the first electrolytic capacitor is grounded. The first end of the seventh resistor is connected to the first end of the sixth resistor, and the second end of the seventh resistor is grounded; the second end of the sixth resistor is connected to the first end of the fifth resistor, the second end of the fifth resistor is connected to the first ends of the fourth resistor and the eighth resistor, the second end of the fourth resistor is connected to the red terminal of the power supply and the third end of the first relay, and the second end of the eighth resistor is grounded. The first terminal of the first relay is connected to the first terminal of the first diode and the first terminal of the second diode. The second terminal of the first diode is connected to a 12V power supply. The second terminal of the second diode is connected to the second terminal of the first relay and the collector of the second switching transistor. The emitter of the second switching transistor is grounded. The base of the second switching transistor is connected to the first terminal of the thirteenth resistor. The second terminal of the thirteenth resistor is connected to the control load.

4. The internal self-calibration system of the digital regulated power supply as described in claim 2, characterized in that, The sampling circuit includes: Signal acquisition and filtering circuit, signal amplification circuit, and ADC acquisition circuit; The signal acquisition and filtering circuit includes a sampling resistor, a seventeenth resistor, a twenty-second resistor, an eighth capacitor, a twelfth capacitor, an eighteenth resistor, and a twenty-third resistor; The signal amplification circuit includes an operational amplifier, a sixteenth resistor, a first adjustable resistor, a twenty-fourth resistor, a fourth capacitor, a sixth capacitor, a tenth capacitor, and a thirteenth capacitor; The ADC acquisition circuit includes an analog-to-digital converter, a fourteenth resistor, a fifteenth resistor, a fifth capacitor, and a seventh electrolytic capacitor; Wherein, one end of the sampling resistor is connected to one end of the 22nd resistor and ground; the other end of the sampling resistor is connected to one end of the 17th resistor; the other end of the 22nd resistor is connected to one end of the 23rd resistor and one end of the 12th capacitor; the other end of the 12th capacitor is grounded; the other end of the 23rd resistor is connected to the second interface of the operational amplifier, one end of the 13th capacitor, and one end of the 24th resistor; the other end of the 17th resistor is connected to one end of the 8th capacitor and one end of the 18th resistor; the other end of the 8th capacitor is grounded; and the other end of the 18th resistor is connected to one end of the 16th resistor and the 6th capacitor, and the third interface of the operational amplifier. The first and eighth interfaces of the operational amplifier are respectively connected to the third and first ends of the first adjustable resistor. The seventh and fourth interfaces of the operational amplifier are respectively connected to a positive and negative 5V power supply. The sixth interface of the operational amplifier is connected to the other end of the thirteenth capacitor and the twenty-fourth resistor, as well as the first pin of the analog-to-digital converter. One end of the tenth capacitor is connected to a negative 5V power supply and the other end is grounded. One end of the fourth capacitor is connected to a positive 5V power supply and the other end is grounded. The second end of the first adjustable resistor is connected to a positive 5V power supply. The other end of the sixteenth resistor and the sixth capacitor is grounded. The analog-to-digital converter (ADC) has pins 2 and 6 grounded. Pins 3 and 4 of the ADC are connected to one end of the fourteenth and fifteenth resistors, respectively, and are connected to the main circuit module of the regulated power supply via bus I2C1 in the I2C bus. Pin 5 of the ADC is connected to a 5V power supply. The other ends of the fourteenth and fifteenth resistors are connected to a 5V power supply. One end of the fifth capacitor and the seventh electrolytic capacitor is connected to a 5V power supply, and the other end is grounded.

5. The internal self-calibration system of the digital regulated power supply as described in claim 1, characterized in that, The regulated power supply main circuit module includes: Power conversion circuit and control circuit; The control circuit includes a controller, a power filter circuit, and a pin header interface; The power supply filtering circuit includes a seventh capacitor, a ninth capacitor, an eleventh capacitor, a fourteenth capacitor, a nineteenth resistor, and a twentieth resistor. The first to fourth pin header interfaces are respectively connected to the 14th to 17th pins of the controller; One end of the seventh capacitor is connected to pin 48 of the controller, and the other end is grounded; one end of the ninth capacitor is connected to pin 7 of the controller, and the other end is grounded; one end of the eleventh capacitor is connected to pin 9 of the controller, and the other end is grounded; one end of the fourteenth capacitor is connected to pin 24 of the controller, and the other end is grounded; one end of the nineteenth resistor is connected to pin 44 of the controller, and the other end is grounded; one end of the twentieth resistor is connected to a 3.3V power supply, and the other end is connected to the ninth capacitor.

6. The internal self-calibration system of the digital regulated power supply as described in claim 5, characterized in that, The power conversion circuit includes: Rectifier and filter circuit, step-down voltage regulator circuit and protection circuit; The rectifier and filter circuit includes an input interface, a first rectifier bridge, and a fifth electrolytic capacitor; The buck regulator circuit includes a second linear regulator, a third linear regulator, a second capacitor, a sixth electrolytic capacitor, a third capacitor, a fourth electrolytic capacitor, a ninth resistor, and a tenth resistor. The protection circuit includes a first Zener diode, a third resistor, a second electrolytic capacitor, and a third electrolytic capacitor; The first and third interfaces of the input interface are respectively connected to the third and second ends of the first rectifier bridge, the second interface of the input interface is grounded, the first end of the first rectifier bridge is connected to a 12V power supply, the fourth end of the first rectifier bridge is connected to the third resistor and one end of the second electrolytic capacitor, and one end of the fifth electrolytic capacitor is connected to the 12V power supply and the other end is grounded. The first terminal of the second linear regulator is grounded, the third terminal of the second linear regulator is connected to a 5V power supply, the second and fourth terminals of the second linear regulator are connected to a 3.3V power supply, one end of the third capacitor and the fourth electrolytic capacitor are connected to a 3.3V power supply and the other end is grounded, one end of the ninth resistor is connected to a 3.3V power supply and the other end is connected to an AC 3.3V power supply, one end of the tenth resistor is connected to the third capacitor and the other end is AC grounded; the first terminal of the third linear regulator is connected to a 12V power supply, the second terminal of the third linear regulator is grounded, the third terminal of the third linear regulator is connected to a 5V power supply, and one end of the second capacitor and the sixth electrolytic capacitor are connected to a 5V power supply and the other end is grounded. The other end of the third resistor is connected to a negative 5V power supply, the other end of the second electrolytic capacitor is grounded, and one end of the first Zener diode and one end of the third electrolytic capacitor are connected to a negative 5V power supply and the other end is grounded.

7. The internal self-calibration system of the digital regulated power supply as described in claim 5, characterized in that, The controller is a microcontroller.

8. A control method for an internal self-calibration system of a digital regulated power supply according to any one of claims 1-7, characterized in that, include: When a self-calibration trigger command is received, the main circuit module of the regulated power supply will send the preset calibration parameters to the high-precision resistor module through the bidirectional communication module. The high-precision resistor module receives the preset calibration parameters, matches calibration data according to the preset calibration parameters, and sends the calibration data to the regulated power supply main circuit module through the bidirectional communication module. The main circuit module of the regulated power supply receives the calibration data, calculates the calibration deviation based on the calibration data, and calibrates the regulated power supply based on the calibration deviation.

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