Control circuit of impulse current suppression circuit and switching power supply

Abstract

The utility model relates to a control circuit of an impact current suppression circuit and a switching power supply. The control circuit comprises a voltage stabilization isolation driving module, a suppression module, a quick start module and a threshold voltage detection module. The voltage stabilization isolation driving module generates stable voltage for the suppression module to work according to bus voltage of an input bus; the suppression module suppresses impact current of the switching power supply; the quick start module provides working voltage for the threshold voltage detection module based on the bus voltage; the threshold voltage detection module outputs a conduction signal to the voltage stabilization isolation driving module and outputs a closing signal to the quick start module based on the power supply voltage. The threshold voltage detection module is used for detecting the power supply voltage and accurately controlling the suppression module to be switched on or switched off based on the power supply voltage, so that the circuit can be effectively suppressed from being impacted when the switching power supply is quickly and repeatedly switched on and switched off, and a current-limiting resistor can be prevented from being burnt down; and meanwhile, the requirements of no auxiliary source, low cost and high inhibition can be met.

Description

Technical Field

[0001] The utility model relates to the technical field of switching power supplies, and more specifically to a control circuit of an impact current suppression circuit and a switching power supply. Background Art

[0002] When the switching power supply is started, a large inrush current will be generated due to the charging of the bus electrolytic capacitor by the input bus, especially when the high voltage input is used. If it is not suppressed, the peak current of a single machine will be as high as 60-70A or even higher, and the current will be superimposed when multiple devices are running in parallel. For large-area centralized wiring applications (such as greenhouse plant lighting products), such a large inrush current can easily trigger the overcurrent protection of the circuit breaker, resulting in a startup trip. Therefore, most customers currently have requirements for the inrush current of the power supply, so the switching power supply product needs to add the function of inrush current suppression when designing.

[0003] The current surge current suppression circuit is mainly: electronic switch (such as Mosfet) + current limiting resistor: suitable for small and medium power applications without auxiliary source. However, this suppression circuit cannot control the switch closure and judgment in time, especially when the machine is turned on and off quickly and repeatedly, it cannot effectively suppress the machine. In addition, the control circuit is complex, prone to malfunction and even lock problems. In severe cases, the current limiting resistor will burn out and the power supply cannot be restarted. Utility Model Content

[0004] The technical problem to be solved by the utility model is to provide a control circuit of an impulse current suppression circuit and a switching power supply.

[0005] The technical solution adopted by the utility model to solve the technical problem is: constructing a control circuit of an impact current suppression circuit, including: a voltage stabilizing isolation driving module, a suppression module, a fast starting module and a threshold voltage detection module;

[0006] The input end of the voltage stabilizing isolation driving module is connected to the input bus of the switching power supply, the output end of the voltage stabilizing isolation driving module is connected to the suppression module, the first end of the fast start module is connected to the input bus, the second end of the fast start module is connected to the first end of the threshold voltage detection module, and the second end of the threshold voltage detection module is connected to the power supply circuit of the power circuit of the switching power supply;

[0007] The voltage-stabilizing isolation driving module generates a stable voltage for the suppression module to work according to the bus voltage of the input bus;

[0008] The suppression module is used to suppress the inrush current of the switching power supply;

[0009] The fast start module provides an operating voltage to the threshold voltage detection module based on the bus voltage;

[0010] The threshold voltage detection module is used to detect the supply voltage of the power supply circuit and output a conduction signal to the voltage stabilizing isolation driving module and a shutdown signal to the fast start module based on the supply voltage.

[0011] In the control circuit of the impact current suppression circuit described in the utility model, the voltage stabilizing isolation driving module includes: a peak holding circuit, a first voltage stabilizing circuit and an isolation driving circuit;

[0012] The input end of the peak holding circuit is connected to the input bus, the output end of the peak holding circuit is grounded, the input end of the first voltage stabilizing circuit is connected to the peak holding circuit, the output end of the first voltage stabilizing circuit is connected to the input end of the isolation driving circuit, and the output end of the isolation driving circuit is connected to the suppression module;

[0013] The peak holding circuit is used to hold the peak value of the bus voltage;

[0014] The first voltage stabilizing circuit is used to generate a stable voltage for the suppression module to work according to the bus voltage;

[0015] The isolation driving circuit is used to perform an isolation operation and output a driving signal to the suppression module.

[0016] In the control circuit of the impulse current suppression circuit described in the utility model, the peak holding circuit includes: a third diode and a fifth capacitor; the first voltage stabilizing circuit includes: a first resistor and a first voltage stabilizing tube; the isolation driving circuit includes: a first capacitor, a switch part of a photocoupler, a second resistor, a second capacitor and a third resistor;

[0017] The anode of the third diode is connected to the input bus, the cathode of the third diode is connected to the first end of the fifth capacitor and the first end of the first resistor, the second end of the fifth capacitor is grounded, the second end of the first resistor is connected to the cathode of the first voltage regulator tube, the input end of the switch part of the photocoupler and the first end of the first capacitor, and the anode of the first voltage regulator tube is grounded;

[0018] The second end of the first capacitor is grounded, the output end of the switch part of the optocoupler is connected to the first end of the second resistor, the second end of the second resistor is connected to the first end of the second capacitor, the first end of the third resistor and the suppression module, and the second end of the second capacitor and the second end of the third resistor are grounded.

[0019] In the control circuit of the impulse current suppression circuit described in the utility model, the suppression module includes: a switch circuit and a current limiting circuit;

[0020] The first end of the switch circuit is connected to the voltage stabilizing isolation driving circuit, and the second end of the switch circuit is connected to the current limiting circuit;

[0021] The switch circuit is used to control the on or off of the current limiting circuit; the current limiting circuit is used to suppress the impact current when it is on.

[0022] In the control circuit of the impulse current suppression circuit described in the utility model, the switch circuit includes: a first switch tube; the current limiting circuit includes: a current limiting resistor;

[0023] The first end of the first switch tube is connected to the output end of the voltage stabilizing isolation drive circuit, the second end of the first switch tube is connected to the input end of the current limiting resistor, and the third end of the first switch tube is connected to the output end of the current limiting resistor.

[0024] In the control circuit of the inrush current suppression circuit described in the utility model, the quick start module includes: a quick charging circuit and a second voltage stabilizing circuit;

[0025] The input end of the fast charging circuit is connected to the input bus, the output end of the fast charging circuit is connected to the threshold voltage detection module, and the second voltage stabilizing circuit is connected to the fast charging circuit;

[0026] The fast charging circuit is used to provide an operating voltage to the threshold voltage detection module based on the bus voltage;

[0027] The second voltage stabilizing circuit is used to cooperate with the fast charging circuit to set a charging cut-off voltage.

[0028] In the control circuit of the inrush current suppression circuit described in the utility model, the fast charging circuit includes: a sixth resistor, a second switch tube, a first diode and a third capacitor; the second voltage stabilizing circuit includes: a fifth resistor, a second voltage stabilizing tube and a fourth capacitor;

[0029] The first end of the sixth resistor and the first end of the fifth resistor are connected to the input bus, the second end of the sixth resistor is connected to the first end of the second switch tube, the second end of the second switch tube is connected to the anode of the first diode, the third end of the second switch tube is connected to the second end of the fifth resistor, the cathode of the second voltage regulator tube and the first end of the fourth capacitor, the anode of the second voltage regulator tube is grounded, the second end of the fourth capacitor is grounded, the cathode of the first diode is connected to the first end of the third capacitor and the threshold voltage detection module, and the second end of the third capacitor is grounded.

[0030] In the control circuit of the impulse current suppression circuit described in the utility model, the threshold voltage detection module includes: a threshold monitoring circuit and an isolation circuit;

[0031] The threshold monitoring circuit is connected to the quick start module and the power supply circuit respectively, and the isolation circuit is connected to the threshold monitoring circuit;

[0032] The threshold monitoring circuit is used to detect the supply voltage of the power supply circuit and drive the isolation circuit to output the conduction signal to the voltage stabilizing isolation drive module based on the supply voltage, and output a shutdown signal to the fast start module.

[0033] In the control circuit of the impulse current suppression circuit described in the utility model, the threshold monitoring circuit includes: a reference device, a second diode, a ninth resistor and a tenth resistor; the isolation circuit includes: a seventh resistor, an eighth resistor and a power-on part of a photoelectric coupler;

[0034] The first end of the reference device is connected to the second end of the power supply part of the photocoupler, the second end of the reference device is connected to the second end of the ninth resistor and the first end of the tenth resistor, the third end of the reference device is grounded, the second end of the tenth resistor is grounded, the first end of the ninth resistor is connected to the power supply circuit and the anode of the second diode, and the cathode of the second diode is connected to the cathode of the first diode;

[0035] A first end of the seventh resistor is connected to the quick start module, a second end of the seventh resistor is connected to a first end of the power supply portion of the photocoupler and a first end of the eighth resistor, and a second end of the eighth resistor is grounded.

[0036] The utility model also provides a switching power supply, comprising: a control circuit of the above-mentioned impulse current suppression circuit.

[0037] The control circuit and switching power supply of the inrush current suppression circuit of the utility model have the following beneficial effects: including: a voltage-stabilizing isolation drive module, a suppression module, a quick start module and a threshold voltage detection module; the voltage-stabilizing isolation drive module generates a stable voltage for the suppression module to work according to the bus voltage of the input bus; the suppression module suppresses the inrush current of the switching power supply; the quick start module provides the threshold voltage detection module with an operating voltage based on the bus voltage; the threshold voltage detection module outputs a conduction signal to the voltage-stabilizing isolation drive module and a shutdown signal to the quick start module based on the power supply voltage. The utility model detects the power supply voltage through the threshold voltage detection module and accurately controls the suppression module to turn on or off based on the power supply voltage, thereby effectively suppressing the inrush circuit when the switching power supply is turned on and off quickly and repeatedly, and can also avoid the current limiting resistor from being burned, while also meeting the requirements of no auxiliary source, low cost and high suppression. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0039] Figure 1 It is a principle block diagram of the control circuit of the impulse current suppression circuit provided by the utility model;

[0040] Figure 2 It is a circuit diagram of a preferred embodiment of a control circuit of an impulse current suppression circuit provided by the utility model. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0042] Figure 1 The present invention provides a principle block diagram of a control circuit of an inrush current suppression circuit according to an embodiment of the present invention. The control circuit of the inrush current suppression circuit can be applied to small and medium power circuits without auxiliary sources that require inrush current.

[0043] Specifically, Figure 1 As shown, the control circuit of the inrush current suppression circuit includes: a voltage stabilizing isolation driving module 11 , a suppression module 12 , a fast starting module 13 and a threshold voltage detection module 14 .

[0044] The input end of the voltage stabilizing isolation driving module 11 is connected to the input bus of the switching power supply, the output end of the voltage stabilizing isolation driving module 11 is connected to the suppression module 12, the first end of the quick start module 13 is connected to the input bus, the second end of the quick start module 13 is connected to the first end of the threshold voltage detection module 14, and the second end of the threshold voltage detection module 14 is connected to the power supply circuit of the power circuit of the switching power supply.

[0045] Among them, the voltage-stabilizing isolation drive module 11 generates a stable voltage for the suppression module 12 to work according to the bus voltage of the input bus; the suppression module 12 is used to suppress the impact current of the switching power supply; the quick start module 13 provides a working voltage to the threshold voltage detection module 14 based on the bus voltage; the threshold voltage detection module 14 is used to detect the power supply voltage of the power supply circuit and output a conduction signal to the voltage-stabilizing isolation drive module 11 and a shutdown signal to the quick start module 13 based on the power supply voltage.

[0046] Specifically, in this embodiment, by setting the voltage stabilizing isolation driving module 11, a fast and stable regulated voltage can be provided for the switch tube in the suppression module 12. By setting the fast startup module 13, the operating voltage required for the threshold voltage detection module 14 to work can be quickly generated after the switching power supply is powered on, so that under the working conditions of full input voltage and fast switching, the switch tube in the suppression module 12 can be closed quickly and reliably, thereby achieving the purpose of effectively suppressing the impact current and preventing the current limiting resistor R4 from being burned out.

[0047] Optionally, in this embodiment, the voltage stabilizing isolation driving module 11 includes: a peak holding circuit, a first voltage stabilizing circuit and an isolation driving circuit. The input end of the peak holding circuit is connected to the input bus, the output end of the peak holding circuit is grounded, the input end of the first voltage stabilizing circuit is connected to the peak holding circuit, the output end of the first voltage stabilizing circuit is connected to the input end of the isolation driving circuit, and the output end of the isolation driving circuit is connected to the suppression module 12.

[0048] The peak holding circuit is used to hold the peak value of the bus voltage; the first voltage stabilizing circuit is used to generate a stable voltage for the suppression module 12 to work according to the bus voltage; and the isolation drive circuit is used to perform an isolation operation and output a drive signal to the suppression module 12. Specifically, by setting the peak holding circuit, the stable voltage generated by the first voltage stabilizing circuit can be prevented from fluctuating with the bus voltage.

[0049] In this embodiment, the suppression module 12 includes: a switching circuit and a current limiting circuit; the first end of the switching circuit is connected to the voltage stabilizing isolation drive circuit, and the second end of the switching circuit is connected to the current limiting circuit; the switching circuit is used to control the conduction or closing of the current limiting circuit; the current limiting circuit is used to suppress the impact current when it is turned on.

[0050] In this embodiment, the quick start module 13 includes: a quick charging circuit and a second voltage stabilizing circuit; the input end of the quick charging circuit is connected to the input bus, the output end of the quick charging circuit is connected to the threshold voltage detection module 14, and the second voltage stabilizing circuit is connected to the quick charging circuit; the quick charging circuit is used to provide an operating voltage to the threshold voltage detection module 14 based on the bus voltage; the second voltage stabilizing circuit is used to cooperate with the quick charging circuit to set the charging cut-off voltage.

[0051] In this embodiment, the threshold voltage detection module 14 includes: a threshold monitoring circuit and an isolation circuit; the threshold monitoring circuit is connected to the fast start module 13 and the power supply circuit respectively, and the isolation circuit is connected to the threshold monitoring circuit; the threshold monitoring circuit is used to detect the power supply voltage of the power supply circuit and drive the isolation circuit to output a conduction signal to the voltage stabilizing isolation drive module 11 based on the power supply voltage, and output a shutdown signal to the fast start module 13. Among them, the power supply circuit is a power supply circuit that provides a power supply voltage to the power part IC. Therefore, by monitoring the power supply voltage provided by the power supply circuit, it can be ensured that the switch tube in the suppression module 12 is closed before the power stage circuit works.

[0052] Furthermore, if Figure 1 As shown, the control circuit of the inrush current suppression circuit also includes: a rectifier module 10, the input end of the rectifier module 10 is connected to the AC input signal, and the output end of the rectifier module 10 is connected to the input bus of the switching power supply. The rectifier module 10 is used to rectify the AC input signal to obtain the bus voltage. Among them, the rectifier module 10 includes a rectifier bridge BD1.

[0053] The principle of the control circuit of the rush current suppression circuit of this embodiment is described below with reference to a preferred embodiment.

[0054] Specifically, Figure 2 The present invention provides a preferred embodiment of the control circuit of the impulse current suppression circuit.

[0055] like Figure 2 As shown, in this embodiment, the peak holding circuit includes: a third diode D3 and a fifth capacitor C5; the first voltage stabilizing circuit includes: a first resistor R1 and a first voltage stabilizing tube ZD1; the isolation drive circuit includes: a first capacitor C1, a switching part OT1-B of the optocoupler, a second resistor R2, a second capacitor C2 and a third resistor R3.

[0056] The anode of the third diode D3 is connected to the input bus, the cathode of the third diode D3 is connected to the first end of the fifth capacitor C5 and the first end of the first resistor R1, the second end of the fifth capacitor C5 is grounded, the second end of the first resistor R1 is connected to the cathode of the first voltage regulator tube ZD1, the input end of the switch part OT1-B of the photocoupler and the first end of the first capacitor C1, and the anode of the first voltage regulator tube ZD1 is grounded; the second end of the first capacitor C1 is grounded, the output end of the switch part OT1-B of the photocoupler is connected to the first end of the second resistor R2, the second end of the second resistor R2 is connected to the first end of the second capacitor C2, the first end of the third resistor R3 and the suppression module 12 (that is, the first end of the first switch tube Q1), and the second end of the second capacitor C2 and the second end of the third resistor R3 are grounded.

[0057] In this embodiment, the switch circuit includes: a first switch tube Q1; the current limiting circuit includes: a current limiting resistor R4; the first end of the first switch tube Q1 is connected to the output end of the voltage stabilizing isolation drive circuit, the second end of the first switch tube Q1 is connected to the input end of the current limiting resistor R4, and the third end of the first switch tube Q1 is connected to the output end of the current limiting resistor R4. Optionally, in this embodiment, the first switch tube Q1 can be a MOS tube, wherein the first end of the first switch tube Q1 is the gate of the MOS tube, the second end of the first switch tube Q1 is the drain of the MOS tube, and the third end of the first switch tube Q1 is the source of the MOS tube.

[0058] Specifically, Figure 2 As shown, the AC input signal is rectified by the rectifier bridge BD1, and the bus voltage is sent to the first resistor R1 and the first voltage regulator ZD1, and a fast, stable and stable voltage (i.e., V1 in the figure) is provided to the first switch tube Q1 through the first resistor R1 and the first voltage regulator ZD1. The peak holding circuit composed of the third diode D3 and the fifth capacitor C5 can prevent V1 from fluctuating with the bus voltage. Since the first switch tube Q1 is a voltage-type power device, its operating current is extremely small. Therefore, the resistance values ​​of the first resistor R1 and the third resistor R3 can be appropriately increased, thereby reducing the power consumption of the circuit. However, when increasing the resistance values ​​of the first resistor R1 and the third resistor R3, it is necessary to ensure that V1 is established before the photoelectric coupler is activated when the low voltage input is low.

[0059] The fast charging circuit includes: a sixth resistor R6, a second switch tube Q2, a first diode D1 and a third capacitor C3; the second voltage stabilizing circuit includes: a fifth resistor R5, a second voltage stabilizing tube ZD2 and a fourth capacitor C4.

[0060] The first end of the sixth resistor R6 and the first end of the fifth resistor R5 are connected to the input bus, the second end of the sixth resistor R6 is connected to the first end of the second switch tube Q2, the second end of the second switch tube Q2 is connected to the anode of the first diode D1, the third end of the second switch tube Q2 is connected to the second end of the fifth resistor R5, the cathode of the second voltage-stabilizing tube ZD2 and the first end of the fourth capacitor C4, the anode of the second voltage-stabilizing tube ZD2 is grounded, the second end of the fourth capacitor C4 is grounded, the cathode of the first diode D1 is connected to the first end of the third capacitor C3 and the threshold voltage detection module 14, and the second end of the third capacitor C3 is grounded.

[0061] Optionally, in this embodiment, the second switch tube Q2 can be a MOS tube, wherein the first end of the second switch tube Q2 is the drain of the MOS tube, the second end of the second switch tube Q2 is the source of the MOS tube, and the third end of the second switch tube Q2 is the gate of the MOS tube.

[0062] like Figure 2 As shown, the bus voltage passes through the sixth resistor R6, the second switch tube Q2 and the first diode D1 to quickly charge the third capacitor C3, thereby generating the working voltage required by the threshold voltage detection module 14 (ie Figure 2 The charging cut-off voltage is set by the voltage value of the second voltage regulator tube ZD2, the Vgsth of the second switch tube Q2 and the forward conduction voltage Vf of the first diode D1, that is, VDD=V-Vgsth-Vf.

[0063] In this embodiment, Figure 2 As shown, the threshold monitoring circuit includes: a reference device U1, a second diode D2, a ninth resistor R9 and a tenth resistor R10; the isolation circuit includes: a seventh resistor R7, an eighth resistor R8 and a power-on part OT1-A of the photocoupler.

[0064] The first end of the reference device U1 is connected to the second end of the power-on part OT1-A of the optocoupler, the second end of the reference device U1 is connected to the second end of the ninth resistor R9 and the first end of the tenth resistor R10, the third end of the reference device U1 is grounded, the second end of the tenth resistor R10 is grounded, the first end of the ninth resistor R9 is connected to the power supply circuit and the anode of the second diode D2, and the cathode of the second diode D2 is connected to the cathode of the first diode D1; the first end of the seventh resistor R7 is connected to the quick start module 13 (that is, the cathode of the first diode D1), the second end of the seventh resistor R7 is connected to the first end of the power-on part OT1-A of the optocoupler and the first end of the eighth resistor R8, and the second end of the eighth resistor R8 is grounded.

[0065] Specifically, Figure 2 As shown, the threshold monitoring circuit composed of the reference device U1, the ninth resistor R9 and the tenth resistor R10 can monitor the supply voltage (ie Figure 2The VCC in the circuit is monitored and it is determined whether it has reached the set value (i.e., the preset threshold voltage value). When the voltage of VCC rises to the set value, the reference device U1 is turned on. At this time, the power-on part of the optocoupler is turned on, thereby turning on the switch part OT1-B of the optocoupler, thereby outputting a driving signal to the first switch tube Q1, closing the first switch tube Q1, and short-circuiting the current limiting resistor R4. When the voltage of VCC is higher than the VDD voltage, it is sent to VDD through the second diode D2, thereby turning off the quick start circuit, thereby achieving the purpose of reducing circuit loss.

[0066] In this embodiment, the preset threshold voltage value can be set by the voltage division ratio of the ninth resistor R9 and the tenth resistor R10, wherein the preset threshold voltage value is less than the Vcc-off voltage of the power part IC, thereby ensuring that the first switch tube Q1 is stably and reliably closed before the power circuit works. When the power part starts to work and the first switch tube Q1 is not closed, the current limiting resistor R4 will be burned due to high loss. Once the current limiting resistor R4 is burned, the entire switching power supply will not be able to start again. Therefore, the utility model can stably and reliably close the first switch tube Q1 to short-circuit the current limiting resistor R4 before the power part starts to work by monitoring VCC, thereby avoiding the current limiting resistor R4 from being burned.

[0067] The specific working process is as follows: after AC power is turned on, the AC input signal charges the electrolytic capacitor CE1 through the current limiting resistor R4, so as to achieve the purpose of suppressing the impact current. At the same time, the voltage stabilizing isolation drive module 11 and the fast start module 13 quickly generate the V1 and VDD required by the circuit. After V1 and VDD are generated, the threshold voltage detection module 14 performs threshold voltage monitoring. When VCC rises to the preset threshold voltage value, the first switch tube Q1 is quickly closed to avoid the current limiting resistor R4 from being burned. It should be noted that in this embodiment, the startup time of the circuit can be adjusted according to the limit of the impact current, the input voltage and the capacity of the bus capacitor (i.e., the electrolytic capacitor CE1) to ensure that the first switch tube Q1 can be quickly and reliably closed under the working conditions of full input voltage and fast switching.

[0068] The utility model also provides a switching power supply, which may include: a control circuit of the impact current suppression circuit disclosed in the utility model.

[0069] The above embodiments are only for illustrating the technical concept and features of the utility model, and their purpose is to enable people familiar with the technology to understand the content of the utility model and implement it accordingly, and they cannot limit the protection scope of the utility model. All equivalent changes and modifications made to the scope of the claims of the utility model should fall within the scope of the claims of the utility model.

Claims

1. A control circuit for an inrush current suppression circuit, characterized in that: include: Voltage stabilization isolation drive module, suppression module, fast start module and threshold voltage detection module; The input end of the voltage stabilizing isolation driving module is connected to the input bus of the switching power supply, the output end of the voltage stabilizing isolation driving module is connected to the suppression module, the first end of the fast start module is connected to the input bus, the second end of the fast start module is connected to the first end of the threshold voltage detection module, and the second end of the threshold voltage detection module is connected to the power supply circuit of the power circuit of the switching power supply; The voltage stabilizing isolation driving module generates a stable voltage for the suppression module to work according to the bus voltage of the input bus; The suppression module is used to suppress the inrush current of the switching power supply; The fast start module provides an operating voltage to the threshold voltage detection module based on the bus voltage; The threshold voltage detection module is used to detect the supply voltage of the power supply circuit and output a conduction signal to the voltage stabilizing isolation driving module and a shutdown signal to the fast start module based on the supply voltage.

2. The control circuit of the inrush current suppression circuit according to claim 1, characterized in that: The voltage stabilizing isolation driving module includes: a peak holding circuit, a first voltage stabilizing circuit and an isolation driving circuit; The input end of the peak hold circuit is connected to the input bus, the output end of the peak hold circuit is grounded, the input end of the first voltage stabilizing circuit is connected to the peak hold circuit, the output end of the first voltage stabilizing circuit is connected to the input end of the isolation drive circuit, and the output end of the isolation drive circuit is connected to the suppression module; The peak holding circuit is used to hold the peak value of the bus voltage; The first voltage stabilizing circuit is used to generate a stable voltage for the suppression module to work according to the bus voltage; The isolation driving circuit is used to perform an isolation operation and output a driving signal to the suppression module.

3. The control circuit of the inrush current suppression circuit according to claim 2, characterized in that: The peak hold circuit includes: a third diode and a fifth capacitor; the first voltage stabilizing circuit includes: a first resistor and a first voltage stabilizing tube; the isolation drive circuit includes: a first capacitor, a switch portion of a photocoupler, a second resistor, a second capacitor and a third resistor; The anode of the third diode is connected to the input bus, the cathode of the third diode is connected to the first end of the fifth capacitor and the first end of the first resistor, the second end of the fifth capacitor is grounded, the second end of the first resistor is connected to the cathode of the first voltage regulator tube, the input end of the switch part of the photocoupler, and the first end of the first capacitor, and the anode of the first voltage regulator tube is grounded; The second end of the first capacitor is grounded, the output end of the switch part of the optocoupler is connected to the first end of the second resistor, the second end of the second resistor is connected to the first end of the second capacitor, the first end of the third resistor and the suppression module, and the second end of the second capacitor and the second end of the third resistor are grounded.

4. The control circuit of the inrush current suppression circuit according to claim 1, wherein: The suppression module includes: a switching circuit and a current limiting circuit; The first end of the switch circuit is connected to the voltage stabilizing isolation driving module, and the second end of the switch circuit is connected to the current limiting circuit; The switch circuit is used to control the on or off of the current limiting circuit; the current limiting circuit is used to suppress the inrush current when it is on.

5. The control circuit of the inrush current suppression circuit according to claim 4, characterized in that: The switch circuit includes: a first switch tube; the current limiting circuit includes: a current limiting resistor; The first end of the first switch tube is connected to the output end of the voltage stabilizing isolation driving module, the second end of the first switch tube is connected to the input end of the current limiting resistor, and the third end of the first switch tube is connected to the output end of the current limiting resistor.

6. The control circuit of the inrush current suppression circuit according to claim 1, characterized in that: The fast start module includes: a fast charging circuit and a second voltage stabilizing circuit; The input end of the fast charging circuit is connected to the input bus, the output end of the fast charging circuit is connected to the threshold voltage detection module, and the second voltage stabilizing circuit is connected to the fast charging circuit; The fast charging circuit is used to provide an operating voltage to the threshold voltage detection module based on the bus voltage; The second voltage stabilizing circuit is used to cooperate with the fast charging circuit to set a charging cut-off voltage.

7. The control circuit of the inrush current suppression circuit according to claim 6, characterized in that: The fast charging circuit includes: a sixth resistor, a second switching tube, a first diode and a third capacitor; the second voltage stabilizing circuit includes: a fifth resistor, a second voltage stabilizing tube and a fourth capacitor; The first end of the sixth resistor and the first end of the fifth resistor are connected to the input bus, the second end of the sixth resistor is connected to the first end of the second switching tube, the second end of the second switching tube is connected to the anode of the first diode, the third end of the second switching tube is connected to the second end of the fifth resistor, the cathode of the second voltage-stabilizing tube and the first end of the fourth capacitor, the anode of the second voltage-stabilizing tube is grounded, the second end of the fourth capacitor is grounded, the cathode of the first diode is connected to the first end of the third capacitor and the threshold voltage detection module, and the second end of the third capacitor is grounded.

8. The control circuit of the inrush current suppression circuit according to claim 7, characterized in that: The threshold voltage detection module includes: a threshold monitoring circuit and an isolation circuit; The threshold monitoring circuit is connected to the quick start module and the power supply circuit respectively, and the isolation circuit is connected to the threshold monitoring circuit; The threshold monitoring circuit is used to detect the supply voltage of the power supply circuit and drive the isolation circuit to output a conduction signal to the voltage stabilizing isolation drive module and output a shutdown signal to the fast start module based on the supply voltage.

9. The control circuit of the inrush current suppression circuit according to claim 8, characterized in that: The threshold monitoring circuit includes: a reference device, a second diode, a ninth resistor and a tenth resistor; the isolation circuit includes: a seventh resistor, an eighth resistor and a power-on part of a photoelectric coupler; The first end of the reference device is connected to the second end of the power supply portion of the photocoupler, the second end of the reference device is connected to the second end of the ninth resistor and the first end of the tenth resistor, the third end of the reference device is grounded, the second end of the tenth resistor is grounded, the first end of the ninth resistor is connected to the power supply circuit and the anode of the second diode, and the cathode of the second diode is connected to the cathode of the first diode; A first end of the seventh resistor is connected to the fast start module, a second end of the seventh resistor is connected to a first end of the power supply portion of the photocoupler and a first end of the eighth resistor, and a second end of the eighth resistor is grounded.

10. A switching power supply, characterized in that: include: The control circuit of the inrush current suppression circuit according to any one of claims 1 to 9.

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