An output voltage compensation circuit and a compensation method

Abstract

An embodiment of the present invention discloses an output voltage compensation circuit and a compensation method. The circuit includes: a control module, a PWM output module, a power conversion module, a current detection module, a voltage compensation adjustment module, and a feedback module. Among them, the PWM output module is used to output a PWM signal to the power conversion module, and the power conversion module is used to convert the signal at the voltage input end according to the PWM signal output by the PWM output module and output it from the voltage output end. The current detection module is used to detect the current flowing through the power conversion module, and the voltage compensation adjustment module is used to output a compensation voltage to the feedback module according to the current detected by the current detection module and the voltage output by the power conversion module. The control module is used to adjust the PWM signal output by the PWM output module according to the compensation voltage output by the voltage compensation adjustment module so as to adjust the output voltage of the power conversion module. It is realized that the voltage drop caused by the wiring impedance can be compensated without remote feedback and without adding feedback lines, thereby reducing the wiring complexity and cost.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of electronic technologies, and in particular, to an output voltage compensation circuit and a compensation method. Background Art

[0002] During the process of the switching power supply outputting current, due to the equivalent resistance existing in the Printed Circuit Board (PCB) traces, the power supply voltage drop will occur during the process of the current transmitting from the power supply output terminal to the load terminal. Therefore, the feedback method is usually adopted to compensate for the voltage drop.

[0003] Currently, there are mainly three switching power supply feedback methods: proximal feedback, distal single-ended feedback, and distal differential feedback. Proximal feedback is used to supply power to units that are not sensitive to the power supply, and distal feedback is used to supply power to units that are sensitive to the power supply (for example, the central processing unit). The function of distal feedback is that the switching power supply compensates for the voltage drop caused by the PCB traces by collecting the voltage with voltage drop at the load terminal as feedback. Among them, single-ended feedback compensates for the voltage drop of the power supply positive trace, and differential feedback compensates for the voltage drops of the power supply positive and ground traces. However, in order to make the power supply more accurate, the distal feedback line needs to be connected out from inside the load chip (chip ball out). For complex multi-power systems (such as smart terminals like mobile phones), it will increase the trace cost and trace complexity. Summary of the Invention

[0004] The present invention provides an output voltage compensation circuit and a compensation method to achieve compensating for the voltage drop generated by the trace impedance without distal feedback and without adding feedback lines, thereby reducing the trace complexity and manufacturing cost.

[0005] In a first aspect, an embodiment of the present invention provides an output voltage compensation circuit, which includes: a control module, a PWM output module, a power conversion module, a current detection module, a voltage compensation adjustment module, and a feedback module;

[0006] Wherein, the control module is electrically connected to the PWM output module, the PWM output module is electrically connected to the power conversion module, the PWM output module is used to output a PWM signal to the power conversion module, and the power conversion module is used to convert the signal at the voltage input terminal according to the PWM signal output by the PWM output module and output it from the voltage output terminal;

[0007] The current detection module is electrically connected to the power conversion module and the voltage compensation and regulation module respectively. The voltage compensation and regulation module is electrically connected to the voltage output end of the power conversion module and the feedback module respectively. The feedback module is electrically connected to the current detection module and the control module respectively. Among them, the current detection module is used to detect the current flowing through the power conversion module, and the voltage compensation and regulation module is used to output a compensation voltage to the feedback module according to the current detected by the current detection module and the voltage output by the power conversion module;

[0008] Among them, the control module is used to adjust the PWM signal output by the PWM output module according to the compensation voltage output by the voltage compensation and regulation module to adjust the output voltage of the power conversion module.

[0009] In a second aspect, an embodiment of the present invention further provides a method for compensating an output voltage compensation circuit, which is characterized in that it is executed by an output voltage compensation circuit. The output voltage compensation circuit includes a control module, a PWM output module, a power conversion module, a current detection module, a voltage compensation and regulation module, and a feedback module. Among them, the control module is electrically connected to the PWM output module, the PWM output module is electrically connected to the power conversion module, and the PWM output module is used to output a PWM signal to the power conversion module. The power conversion module is used to convert the signal at the voltage input end and output it from the voltage output end according to the PWM signal output by the PWM output module. The current detection module is electrically connected to the power conversion module and the voltage compensation and regulation module respectively. The voltage compensation and regulation module is electrically connected to the voltage output end of the power conversion module and the feedback module respectively. The feedback module is electrically connected to the current detection module and the control module respectively. Among them, the current detection module is used to detect the current flowing through the power conversion module, and the voltage compensation and regulation module is used to output a compensation voltage to the feedback module according to the current detected by the current detection module and the voltage output by the power conversion module;

[0010] The compensation method includes: adjusting the PWM signal output by the PWM output module according to the compensation voltage output by the voltage compensation and regulation module to adjust the output voltage of the power conversion module.

[0011] The present invention provides an output voltage compensation circuit, which includes: a control module, a PWM output module, a power conversion module, a current detection module, a voltage compensation adjustment module, and a feedback module; wherein, the control module is electrically connected to the PWM output module, the PWM output module is electrically connected to the power conversion module, the PWM output module is used to output a PWM signal to the power conversion module, and the power conversion module is used to convert the signal at the voltage input end according to the PWM signal output by the PWM output module and output it from the voltage output end; the current detection module is respectively electrically connected to the power conversion module and the voltage compensation adjustment module, the voltage compensation adjustment module is respectively electrically connected to the voltage output end of the power conversion module and the feedback module, and the feedback module is respectively electrically connected to the current detection module and the control module; wherein, the current detection module is used to detect the current flowing through the power conversion module, and the voltage compensation adjustment module is used to output a compensation voltage to the feedback module according to the current detected by the current detection module and the voltage output by the power conversion module; wherein, the control module is used to adjust the PWM signal output by the PWM output module according to the compensation voltage output by the voltage compensation adjustment module so as to adjust the output voltage of the power conversion module. It can be seen that through this circuit, the problems of high wiring complexity and high wiring manufacturing cost existing in the existing compensation methods can be solved, and the voltage drop caused by wiring impedance can be compensated without remote feedback and without adding feedback lines, thereby reducing the wiring complexity and manufacturing cost. Description of the Drawings

[0012] Figure 1 is a schematic structural diagram of an output voltage compensation circuit in Embodiment 1 of the present invention;

[0013] Figure 2 is a schematic structural diagram of an output voltage compensation circuit in Embodiment 2 of the present invention;

[0014] Figure 3 is a schematic structural diagram of an output voltage compensation circuit in Embodiment 3 of the present invention;

[0015] Figure 4 is a flowchart of a compensation method for an output voltage compensation circuit in Embodiment 4 of the present invention. Detailed Embodiments

[0016] The present invention will be further described in detail below with reference to the drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present invention, rather than limiting the present invention. In addition, it should be noted that only parts related to the present invention rather than all structures are shown in the drawings for the convenience of description.

[0017] Embodiment 1

[0018] Figure 1 is a schematic structural diagram of an output voltage compensation circuit provided in Embodiment 1 of the present invention, referring toFigure 1 , the output voltage compensation circuit includes: a control module 10, a PWM output module 20, a power conversion module 30, a current detection module 40, a voltage compensation adjustment module 50, and a feedback module 60;

[0019] Among them, the control module 10 is electrically connected to the PWM output module 20, the PWM output module 20 is electrically connected to the power conversion module 30, the PWM output module 20 is used to output a PWM signal to the power conversion module 30, and the power conversion module 30 is used to convert the signal at the voltage input terminal according to the PWM signal output by the PWM output module 20 and output it from the voltage output terminal;

[0020] The current detection module 40 is respectively electrically connected to the power conversion module 30 and the voltage compensation adjustment module 50, the voltage compensation adjustment module 50 is respectively electrically connected to the voltage output terminal of the power conversion module 30 and the feedback module 60, and the feedback module 60 is respectively electrically connected to the current detection module 40 and the control module 10; Among them, the current detection module 40 is used to detect the current flowing through the power conversion module 30, and the voltage compensation adjustment module 50 is used to output a compensation voltage to the feedback module 60 according to the current detected by the current detection module 40 and the voltage output by the power conversion module 30;

[0021] Among them, the control module 10 is used to adjust the PWM signal output by the PWM output module 20 according to the compensation voltage output by the voltage compensation adjustment module 50 to adjust the output voltage of the power conversion module 30.

[0022] Among them, the control module 10 can be a control chip with a trigger function. The current detection module 40 can be a current source detection chip.

[0023] In the technical solution of this embodiment, the implementation process of the output voltage compensation circuit is as follows: Refer to Figure 1, the control module 10 controls the PWM output module 20 to output a PWM signal to the power conversion module 30, and controls the output of the power conversion module 30 through the PWM signal. Since there is a certain equivalent impedance in the power supply trace, a certain voltage drop will be generated when the voltage output by the power conversion module 30 passes through the power supply trace, resulting in the inability to ensure the voltage requirement at the load end. Therefore, in the embodiment of the present invention, the current detection module 40 detects the current flowing through the power conversion module 30, and outputs the detected current to the voltage compensation adjustment module 50. The voltage compensation adjustment module 50 adjusts and outputs a compensation voltage to the feedback module 60, and then the feedback module 60 outputs it to the control module 10. The control module 10 controls the PWM output module 20 to output a PWM signal according to the compensation voltage fed back by the feedback module 60 to adjust the output voltage of the power conversion module 30. Thus, by feeding back the compensation voltage output by the voltage compensation adjustment module 50 to the control module 10, the control module 10 adjusts the PWM signal output by the PWM output module 20 according to the compensation voltage to adjust the voltage output of the power conversion module 30, thereby compensating for the voltage drop generated by the power supply trace impedance in the output voltage of the power conversion module 30. Therefore, through the embodiment of the present invention, the problems of high trace complexity and high trace manufacturing cost existing in the existing compensation methods can be solved, and the voltage drop generated by the trace impedance can be compensated without remote feedback and without adding feedback lines, thereby reducing the trace complexity and manufacturing cost.

[0024] The embodiment of the present invention provides an output voltage compensation circuit, which includes: a control module, a PWM output module, a power conversion module, a current detection module, a voltage compensation adjustment module, and a feedback module; wherein, the control module is electrically connected to the PWM output module, the PWM output module is electrically connected to the power conversion module, the PWM output module is used to output a PWM signal to the power conversion module, and the power conversion module is used to convert the signal at the voltage input end and output it from the voltage output end according to the PWM signal output by the PWM output module; the current detection module is respectively electrically connected to the power conversion module and the voltage compensation adjustment module, the voltage compensation adjustment module is respectively electrically connected to the voltage output end of the power conversion module and the feedback module, and the feedback module is respectively electrically connected to the current detection module and the control module; wherein, the current detection module is used to detect the current flowing through the power conversion module, and the voltage compensation adjustment module is used to output a compensation voltage to the feedback module according to the current detected by the current detection module and the voltage output by the power conversion module; wherein, the control module is used to adjust the PWM signal output by the PWM output module according to the compensation voltage output by the voltage compensation adjustment module to adjust the output voltage of the power conversion module. It can be seen from this that through this circuit, the problems of high trace complexity and high trace manufacturing cost existing in the existing compensation methods can be solved, and the voltage drop generated by the trace impedance can be compensated without remote feedback and without adding feedback lines, thereby reducing the trace complexity and manufacturing cost.

[0025] Embodiment 2

[0026] Figure 2 FIG. is a schematic structural diagram of an output voltage compensation circuit provided in Embodiment 2 of the present invention. Based on the above Embodiment 1, with reference to Figure 2 , the power conversion module 30 includes a first transistor M1, a second transistor M2, a third transistor M3, and a first inductor L1. The control terminals of the first transistor M1 and the second transistor M2 are both electrically connected to the first output terminal of the PWM output module 20. The control terminal of the third transistor M3 is electrically connected to the second output terminal of the PWM output module 20. The first ends of the first transistor M1 and the second transistor M2 are both electrically connected to the voltage input terminal Vin. The second end of the first transistor M1 is electrically connected to the first end of the third transistor M3. The second end of the third transistor M3 is grounded. The second end of the second transistor M2 is respectively electrically connected to the second end of the first transistor M1 and the first end of the first inductor L1. The second end of the first inductor L1 is electrically connected to the voltage output terminal Vout;

[0027] Wherein, the first end of the second transistor M2 is further electrically connected to the current detection module 40, and the current detection module 40 is used to detect the current flowing from the voltage input terminal Vin into the second transistor M2.

[0028] Wherein, with reference to Figure 2 , the control module 10 can control the conduction or cutoff of the first transistor M1, the second transistor M2, and the third transistor M3 by controlling the PWM output module 20 to output a PWM signal, and further can control the voltage input from the voltage input terminal Vin to be output from the voltage output terminal Vout. Among them, the first transistor M1 and the second transistor M2 can be PMOS transistors, and the third transistor M3 can be an NMOS transistor.

[0029] Wherein, with reference to Figure 2 , the power conversion module 30 further includes an impedance element R3. The voltage input terminal Vin further includes a first capacitive element C1, and the voltage output terminal Vout further includes a second capacitive element C2. The first end of the first capacitive element C1 is electrically connected to the voltage input terminal Vin, and the second end is grounded. The first end of the second capacitive element C2 is electrically connected to the voltage output terminal Vout, and the second end is grounded. The first capacitive element C1 and the second capacitive element C2 are used for filtering.

[0030] Optionally, continue to refer to Figure 2, the voltage compensation and regulation module 50 includes a proportional control unit 51, an adder 52, and an output voltage regulation unit 53. The proportional control unit 51 is electrically connected to the current detection module 40 and the first input terminal of the adder 52 respectively. The output voltage regulation unit 53 is electrically connected to the voltage output terminal Vout of the power conversion module 30 and the second input terminal of the adder 52 respectively. The output terminal of the adder 52 is electrically connected to the feedback module 60;

[0031] Among them, the proportional control unit 51 is used to amplify the current detected by the current detection module 40 by a preset proportional amplification factor and then output it to the first input terminal of the adder 52. The output voltage regulation unit 53 is used to output the voltage output from the voltage output terminal Vout of the power conversion module 30 to the second input terminal of the adder 52 after voltage regulation through a resistor. The adder 52 is used to superimpose the voltages input to its first input terminal and second input terminal and then output them to the feedback module 60.

[0032] Among them, the voltage output after superimposing the voltages input to the first input terminal and the second input terminal of the adder 52 is the compensation voltage. The compensation voltage is output to the second input terminal of the feedback module 60 and compared with the reference voltage signal Vref input to the first input terminal of the feedback module 60, and then output to the control module 10. The control module 10 controls the PWM output module 20 to output a PWM signal according to the feedback compensation voltage to regulate the output voltage of the power conversion module 30, so as to compensate for the voltage drop caused by the power supply line impedance.

[0033] Among them, the proportional control unit 51 can be a proportional amplifier. By adjusting the preset proportional amplification factor of the proportional amplifier, the voltage output by the power conversion module 30 can be compensated. By adjusting the output voltage regulation unit 53, the voltage of the voltage output terminal Vout of the power conversion module 30 can be regulated. Optionally, the preset proportional amplification factor of the proportional control unit 51 can be configured by a separate digital control module (such as a single-chip microcomputer). The output voltage of the voltage output terminal Vout of the power conversion module 30 can also be regulated by adjusting the output voltage regulation unit through the digital control module.

[0034] Optionally, continue to refer to Figure 2 , the output voltage regulation unit 53 includes a first resistor R1 and a second resistor R2. The first end of the first resistor R1 is electrically connected to the voltage output terminal Vout. The second end of the first resistor R1 is electrically connected to the second input terminal of the adder 52 and the first end of the second resistor R2 respectively. The second end of the second resistor R2 is grounded.

[0035] Among them, the voltage output through the first resistor R1 is output to the second input terminal of the adder 52, and the voltage output by the proportional control unit 51 is output to the first input terminal of the adder 52. The voltage output by the adder 52 after superimposing the voltages input to its first input terminal and second input terminal is the compensated feedback voltage. The compensated feedback voltage is output to the control module 10 through the feedback module 60. The control module 10 controls the PWM output module 20 to output a PWM signal according to the compensated voltage of the feedback to adjust the output voltage of the power conversion module 30, thereby compensating for the voltage drop caused by the impedance of the power supply trace.

[0036] Optionally, the first resistor R1 is a variable resistor.

[0037] Among them, the resistance value of the first resistor can be configured through a separate digital control module (such as a single-chip microcomputer) to adjust the voltage of the voltage output terminal Vout of the power conversion module 30. In addition, the first resistor R1 can also be a slide rheostat.

[0038] Optionally, continuing to refer to Figure 2 the voltage compensation adjustment module 50 further includes a filtering unit 54, and the filtering unit 54 is electrically connected to the current detection module 40 and the proportional control unit 51 respectively.

[0039] Among them, the filtering unit 54 can be a low-pass filter.

[0040] Optionally, continuing to refer to Figure 2 the feedback module 60 includes an operational amplifier B1 and a comparator B2. The first input terminal of the operational amplifier B1 is connected to the reference voltage signal Vref. The second input terminal of the operational amplifier B1 is electrically connected to the voltage compensation adjustment module 50. The output terminal of the operational amplifier B1 is electrically connected to the first input terminal of the comparator B2. The second input terminal of the comparator B2 is electrically connected to the current detection module 40. The output terminal of the comparator B2 is electrically connected to the control module 10.

[0041] Among them, the operational amplifier B1 can be an error amplifier, which is used to perform error amplification on the compensated voltage output by the adder 52 and the reference voltage signal Vref. Among them, the reference voltage signal Vref is a bandgap reference source. The comparator B2 is used to output the compensated feedback voltage output by the operational amplifier B1 to the feedback terminal R of the control module 10. In addition, the feedback module 60 further includes a ramp compensation module Vramp, and the ramp compensation module Vramp is used to superimpose the current signal output by the current detection module 40 and the ramp signal output by the ramp compensation module Vramp and then output it to the positive electrode of the operational amplifier. Thus, the stability of the current signal can be improved through signal superposition compensation.

[0042] In the technical solution of this embodiment, the working principles of the voltage compensation adjustment module 50 and the feedback module 60 are: Refer toFigure 2 Assume that the average current input at the voltage input terminal Vin of the power conversion module 30 is Iin, the voltage output at the voltage output terminal Vout is Vo, the output average current is Io, the impedance of the PCB trace loop is R0, and the impedance of the power trace loop inside the load chip is R1. Then, the power supply voltage drop to be compensated is Io*(R0 + R1).

[0043] Since the current output by the current detection module 40 is proportional to the average current Iin input at the voltage input terminal Vin, and the proportionality coefficient is set as a, the voltage V1 output by the filtering unit 54 is:

[0044] V1 = a*Iin

[0045] Assume that the efficiency of the power supply is η. Among them, the efficiency η can be obtained through testing. Under the condition that the input and output are determined, η is related to the load and usually takes the maximum value. Then, the output average current Io can be calculated as:

[0046]

[0047] The voltage V2 output by the proportional control unit 51 is:

[0048] V2 = -Io*(R0 + R1)*Vref / Vo

[0049] Among them, Vref is the reference voltage input at the first input terminal of the operational amplifier B1.

[0050] Therefore, according to the above two equations of V1 and V2, the proportional amplification coefficient P of the proportional control unit 51 can be obtained as:

[0051]

[0052] Among them, R1, η, Vref, and a are determined by the chip itself and are fixed parameters of the chip. R0, Vo, and Vin are determined by the specific product and can be adjusted according to the actual usage situation. Among them, in order to ensure the stability of the system, a can take the minimum value under this chip process, the efficiency η of the power supply takes the maximum value under all loads, the impedance of the PCB trace loop is R0, and the impedance of the power trace loop inside the load chip is R1 can be obtained through simulation technology, and Vo can be adjusted by adjusting the output voltage adjustment unit 53.

[0053] Thus, during the compensation adjustment of the output voltage compensation circuit, the output voltage of the output voltage adjustment unit 53 can be adjusted by a separate digital control module (such as a single-chip microcomputer) to adjust the voltage of the voltage output terminal Vout of the power conversion module 30. The impedance R0 of the PCB trace loop and the impedance R1 of the power trace loop inside the load chip are obtained through simulation technology. According to parameters such as the voltage of the voltage output terminal Vout, the impedance R0 of the PCB trace loop, and the impedance R1 of the power trace loop inside the load chip, the preset proportional amplification factor of the proportional control unit 51 can be configured, so that the proportional control unit outputs the voltage value that the power conversion module 30 needs to compensate, and the voltage value to be compensated is fed back to the feedback terminal R of the control module 10 through the adder 52 and the feedback module 60. The control module 10 controls the PWM output module 20 to output a PWM signal according to the feedback signal to adjust the output voltage of the power conversion module 30.

[0054] Optionally, an overcurrent protection module 70 is further included, and the overcurrent protection module 70 is electrically connected to the current detection module 40 and the control module 10 respectively.

[0055] Among them, the overcurrent protection module 70 is electrically connected to the power conversion module 30, and is used to input the detected current of the power conversion module 30 to the overcurrent protection feedback terminal of the control module 10 to detect whether the power conversion module 30 has an overcurrent.

[0056] In addition, referring to Figure 2 , the output voltage compensation circuit further includes an overvoltage protection module OVP, a frequency configuration module PFM, and a signal source S. Among them, the overvoltage protection module OVP is used to protect the circuit when the circuit has an overvoltage, and the frequency configuration module PFM can configure the frequency of the control module 10, and the provided frequency is used when the power supply is lightly loaded.

[0057] Embodiment III

[0058] Figure 3 is a schematic structural diagram of an output voltage compensation circuit provided in Embodiment III of the present invention. On the basis of the above embodiment, referring to Figure 3 , the power conversion module 30 includes a fourth transistor M4, a fifth transistor M5, and a second inductor L2. The control end of the fourth transistor M4 is electrically connected to the first output end of the PWM output module 20. The first end of the fourth transistor M4 is electrically connected to the voltage input terminal Vin. The second end of the fourth transistor M4 is respectively electrically connected to the first end of the fifth transistor M5 and the first end of the second inductor L2. The control end of the fifth transistor M5 is electrically connected to the second output end of the PWM output module 20. The second end of the fifth transistor M5 is grounded. The second end of the second inductor L2 is electrically connected to the voltage output terminal Vout;

[0059] Among them, the first end and the second end of the second inductor L2 are respectively electrically connected to the current detection module 40, and the current detection module 40 is used to detect the current flowing into the second inductor L2.

[0060] Among them, the control module 10 can control the conduction or cut-off of the fourth transistor M4 and the fifth transistor M5 by controlling the PWM output module 20 to output a PWM signal, and further can control the voltage input from the voltage input terminal Vin to be output from the voltage output terminal Vout. Among them, the fourth transistor M4 can be a P-type MOS transistor, and the fifth transistor M5 can be an N-type MOS transistor.

[0061] In the technical solution of this embodiment, the working principles of the voltage compensation adjustment module 50 and the feedback module 60 are as follows: Refer to Figure 2 , assuming that the voltage output from the voltage output terminal Vout of the power conversion module 30 is Vo, the output average current is Io, the resistance of the first inductor L1 is RL, the impedance of the PCB trace loop is R0, and the impedance of the power trace loop inside the load chip is R1, then the power supply voltage drop to be compensated is Io*(R0 + R1).

[0062] Since the current output by the current detection module 40 is proportional to the average current Io at the voltage output terminal, and assuming the proportional coefficient is a, the voltage V1 output by the filtering unit 54 is:

[0063] V1 = a*Io*RL

[0064] The voltage V2 output by the proportional control unit 51 is:

[0065] V2 = -Io*(R0 + R1)*Vref / Vo

[0066] Among them, Vref is the reference voltage input to the first input terminal of the operational amplifier B1.

[0067] Thus, according to the above two expressions of V1 and V2, the proportional amplification coefficient P of the proportional control unit 51 can be obtained as:

[0068]

[0069] Among them, R1, Vref, and a are determined by the chip itself and are fixed parameters of the chip. R0, Vo, and RL are determined by the specific product and can be adjusted according to the actual usage situation. Among them, in order to ensure the stability of the system, a can take the minimum value under this chip process, RL can take the minimum value of the first inductor, the impedance of the PCB trace loop is R0 and the impedance of the power trace loop inside the load chip is R1 can be obtained through simulation technology, and Vo can be adjusted by adjusting the output voltage adjustment unit 53.

[0070] Therefore, during the compensation adjustment of the output voltage compensation circuit, the output voltage of the output voltage adjustment unit 53 can be adjusted by a separate digital control module (such as a single-chip microcomputer) to adjust the voltage of the voltage output terminal Vout of the power conversion module 30. The impedance R0 of the PCB trace loop and the impedance R1 of the power trace loop inside the load chip are obtained through simulation technology. According to parameters such as the voltage of the voltage output terminal Vout, the impedance R0 of the PCB trace loop, and the impedance R1 of the power trace loop inside the load chip, the preset proportional amplification factor of the proportional control unit 51 can be configured, so that the proportional control unit outputs the voltage value that the power conversion module 30 needs to compensate, and the voltage value to be compensated is fed back to the feedback terminal R of the control module 10 through the adder 52 and the feedback module 60. The control module 10 controls the PWM output module 20 to output a PWM signal according to the feedback signal to adjust the output voltage of the power conversion module 30.

[0071] Embodiment 4

[0072] Figure 4 FIG. 7 is a flowchart of a method for compensating an output voltage compensation circuit provided in Embodiment 4 of the present invention, which is executed by the output voltage compensation circuit. The output voltage compensation circuit includes a control module, a PWM output module, a power conversion module, a current detection module, a voltage compensation adjustment module, and a feedback module. Among them, the control module is electrically connected to the PWM output module, the PWM output module is electrically connected to the power conversion module, and the PWM output module is used to output a PWM signal to the power conversion module. The power conversion module is used to convert the signal at the voltage input terminal and output it from the voltage output terminal according to the PWM signal output by the PWM output module. The current detection module is electrically connected to the power conversion module and the voltage compensation adjustment module respectively, the voltage compensation adjustment module is electrically connected to the voltage output terminal of the power conversion module and the feedback module respectively, and the feedback module is electrically connected to the current detection module and the control module respectively. Among them, the current detection module is used to detect the current flowing through the power conversion module, and the voltage compensation adjustment module is used to output a compensation voltage to the feedback module according to the current detected by the current detection module and the voltage output by the power conversion module.

[0073] This embodiment is applicable to the implementation process of the output voltage compensation circuit. This method can be executed by the output voltage compensation circuit provided in any embodiment of the present invention. Refer to Figure 4 , and specifically includes the following steps:

[0074] Step 110: Adjust the PWM signal output by the PWM output module according to the compensation voltage output by the voltage compensation adjustment module to adjust the output voltage of the power conversion module.

[0075] In the technical solution of this embodiment, the current detection module detects the current flowing through the power conversion module, and outputs the detected current to the voltage compensation adjustment module. The voltage compensation adjustment module adjusts and outputs the compensation voltage to the feedback module, and then the feedback module outputs it to the control module. The control module controls the PWM output module to output a PWM signal according to the feedback signal of the feedback module to adjust the output voltage of the power conversion module. Thus, by feeding back the compensation voltage output by the voltage compensation adjustment module to the control module, the control module adjusts the PWM signal output by the PWM output module according to the compensation voltage to adjust the voltage output of the power conversion module, thereby compensating for the voltage drop caused by the impedance of the PCB trace, the internal power trace of the load chip, etc. of the power conversion module. Therefore, through the embodiments of the present invention, the problems of high wiring complexity and high wiring manufacturing cost existing in the existing compensation methods can be solved, and the voltage drop caused by the wiring impedance can be compensated without remote feedback and adding feedback lines, thereby reducing the wiring complexity and manufacturing cost.

[0076] Note that the above is only the preferred embodiment of the present invention and the technical principles applied. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described herein. Various obvious changes, re-adjustments and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in detail through the above embodiments, the present invention is not limited to the above embodiments. Without departing from the concept of the present invention, more other equivalent embodiments can be included, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. An output voltage compensation circuit, characterized in that, Comprising: A control module, a PWM output module, a power conversion module, a current detection module, a voltage compensation and regulation module, and a feedback module; Wherein, the control module is electrically connected to the PWM output module, the PWM output module is electrically connected to the power conversion module, the PWM output module is used to output a PWM signal to the power conversion module, and the power conversion module is used to convert the signal at the voltage input terminal according to the PWM signal output by the PWM output module and output it from the voltage output terminal; The current detection module is respectively electrically connected to the power conversion module and the voltage compensation and regulation module, the voltage compensation and regulation module is respectively electrically connected to the voltage output terminal of the power conversion module and the feedback module, and the feedback module is respectively electrically connected to the current detection module and the control module; wherein, the current detection module is used to detect the current flowing through the power conversion module, and the voltage compensation and regulation module is used to output a compensation voltage to the feedback module according to the current detected by the current detection module and the voltage output by the power conversion module; Wherein, the control module is used to adjust the PWM signal output by the PWM output module according to the compensation voltage output by the voltage compensation and regulation module to adjust the output voltage of the power conversion module; The voltage compensation and regulation module includes a proportional control unit, an adder, and an output voltage regulation unit. The proportional control unit is respectively electrically connected to the current detection module and the first input terminal of the adder, the output voltage regulation unit is respectively electrically connected to the voltage output terminal of the power conversion module and the second input terminal of the adder, and the output terminal of the adder is electrically connected to the feedback module; Wherein, the proportional control unit is used to adjust the current detected by the current detection module according to a preset proportional amplification factor and output it to the first input terminal of the adder, the output voltage regulation unit is used to adjust the voltage output from the voltage output terminal of the power conversion module and output it to the second input terminal of the adder, and the adder is used to superimpose the voltages input to its first input terminal and second input terminal and output them to the feedback module; The voltage compensation and regulation module further includes a filtering unit, and the filtering unit is respectively electrically connected to the current detection module and the proportional control unit.

2. The output voltage compensation circuit according to claim 1, characterized in that The power conversion module includes a first transistor, a second transistor, a third transistor, and a first inductor. The control terminals of the first transistor and the second transistor are both electrically connected to the first output terminal of the PWM output module, the control terminal of the third transistor is electrically connected to the second output terminal of the PWM output module, the first ends of the first transistor and the second transistor are both electrically connected to the voltage input terminal, the second end of the first transistor is electrically connected to the first end of the third transistor, the second end of the third transistor is grounded, the second end of the second transistor is respectively electrically connected to the second end of the first transistor and the first end of the first inductor, and the second end of the first inductor is electrically connected to the voltage output terminal; Wherein, the first end of the second transistor is also electrically connected to the current detection module, and the current detection module is configured to detect the current flowing from the voltage input terminal into the second transistor.

3. The output voltage compensation circuit according to claim 1, wherein The power conversion module includes a fourth transistor, a fifth transistor, and a second inductor. The control terminal of the fourth transistor is electrically connected to the first output terminal of the PWM output module. The first end of the fourth transistor is electrically connected to the voltage input terminal. The second end of the fourth transistor is respectively electrically connected to the first end of the fifth transistor and the first end of the second inductor. The control terminal of the fifth transistor is electrically connected to the second output terminal of the PWM output module. The second end of the fifth transistor is grounded. The second end of the second inductor is electrically connected to the voltage output terminal. Wherein, the first end and the second end of the second inductor are respectively electrically connected to the current detection module, and the current detection module is configured to detect the current flowing into the second inductor.

4. The output voltage compensation circuit according to claim 1, wherein The output voltage regulation unit includes a first resistor and a second resistor. The first end of the first resistor is electrically connected to the voltage output terminal. The second end of the first resistor is respectively electrically connected to the second input terminal of the adder and the first end of the second resistor. The second end of the second resistor is grounded.

5. The output voltage compensation circuit according to claim 4, wherein The first resistor is a variable resistor.

6. The output voltage compensation circuit according to claim 1, wherein The feedback module includes an operational amplifier and a comparator. The first input terminal of the operational amplifier is connected to a reference voltage signal. The second input terminal of the operational amplifier is electrically connected to the voltage compensation regulation module. The output terminal of the operational amplifier is electrically connected to the first input terminal of the comparator. The second input terminal of the comparator is electrically connected to the current detection module. The output terminal of the comparator is electrically connected to the control module.

7. The output voltage compensation circuit according to claim 1, wherein An overcurrent protection module is further included, and the overcurrent protection module is respectively electrically connected to the current detection module and the control module.

8. A method for compensating an output voltage of a compensation circuit, which is executed by the output voltage compensation circuit according to any one of claims 1-7, characterized in that, It is executed by an output voltage compensation circuit, and the output voltage compensation circuit includes a control module, a PWM output module, a power conversion module, a current detection module, a voltage compensation regulation module, and a feedback module. Wherein, the control module is electrically connected to the PWM output module, the PWM output module is electrically connected to the power conversion module, and the PWM output module is configured to output a PWM signal to the power conversion module. The power conversion module is configured to convert the signal at the voltage input terminal according to the PWM signal output by the PWM output module and output it from the voltage output terminal. The current detection module is respectively electrically connected to the power conversion module and the voltage compensation regulation module. The voltage compensation regulation module is respectively electrically connected to the voltage output terminal of the power conversion module and the feedback module. The feedback module is respectively electrically connected to the current detection module and the control module. Wherein, the current detection module is configured to detect the current flowing through the power conversion module, and the voltage compensation regulation module is configured to output a compensation voltage to the feedback module according to the current detected by the current detection module and the voltage output by the power conversion module. The compensation method includes: adjusting the PWM signal output by the PWM output module according to the compensation voltage output by the voltage compensation adjustment module to adjust the output voltage of the power conversion module.

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