Anti-bounce control circuit and switching power supply

Abstract

The utility model discloses an anti-bounce control circuit and a switching power supply, and relates to the field of switching power supply control, the circuit comprises a switch module, a resistor module, a starter and a voltage regulator, the switch module is respectively connected with the resistor module, the starter and the voltage regulator, the voltage regulator is respectively connected with the starter and the resistor module, and the resistor module is connected with the starter. The resistor module receives a voltage signal of the electrolytic capacitor and sends the voltage signal to the voltage regulator, when the voltage of the voltage signal is larger than a preset first voltage, the voltage regulator is connected with the starter and sends a starting signal to the starter, and when the starter receives the starting signal, the resonance chip is started, and the starting signal is sent to the electrolytic capacitor. And when the switch module receives the voltage signal of the electrolytic capacitor, the connection between the switch module and the resistor module is conducted. Compared with the prior art, by reducing the impedance of the resistor between the voltage regulator and the electrolytic capacitor, circuit output abnormity and damage to components in the circuit caused by the bounce phenomenon of the circuit are avoided.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of switching power supply control, and particularly relates to a reverse jump prevention control circuit and a switching power supply. BACKGROUND

[0002] At present, in the use of switching power supply with PFC (Power Factor Correction) requirement, in order to ensure the normal work of LLC (resonant circuit) behind, a detection voltage circuit is generally set on a large electrolytic capacitor, and the LLC chip will work normally only when the voltage is greater than the required value (about 390V is generally set), so as to prevent the damage of elements caused by too low voltage.

[0003] If the output voltage of the large electrolytic capacitor still has ripple, when the detected voltage is just lower than 390V during normal work, the LLC will be closed to work, resulting in abnormal output of the circuit. CONTENT OF THE INVENTION

[0004] The main purpose of the present application is to provide a reverse jump prevention control circuit and a switching power supply, which aims to solve the technical problem of output abnormality and reverse jump phenomenon caused by the ripple of the output voltage of the large electrolytic capacitor in the prior art.

[0005] To achieve the above purpose, the present application provides an output fast-off circuit, which is applied to a switching power supply, and the reverse jump prevention control circuit comprises a switching module, a resistance module, a starter and a voltage regulator.

[0006] The switching module is connected with the resistance module, the starter and the voltage regulator respectively, and the voltage regulator is connected with the starter and the resistance module respectively.

[0007] The resistance module is used for receiving the voltage signal of the electrolytic capacitor and sending it to the voltage regulator.

[0008] The voltage regulator is used for conducting the connection between the voltage regulator and the starter and sending the starting signal to the starter when the voltage of the voltage signal is greater than the preset first voltage.

[0009] The starter is used for starting the resonant chip when the starting signal is received.

[0010] The switching module is used for conducting the connection between the switching module and the resistance module when the voltage signal of the electrolytic capacitor is received, so as to reduce the impedance between the electrolytic capacitor and the voltage regulator, thereby avoiding the reverse jump phenomenon of the circuit.

[0011] Optionally, the voltage regulator is further configured to keep the circuit between the voltage regulator and the starter conducting and send a start signal to the starter to reduce the influence of the electrolytic capacitor voltage ripple when the impedance between the electrolytic capacitor and the voltage regulator is reduced and the voltage of the voltage signal is greater than a preset second voltage.

[0012] Optionally, the voltage regulator is further configured to disconnect the connection between the voltage regulator and the starter and send a close signal to the starter when the voltage of the voltage signal is less than a preset first voltage.

[0013] The starter is further configured to stop starting the resonant chip when the close signal is received.

[0014] Optionally, the switch module comprises a triode, a first resistor, a second resistor and a third resistor.

[0015] The base of the triode is connected to the second end of the first resistor and the starter, the emitter of the triode is connected to the second end of the second resistor, the collector of the triode is connected to the first end of the third resistor, the second end of the third resistor is connected to the resistance module and the voltage regulator, the first end of the first resistor is connected to the electrolytic capacitor, the first end of the second resistor and the resistance module, and the first end of the second resistor is connected to the electrolytic capacitor and the resistance module.

[0016] Optionally, the resistance module comprises a fourth resistor.

[0017] The first end of the fourth resistor is connected to the electrolytic capacitor and the switch module, and the second end of the fourth resistor is connected to the switch module and the voltage regulator.

[0018] Optionally, the starter comprises an optoelectronic coupler.

[0019] The first end of the optoelectronic coupler is connected to the switch module, and the second end of the optoelectronic coupler is connected to the voltage regulator.

[0020] Optionally, the voltage regulator comprises a voltage reference chip.

[0021] The first end of the voltage reference chip is connected to the resistance module and the switch module, the second end of the voltage reference chip is connected to the starter, and the third end of the voltage reference chip is grounded.

[0022] Optionally, the anti-bounce control circuit further comprises a fifth resistor and a capacitor.

[0023] The first end of the fifth resistor is connected with the first end of the capacitor, the resistance module, the switch module and the voltage regulator respectively, the first end of the capacitor is connected with the first end of the capacitor, the resistance module, the switch module and the voltage regulator respectively, and the voltage regulator is connected with the second end of the fifth resistor and the second end of the capacitor respectively.

[0024] In addition, the utility model discloses a switching power supply, the switching power supply includes the control circuit of preventing bounce as described above.

[0025] The one or more technical solutions provided by the present application have at least the following effects:

[0026] The present application provides a kind of control circuit of preventing bounce, the circuit is applied to switching power supply, the control circuit of preventing bounce includes: switch module, resistance module, starter and voltage regulator, the switch module is connected with the resistance module, the starter and the voltage regulator respectively, the voltage regulator is connected with the starter and the resistance module respectively, the resistance module is used to receive the voltage signal of electrolytic capacitor and send it to the voltage regulator, the voltage regulator is used to when the voltage of voltage signal is greater than preset first voltage, the connection between the starter is turned on and sends start signal to the starter, the starter is used to when receiving start signal, start resonant chip, the switch module is used to when receiving the voltage signal of electrolytic capacitor, the connection between the resistance module is turned on, to make the impedance between the electrolytic capacitor and the voltage regulator reduce, to avoid the bounce phenomenon of circuit.Compared with prior art, the present application reduces the impedance of resistance between voltage regulator and electrolytic capacitor, expands the voltage range of voltage regulator switch, reduces the influence of electrolytic capacitor voltage ripple (electrolytic capacitor voltage ripple can cause the bounce phenomenon of voltage regulator), to avoid the bounce phenomenon of voltage regulator in circuit to cause circuit output exception and damage of component in circuit. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present application or prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced as follows, and obviously, other drawings can also be obtained by those skilled in the art without creative labor.

[0028] Figure 1 The structural schematic diagram of the first embodiment of the control circuit of preventing bounce provided by the embodiments of the present application is shown in the figure.

[0029] Figure 2 The structural schematic diagram of the second embodiment of the control circuit of preventing bounce provided by the embodiments of the present application is shown in the figure.

[0030] Figure 3 Voltage detection circuit diagram of traditional switching power supply;

[0031] Figure 4 Circuit principle diagram of the second embodiment of the anti-bounce control circuit proposed in the embodiments of the present application.

[0032] Explanation of reference numerals:

[0033]

[0034] The purposes, functional features and advantages of the present application will be further described with reference to the embodiments and the accompanying drawings. DETAILED DESCRIPTION

[0035] It should be understood that the specific embodiments described herein are merely intended to explain the technical solutions of the present application, and are not intended to limit the present application.

[0036] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative work fall within the scope of protection of the present application.

[0037] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present application are only used to explain the relative positional relationship, movement condition, etc. between components in a certain posture (as shown in the drawings), and if the certain posture changes, the directional indications also change accordingly.

[0038] In addition, the descriptions involving “first”, “second” and the like in the present application are only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features limited by “first”, “second” can explicitly or implicitly include at least one of the features. In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the realization of those of ordinary skill in the art, and when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, and is not within the scope of protection claimed by the present application.

[0039] The main solution of the embodiments of the present application is: by reducing the impedance of the resistance between the voltage regulator 4 and the electrolytic capacitor, expanding the voltage range of the voltage regulator 4 switch, reducing the influence of the electrolytic capacitor voltage ripple, thereby avoiding the abnormal output of the circuit caused by the bounce phenomenon of the voltage regulator 4 in the circuit and the damage of the components in the circuit.

[0040] Currently, in switching power supplies requiring PFC (Power Factor Correction), a voltage detection circuit is typically installed on the large electrolytic capacitor to ensure the normal operation of the subsequent LLC (resonant circuit). The LLC chip will only operate normally when the voltage across the electrolytic capacitor exceeds the required value (usually set around 390V), preventing damage to components due to low voltage. However, because the output voltage of the large electrolytic capacitor still has ripple, if the voltage detected by voltage regulator 4 during normal operation is slightly below 390V, the LLC will shut down, leading to abnormal circuit output.

[0041] This application provides a solution: an anti-backlash control circuit applied to a switching power supply. The anti-backlash control circuit includes a switching module 1, a resistor module 2, a starter 3, and a voltage regulator 4. The switching module 1 is connected to the resistor module 2, the starter 3, and the voltage regulator 4. The voltage regulator 4 is connected to the starter 3 and the resistor module 2. The resistor module 2 receives the voltage signal from the electrolytic capacitor and sends it to the voltage regulator 4. When the voltage signal exceeds a preset first voltage, the voltage regulator 4 connects to the starter 3 and sends a start signal to the starter 3. Upon receiving the start signal, the starter 3 activates a resonant chip. The switching module 1 connects to the resistor module 2 upon receiving the voltage signal from the electrolytic capacitor, thereby reducing the impedance between the electrolytic capacitor and the voltage regulator 4 to prevent circuit backlash. Compared with the prior art, this application expands the voltage range of the voltage regulator 4 by reducing the impedance between the voltage regulator 4 and the electrolytic capacitor, and reduces the influence of the electrolytic capacitor voltage ripple (which causes the voltage regulator 4 to bounce back), thereby avoiding abnormal circuit output and damage to components caused by the bounce back phenomenon of the voltage regulator 4 in the circuit.

[0042] Based on this, the embodiments of this application provide an anti-rebound control circuit.

[0043] refer to Figure 1 , Figure 1 This is a schematic diagram of the structure of the first embodiment of the anti-rebound control circuit proposed in this application.

[0044] Considering that the voltage ripple of the electrolytic capacitor can cause the voltage regulator 4 to bounce back, leading to abnormal circuit output and damage to components, and in order to avoid the bounce back phenomenon of the voltage regulator 4, such as... Figure 1 As shown, the anti-rebound control circuit in this embodiment includes: a switch module 1, a resistor module 2, a starter 3, and a voltage regulator 4;

[0045] The switch module 1 is connected with the resistance module 2, the starter 3 and the voltage regulator 4 respectively, and the voltage regulator 4 is connected with the starter 3 and the resistance module 2 respectively;

[0046] The resistance module 2 is used for receiving the voltage signal of the electrolytic capacitor and sending it to the voltage regulator 4;

[0047] The voltage regulator 4 is used for turning on the connection between the voltage regulator 4 and the starter 3 and sending the starting signal to the starter 3 when the voltage of the voltage signal is greater than the preset first voltage;

[0048] The starter 3 is used for starting the resonant chip when the starting signal is received;

[0049] The switch module 1 is used for turning on the connection between the switch module 1 and the resistance module 2 when the voltage signal of the electrolytic capacitor is received, so as to reduce the impedance between the electrolytic capacitor and the voltage regulator 4, thereby avoiding the bounce phenomenon of the circuit.

[0050] It should be noted that the anti-bounce control circuit is applied to the voltage detection circuit of the switching power supply, the voltage of the voltage signal is a direct current voltage, and the preset first voltage can be 389V or can be set according to actual conditions, that is, when the voltage of the electrolytic capacitor is greater than 389V, the voltage regulator 4 and the starter 3 are in an open state (conducting state), thereby starting the resonant chip; when the voltage of the electrolytic capacitor is less than 389V, the voltage regulator 4 and the starter 3 are in a closed state, thereby closing the resonant chip.

[0051] It can be understood that the resonant chip is one of the core components in the switching power supply, and the resonant principle is used to realize the conversion and control of electric energy. The resonant chip has the advantages of high efficiency, low loss and wide input voltage range. The resonant chip realizes the stability and adjustment of the output voltage by precisely controlling the switching frequency and duty cycle.

[0052] It should be noted that the bounce phenomenon of the switching power supply usually shows that the output voltage fluctuates or oscillates instantaneously in a short time, specifically, the voltage rises and falls rapidly. The bounce phenomenon affects the normal work of the circuit, reduces the stability and reliability of the circuit.

[0053] In a specific implementation, the resistor module 2 is configured to receive a voltage signal of the electrolytic capacitor and send the voltage signal to the voltage regulator 4, the voltage regulator 4 is configured to turn on a connection between the voltage regulator 4 and the starter 3 and send a start signal to the starter 3 when a voltage of the voltage signal is greater than a preset first voltage, the starter 3 is configured to start the resonant chip when the start signal is received, and the switch module 1 is configured to turn on a connection between the switch module 1 and the resistor module 2 when the voltage signal of the electrolytic capacitor is received, so that impedance between the electrolytic capacitor and the voltage regulator 4 is reduced, the influence of the electrolytic capacitor voltage ripple is reduced (the electrolytic capacitor voltage ripple can cause the voltage regulator 4 to bounce), and the bounce of the voltage regulator 4 in the circuit is avoided to cause abnormal output of the circuit and damage to components in the circuit.

[0054] Further, the voltage regulator 4 is further configured to keep the circuit between the voltage regulator 4 and the starter 3 turned on and send a start signal to the starter 3 when the impedance between the electrolytic capacitor and the voltage regulator 4 is reduced and a voltage of the voltage signal of the electrolytic capacitor is greater than a preset second voltage, so as to reduce the influence of the electrolytic capacitor voltage ripple.

[0055] It should be noted that the preset second voltage can be 303V, or can be set according to actual conditions, that is, when the voltage of the electrolytic capacitor is less than 303V, the voltage regulator 4 and the starter 3 are in a closed state, so that the resonant chip is closed; when the voltage of the electrolytic capacitor is greater than 303V, the voltage regulator 4 and the starter 3 are in an open state, so that the resonant chip is started. The output voltage of the large electrolytic capacitor can be avoided to have ripple, and if the voltage is just lower than 389V when working normally, the resonant chip will be closed, which causes the voltage regulator 4 to output abnormally, and also prevents the circuit components from being damaged due to low voltage.

[0056] In a specific implementation, the voltage regulator 4 keeps the circuit between the voltage regulator 4 and the starter 3 turned on and sends a start signal to the starter 3 when the impedance between the electrolytic capacitor and the voltage regulator 4 is reduced and a voltage of the voltage signal of the electrolytic capacitor is greater than a preset second voltage, so as to reduce the influence of the electrolytic capacitor voltage ripple.

[0057] Further, the voltage regulator 4 is further configured to turn off a connection between the voltage regulator 4 and the starter 3 and send a close signal to the starter 3 when a voltage of the voltage signal is less than a preset first voltage.

[0058] The starter 3 is further configured to stop starting the resonant chip when the close signal is received.

[0059] It should be noted that the close signal can be a voltage signal or a current signal, and can be set according to actual conditions, and the embodiment is not limited.

[0060] In a specific implementation, the voltage regulator 4 disconnects the connection with the starter 3 and sends a shutdown signal to the starter 3 when the voltage of the voltage signal is less than the preset first voltage, and the starter 3 stops starting the resonant chip when receiving the shutdown signal, thereby reducing the influence of the voltage ripple of the electrolytic capacitor.

[0061] Based on the first embodiment of the present application, the same or similar contents as the above first embodiment can be referred to the above introduction, and will not be described in detail. On this basis, please refer to Figure 2 , Figure 2 The structure diagram of the second embodiment of the anti-bounce control circuit proposed in the embodiment of the present application.

[0062] It is considered that by reducing the impedance between the voltage regulator 4 and the electrolytic capacitor, the voltage range of the switch of the voltage regulator 4 can be expanded, the influence of the voltage ripple of the electrolytic capacitor is reduced, and the bounce phenomenon of the voltage regulator 4 in the circuit is avoided, as Figure 2 shown, the switch module 1 includes a triode 11, a first resistor 12, a second resistor 13 and a third resistor 14;

[0063] The base of the triode 11 is connected with the second end of the first resistor 12 and the starter 3, respectively, the emitter of the triode 11 is connected with the second end of the second resistor 13, the collector of the triode 11 is connected with the first end of the third resistor 14, the second end of the third resistor 14 is connected with the resistor module 2 and the voltage regulator 4, respectively, the first end of the first resistor 12 is connected with the electrolytic capacitor, the first end of the second resistor 13 and the resistor module 2, respectively, and the first end of the second resistor 13 is connected with the electrolytic capacitor and the resistor module 2.

[0064] It should be noted that the first resistor 12, the second resistor 13 and the third resistor 14 can be composed of a plurality of small resistance resistors, the first resistor 12, the second resistor 13 and the third resistor 14 can be a surface mount resistor, also can be a plug-in color ring resistor, also can be set according to the actual situation, the triode 11 can be a PNP triode 11, also can be set according to the actual situation, the triode 11 is turned on when the voltage of the electrolytic capacitor is greater than the preset second voltage (i.e. the second resistor 13 and the third resistor 14 are connected in series), that is, the voltage between the base and the emitter of the triode 11 is less than the turn-on voltage (usually -0.6V to -0.7V).

[0065] In a specific implementation, the triode 11 turns on the connection between the second resistor 13 and the third resistor 14 when the voltage of the electrolytic capacitor is greater than the preset second voltage, and the second resistor 13 and the third resistor 14 are connected in series and are connected in parallel with the resistor module 2, thereby reducing the impedance of the resistor between the voltage regulator 4 and the electrolytic capacitor, expanding the voltage range of the switch of the voltage regulator 4, reducing the influence of the voltage ripple of the electrolytic capacitor (the voltage ripple of the electrolytic capacitor can cause the voltage regulator 4 to bounce), thereby avoiding the abnormal output of the circuit and the damage of the components in the circuit caused by the bounce of the voltage regulator 4 in the circuit.

[0066] Further, the resistor module 2 comprises: a fourth resistor 21;

[0067] The first end of the fourth resistor 21 is connected with the electrolytic capacitor and the switch module 1 respectively, and the second end of the fourth resistor 21 is connected with the switch module 1 and the voltage regulator 4 respectively.

[0068] It should be noted that the fourth resistor 21 can be a surface mount resistor, a plug-in color ring resistor, or can be set according to actual conditions.

[0069] Further, the starter 3 comprises: an optoelectronic coupler 31;

[0070] The first end of the optoelectronic coupler 31 is connected with the switch module 1, and the second end of the optoelectronic coupler 31 is connected with the voltage regulator 4.

[0071] It should be noted that the optoelectronic coupler 31 is composed of a light-emitting source and a light receiver, and is usually assembled in the same sealed shell and is isolated from each other by a transparent insulator. The working principle of the optoelectronic coupler 31 is based on the conversion process of electricity-optics-electricity. When the input electrical signal drives the light-emitting diode, it will emit light of a certain wavelength, which is received by the light receiver and converted into photoelectric current, and then output after further amplification, thus completing the conversion process from electrical signal to optical signal and then to electrical signal, and realizing the electrical isolation between the input and output circuits.

[0072] In a specific implementation, when the voltage regulator 4 is in an open state, the light-emitting diode in the optoelectronic coupler 31 emits light of a certain wavelength, which is received by the light receiver and converted into photoelectric current to drive the resonant chip.

[0073] Further, the voltage regulator 4 comprises: a voltage reference chip 41;

[0074] The first end of the voltage reference chip 41 is connected with the resistor module 2 and the switch module 1 respectively, the second end of the voltage reference chip 41 is connected with the starter 3 respectively, and the third end of the voltage reference chip 41 is grounded.

[0075] It should be noted that the voltage regulator 4 is a control device for detecting the electrolytic capacitor voltage, and the voltage reference chip 41 can be AZ431, or can be set by itself according to actual conditions, and the embodiment is not limited.

[0076] In a specific implementation, when the voltage regulator 4 detects that the voltage of the electrolytic capacitor is greater than the preset second voltage, the voltage regulator 4 and the starter 3 are in an open state, so as to start the resonant chip through the starter 3, and when the voltage regulator 4 detects that the voltage of the electrolytic capacitor is less than the preset second voltage, the voltage regulator 4 and the starter 3 are in a closed state, so as to close the resonant chip through the starter 3.

[0077] Further, the anti-bounce control circuit further comprises a fifth resistor 51 and a capacitor 52.

[0078] The first end of the fifth resistor 51 is connected with the first end of the capacitor 52, the resistance module 2, the switch module 1 and the voltage regulator 4 respectively, the first end of the capacitor 52 is connected with the first end of the capacitor 52, the resistance module 2, the switch module 1 and the voltage regulator 4 respectively, and the voltage regulator 4 is connected with the second end of the fifth resistor 51 and the second end of the capacitor 52 respectively.

[0079] It should be noted that the resistance value of the fifth resistor 51 can affect the voltage range of the voltage regulator 4 switch, and the resistance value of the fifth resistor 51 can be set by itself according to actual conditions, and the embodiment is not limited.

[0080] It should be noted that, as shown in Figure 3 If R1=120kΩ, R1'=680kΩ, R1''=680kΩ, R4=150kΩ, R4'=120kΩ, R4''=150kΩ, and R5=2.7kΩ, the conduction voltage of the voltage regulator 4 is: (1+R4+R4'+R4'') / R5*2.5=389V, as shown in Figure 4 If R2=1MΩ, R2'=240kΩ, and R3=240kΩ, the abnormal voltage of the voltage regulator 4 is: [1+(R4+R4'+R4'') / / (R2+ R2'+R3)] / R5*2.5=303V.

[0081] It can be understood that when the output voltage of the electrolytic capacitor is greater than 389V, the voltage regulator 4 and the starter 3 are in the open state (conduction state), thereby starting the resonance chip. When the output voltage of the electrolytic capacitor is less than 303V, the voltage regulator 4 and the starter 3 are in the closed state, thereby closing the resonance chip; when the voltage of the electrolytic capacitor is greater than 303V, the voltage regulator 4 and the starter 3 are in the open state, thereby starting the resonance chip. The ripple of the output voltage of the large electrolytic capacitor can be avoided, and if the voltage is just a little lower than 389V when normally working, the resonance chip will be closed to work, thereby causing the voltage regulator 4 to output abnormally, and preventing the circuit components from being damaged due to the excessively low voltage.

[0082] To achieve the above object, the application further provides a switching power supply comprising the anti-rebound control circuit.

[0083] The preferred embodiments of the application are described above, but the patent scope of the application is not limited by the above, and any equivalent structure or equivalent process transformation using the content of the specification and drawings, or direct or indirect application in other related technical fields, are also included in the patent protection scope of the application.

Claims

1. A control circuit for preventing bounce, characterized in that The circuit is applied to a switching power supply, and the anti-bounce control circuit comprises a switching module, a resistance module, a starter and a voltage regulator; The switching module is connected with the resistance module, the starter and the voltage regulator respectively, and the voltage regulator is connected with the starter and the resistance module respectively; The resistance module is configured to receive a voltage signal of an electrolytic capacitor and send the voltage signal to the voltage regulator; The voltage regulator is configured to, when the voltage of the voltage signal is greater than a preset first voltage, turn on a connection between the voltage regulator and the starter and send a starting signal to the starter; The starter is configured to, when the starting signal is received, start a resonant chip; The switching module is configured to, when the voltage signal of the electrolytic capacitor is received, turn on a connection between the switching module and the resistance module, so that impedance between the electrolytic capacitor and the voltage regulator is reduced to avoid a bounce phenomenon of the circuit.

2. The anti-bounce control circuit of claim 1, wherein, The voltage regulator is further configured to, when the impedance between the electrolytic capacitor and the voltage regulator is reduced and the voltage of the voltage signal of the electrolytic capacitor is greater than a preset second voltage, keep the connection between the voltage regulator and the starter turned on and send the starting signal to the starter to reduce an influence of voltage ripple of the electrolytic capacitor.

3. The anti-bounce control circuit of claim 2, wherein, The voltage regulator is further configured to, when the voltage of the voltage signal is less than the preset first voltage, turn off the connection between the voltage regulator and the starter and send a closing signal to the starter; The starter is further configured to, when the closing signal is received, stop starting the resonant chip.

4. The anti-bounce control circuit of claim 1, wherein, The switching module comprises a triode, a first resistor, a second resistor and a third resistor; The base of the triode is connected with the second end of the first resistor and the starter respectively, the emitter of the triode is connected with the second end of the second resistor, the collector of the triode is connected with the first end of the third resistor, the second end of the third resistor is connected with the resistance module and the voltage regulator respectively, the first end of the first resistor is connected with the electrolytic capacitor, the first end of the second resistor and the resistance module respectively, and the first end of the second resistor is connected with the electrolytic capacitor and the resistance module respectively.

5. The anti-bounce control circuit of claim 1, wherein, The resistance module comprises a fourth resistor; The first end of the fourth resistor is connected with the electrolytic capacitor and the switching module respectively, and the second end of the fourth resistor is connected with the switching module and the voltage regulator respectively.

6. The anti-bounce control circuit of claim 1, wherein, The starter comprises an optoelectronic coupler; The first end of the optoelectronic coupler is connected with the switching module, and the second end of the optoelectronic coupler is connected with the voltage regulator.

7. The anti-bounce control circuit of claim 1, wherein, The voltage regulator comprises a voltage reference chip; The first end of the voltage reference chip is connected with the resistance module and the switching module respectively, the second end of the voltage reference chip is connected with the starter respectively, and the third end of the voltage reference chip is grounded.

8. The anti-bounce control circuit of claim 1, wherein, The anti-bounce control circuit further comprises a fifth resistor and a capacitor; The first end of the fifth resistor is connected with the first end of the capacitor, the resistor module, the switch module and the voltage regulator respectively, the first end of the capacitor is connected with the first end of the capacitor, the resistor module, the switch module and the voltage regulator respectively, and the voltage regulator is connected with the second end of the fifth resistor and the second end of the capacitor respectively.

9. A switching power supply, characterized by The switching power supply comprises the anti-rebound control circuit according to any one of claims 1 to 8.

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