Maximum pulse width limiting circuit for driving and power factor correction circuit

Abstract

The utility model relates to a maximum pulse width limiting circuit for driving. The maximum pulse width limiting circuit comprises a signal protection module, a pulse width control module and an optocoupler driving module, wherein the signal protection module is used for stabilizing a received initial pulse signal; the pulse width control module is connected with the signal protection module and is used for adjusting the pulse width of the initial pulse signal so as to output a target pulse signal comprising a target duty ratio; and the optocoupler driving module is connected with the pulse width control module and is used for outputting a driving signal under the condition that the target pulse signal is received so as to control a to-be-driven circuit such as a boost inductor to work according to a target duty ratio, so that saturation of the boost inductor is avoided.

Description

Technical Field

[0001] The present application relates to the technical field of drive control, and in particular to a maximum pulse width limiting circuit for driving. Background Art

[0002] With the development of welding power supply technology, welding machines need to adapt to the working requirements of various input grid voltages. Therefore, the input voltage range of welding machines is relatively wide, usually working up to single three-phase 220V-575V, and the bus voltage can be as high as 840V after boosting.

[0003] However, when the welding machine is working under low grid voltage power supply conditions such as 220V, the boost inductor works at the maximum duty cycle, resulting in inductor saturation, which affects the working efficiency of the welding machine. Therefore, how to avoid saturation of the boost inductor has become one of the technical problems that need to be solved urgently. Utility Model Content

[0004] Based on this, it is necessary to provide a driving maximum pulse width limiting circuit that can avoid saturation of the boost inductor.

[0005] In a first aspect, the present application provides a maximum pulse width limiting circuit for driving, comprising:

[0006] Signal protection module, used to stabilize the received initial pulse signal;

[0007] a pulse width control module, connected to the signal protection module, and used to adjust the pulse width of the initial pulse signal to output a target pulse signal including a target duty cycle;

[0008] The optical coupling driving module is connected to the pulse width control module, and is used for outputting a driving signal when receiving the target pulse signal.

[0009] In one embodiment, the pulse width control module includes: a pulse width adjustment component, an impedance adjustment component, a switch component, a first voltage divider component and a second voltage divider component; wherein, the input end of the pulse width adjustment component is connected to the signal protection module, the output end of the pulse width adjustment component is connected to the first end of the impedance adjustment component, the second end of the impedance adjustment component is connected to the control end of the switch component, the first end of the switch component is respectively connected to the first end of the first voltage divider component, the optocoupler drive module, and the first end of the second voltage divider component, the second end of the first voltage divider component is connected to the signal protection module, and the second end of the switch component is respectively connected to the second end of the second voltage divider component, the common ground end, and the optocoupler drive module.

[0010] In one embodiment, the pulse width modulation component includes: a first diode, a first resistor, a second resistor, a first capacitor, a second capacitor and a pulse generating chip; wherein the positive electrode of the first diode is respectively connected to the signal protection module, the input end of the pulse generating chip, and the first end of the first resistor, the negative electrode of the first diode is respectively connected to the second end of the first resistor, the enable end of the pulse generating chip, and the first power supply, the first end of the second resistor is respectively connected to the first power supply and the first end of the first capacitor, the second end of the second resistor is respectively connected to the control end of the pulse generating chip and the first end of the second capacitor, and the second end of the first capacitor is respectively connected to the second end of the second capacitor and the common ground.

[0011] In one embodiment, the impedance adjustment component includes: a third resistor and a third capacitor; wherein the first end of the third resistor is respectively connected to the output end of the pulse generating chip and the first end of the third capacitor, and the second end of the third resistor is respectively connected to the second end of the third capacitor and the control end of the switch component.

[0012] In one embodiment, the switch component includes a transistor, the gate of the transistor is connected to the second end of the impedance adjustment component, the drain of the transistor is connected to the first end of the first voltage divider component, and the source of the transistor is connected to the common ground terminal; and / or,

[0013] The first voltage dividing component includes a fourth resistor; and / or,

[0014] The second voltage dividing component includes a fifth resistor.

[0015] In one embodiment, the optical coupling driving module includes:

[0016] A photoelectric coupler, the primary side of which is connected to the pulse width control module, and is used to output a switch control signal when receiving the target pulse signal;

[0017] A driving transistor, wherein the control end of the driving transistor is connected to the secondary side of the photocoupler, the first end of the driving transistor is respectively connected to the first power supply and the secondary side of the photocoupler, and the second end of the driving transistor is connected to the circuit to be driven, for outputting the driving signal when receiving the switch control signal.

[0018] In one embodiment, the optical coupling driving module further includes:

[0019] A discharge transistor, wherein the control end of the discharge transistor is connected to the secondary side of the photocoupler, the first end of the discharge transistor is respectively connected to the first end of the drive transistor and the circuit to be driven, and the second end of the discharge transistor is connected to a common ground end.

[0020] In one embodiment, the signal protection module includes:

[0021] A limiting circuit, used for performing a limiting process on the initial pulse signal when the initial pulse signal is received;

[0022] The capacitive-resistance circuit is connected to the amplitude limiting circuit and the pulse width control module respectively, and is used for buffering the initial pulse signal when the initial pulse signal is received.

[0023] In one embodiment, the limiting circuit includes: a second diode and a third diode; wherein the anode of the second diode is connected to the cathode of the third diode and the capacitive resistor circuit respectively, the cathode of the second diode is connected to the second power supply, and the anode of the third diode is connected to the common ground.

[0024] In a second aspect, the present application also provides a power factor correction circuit, which includes a maximum pulse width limiting circuit for driving and a circuit to be driven as described in any one of the embodiments; wherein the maximum pulse width limiting circuit for driving is connected to the circuit to be driven.

[0025] The maximum pulse width limiting circuit for driving of the present application includes: a signal protection module, a pulse width control module and an optocoupler driving module; wherein the signal protection module is used to stabilize the received initial pulse signal; the pulse width control module is connected to the signal protection module, and is used to adjust the pulse width of the initial pulse signal to output a target pulse signal including a target duty cycle; the optocoupler driving module is connected to the pulse width control module, and is used to output a driving signal when receiving a target pulse signal. The present application stabilizes the initial pulse signal through the signal protection module, improves the stability of the initial pulse signal, and thereby ensures the accuracy of the driving signal output by the maximum pulse width limiting circuit for driving, and then adjusts the pulse width of the initial pulse signal through the pulse width control module, outputs a target pulse signal including a target duty cycle, isolates the signal through the optocoupler driving module, avoids high voltage damage to the maximum pulse width limiting circuit for driving, and outputs a driving signal when receiving a target pulse signal, so as to control the circuit to be driven, such as a boost inductor, to work according to the target duty cycle, thereby avoiding saturation of the boost inductor. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the conventional technology, the drawings required for use in the embodiments or the conventional technology descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0027] Figure 1 A schematic diagram of the structure of a maximum pulse width limiting circuit for driving according to an embodiment;

[0028] Figure 2 A schematic diagram of the structure of a maximum pulse width limiting circuit for driving according to another embodiment;

[0029] Figure 3 FIG. 4 is a schematic diagram of the structure of a maximum pulse width limiting circuit for driving according to another embodiment.

[0030] Description of reference numerals:

[0031] 10. Signal protection module; 20. Pulse width control module; 210. Pulse width adjustment component; 220. Impedance adjustment component; 230. Switch component; 240. First voltage divider component; 250. Second voltage divider component; 30. Optocoupler drive module. DETAILED DESCRIPTION

[0032] In order to facilitate understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. Embodiments of the present application are provided in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0034] It is understood that the terms "first", "second", etc. used in this application may be used herein to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish a first element from another element. For example, without departing from the scope of this application, a first resistor may be referred to as a second resistor, and similarly, a second resistor may be referred to as a first resistor. Both the first resistor and the second resistor are resistors, but they are not the same resistor.

[0035] It can be understood that the “connection” in the following embodiments should be understood as “electrical connection”, “communication connection”, etc. if the connected circuits, modules, units, etc. have electrical signals or data transmission between each other.

[0036] It can be understood that “at least one” means one or more, “plurality” means two or more, and “at least a portion of an element” means a part or all of an element.

[0037] When used herein, the singular forms "a", "an", and "said / the" may also include plural forms, unless the context clearly indicates otherwise. It should also be understood that the terms "include / comprise" or "have" and the like specify the presence of stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not exclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. At the same time, the term "and / or" used in this specification includes any and all combinations of the relevant listed items.

[0038] Please refer to Figure 1 The present application provides a maximum pulse width limiting circuit for driving, including: a signal protection module 10, a pulse width control module 20 and an optocoupler driving module 30; wherein the pulse width control module 20 is connected to the signal protection module 10 and the optocoupler driving module 30 respectively, and the signal protection module 10 is used to stabilize the received initial pulse signal; the pulse width control module 20 is used to adjust the pulse width of the initial pulse signal to output a target pulse signal including a target duty cycle; the optocoupler driving module 30 is connected to the pulse width control module 20, and is used to output a driving signal when the target pulse signal is received.

[0039] As an example, the input end of the signal protection module 10 can be connected to the pulse generating circuit for receiving the initial pulse signal. The signal protection module 10 may include a limiting circuit, a current limiting circuit, a filtering circuit, a voltage withstand circuit, etc., which are used to improve the signal quality of the initial pulse signal so that the initial pulse signal meets the input requirements of the pulse width control module 20. The initial pulse signal may be a pulse signal including an initial duty cycle. The present application does not require the initial duty cycle, amplitude, etc. of the initial pulse signal. In addition, the target duty cycle is related to the performance of the circuit to be driven, such as a boost inductor. The present application does not impose specific restrictions on the target duty cycle, and it can be set according to actual needs.

[0040] In the above embodiment, a signal protection module 10, a pulse width control module 20 and an optocoupler drive module 30 are set; wherein the signal protection module 10 is used to stabilize the received initial pulse signal; the pulse width control module 20 is connected to the signal protection module 10, and is used to adjust the pulse width of the initial pulse signal to output a target pulse signal including a target duty cycle; the optocoupler drive module 30 is connected to the pulse width control module 20, and is used to output a drive signal when the target pulse signal is received, thereby controlling the circuit to be driven. The present application stabilizes the initial pulse signal through the signal protection module 10, improves the stability of the initial pulse signal, and thereby ensures the accuracy of the drive signal output by the maximum pulse width limiting circuit for driving, and then adjusts the pulse width of the initial pulse signal through the pulse width control module 20, outputs the target pulse signal including the target duty cycle, isolates the signal through the optocoupler drive module 30, avoids high voltage damage to the maximum pulse width limiting circuit for driving, and outputs a drive signal when the target pulse signal is received, so as to control the circuit to be driven, such as the boost inductor, to work according to the target duty cycle, thereby avoiding saturation of the boost inductor.

[0041] In one embodiment, please refer to Figure 2 The pulse width control module includes: a pulse width adjustment component 210, an impedance adjustment component 220, a switch component 230, a first voltage divider component 240 and a second voltage divider component 250; wherein, the input end of the pulse width adjustment component 210 is connected to the signal protection module, the output end of the pulse width adjustment component 210 is connected to the first end of the impedance adjustment component 220, the second end of the impedance adjustment component 220 is connected to the control end of the switch component 230, the first end of the switch component 230 is respectively connected to the first end of the first voltage divider component 240, the optical coupling driving module, and the first end of the second voltage divider component 250, the second end of the first voltage divider component 240 is connected to the signal protection module, and the second end of the switch component 230 is respectively connected to the second end of the second voltage divider component 250, the common ground end, and the optical coupling driving module.

[0042] Among them, the pulse width adjustment component 210 is used to adjust the pulse width of the initial pulse signal and generate a control signal of the switch component 230. The impedance adjustment component 220 is used to adjust the impedance size to weaken the blocking ability of the high-frequency control signal of the switch component 230, so that the high-frequency control signal of the switch component 230 passes quickly, thereby improving the performance of the pulse control module. The switch component 230 is used to turn on or off when receiving the control signal of the switch component 230, thereby changing the potential of the first end of the first voltage divider component 240, and then outputting a target pulse signal including a target duty cycle.

[0043] In one embodiment, please refer to Figure 3The pulse width modulation component 210 includes: a first diode D1, a first resistor R1, a second resistor R2, a first capacitor C1, a second capacitor C2 and a pulse generating chip U1; wherein, the positive electrode of the first diode D1 is respectively connected to the signal protection module 10, the input terminal TRG of the pulse generating chip U1, and the first end of the first resistor R1, the negative electrode of the first diode D1 is respectively connected to the second end of the first resistor R1, the enable terminal RS of the pulse generating chip U1, and the first power supply (the output voltage of the first power supply can be +15V), the first end of the second resistor R2 is respectively connected to the first power supply and the first end of the first capacitor C1, the second end of the second resistor R2 is respectively connected to the control terminal TH of the pulse generating chip U1 and the first end of the second capacitor C2, and the second end of the first capacitor C1 is respectively connected to the second end of the second capacitor C2 and the common ground terminal GND.

[0044] As an example, the common terminal GND of the pulse generating chip U1 is connected to the common ground terminal GND, the power terminal V+ of the pulse generating chip U1 is connected to the first power supply, the discharge terminal DC of the pulse generating chip U1 is short-circuited with the control terminal TH of the pulse generating chip U1, and the control voltage terminal CTL of the pulse generating chip U1 is connected to the fifth capacitor C5. Among them, the first diode D1 is used to prevent the voltage of the input terminal TRG of the pulse generating chip U1 from being greater than the voltage value output by the first power supply, the first resistor U1 is used to charge the input terminal TRG of the pulse generating chip U1, and the second resistor R2 and the second capacitor C2 are used to form a preset waveform. Since the voltage of the control terminal TH of the pulse generating chip U1 can be adjusted to control the potential of the output terminal OUT and form a control signal of the switch component 230, the preset waveform can be formed by adjusting the resistance and capacitance of the second resistor R2 and the second capacitor C2, so that the potential of the output terminal OUT meets the requirements. In addition, the first capacitor C1 and the fifth capacitor C5 are used for filtering.

[0045] In one embodiment, please continue to refer to Figure 3 The impedance adjustment component 220 includes a third resistor R3 and a third capacitor C3; wherein the first end of the third resistor R3 is respectively connected to the output end OUT of the pulse generating chip U1 and the first end of the third capacitor C3, and the second end of the third resistor R3 is respectively connected to the second end of the third capacitor C3 and the control end of the switch component 230.

[0046] In the above embodiment, by connecting the third resistor R3 and the third capacitor C3 in parallel, the blocking capability of the control signal of the high-frequency switch component 230 can be weakened, so that the control signal of the high-frequency switch component 230 can pass quickly, thereby improving the performance of the pulse control module.

[0047] In one embodiment, please continue to refer to Figure 3The switch component 230 includes a transistor Q1, a gate of the transistor Q1 is connected to the second end of the impedance adjustment component 220, a drain of the transistor Q1 is respectively connected to the first end of the first voltage divider component 240 and the first end of the second voltage divider component 250, and a source of the transistor Q1 is connected to the common ground GND.

[0048] As an example, the switch component 230 also includes a seventh resistor R7, a first end of the seventh resistor R7 is connected to the gate of the transistor Q1, a second end of the seventh resistor R7 is connected to the source of the transistor Q1, and the seventh resistor R7 is used to reduce leakage current to avoid mis-conduction of the transistor Q1.

[0049] In one embodiment, please continue to refer to Figure 3 The first voltage divider component 240 includes a fourth resistor R4, a first end of the fourth resistor R4 is respectively connected to the drain of the transistor Q1, a first end of the fifth resistor R5 is connected to the optocoupler driving module 30, and a second end of the fourth resistor R4 is connected to the signal protection module 10.

[0050] In one embodiment, please continue to refer to Figure 3 The second voltage divider component 250 includes a fifth resistor R5, a first end of the fifth resistor R5 is connected to a first end of the fourth resistor R4, and a second end of the fifth resistor R5 is respectively connected to a source of the transistor Q1, a common ground GND, and the optocoupler driving module 30.

[0051] In one embodiment, the optocoupler driving module includes: a photocoupler U2 and a driving transistor Q2; wherein the primary side of the photocoupler U2 is connected to the pulse width control module, and is used to output a switch control signal when a target pulse signal is received; the control end of the driving transistor Q2 is connected to the secondary side of the photocoupler U2, the first end of the driving transistor Q2 is respectively connected to the first power supply and the secondary side of the photocoupler U2, and the second end of the driving transistor Q2 is connected to the circuit to be driven (not shown), and is used to output a drive signal when a switch control signal is received.

[0052] As an example, the photocoupler U2 may include: a light-emitting diode and a first photosensitive transistor and a second photosensitive transistor; wherein the positive electrode of the light-emitting diode serves as the input terminal A of the photocoupler U2 and is connected to the pulse control module, and the negative electrode of the light-emitting diode serves as the input terminal K of the photocoupler U2 and is connected to the common ground terminal GND; the drain of the first photosensitive transistor serves as the power supply terminal VCC of the photocoupler U2 and is connected to the first power supply, and the source of the first photosensitive transistor serves as the output terminal VO of the photocoupler U2 and is connected to the circuit to be driven; the drain of the second photosensitive transistor serves as the common terminal GND of the photocoupler U2 and is connected to the common ground terminal GND, and the source of the second photosensitive transistor serves as the output terminal VO of the photocoupler U2 and is connected to the circuit to be driven.

[0053] In one embodiment, please continue to refer to Figure 3 The optocoupler driving module also includes: a discharge transistor Q3, a control end of the discharge transistor Q3 is connected to the secondary side of the optocoupler U2, a first end of the discharge transistor Q3 is respectively connected to the first end of the driving transistor Q2 and the circuit to be driven, and a second end of the discharge transistor Q3 is connected to the common ground.

[0054] In the above embodiment, by providing the discharge transistor Q3, the electric energy in the circuit to be driven can be quickly released when the circuit to be driven is turned off, thereby realizing the rapid turning off of the circuit to be driven.

[0055] In one embodiment, please continue to refer to Figure 3 The optocoupler driving module 30 further includes: an eighth resistor R8, a first end of the eighth resistor R8 is connected to the source of the first phototransistor, and a second end of the eighth resistor R8 is respectively connected to the control ends of the driving transistor Q2 and the discharging transistor Q3.

[0056] In one embodiment, please continue to refer to Figure 3 The optocoupler driving module 30 also includes: a ninth resistor R9, a tenth resistor R10, and an eleventh resistor R11; the first end of the ninth resistor R9, the first end of the tenth resistor R10, and the first end of the eleventh resistor R11 are respectively connected to the source of the driving transistor Q2 and the source of the discharging transistor Q3, the second end of the ninth resistor R9, the second end of the tenth resistor R10, and the second end of the eleventh resistor R11 are all connected to the circuit to be driven, and the ninth resistor R9, the tenth resistor R10, and the eleventh resistor R11 are used to limit current.

[0057] In one embodiment, please continue to refer to Figure 3 The optocoupler driving module 30 further includes: a twelfth resistor R12, a first end of the twelfth resistor R12 is respectively connected to the power supply terminal VCC of the optocoupler U2 and the drain of the driving transistor Q2, and a second end of the twelfth resistor R12 is connected to the first power supply.

[0058] In one embodiment, please continue to refer to Figure 3 The optocoupler driving module 30 also includes: a sixth capacitor C6 and a seventh capacitor C7; the positive electrode of the sixth capacitor C6 is respectively connected to the first end of the twelfth resistor R12 and the first end of the seventh capacitor C7, and the second end of the sixth capacitor C6 is respectively connected to the second end of the seventh capacitor C7 and the common ground GND, and the sixth capacitor C6 and the seventh capacitor C7 are used to filter the first power supply.

[0059] In one embodiment, the signal protection module includes: a limiting circuit and a capacitive resistor circuit; wherein the capacitive resistor circuit is respectively connected to the limiting circuit and the pulse width control module; the limiting circuit is used to perform limiting processing on the initial pulse signal when the initial pulse signal is received; the capacitive resistor circuit is used to perform buffer processing on the initial pulse signal when the initial pulse signal is received.

[0060] In one embodiment, please continue to refer to Figure 3 The limiting circuit includes: a second diode D2 and a third diode D3; wherein the anode of the second diode D2 is respectively connected to the cathode of the third diode D3 and the capacitance-resistance circuit, the cathode of the second diode D2 is connected to the second power supply (the output voltage of the second power supply can be +15.5V), and the anode of the third diode D3 is connected to the common ground GND.

[0061] In one embodiment, please continue to refer to Figure 3 The capacitive-resistance circuit includes: a sixth resistor R6 and a fourth capacitor C4; wherein the first end of the sixth resistor R6 is connected to the limiting circuit, the second end of the sixth resistor R6 is connected to the first end of the fourth capacitor C4, and the second end of the fourth capacitor C4 is connected to the pulse width control module.

[0062] In one embodiment, the present application also provides a power factor correction circuit, which includes a maximum pulse width limiting circuit for driving and a circuit to be driven as in any one of the embodiments of the present application; wherein the maximum pulse width limiting circuit for driving is connected to the circuit to be driven.

[0063] In the description of this specification, the description with reference to the terms "some embodiments", "other embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic description of the above terms does not necessarily refer to the same embodiment or example.

[0064] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0065] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A maximum pulse width limiting circuit for driving, characterized in that: include: Signal protection module, used to stabilize the received initial pulse signal; a pulse width control module, connected to the signal protection module, and used to adjust the pulse width of the initial pulse signal to output a target pulse signal including a target duty cycle; The optical coupling driving module is connected to the pulse width control module, and is used for outputting a driving signal when receiving the target pulse signal.

2. The driving maximum pulse width limiting circuit according to claim 1, characterized in that: The pulse width control module includes: a pulse width adjustment component, an impedance adjustment component, a switch component, a first voltage divider component and a second voltage divider component; wherein, the input end of the pulse width adjustment component is connected to the signal protection module, the output end of the pulse width adjustment component is connected to the first end of the impedance adjustment component, the second end of the impedance adjustment component is connected to the control end of the switch component, the first end of the switch component is respectively connected to the first end of the first voltage divider component, the optocoupler drive module, and the first end of the second voltage divider component, the second end of the first voltage divider component is connected to the signal protection module, and the second end of the switch component is respectively connected to the second end of the second voltage divider component, the common ground end, and the optocoupler drive module.

3. The driving maximum pulse width limiting circuit according to claim 2, characterized in that: The pulse width modulation component includes: a first diode, a first resistor, a second resistor, a first capacitor, a second capacitor and a pulse generating chip; wherein the positive electrode of the first diode is respectively connected to the signal protection module, the input end of the pulse generating chip and the first end of the first resistor, the negative electrode of the first diode is respectively connected to the second end of the first resistor, the enable end of the pulse generating chip and the first power supply, the first end of the second resistor is respectively connected to the first power supply and the first end of the first capacitor, the second end of the second resistor is respectively connected to the control end of the pulse generating chip and the first end of the second capacitor, and the second end of the first capacitor is respectively connected to the second end of the second capacitor and the common ground end.

4. The driving maximum pulse width limiting circuit according to claim 3, characterized in that: The impedance adjustment component includes: a third resistor and a third capacitor; wherein the first end of the third resistor is respectively connected to the output end of the pulse generating chip and the first end of the third capacitor, and the second end of the third resistor is respectively connected to the second end of the third capacitor and the control end of the switch component.

5. The driving maximum pulse width limiting circuit according to any one of claims 2 to 4, characterized in that: The switch component comprises a transistor, the gate of the transistor is connected to the second end of the impedance adjustment component, the drain of the transistor is connected to the first end of the first voltage divider component, and the source of the transistor is connected to the common ground terminal; and / or, The first voltage dividing component includes a fourth resistor; and / or, The second voltage dividing component includes a fifth resistor.

6. The driving maximum pulse width limiting circuit according to claim 1, characterized in that: The optical coupler driving module comprises: A photoelectric coupler, the primary side of which is connected to the pulse width control module, and is used to output a switch control signal when receiving the target pulse signal; A driving transistor, wherein the control end of the driving transistor is connected to the secondary side of the photocoupler, the first end of the driving transistor is respectively connected to the first power supply and the secondary side of the photocoupler, and the second end of the driving transistor is connected to the circuit to be driven, for outputting the driving signal when receiving the switch control signal.

7. The driving maximum pulse width limiting circuit according to claim 6, characterized in that: The optical coupler driving module also includes: A discharge transistor, wherein the control end of the discharge transistor is connected to the secondary side of the photocoupler, the first end of the discharge transistor is respectively connected to the first end of the drive transistor and the circuit to be driven, and the second end of the discharge transistor is connected to a common ground end.

8. The driving maximum pulse width limiting circuit according to claim 1, characterized in that: The signal protection module comprises: A limiting circuit, used for performing a limiting process on the initial pulse signal when the initial pulse signal is received; The capacitive-resistance circuit is connected to the amplitude limiting circuit and the pulse width control module respectively, and is used for buffering the initial pulse signal when the initial pulse signal is received.

9. The driving maximum pulse width limiting circuit according to claim 8, characterized in that: The limiting circuit includes: a second diode and a third diode; wherein the anode of the second diode is respectively connected to the cathode of the third diode and the capacitive resistance circuit, the cathode of the second diode is connected to the second power supply, and the anode of the third diode is connected to the common ground.

10. A power factor correction circuit, characterized in that: The power factor correction circuit comprises a maximum pulse width limiting circuit for driving and a circuit to be driven as described in any one of claims 1 to 9; wherein the maximum pulse width limiting circuit for driving is connected to the circuit to be driven.

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