A power management output regulation feedback control circuit and system

Abstract

The application discloses a power management output regulation feedback control circuit, comprising a power conversion module, a sampling module and a feedback regulation module, and relates to the technical field of power management. The sampling module generates a sampling signal according to the output voltage of the power conversion module, a digital adjustable proportional unit in the feedback regulation module receives a control signal to adjust the control value of itself, changes the corresponding relationship between the output voltage and the feedback voltage, the feedback voltage is input to the feedback end of the power conversion module, and the power conversion module adjusts the output voltage according to the feedback voltage. The program regulation of the output voltage is realized by adjusting the control signal to change the feedback voltage, the structure of the sampling module does not need to be changed, the feedback mechanism of the original power conversion module is reserved, only the feedback regulation module is additionally arranged, the power conversion circuit with the feedback control function is suitable for various types, and good universality and expansibility are achieved.

Description

Technical Field

[0001] This invention relates to the field of power management technology, and in particular to a power management output regulation feedback control circuit and system. Background Technology

[0002] Power conversion circuits are widely used in power management systems to transform input and output voltages. Common types include buck-boost and low-dropout linear regulators. Existing power conversion circuits typically incorporate a sampling module to sample the output voltage, generate a feedback voltage, and input it to the power converter's feedback terminal. The power converter then adjusts the output voltage based on the feedback voltage, thereby achieving stable output voltage control.

[0003] like Figure 1 As shown, the first sampling resistor R8 and the second sampling resistor R9 constitute a sampling module. The connection point of the first sampling resistor R8 and the second sampling resistor R9 serves as the output terminal of the sampling module, outputting a feedback voltage to the feedback terminal FB of the power conversion control chip, as shown. Figure 2 As shown, the feedback voltage is input to the inverting input of the error amplifier EA inside the control chip. The non-inverting input of the error amplifier EA is connected to the reference voltage Reference. By comparing the feedback voltage with the reference voltage Reference, and executing corresponding control actions based on the comparison result, the output voltage VCC OUT is controlled. The output voltage of this power conversion circuit is determined by the first sampling resistor R8 and the second sampling resistor R9 in the sampling module. When adjusting the output voltage, it is usually necessary to replace the sampling resistors. However, replacing the sampling resistors requires manual disassembly and soldering, making it impossible to adjust the output voltage in real time during circuit operation. This makes it difficult to meet the application requirements for dynamic adjustment and automatic control of the output voltage in various scenarios. Summary of the Invention

[0004] The purpose of this invention is to provide a power management output regulation feedback control circuit and system to solve the problem that existing power conversion circuits require manual replacement of the sampling resistor to adjust the output voltage, resulting in the inability to adjust the output voltage in real time.

[0005] To solve the above technical problems, the present invention provides a power management output regulation feedback control circuit, comprising: Power conversion module, sampling module, feedback regulation module; The output terminal of the power conversion module is connected to the input terminal of the sampling module, and the feedback terminal of the power conversion module is connected to the output terminal of the feedback adjustment module, which is used to adjust the output voltage of the output terminal according to the feedback voltage received by the feedback terminal. The sampling module is used to generate a sampling signal based on the output voltage; The feedback adjustment module is located between the output terminal of the sampling module and the feedback terminal of the power conversion module; the feedback adjustment module includes an arithmetic unit and a digitally adjustable proportional unit, which is used to change the correspondence between the output voltage and the feedback voltage by adjusting the control value of the digitally adjustable proportional unit to obtain the feedback voltage.

[0006] Optionally, the first and second input terminals of the digitally adjustable proportional unit are connected to a reference voltage and ground, respectively; the control terminal of the digitally adjustable proportional unit is used to receive a control signal; the output terminal of the digitally adjustable proportional unit is connected to the first input terminal of the arithmetic unit; the second input terminal of the arithmetic unit is used to receive a sampling signal; and the output terminal of the arithmetic unit is connected to the feedback terminal of the power conversion module.

[0007] Optionally, the first and second input terminals of the digitally adjustable proportional unit are respectively connected to the output terminal of the arithmetic unit and ground; the control terminal of the digitally adjustable proportional unit is used to receive the control signal; the output terminal of the digitally adjustable proportional unit is connected to the feedback terminal of the power conversion module; and the input terminal of the arithmetic unit is used to receive the sampling signal.

[0008] Optional, also includes: A voltage follower, the input of which is connected to the output of the digitally adjustable proportional unit, and the output of which is connected to the first input of the arithmetic unit, is used to buffer and isolate the digitally adjustable proportional unit from the arithmetic unit.

[0009] Optionally, the operational unit includes: a first operational amplifier, a first resistor, a second resistor, and a third resistor; The output terminal of the first operational amplifier is connected to the first terminal of the first resistor and serves as the output terminal of the operational unit; the inverting input terminal of the first operational amplifier is connected to the second terminal of the first resistor and the first terminal of the second resistor; the second terminal of the second resistor is grounded; the non-inverting input terminal of the first operational amplifier is connected to the first terminal of the third resistor and serves as the second input terminal of the operational unit; the second terminal of the third resistor serves as the first input terminal of the operational unit.

[0010] Optionally, the operational unit includes: a second operational amplifier, a fourth resistor, and a fifth resistor; The output terminal of the second operational amplifier is connected to the first terminal of the fourth resistor and serves as the output terminal of the operational unit; the inverting input terminal of the second operational amplifier is connected to the second terminal of the fourth resistor and the first terminal of the fifth resistor; the second terminal of the fifth resistor is grounded; the non-inverting input terminal of the second operational amplifier serves as the input terminal of the operational unit.

[0011] Optionally, the voltage follower includes: Third operational amplifier, sixth resistor, and seventh resistor; The non-inverting input of the third operational amplifier is connected to the first terminal of the sixth resistor; the second terminal of the sixth resistor serves as the input of the voltage follower; the inverting input of the third operational amplifier is connected to the first terminal of the seventh resistor; the second terminal of the seventh resistor is connected to the output of the third operational amplifier and serves as the output of the voltage follower.

[0012] Optionally, the digitally adjustable proportional unit is a digital potentiometer; the high end of the digital potentiometer serves as the first input terminal of the digitally adjustable proportional unit; the low end of the digital potentiometer serves as the second input terminal of the digitally adjustable proportional unit; the common terminal of the digital potentiometer serves as the output terminal of the digitally adjustable proportional unit; and the control terminal of the digital potentiometer serves as the control terminal of the digitally adjustable proportional unit.

[0013] Optionally, the sampling module includes: The eighth and ninth resistors; The first end of the eighth resistor serves as the input terminal of the sampling module; the second end of the eighth resistor is connected to the first end of the ninth resistor; the second end of the ninth resistor is grounded; the connection node between the eighth resistor and the ninth resistor serves as the output terminal of the sampling module.

[0014] To address the aforementioned technical problems, the present invention also provides a power management output regulation feedback control system, including a power supply, a controller, and the aforementioned power management output regulation feedback control circuit; the power supply is connected to the input terminal of the power conversion module; the output terminal of the controller is connected to the control terminal of a digitally adjustable proportional unit, for outputting a control signal to control the control value of the digitally adjustable proportional unit.

[0015] This invention provides a power management output regulation feedback control circuit, including a power conversion module, a sampling module, and a feedback regulation module. The sampling module generates a sampling signal based on the output voltage of the power conversion module. The digitally adjustable proportional unit in the feedback regulation module receives the control signal to adjust its own control value, changing the correspondence between the output voltage and the feedback voltage. The feedback voltage is input to the feedback terminal of the power conversion module, and the power conversion module adjusts its output voltage according to the feedback voltage. As the control signal changes, the feedback voltage generated by the feedback regulation module changes accordingly, thereby causing the power conversion module to output a corresponding output voltage. By adjusting the control signal to change the feedback voltage input to the feedback terminal of the power conversion module, the output voltage is regulated without changing the structure of the sampling module, achieving programmatic regulation of the output voltage, which is convenient for use with automated control equipment. Furthermore, this solution retains the feedback regulation mechanism of the power conversion module and achieves feedback voltage regulation by adding a feedback regulation module without changing the basic structure of the power conversion module. Therefore, it can be applied to various power conversion circuits with feedback control functions, improving the versatility of the solution.

[0016] Furthermore, the power management output regulation feedback control system provided by this invention has the same effect as above. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings used in the prior art and embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of an existing power conversion circuit; Figure 2 This is a diagram of the internal topology of the control chip in an existing power conversion circuit. Figure 3 A schematic diagram of a power management output regulation feedback control circuit provided by the present invention; Figure 4 A schematic diagram of another power management output regulation feedback control circuit provided by the present invention. Detailed Implementation

[0019] The core of this invention is to provide a power management output regulation feedback control circuit and system.

[0020] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] Power conversion circuits are widely used in power management systems to transform input and output voltages. Common types include buck-boost and low-dropout linear regulators. Existing power conversion circuits typically incorporate a sampling module to sample the output voltage, generate a feedback voltage, and input it to the power converter's feedback terminal. The power converter then adjusts the output voltage based on the feedback voltage, thereby achieving stable output voltage control.

[0022] Figure 1 A schematic diagram of an existing power conversion circuit, such as... Figure 1 As shown, the first sampling resistor R8 and the second sampling resistor R9 constitute the sampling module. The connection point of the first sampling resistor R8 and the second sampling resistor R9 serves as the output terminal of the sampling module, outputting a feedback voltage to the feedback terminal FB of the power conversion control chip. The power conversion module adopts a boost DC-DC converter circuit, including a power conversion control chip, a power switch Q1, an inductor L1, and an external parameter configuration network. The power conversion control chip generates a drive signal based on the feedback voltage received at the feedback terminal FB, controlling the on and off states of the power switch Q1 to achieve closed-loop regulation of the output voltage. The inductor L1 stores and releases energy, working with the power switch Q1 and the rectifier diode D1 to complete the boost energy transfer. The output filter capacitor C8 filters the output voltage, improving its stability. The input filter capacitor C5 is connected to the input power supply terminal to stabilize the input voltage and reduce input ripple; the bypass capacitor C6 is connected to the BP pin of the control chip to stabilize the internal bias power supply and improve drive stability. Resistor R13 is used for current detection; resistor R14 is used for gate driving; resistor R15 and capacitor C7 are used for transmitting and filtering the current sampling signal. In addition, resistors R11 and R10, capacitors C3 and C4 are connected to the RC and SS pins of the control chip to form an oscillation frequency setting and soft-start network; resistors R12, capacitors C2 and C1 form an error amplifier compensation network to improve the closed-loop stability of the system. Figure 2 The internal topology of the control chip in an existing power conversion circuit is shown below. Figure 2As shown, the feedback voltage is input to the inverting input of the error amplifier EA inside the control chip. The non-inverting input of the error amplifier EA is input to the reference voltage Vref. By comparing the feedback voltage with the reference voltage Vref, and executing corresponding control actions based on the comparison result, the output voltage VCC OUT is controlled. The output voltage of this power conversion circuit is determined by the first sampling resistor R8 and the second sampling resistor R9 in the sampling module. When adjusting the output voltage, it is usually necessary to replace the sampling resistors. However, replacing the sampling resistors requires manual disassembly and soldering, making it impossible to adjust the output voltage in real time during circuit operation. This makes it difficult to meet the application requirements for dynamic adjustment and automatic control of the output voltage in various scenarios.

[0023] To address the aforementioned technical problems, this invention provides a power management output regulation feedback control circuit.

[0024] For details, please see Figure 3 , Figure 3 This is a schematic diagram of a power management output regulation feedback control circuit provided by the present invention.

[0025] like Figure 3 As shown, the circuit includes: Power conversion module 1, sampling module 2, feedback regulation module 3; The output terminal of the power conversion module 1 is connected to the input terminal of the sampling module 2, and the feedback terminal FB of the power conversion module 1 is connected to the output terminal of the feedback adjustment module 3, which is used to adjust the output voltage Vout of the output terminal according to the feedback voltage V1 received by the feedback terminal FB. Sampling module 2 is used to generate a sampling signal based on the output voltage Vout; The feedback adjustment module 3 is located between the output terminal of the sampling module 2 and the feedback terminal FB of the power conversion module 1. The feedback adjustment module 3 includes an arithmetic unit and a digitally adjustable proportional unit, which is used to change the correspondence between the output voltage Vout and the feedback voltage V1 by adjusting the control value of the digitally adjustable proportional unit to obtain the feedback voltage V1.

[0026] Specifically, in traditional power converters, the sampling signal generated by sampling module 2 is usually directly fed back to the feedback terminal FB of power conversion module 1. Power conversion module 1 adjusts the operating state of its internal boost or buck circuit based on the deviation between the feedback voltage V1 and the internal reference voltage to stabilize the feedback voltage V1 at a preset value, thereby determining the output voltage Vout. Therefore, there is a fixed correspondence between the output voltage Vout and the feedback voltage V1. When it is necessary to change the output voltage Vout, it is usually necessary to change the feedback voltage division ratio in sampling module 2. In this embodiment, a feedback adjustment module 3 is added between sampling module 2 and power conversion module 1. Instead of directly changing the voltage division structure of sampling module 2, the feedback adjustment module 3 adjusts the sampling signal according to the control signal, so that the feedback voltage V1 received by the feedback terminal FB changes controllably relative to the sampling signal, thereby changing the correspondence between the output voltage Vout and the feedback voltage V1. The feedback adjustment module 3 includes an arithmetic unit and a digitally adjustable proportional unit. By changing the control value of the digitally adjustable proportional unit, the way the feedback adjustment module 3 generates the feedback voltage V1 can be changed, thereby changing the correspondence between the output voltage Vout and the feedback voltage V1. When the feedback adjustment module 3 changes the feedback voltage V1, the closed-loop adjustment process of the power conversion module 1 will re-establish a new steady-state balance, so that the output voltage Vout will be automatically adjusted to the target value corresponding to the new feedback voltage V1.

[0027] It should be noted that this embodiment does not limit the specific topology of the power conversion module 1. Any power conversion circuit that receives the feedback voltage V1 through the feedback terminal FB and adjusts the output voltage Vout according to the comparison result between the feedback voltage V1 and the internal reference voltage can be used as the power conversion module 1 in this embodiment. As an example, the power conversion module 1 can be a BUCK buck converter circuit, a BOOST boost converter circuit, or any power conversion circuit with feedback regulation function, such as an LDO linear regulator circuit. It should be noted that the sampling module 2 can be implemented using any circuit structure that can generate a related sampling signal based on the output voltage Vout; this embodiment does not limit it. As an example, such as Figure 3 As shown, the sampling module 2 may include an eighth resistor R8 and a ninth resistor R9. The connection node of the eighth resistor R8 and the ninth resistor R9 serves as the output terminal of the sampling module 2, outputting a sampling signal. At this time, the sampling module 2 samples the output voltage Vout according to the voltage division ratio of the voltage divider circuit composed of the eighth resistor R8 and the ninth resistor R9.

[0028] It should be noted that the arithmetic unit and the digitally adjustable proportional unit in the feedback adjustment module 3 can have different connection relationships. For example, as Figure 3As shown, the first and second input terminals of the digital adjustable proportional unit are connected to the reference voltage Vref and ground, respectively. The digital adjustable proportional unit performs voltage division on the reference voltage Vref according to the control value corresponding to the control signal, and outputs the resulting bias voltage V2 through its output terminal. The bias voltage V2 is connected to the first input terminal of the arithmetic unit, and the sampling signal output by the sampling module 2 is connected to the second input terminal of the arithmetic unit. The arithmetic unit performs arithmetic processing on the bias voltage V2 and the sampling signal to obtain the feedback voltage V1, and outputs it to the feedback terminal FB of the power conversion module 1. For example, please refer to... Figure 4 , Figure 4 A schematic diagram of another power management output regulation feedback control circuit provided by the present invention, as shown below. Figure 4 As shown, the first and second input terminals of the digital adjustable proportional unit are connected to the output terminal of the arithmetic unit and ground, respectively. The digital adjustable proportional unit performs voltage division processing on the signal output by the arithmetic unit according to the control value corresponding to the control signal, and outputs the divided signal to the feedback terminal FB of the power conversion module 1 as the feedback voltage V1. The input terminal of the arithmetic unit is connected to the sampling signal output by the sampling module 2, and the sampled signal is processed and output from its output terminal. Both of these connection relationships can change the correspondence between the output voltage Vout and the feedback voltage V1 by changing the control value of the digital adjustable proportional unit, thereby adjusting the output voltage Vout without changing the internal structure of the sampling module 2. As an example, the digital adjustable proportional unit can be implemented using a digital potentiometer. The digital potentiometer has a high-side terminal H, a low-side terminal L, a common terminal W, and a control terminal. The high-side terminal H serves as the first input terminal of the digital adjustable proportional unit, the low-side terminal L serves as the second input terminal, the common terminal W serves as the output terminal, and the control terminal serves as the control terminal for receiving control signals. The digital potentiometer internally selects different tap positions through control signals, changing the voltage division ratio of the common terminal W relative to the high-side H and low-side L, thereby changing the control value of the digitally adjustable proportional unit.

[0029] As can be seen, this embodiment regulates the output voltage Vout by adjusting the feedback voltage V1 at the feedback terminal FB of the input power conversion module 1 through adjusting the control signal, without changing the structure of the sampling module 2. This achieves programmed adjustment of the output voltage Vout, facilitating its use with automated control equipment. Furthermore, while retaining the feedback adjustment mechanism of the power conversion module 1, this solution adds a feedback adjustment module 3 to adjust the feedback voltage V1 without altering the basic structure of the power conversion module 1. Therefore, it is applicable to various power conversion circuits with feedback control functions, improving the versatility of the solution.

[0030] As an optional embodiment, the first and second input terminals of the digital adjustable proportional unit are connected to the reference voltage Vref and ground, respectively. The control terminal of the digital adjustable proportional unit is used to receive control signals, and the output terminal of the digital adjustable proportional unit is connected to the first input terminal of the arithmetic unit. The second input terminal of the arithmetic unit is used to receive sampling signals, and the output terminal of the arithmetic unit is connected to the feedback terminal FB of the power conversion module 1.

[0031] Specifically, such as Figure 3 As shown, the first and second input terminals of the digital adjustable proportional unit are connected to the reference voltage Vref and ground, respectively. The digital adjustable proportional unit performs voltage division on the reference voltage Vref according to the control value corresponding to the control signal, and outputs the resulting bias voltage V2 through its output terminal. The bias voltage V2 is connected to the first input terminal of the arithmetic unit, and the sampling signal output by the sampling module 2 is connected to the second input terminal of the arithmetic unit. The arithmetic unit performs arithmetic processing on the bias voltage V2 and the sampling signal to obtain the feedback voltage V1, and outputs it to the feedback terminal FB of the power conversion module 1. Under this connection, the digital adjustable proportional unit is not directly placed on the transmission path of the sampling signal, but instead generates a separate bias voltage V2 related to its control value. The arithmetic unit then superimposes this bias voltage V2 with the sampling signal to obtain the feedback voltage V1. Therefore, changing the control value of the digital adjustable proportional unit changes the magnitude of the bias voltage V2 involved in the calculation, thereby changing the calculated feedback voltage V1, and ultimately changing the output voltage Vout.

[0032] As can be seen, in this embodiment, the bias voltage V2 is adjusted by using a digitally adjustable proportional unit, and then the corresponding feedback voltage V1 is obtained by superposition calculation by the arithmetic unit, thereby realizing the adjustment of the output voltage Vout.

[0033] As an optional embodiment, the first and second input terminals of the digital adjustable proportional unit are respectively connected to the output terminal of the arithmetic unit and ground. The control terminal of the digital adjustable proportional unit is used to receive control signals, and the output terminal of the digital adjustable proportional unit is connected to the feedback terminal FB of the power conversion module 1. The input terminal of the arithmetic unit is used to receive sampling signals.

[0034] Specifically, such as Figure 4As shown, the first and second input terminals of the digital adjustable proportional unit are connected to the output terminal of the arithmetic unit and ground, respectively. The digital adjustable proportional unit performs voltage division processing on the signal output by the arithmetic unit according to the control value corresponding to the control signal, and outputs the divided signal to the feedback terminal FB of the power conversion module 1 as the feedback voltage V1. The input terminal of the arithmetic unit is connected to the sampling signal output by the sampling module 2, and the sampled signal is processed and output by its output terminal. Under this connection, the digital adjustable proportional unit is positioned on the signal path between the output terminal of the arithmetic unit and the feedback terminal FB of the power conversion module 1, directly dividing the signal output by the arithmetic unit to obtain the feedback voltage V1. Therefore, changing the control value of the digital adjustable proportional unit directly changes the voltage division ratio between the output signal of the arithmetic unit and the feedback voltage V1, that is, directly changes the correspondence between the feedback voltage V1 and the output signal of the arithmetic unit, thereby changing the output voltage Vout.

[0035] As can be seen, in this embodiment, since the digital adjustable proportional unit is set on the signal path between the output terminal of the arithmetic unit and the feedback terminal FB of the power conversion module 1, the feedback voltage V1 is obtained by directly dividing the signal output by the arithmetic unit. Therefore, the circuit structure is simple and there is no need to configure a separate reference voltage Vref input for the digital adjustable proportional unit, which can reduce the number of circuit components and simplify the circuit structure.

[0036] As an optional embodiment, it also includes: A voltage follower is used to buffer and isolate the digitally adjustable proportional unit from the arithmetic unit. The voltage follower's input is connected to the output of the digitally adjustable proportional unit, and its output is connected to the first input of the arithmetic unit.

[0037] Specifically, the output impedance of the digital adjustable proportional unit (DPP) varies with the control value, and its driving capability is relatively weak. If its output is directly connected to the input of the arithmetic unit, the input impedance and current of the arithmetic unit will affect the output signal of the DPP. To solve this problem, a voltage follower is used for buffer isolation between the output of the DPP and the input of the arithmetic unit. The voltage follower has the characteristics of high input impedance and low output impedance: the high input impedance means it draws almost no current from the digital potentiometer taps, avoiding affecting the accuracy of its voltage division; the low output impedance allows it to stably drive the subsequent arithmetic unit, unaffected by the load of the subsequent stage.

[0038] As can be seen, this embodiment ensures that the bias voltage V2 output by the digitally adjustable proportional unit is accurately and stably transmitted to the arithmetic unit by setting a voltage follower, thereby improving the adjustment accuracy and reliability of the overall circuit output voltage Vout.

[0039] As an optional embodiment, the arithmetic unit includes: a first operational amplifier U1, a first resistor R1, a second resistor R2, and a third resistor R3; The output terminal of the first operational amplifier U1 is connected to the first terminal of the first resistor R1 and serves as the output terminal of the operational unit; the inverting input terminal of the first operational amplifier U1 is connected to the second terminal of the first resistor R1 and the first terminal of the second resistor R2; the second terminal of the second resistor R2 is grounded; the non-inverting input terminal of the first operational amplifier U1 is connected to the first terminal of the third resistor R3 and serves as the second input terminal of the operational unit; the second terminal of the third resistor R3 serves as the first input terminal of the operational unit.

[0040] Specifically, in this embodiment, the sampling module 2 adopts a voltage divider structure composed of the eighth resistor R8 and the ninth resistor R9; the operational unit specifically includes a first operational amplifier U1, a first resistor R1, a second resistor R2, and a third resistor R3; the digitally adjustable proportional unit is implemented using a digital potentiometer, with the resistance between the high-side H and low-side L of the digital potentiometer being Rhl, the resistance between the high-side H and the common terminal W being Rhw, and the resistance between the low-side L and the common terminal W being Rwl. The digital potentiometer internally contains a resistor string composed of multiple resistor units of equal resistance value connected in series, and this resistor string is divided into multiple equally divided resistance value segments. In this embodiment, taking a division into 256 equally divided resistance value segments as an example, the control value K ranges from 0 to 255, and correspondingly, the resistance between the low-side L and the common terminal W satisfies: ; The high-side (H) of the digital potentiometer is connected to the reference voltage Vref, and the low-side (L) is connected to ground. Therefore, the bias voltage V2 output from the common terminal (W) is: ; The bias voltage V2 and the sampling signal output by sampling module 2 are respectively connected to the arithmetic unit composed of the first operational amplifier U1, the first resistor R1, the second resistor R2, and the third resistor R3. The two signals are processed to obtain the feedback voltage V1, which is then output to the feedback terminal FB of power conversion module 1. Analysis of the input-output network of the first operational amplifier shows that the feedback voltage V1 output to power conversion module 1 satisfies: ; Where Vout is the output voltage Vout of power conversion module 1, and Vref is the external input reference voltage Vref. Since the feedback voltage V1 is equal to the reference voltage Vfb of the error amplifier inside power conversion module 1 under the adjustment of power conversion module 1, the following relationship is obtained: ; The output voltage Vout can be obtained from the above equation: ; As shown in the above formula, changing the control value K allows for programmed continuous adjustment of the output voltage Vout. In practical applications, resistor matching is also required to ensure that the calculated value of the output voltage Vout when K=0 equals the actual maximum output value.

[0041] As can be seen, this embodiment uses a first operational amplifier U1, a first resistor R1, a second resistor R2 and a third resistor R3 to form an operational unit, so that the output voltage Vout can be continuously adjusted according to the control value K.

[0042] As an optional embodiment, the operational unit includes: a second operational amplifier U2, a fourth resistor R4, and a fifth resistor R5; The output terminal of the second operational amplifier U2 is connected to the first terminal of the fourth resistor R4 and serves as the output terminal of the operational unit; the inverting input terminal of the second operational amplifier U2 is connected to the second terminal of the fourth resistor R4 and the first terminal of the fifth resistor R5; the second terminal of the fifth resistor R5 is grounded; the non-inverting input terminal of the second operational amplifier U2 serves as the input terminal of the operational unit.

[0043] Specifically, such as Figure 4 As shown, in this embodiment, the sampling module 2 adopts a voltage divider structure composed of the eighth resistor R8 and the ninth resistor R9; the digital adjustable proportional unit is implemented using a digital potentiometer; the arithmetic unit specifically includes a second operational amplifier U2, a fourth resistor R4, and a fifth resistor R5. The digital potentiometer is a 256-tap digital potentiometer, with the resistance between its high-side H and low-side L being Rhl, the resistance between its high-side H and common terminal W being Rhw, and the resistance between its low-side L and common terminal W being Rwl; the digital potentiometer internally divides the resistance into 256 equal parts, the control value K ranges from 0 to 255, and the resistance between the low-side L and common terminal W satisfies: ; Therefore, the feedback voltage V1 output from the common terminal W of the digital potentiometer and the output voltage Vu2_out of the second operational amplifier U2 satisfy: ; Further analysis of the input / output network of the second operational amplifier reveals the following: ; Therefore, the feedback voltage V1 output from the common terminal W of the digital potentiometer is: ; Because the power conversion module 1 adjusts V1 to Vfb, where Vfb is the reference voltage of the error amplifier inside the power converter control chip, the following relationship is obtained: ; That is, the output voltage Vout of power conversion module 1 is: ; As can be seen from the above formula, by changing the control value K, the output voltage Vout can be continuously and programmatically adjusted.

[0044] As can be seen, this embodiment uses the second operational amplifier U2, the fourth resistor R4 and the fifth resistor R5 to form an operational unit, and achieves adjustable output voltage Vout with a simple circuit structure.

[0045] As an optional embodiment, the voltage follower includes: Third operational amplifier U3, sixth resistor R6 and seventh resistor R7; The non-inverting input of the third operational amplifier U3 is connected to the first terminal of the sixth resistor R6; the second terminal of the sixth resistor R6 serves as the input of the voltage follower; the inverting input of the third operational amplifier U3 is connected to the first terminal of the seventh resistor R7; the second terminal of the seventh resistor R7 is connected to the output of the third operational amplifier U3 and serves as the output of the voltage follower.

[0046] Specifically, the signal output from the digitally adjustable proportional unit is first input to the voltage follower. The third operational amplifier U3 operates in voltage follower mode under negative feedback, causing the output voltage to follow changes in the input voltage, and then outputs this signal to the subsequent operational unit. Because the third operational amplifier U3 has a high input impedance and a low output impedance, it effectively reduces the impact of changes in the operational unit's input impedance on the output signal of the digitally adjustable proportional unit, while simultaneously improving the signal's driving capability.

[0047] As can be seen, compared with the digital adjustable proportional unit directly driving the arithmetic unit, this embodiment achieves buffer isolation between the digital adjustable proportional unit and the arithmetic unit by setting a voltage follower, which reduces the impact of the downstream load on the output signal of the digital adjustable proportional unit, improves the stability and driving capability of the signal, and thus improves the feedback regulation accuracy.

[0048] As an optional embodiment, the digital adjustable proportional unit is a digital potentiometer; the high-side terminal H of the digital potentiometer serves as the first input terminal of the digital adjustable proportional unit; the low-side terminal L of the digital potentiometer serves as the second input terminal of the digital adjustable proportional unit; the common terminal W of the digital potentiometer serves as the output terminal of the digital adjustable proportional unit; and the control terminal DIN of the digital potentiometer serves as the control terminal of the digital adjustable proportional unit.

[0049] Specifically, the digital potentiometer has multiple taps with fixed resistance ratios. The controller sends a control signal to the control terminal DIN of the digital potentiometer, and the digital potentiometer switches between different tap positions according to the control signal, thereby changing the output ratio corresponding to the common terminal W. The digital potentiometer is not used as a feedback voltage divider resistor in sampling module 2, but participates in the feedback adjustment process as a digitally adjustable proportional unit. Its output proportional signal works with the arithmetic unit to generate a feedback voltage V1. In practical applications, a filter capacitor C9 is placed between the power supply terminal and the ground terminal of the digital potentiometer. Therefore, the digital potentiometer does not need to withstand the main circuit voltage and main circuit current in the feedback voltage divider network, but operates under conditions of lower voltage and lower current.

[0050] As can be seen, compared with the solution of directly using a digital potentiometer to replace the feedback voltage divider resistor, this embodiment makes full use of the high proportional accuracy of the digital potentiometer, and realizes feedback regulation by controlling the proportional relationship, without relying on the absolute resistance accuracy of the digital potentiometer. This reduces the impact of temperature drift, withstand voltage and overcurrent capability on output accuracy, and improves the stability, consistency and reliability of feedback regulation.

[0051] As an optional embodiment, sampling module 2 includes: The eighth resistor R8 and the ninth resistor R9; The first end of the eighth resistor R8 serves as the input terminal of the sampling module 2; the second end of the eighth resistor R8 is connected to the first end of the ninth resistor R9; the second end of the ninth resistor R9 is grounded; the connection point between the eighth resistor R8 and the ninth resistor R9 serves as the output terminal of the sampling module 2. Specifically, the eighth resistor R8 and the ninth resistor R9 form a feedback voltage divider network. The output voltage Vout from the power conversion module 1 is input to the sampling module 2, where it is divided by the eighth resistor R8 and the ninth resistor R9. A sampling signal corresponding to the output voltage Vout is formed at the connection point of the two resistors and output to the feedback adjustment module 3. The feedback adjustment module 3 processes the sampling signal according to the control signal to generate a feedback voltage V1, which is then fed back to the power conversion module 1 to achieve closed-loop regulation of the output voltage Vout. Since the sampling module 2 is only responsible for establishing a stable correspondence between the output voltage Vout and the sampling signal, while the regulation of the output voltage Vout is completed by the feedback adjustment module 3, there is no need to change the resistance values ​​of the eighth resistor R8 and the ninth resistor R9, nor is it necessary to switch between different voltage divider networks during the adjustment of the output voltage Vout. The sampling module 2 maintains a fixed voltage division ratio, continuously providing a stable and accurate sampling signal.

[0052] As can be seen, compared to the traditional scheme that adjusts the output voltage Vout by changing the resistance value of the feedback voltage divider resistor, this embodiment makes the sampling function and the feedback adjustment function independent. The sampling module 2 maintains a fixed structure, and only the feedback adjustment module 3 changes the feedback voltage V1 to achieve program control of the output voltage Vout. Therefore, it not only avoids frequent replacement of the feedback voltage divider resistor or switching between different resistor networks, but also ensures the stability of the sampling ratio, improving the adjustment accuracy, long-term stability, and system reliability of the output voltage Vout.

[0053] To solve the above-mentioned technical problems, the present invention also provides a power management output regulation feedback control system, including a power supply, a controller, and the aforementioned power management output regulation feedback control circuit; the power supply is connected to the input terminal of the power conversion module 1; the output terminal of the controller is connected to the control terminal of the digital adjustable proportional unit, and is used to output a control signal to control the control value of the digital adjustable proportional unit.

[0054] For an introduction to the power management output regulation feedback control system provided by this invention, please refer to the embodiment of the power management output regulation feedback control circuit; this invention will not be described again here.

[0055] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0056] It should also be noted that, in this specification, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

Claims

1. A power management output regulation feedback control circuit, characterized in that, include: Power conversion module, sampling module, feedback regulation module; The output terminal of the power conversion module is connected to the input terminal of the sampling module, and the feedback terminal of the power conversion module is connected to the output terminal of the feedback adjustment module, which is used to adjust the output voltage of the output terminal according to the feedback voltage received by the feedback terminal. The sampling module is used to generate a sampling signal based on the output voltage; The feedback adjustment module is located between the output terminal of the sampling module and the feedback terminal of the power conversion module; the feedback adjustment module includes an arithmetic unit and a digitally adjustable proportional unit, which is used to change the correspondence between the output voltage and the feedback voltage by adjusting the control value of the digitally adjustable proportional unit to obtain the feedback voltage.

2. The power management output regulation feedback control circuit as described in claim 1, characterized in that, The first and second input terminals of the digital adjustable proportional unit are respectively connected to the reference voltage and ground. The control terminal of the digital adjustable proportional unit is used to receive control signals. The output terminal of the digital adjustable proportional unit is connected to the first input terminal of the arithmetic unit. The second input terminal of the arithmetic unit is used to receive sampling signals. The output terminal of the arithmetic unit is connected to the feedback terminal of the power conversion module.

3. The power management output regulation feedback control circuit as described in claim 1, characterized in that, The first and second input terminals of the digitally adjustable proportional unit are respectively connected to the output terminal of the arithmetic unit and ground. The control terminal of the digitally adjustable proportional unit is used to receive the control signal. The output terminal of the digitally adjustable proportional unit is connected to the feedback terminal of the power conversion module. The input terminal of the arithmetic unit is used to receive the sampling signal.

4. The power management output regulation feedback control circuit as described in claim 2, characterized in that, Also includes: A voltage follower, the input of which is connected to the output of the digitally adjustable proportional unit, and the output of which is connected to the first input of the arithmetic unit, is used to buffer and isolate the digitally adjustable proportional unit from the arithmetic unit.

5. The power management output regulation feedback control circuit as described in claim 2, characterized in that, The operational unit includes: a first operational amplifier, a first resistor, a second resistor, and a third resistor; The output terminal of the first operational amplifier is connected to the first terminal of the first resistor and serves as the output terminal of the operational unit; the inverting input terminal of the first operational amplifier is connected to the second terminal of the first resistor and the first terminal of the second resistor; the second terminal of the second resistor is grounded; the non-inverting input terminal of the first operational amplifier is connected to the first terminal of the third resistor and serves as the second input terminal of the operational unit; the second terminal of the third resistor serves as the first input terminal of the operational unit.

6. The power management output regulation feedback control circuit as described in claim 3, characterized in that, The operational unit includes: a second operational amplifier, a fourth resistor, and a fifth resistor; The output terminal of the second operational amplifier is connected to the first terminal of the fourth resistor and serves as the output terminal of the operational unit; the inverting input terminal of the second operational amplifier is connected to the second terminal of the fourth resistor and the first terminal of the fifth resistor; the second terminal of the fifth resistor is grounded; the non-inverting input terminal of the second operational amplifier serves as the input terminal of the operational unit.

7. The power management output regulation feedback control circuit as described in claim 4, characterized in that, The voltage follower includes: Third operational amplifier, sixth resistor, and seventh resistor; The non-inverting input of the third operational amplifier is connected to the first terminal of the sixth resistor; the second terminal of the sixth resistor serves as the input of the voltage follower; the inverting input of the third operational amplifier is connected to the first terminal of the seventh resistor; the second terminal of the seventh resistor is connected to the output of the third operational amplifier and serves as the output of the voltage follower.

8. The power management output regulation feedback control circuit as described in any one of claims 1 to 7, characterized in that, The digitally adjustable proportional unit is a digital potentiometer; the high end of the digital potentiometer serves as the first input terminal of the digitally adjustable proportional unit; the low end of the digital potentiometer serves as the second input terminal of the digitally adjustable proportional unit; the common terminal of the digital potentiometer serves as the output terminal of the digitally adjustable proportional unit; and the control terminal of the digital potentiometer serves as the control terminal of the digitally adjustable proportional unit.

9. The power management output regulation feedback control circuit as described in claim 8, characterized in that, The sampling module includes: The eighth and ninth resistors; The first end of the eighth resistor serves as the input terminal of the sampling module; the second end of the eighth resistor is connected to the first end of the ninth resistor; the second end of the ninth resistor is grounded; the connection node between the eighth resistor and the ninth resistor serves as the output terminal of the sampling module.

10. A power management output regulation feedback control system, comprising a power supply and a controller, characterized in that, It also includes a power management output regulation feedback control circuit as described in any one of claims 1 to 9; the power supply is connected to the input terminal of the power conversion module; the output terminal of the controller is connected to the control terminal of the digitally adjustable proportional unit, and is used to output a control signal to control the control value of the digitally adjustable proportional unit.

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