CN114337190A - Output voltage compensation circuit and compensation method - Google Patents

Abstract

The embodiment of the invention discloses an output voltage compensation circuit and a compensation method, wherein the circuit comprises: the device comprises a control module, a PWM output module, a power conversion module, a current detection module, a voltage compensation regulation module and a feedback module; the power conversion module is used for converting a signal at a voltage input end according to the PWM signal output by the PWM output module and then outputting the converted signal from the voltage output end; the current detection module is used for detecting the current flowing through the power conversion module, and the voltage compensation adjustment module is used for outputting 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 for adjusting 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. The voltage drop generated by the wiring impedance can be compensated without remote feedback and increase of a feedback line, and the wiring complexity and cost are further reduced.

Description

Output voltage compensation circuit and compensation method

Technical Field

The embodiment of the invention relates to the technical field of electronics, in particular to an output voltage compensation circuit and a compensation method.

Background

In the process of outputting current by the switching power supply, because an equivalent resistor exists in a Printed Circuit Board (PCB) wiring, the voltage drop of the power supply can be caused in the process of transmitting current from the power output end to the load end, and therefore, the voltage drop can be compensated by adopting a feedback mode.

At present, the switching power supply mainly has three feedback modes, namely near-end feedback, far-end single-end feedback and far-end differential feedback. The near-end feedback is used to power the power-insensitive units and the far-end feedback is used to power the power-sensitive units (e.g., the central processor). The function of the far-end feedback is that the switching power supply compensates the voltage drop caused by the PCB wiring by collecting the voltage drop at the load end as the feedback, wherein the single-end feedback compensates the voltage drop of the power supply anode wiring, and the differential feedback compensates the wiring voltage drop of the power supply anode and the ground wiring. However, in order to make the power supply more accurate, the remote feedback line needs to be connected out from the inside of the load chip (chip out ball), and for a complex multi-power system (such as a smart terminal like a mobile phone), the wiring cost and the wiring complexity are increased.

Disclosure of Invention

The invention provides an output voltage compensation circuit and a compensation method, which can compensate voltage drop caused by wiring impedance without remote feedback and increase of a feedback line, thereby reducing wiring complexity and manufacturing cost.

In a first aspect, an embodiment of the present invention provides an output voltage compensation circuit, including: the device comprises a control module, a PWM output module, a power conversion module, a current detection module, a voltage compensation regulation module and a feedback module;

the control module is electrically connected with the PWM output module, the PWM output module is electrically connected with the power conversion module, the PWM output module is used for outputting PWM signals to the power conversion module, and the power conversion module is used for converting signals at a voltage input end according to the PWM signals output by the PWM output module and then outputting the converted signals from a voltage output end;

the current detection module is respectively and electrically connected with the power conversion module and the voltage compensation adjustment module, the voltage compensation adjustment module is respectively and electrically connected with the voltage output end of the power conversion module and the feedback module, and the feedback module is respectively and electrically connected with the current detection module and the control module; the current detection module is used for detecting the current flowing through the power conversion module, and the voltage compensation adjustment module is used for outputting 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 for adjusting the PWM signal output by the PWM output module according to the compensation voltage output by the voltage compensation adjusting module so as to adjust the output voltage of the power conversion module.

In a second aspect, an embodiment of the present invention further provides a compensation method for an output voltage compensation circuit, where the compensation method is performed by the 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 adjustment module, and a feedback module; the control module is electrically connected with the PWM output module, the PWM output module is electrically connected with the power conversion module, the PWM output module is used for outputting a PWM signal to the power conversion module, and the power conversion module is used for converting a signal at a voltage input end according to the PWM signal output by the PWM output module and then outputting the converted signal from a voltage output end; the current detection module is respectively and electrically connected with the power conversion module and the voltage compensation adjustment module, the voltage compensation adjustment module is respectively and electrically connected with the voltage output end of the power conversion module and the feedback module, and the feedback module is respectively and electrically connected with the current detection module and the control module; the current detection module is used for detecting the current flowing through the power conversion module, and the voltage compensation adjustment module is used for outputting 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 comprises the following steps: and adjusting the output voltage of the power conversion module according to the compensation voltage output by the voltage compensation adjustment module and the PWM signal output by the PWM output module.

The present invention provides an output voltage compensation circuit, including: the device comprises a control module, a PWM output module, a power conversion module, a current detection module, a voltage compensation regulation module and a feedback module; the power conversion module is used for converting a signal at a voltage input end according to the PWM signal output by the PWM output module and then outputting the converted signal from a voltage output end; the current detection module is respectively and electrically connected with the power conversion module and the voltage compensation adjustment module, the voltage compensation adjustment module is respectively and electrically connected with the voltage output end of the power conversion module and the feedback module, and the feedback module is respectively and electrically connected with the current detection module and the control module; the current detection module is used for detecting the current flowing through the power conversion module, and the voltage compensation adjustment module is used for outputting 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 for adjusting the PWM signal output by the PWM output module according to the compensation voltage output by the voltage compensation adjusting module so as to adjust the output voltage of the power conversion module. Therefore, the circuit can solve the problems of high wiring complexity and high wiring manufacturing cost of the conventional compensation method, can compensate the voltage drop caused by wiring impedance without remote feedback and increase of a feedback line, and further reduces the wiring complexity and the manufacturing cost.

Drawings

Fig. 1 is a schematic structural diagram of an output voltage compensation circuit according to a first embodiment of the present invention;

fig. 2 is a schematic structural diagram of an output voltage compensation circuit according to a second embodiment of the present invention;

fig. 3 is a schematic structural diagram of an output voltage compensation circuit according to a third embodiment of the present invention;

fig. 4 is a flowchart of a compensation method of an output voltage compensation circuit according to a fourth embodiment of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.

Example one

Fig. 1 is a schematic structural diagram of an output voltage compensation circuit according to a first embodiment of the present invention, and referring to fig. 1, the output voltage compensation circuit includes: the control module 10, the PWM output module 20, the power conversion module 30, the current detection module 40, the voltage compensation adjustment module 50, and the feedback module 60;

the control module 10 is electrically connected with the PWM output module 20, the PWM output module 20 is electrically connected with the power conversion module 30, the PWM output module 20 is configured to output a PWM signal to the power conversion module 30, and the power conversion module 30 is configured to convert a signal at a voltage input end according to the PWM signal output by the PWM output module 20 and then output the converted signal from a voltage output end;

the current detection module 40 is electrically connected with the power conversion module 30 and the voltage compensation adjustment module 50 respectively, the voltage compensation adjustment module 50 is electrically connected with the voltage output end of the power conversion module 30 and the feedback module 60 respectively, and the feedback module 60 is electrically connected with the current detection module 40 and the control module 10 respectively; the current detection module 40 is configured to detect a current flowing through the power conversion module 30, and the voltage compensation adjustment module 50 is configured to output a compensation voltage to the feedback module 60 according to the current detected by the current detection module 40 and a voltage output by the power conversion module 30;

the control module 10 is configured 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.

The control module 10 may be a control chip with a trigger function. The current detection module 40 may be a current source detection chip.

In the technical solution of this embodiment, the implementation process of the output voltage compensation circuit is as follows: referring to fig. 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. Because the power supply line has a certain equivalent impedance, the voltage output by the power conversion module 30 will generate a certain voltage drop through the power supply line, which results in that the voltage requirement at the load end cannot be ensured. Therefore, in the embodiment of the present invention, the current detecting module 40 detects the current flowing through the power conversion module 30, and outputs the detected current to the voltage compensation adjusting module 50, the voltage compensation adjusting module 50 adjusts the output compensation voltage to the feedback module 60, and the feedback module 60 outputs the adjusted output compensation voltage to the control module 10, and the control module 10 controls the PWM output module 20 to output the 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. Therefore, 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 of the voltage output by the power conversion module 30 due to the power trace impedance. Therefore, the embodiment of the invention can solve the problems of high wiring complexity and high wiring manufacturing cost of the existing compensation method, realize the compensation of voltage drop caused by wiring impedance without remote feedback and increase of a feedback line, and further reduce the wiring complexity and the manufacturing cost.

The embodiment of the invention provides an output voltage compensation circuit, which comprises: the device comprises a control module, a PWM output module, a power conversion module, a current detection module, a voltage compensation regulation module and a feedback module; the power conversion module is used for converting a signal at a voltage input end according to the PWM signal output by the PWM output module and then outputting the converted signal from a voltage output end; the current detection module is respectively and electrically connected with the power conversion module and the voltage compensation adjustment module, the voltage compensation adjustment module is respectively and electrically connected with the voltage output end of the power conversion module and the feedback module, and the feedback module is respectively and electrically connected with the current detection module and the control module; the current detection module is used for detecting the current flowing through the power conversion module, and the voltage compensation adjustment module is used for outputting 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 for adjusting the PWM signal output by the PWM output module according to the compensation voltage output by the voltage compensation adjusting module so as to adjust the output voltage of the power conversion module. Therefore, the circuit can solve the problems of high wiring complexity and high wiring manufacturing cost of the conventional compensation method, can compensate the voltage drop caused by wiring impedance without remote feedback and increase of a feedback line, and further reduces the wiring complexity and the manufacturing cost.

Example two

Fig. 2 is a schematic structural diagram of an output voltage compensation circuit provided in a second embodiment of the present invention, and referring to fig. 2, the power conversion module 30 includes a first transistor M1, a second transistor M2, a third transistor M3, and a first inductor L1, a control terminal of the first transistor M1 and a control terminal of the second transistor M2 are electrically connected to a first output terminal of the PWM output module 20, a control terminal of the third transistor M3 is electrically connected to a second output terminal of the PWM output module 20, a first terminal of the first transistor M1 and a first terminal of the second transistor M2 are electrically connected to a voltage input terminal Vin, a second terminal of the first transistor M1 is electrically connected to a first terminal of the third transistor M3, a second terminal of the third transistor M3 is grounded, a second terminal of the second transistor M2 is electrically connected to a second terminal of the first transistor M1 and a first terminal of the first inductor L1, the second end of the first inductor L1 is electrically connected to the voltage output terminal Vout;

the first end of the second transistor M2 is also electrically connected to the current detection module 40, and the current detection module 40 is configured to detect a current flowing from the voltage input terminal Vin into the second transistor M2.

Referring to fig. 2, the control module 10 may control the first transistor M1, the second transistor M2, and the third transistor M3 to be turned on or off by controlling the PWM output module 20 to output the PWM signal, so as to control the voltage input from the voltage input terminal Vin to be output from the voltage output terminal Vout. The first transistor M1 and the second transistor M2 may be PMOS transistors, and the third transistor M3 may be NMOS transistors.

Wherein, referring to fig. 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 capacitive element C1 has a first terminal electrically connected to the voltage input terminal Vin and a second terminal grounded. The second capacitive element C2 has a first terminal electrically connected to the voltage output terminal Vout and a second terminal grounded. The first capacitive element C1 and the second capacitive element C2 are used for filtering.

Alternatively, with continued reference to fig. 2, the voltage compensation adjustment module 50 includes a proportional control unit 51, an adder 52 and an output voltage adjustment unit 53, the proportional control unit 51 is electrically connected to the first input terminals of the current detection module 40 and the adder 52, respectively, the output voltage adjustment 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, and the output terminal of the adder 52 is electrically connected to the feedback module 60;

the proportional control unit 51 is configured to amplify the current detected by the current detection module 40 by a preset proportional amplification factor and output the amplified current to a first input end of the adder 52, the output voltage adjustment unit 53 is configured to output a voltage output by the voltage output end Vout of the power conversion module 30 to a second input end of the adder 52 after being adjusted by a resistor, and the adder 52 is configured to output a voltage input by the first input end and the second input end of the adder after being superimposed to the feedback module 60.

The voltage output by the adder 52 after the voltage input by the first input end and the voltage input by the second input end are superimposed is a compensation voltage, the compensation voltage is output to the second input end of the feedback module 60, and is output to the control module 10 after being compared with the reference voltage signal Vref input by the first input end of the feedback module 60, and the control module 10 controls the PWM output module 20 to output a PWM signal according to the feedback compensation voltage to adjust the output voltage of the power conversion module 30, so as to compensate the voltage drop generated by the power trace impedance.

Wherein the proportional control unit 51 may be a proportional amplifier. The voltage output by the power conversion module 30 can be compensated by adjusting the preset scaling factor of the scaling amplifier. The voltage of the voltage output terminal Vout of the power conversion module 30 can be adjusted by adjusting the output voltage adjusting unit 53. Alternatively, the preset scaling factor of the proportional control unit 51 may be configured by a separate digital control module (e.g., a single chip microcomputer). The output voltage regulating unit may also be regulated by the digital control module to regulate the output voltage of the voltage output terminal Vout of the power conversion module 30.

Alternatively, with continued reference to fig. 2, the output voltage adjusting unit 53 includes a first resistor R1 and a second resistor R2, a first end of the first resistor R1 is electrically connected to the voltage output terminal Vout, a 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, and a second end of the second resistor R2 is grounded.

The voltage output via 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 adder 52 adds the voltages input by the first input terminal and the second input terminal to output a voltage, which is the compensated feedback voltage, the compensated feedback voltage is output to the control module 10 through the feedback module 60, and the control module 10 controls the PWM output module 20 to output a PWM signal according to the fed compensated voltage to adjust the output voltage of the power conversion module 30, so as to compensate the voltage drop caused by the power trace impedance.

Optionally, the first resistor R1 is a variable resistor.

The resistance of the first resistor may be configured by a separate digital control module (e.g., a single chip) to regulate the voltage of the voltage output terminal Vout of the power conversion module 30. In addition, the first resistor R1 may be a sliding rheostat.

Optionally, with continued reference to fig. 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.

The filtering unit 54 may be a low-pass filter.

Optionally, with continued reference to fig. 2, the feedback module 60 includes an operational amplifier B1 and a comparator B2, a first input terminal of the operational amplifier B1 is connected to the reference voltage signal Vref, a second input terminal of the operational amplifier B1 is electrically connected to the voltage compensation adjustment module 50, an output terminal of the operational amplifier B1 is electrically connected to a first input terminal of the comparator B2, a second input terminal of the comparator B2 is electrically connected to the current detection module 40, and an output terminal of the comparator B2 is electrically connected to the control module 10.

The operational amplifier B1 may be an error amplifier, and is configured to perform error amplification on the compensation voltage output by the output terminal of the adder 52 and the reference voltage signal Vref. Wherein, the reference voltage signal Vref is a band-gap reference source. The comparator B2 is used to output the compensated feedback voltage output by the amplifier 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 configured to superimpose the current signal output by the current detection module 40 and a ramp signal output by the ramp compensation module Vramp and output the superimposed signal to the positive electrode of the operational amplifier, so that the stability of the current signal can be improved through signal superimposition compensation.

In the technical solution of this embodiment, the working principle of the voltage compensation adjustment module 50 and the feedback module 60 is as follows: referring to fig. 2, assuming that the average current input to the voltage input terminal Vin of the power conversion module 30 is Iin, the voltage output from 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, the power voltage drop to be compensated is Io (R0+ R1).

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 proportional coefficient is a, the voltage V1 output by the filtering unit 54 is:

V1＝a*Iin

assuming that the efficiency of the power supply is η, where the efficiency η can be obtained through testing, and in the case of a determined input and output, η is related to the load, and is usually taken as a maximum value, the output average current Io can be calculated as:

the voltage V2 output by the proportional control unit 51 is:

V2＝-Io*(R0+R1)*Vref/Vo

wherein Vref is the reference voltage inputted from the first input terminal of the operational amplifier B1.

Thus, according to the above two equations V1 and V2, the scaling factor P of the scaling control unit 51 can be obtained as:

wherein, R1, η, Vref, a are determined by the chip itself and are fixed parameters of the chip. R0, Vo and Vin are determined by specific products and can be adjusted according to actual use conditions. In order to ensure the stability of the system, a may be the minimum value in the chip process, the efficiency η of the power supply may be the maximum value in all loads, the impedance of the PCB routing loop is R0, and the impedance of the power supply routing loop inside the load chip is R1, which may be obtained by a simulation technique, and Vo may be adjusted by adjusting the output voltage adjusting unit 53.

Therefore, in the process of compensating and adjusting the output voltage compensation circuit, the output voltage of the output voltage adjusting 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 by simulation technology, the preset scaling factor of the scaling control unit 51 can be configured according to the voltage of the voltage output terminal Vout, the impedance R0 of the PCB trace loop, the impedance R1 of the power trace loop inside the load chip, and other parameters, therefore, the proportional control unit outputs the voltage value to be compensated of the power conversion module 30, and the voltage value to be compensated is fed back to the feedback end R of the control module 10 through the adder 52 and the feedback module 60, and the control module 10 controls the PWM output module 20 to output the PWM signal according to the feedback signal to adjust the output voltage of the power conversion module 30.

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.

The overcurrent protection module 70 is electrically connected to the power conversion module 30, and is configured to input the detected current of the power conversion module 30 to the overcurrent protection feedback terminal of the control module 10, so as to detect whether the power conversion module 30 is overcurrent.

In addition, referring to fig. 2, the output voltage compensation circuit further includes an overvoltage protection module OVP, a frequency configuration module PFM, and a signal source S. The overvoltage protection module OVP is used for protecting the circuit when the circuit is in 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 in light load.

EXAMPLE III

Fig. 3 is a schematic structural diagram of an output voltage compensation circuit provided in the third embodiment of the present invention, and referring to fig. 3, the power conversion module 30 includes a fourth transistor M4, a fifth transistor M5, and a second inductor L2, a control terminal of the fourth transistor M4 is electrically connected to the first output terminal of the PWM output module 20, a first terminal of the fourth transistor M4 is electrically connected to the voltage input terminal Vin, a second terminal of the fourth transistor M4 is electrically connected to the first terminal of the fifth transistor M5 and the first terminal of the second inductor L2, a control terminal of the fifth transistor M5 is electrically connected to the second output terminal of the PWM output module 20, a second terminal of the fifth transistor M5 is grounded, and a second terminal of the second inductor L2 is electrically connected to the voltage output terminal Vout;

the first end and the second end of the second inductor L2 are electrically connected to the current detection module 40, and the current detection module 40 is configured to detect a current flowing in the second inductor L2.

The control module 10 may control the fourth transistor M4 and the fifth transistor M5 to be turned on or off by controlling the PWM output module 20 to output the PWM signal, so as to control the voltage input from the voltage input terminal Vin to be output from the voltage output terminal Vout. The fourth transistor M4 may be a P-type MOS transistor, and the fifth transistor M5 may be an N-type MOS transistor.

In the technical solution of this embodiment, the working principle of the voltage compensation adjustment module 50 and the feedback module 60 is as follows: referring to fig. 2, assuming that the voltage output by 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, the power voltage drop to be compensated is Io (R0+ R1).

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

V1＝a*Io*RL

the voltage V2 output by the proportional control unit 51 is:

V2＝-Io*(R0+R1)*Vref/Vo

wherein Vref is the reference voltage inputted from the first input terminal of the operational amplifier B1.

Thus, according to the above two equations V1 and V2, the scaling factor P of the scaling control unit 51 can be obtained as:

wherein, R1, Vref, a are determined by the chip itself and are fixed parameters of the chip. R0, Vo and RL are determined by specific products and can be adjusted according to actual use conditions. In order to ensure the stability of the system, a may be the minimum value of the chip process, RL may be the minimum value of the first inductor, the impedance of the PCB routing loop is R0, and the impedance of the power routing loop inside the load chip is R1, which may be obtained by a simulation technique, and Vo may be adjusted by adjusting the output voltage adjusting unit 53.

Therefore, in the process of compensating and adjusting the output voltage compensation circuit, the output voltage of the output voltage adjusting unit 53 can be adjusted by a separate digital control module (such as a single chip) 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 by simulation technology, the preset scaling factor of the scaling control unit 51 can be configured according to the voltage of the voltage output terminal Vout, the impedance R0 of the PCB trace loop, the impedance R1 of the power trace loop inside the load chip, and other parameters, therefore, the proportional control unit outputs the voltage value to be compensated of the power conversion module 30, and the voltage value to be compensated is fed back to the feedback end R of the control module 10 through the adder 52 and the feedback module 60, and the control module 10 controls the PWM output module 20 to output the PWM signal according to the feedback signal to adjust the output voltage of the power conversion module 30.

Example four

Fig. 4 is a flowchart of a compensation method of an output voltage compensation circuit according to a fourth embodiment of the present invention, which is executed by the output voltage compensation circuit, where 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; the power conversion module is used for converting a signal at a voltage input end according to the PWM signal output by the PWM output module and then outputting the converted signal from a voltage output end; the current detection module is respectively and electrically connected with the power conversion module and the voltage compensation adjustment module, the voltage compensation adjustment module is respectively and electrically connected with the voltage output end of the power conversion module and the feedback module, and the feedback module is respectively and electrically connected with the current detection module and the control module; the current detection module is used for detecting the current flowing through the power conversion module, and the voltage compensation adjustment module is used for outputting 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 present embodiment is applicable to an implementation process of an output voltage compensation circuit, and the method may be executed by the output voltage compensation circuit provided in any embodiment of the present invention, and with reference to fig. 4, specifically includes the following steps:

and step 110, adjusting the output voltage of the power conversion module according to the compensation voltage output by the voltage compensation adjustment module and the PWM signal output by the PWM output module.

In the technical scheme of this implementation, 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 the output compensation voltage to the feedback module, and then the feedback module outputs the compensation voltage to the control module, and the control module controls the PWM output module to output the PWM signal according to the feedback signal of the feedback module to adjust the output voltage of the power conversion module. Therefore, the compensation voltage output by the voltage compensation adjusting module is fed back to the control module, and the control module adjusts the PWM signal output by the PWM output module according to the compensation voltage so as to adjust the voltage output of the power conversion module, thereby compensating the voltage drop of the power conversion module caused by impedance such as PCB wiring, power supply wiring in a load chip and the like. Therefore, the embodiment of the invention can solve the problems of high wiring complexity and high wiring manufacturing cost of the existing compensation method, and can compensate the voltage drop generated by wiring impedance without remote feedback and feedback line increase, thereby reducing the wiring complexity and manufacturing cost.

It is to be noted that the foregoing is only illustrative of the preferred embodiments of the present invention and the technical principles employed. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.

Claims (10)

1. An output voltage compensation circuit, comprising: the device comprises a control module, a PWM output module, a power conversion module, a current detection module, a voltage compensation regulation module and a feedback module;

the control module is electrically connected with the PWM output module, the PWM output module is electrically connected with the power conversion module, the PWM output module is used for outputting a PWM signal to the power conversion module, and the power conversion module is used for converting a signal at a voltage input end according to the PWM signal output by the PWM output module and then outputting the converted signal from a voltage output end;

the current detection module is respectively and electrically connected with the power conversion module and the voltage compensation adjustment module, the voltage compensation adjustment module is respectively and electrically connected with the voltage output end of the power conversion module and the feedback module, and the feedback module is respectively and electrically connected with the current detection module and the control module; the current detection module is used for detecting the current flowing through the power conversion module, and the voltage compensation adjustment module is used for outputting 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 for adjusting the PWM signal output by the PWM output module according to the compensation voltage output by the voltage compensation adjusting module so as to adjust the output voltage of the power conversion module.

2. The output voltage compensation circuit of claim 1, wherein the power conversion module comprises a first transistor, a second transistor, a third transistor, and a first inductor, the control end of the first transistor and the control end of the second transistor are both electrically connected with the first output end of the PWM output module, a control terminal of the third transistor is electrically connected with the second output terminal of the PWM output module, a first terminal of the first transistor and a first terminal of the second transistor are both electrically connected to the voltage input terminal, a second terminal of the first transistor is electrically connected to a first terminal of the third transistor, a second terminal of the third transistor is grounded, a second end of the second transistor is electrically connected with a second end of the first transistor and a first end of the first inductor respectively, and a second end of the first inductor is electrically connected with the voltage output end;

the first end of the second transistor is electrically connected to the current detection module, and the current detection module is configured to detect a current flowing into the second transistor from the voltage input end.

3. The output voltage compensation circuit of claim 1, wherein the power conversion module comprises a fourth transistor, a fifth transistor and a second inductor, a control terminal of the fourth transistor is electrically connected to the first output terminal of the PWM output module, a first terminal of the fourth transistor is electrically connected to the voltage input terminal, a second terminal of the fourth transistor is electrically connected to the first terminal of the fifth transistor and the first terminal of the second inductor, respectively, a control terminal of the fifth transistor is electrically connected to the second output terminal of the PWM output module, a second terminal of the fifth transistor is grounded, and a second terminal of the second inductor is electrically connected to the voltage output terminal;

the first end and the second end of the second inductor are respectively electrically connected with the current detection module, and the current detection module is used for detecting current flowing into the second inductor.

4. The output voltage compensation circuit of claim 1, wherein the voltage compensation adjustment module comprises a proportional control unit, an adder and an output voltage adjustment unit, the proportional control unit is electrically connected to the current detection module and a first input terminal of the adder respectively, the output voltage adjustment unit is electrically connected to a voltage output terminal of the power conversion module and a second input terminal of the adder respectively, and an output terminal of the adder is electrically connected to the feedback module;

the proportional control unit is configured to adjust the current detected by the current detection module according to a preset proportional amplification factor and output the current to a first input end of the adder, the output voltage adjustment unit is configured to adjust the voltage output by the voltage output end of the power conversion module and output the voltage to a second input end of the adder, and the adder is configured to superimpose the voltages input by the first input end and the second input end of the adder and output the voltage to the feedback module.

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

6. The output voltage compensation circuit of claim 5, wherein the first resistor is a variable resistor.

7. The output voltage compensation circuit of claim 4, wherein the voltage compensation adjustment module further comprises a filtering unit electrically connected to the current detection module and the proportional control unit, respectively.

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

9. The output voltage compensation circuit of claim 1, further comprising an over-current protection module electrically connected to the current detection module and the control module, respectively.

10. The output voltage compensation circuit compensation method is characterized by being executed by an output voltage compensation circuit, wherein the output voltage compensation circuit comprises a control module, a PWM output module, a power conversion module, a current detection module, a voltage compensation regulation module and a feedback module; the control module is electrically connected with the PWM output module, the PWM output module is electrically connected with the power conversion module, the PWM output module is used for outputting a PWM signal to the power conversion module, and the power conversion module is used for converting a signal at a voltage input end according to the PWM signal output by the PWM output module and then outputting the converted signal from a voltage output end; the current detection module is respectively and electrically connected with the power conversion module and the voltage compensation adjustment module, the voltage compensation adjustment module is respectively and electrically connected with the voltage output end of the power conversion module and the feedback module, and the feedback module is respectively and electrically connected with the current detection module and the control module; the current detection module is used for detecting the current flowing through the power conversion module, and the voltage compensation adjustment module is used for outputting 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 comprises the following steps: and adjusting the output voltage of the power conversion module according to the compensation voltage output by the voltage compensation adjustment module and the PWM signal output by the PWM output module.

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