Low-side drive anti-inrush continuous current circuit and electronic device

Abstract

The application provides a low-side driving anti-backflow continuous current circuit and electronic equipment. The low-side driving anti-backflow continuous current circuit comprises an inductive load, an anti-backflow sub-circuit and a driving sub-circuit. The first end of the inductive load is electrically connected with a battery voltage source, and the second end of the inductive load is electrically connected with a low-side driving switch. The first end of the anti-backflow sub-circuit is electrically connected with the second end of the inductive load, and the anti-backflow sub-circuit is used for blocking the voltage generated by the discharge of the inductive load when the battery voltage source does not provide voltage. The driving sub-circuit is used for driving the anti-backflow sub-circuit. By arranging the driving sub-circuit and the anti-backflow sub-circuit, the purpose of driving the anti-backflow sub-circuit by the driving sub-circuit is achieved. Meanwhile, the anti-backflow sub-circuit can block the voltage generated by the discharge of the inductive load when the battery voltage source does not provide voltage, thereby solving the problem of low working efficiency of the anti-backflow circuit in the prior art.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of low-side driving circuit, in particular to a low-side driving anti-backflow freewheeling circuit and electronic equipment. BACKGROUND

[0002] The existing low-side freewheeling circuit is generally directly freewheeling the low-side power output to the battery voltage position through a freewheeling diode.

[0003] The disadvantage of the scheme is that when the low-side load is an inductive load, if the load high side is powered by a battery instead of the high-side output of the controller, after the controller powers off, the battery voltage will flow back to the board through the inductive load and the freewheeling diode, causing the controller to fail to power off normally, and even burn out the controller, that is, the working efficiency of the anti-backflow circuit of the existing scheme is low. SUMMARY

[0004] The main purpose of the present application is to provide a low-side driving anti-backflow freewheeling circuit and electronic equipment to at least solve the problem of low working efficiency of the anti-backflow circuit of the existing scheme.

[0005] In order to achieve the above-mentioned purpose, according to one aspect of the present application, a low-side driving anti-backflow freewheeling circuit is provided, which comprises an inductive load, an anti-backflow sub-circuit and a driving sub-circuit; the inductive load has a first end and a second end, the first end of the inductive load is used for electrically connecting with a battery voltage source, and the second end of the inductive load is used for electrically connecting with a low-side driving switch; the anti-backflow sub-circuit has a first end, a second end and a driving end, the first end of the anti-backflow sub-circuit is electrically connected with the second end of the inductive load, and the anti-backflow sub-circuit is used for blocking the voltage generated by discharging of the inductive load when the battery voltage source does not provide voltage; the driving sub-circuit is electrically connected with the second end of the anti-backflow sub-circuit and the driving end of the anti-backflow sub-circuit respectively, and the driving sub-circuit is used for driving the anti-backflow sub-circuit.

[0006] Optionally, the driving sub-circuit comprises a square wave signal generating sub-circuit and a charge pump boosting sub-circuit, the square wave signal generating sub-circuit has an output end for generating a square wave signal, the charge pump boosting sub-circuit has a first input end, a second input end and an output end, the first input end of the charge pump boosting sub-circuit is electrically connected with the second end of the anti-backflow sub-circuit, the second input end of the charge pump boosting sub-circuit is electrically connected with the output end of the square wave signal generating sub-circuit, the output end of the charge pump boosting sub-circuit is electrically connected with the driving end of the anti-backflow sub-circuit, and the charge pump boosting sub-circuit is configured to amplify the voltage provided by the battery voltage source according to the square wave signal to drive the anti-backflow sub-circuit in the case that the battery voltage source provides voltage.

[0007] Optionally, the anti-backflow sub-circuit comprises an anti-backflow transistor and a freewheeling diode, the drain of the anti-backflow transistor is electrically connected with the negative electrode of the freewheeling diode, the gate of the anti-backflow transistor is electrically connected with the output end of the charge pump boosting sub-circuit, the source of the anti-backflow transistor is electrically connected with the first input end of the charge pump boosting sub-circuit, and the positive electrode of the freewheeling diode is electrically connected with the second end of the inductive load.

[0008] Optionally, the square wave signal generating sub-circuit comprises a flip-flop, a first capacitor module and a first resistor module, the power supply end of the flip-flop is electrically connected with the first end of the first voltage source, the input end of the flip-flop is electrically connected with the first end of the first capacitor module and the first end of the first resistor module respectively, the second end of the first resistor module is electrically connected with the output end of the flip-flop, the output end of the flip-flop is also electrically connected with the second input end of the charge pump boosting sub-circuit, and the ground end of the flip-flop, the second end of the first capacitor module and the second end of the first voltage source are grounded respectively.

[0009] Optionally, the charge pump boosting sub-circuit comprises a boosting module, a first anti-backflow module, a second anti-backflow module, a voltage dividing module and a filtering module, the boosting module is configured to boost the square wave signal, the first end of the boosting module is electrically connected with the output end of the flip-flop of the square wave signal generating sub-circuit, the second end of the boosting module is electrically connected with the negative electrode of the first anti-backflow module and the positive electrode of the second anti-backflow module respectively, the third end of the boosting module is electrically connected with the positive electrode of the first anti-backflow module, the positive electrode of the first anti-backflow module is electrically connected with the first end of the second voltage source and the second end of the anti-backflow sub-circuit respectively, the negative electrode of the second anti-backflow module is electrically connected with the input end of the voltage dividing module and the first end of the filtering module respectively, the output end of the voltage dividing module is electrically connected with the gate of the anti-backflow transistor of the anti-backflow sub-circuit, and the second end of the filtering module, the ground end of the voltage dividing module and the second end of the second voltage source are grounded respectively.

[0010] Optionally, the first anti-inverted flow module and the second anti-inverted flow module are both diode structures.

[0011] Optionally, the voltage boosting module comprises a second resistance module, a third resistance module, a fourth resistance module, a triode and a second capacitor module, the first end of the second resistance module is electrically connected with the output end of the flip-flop of the square wave signal generation sub-circuit, the base of the triode is electrically connected with the second end of the second resistance module and the first end of the third resistance module respectively, the collector of the triode is electrically connected with the first end of the fourth resistance module and the first end of the second capacitor module respectively, the second end of the second capacitor module is electrically connected with the negative pole of the first anti-inverted flow module and the positive pole of the second anti-inverted flow module respectively, the positive pole of the first anti-inverted flow module is electrically connected with the first end of the second voltage source, the second end of the fourth resistance module and the second end of the anti-inverted flow sub-circuit respectively, the negative pole of the second anti-inverted flow module is electrically connected with the input end of the voltage division module and the first end of the filter module respectively, the output end of the voltage division module is electrically connected with the gate of the anti-inverted flow transistor of the anti-inverted flow sub-circuit, and the collector of the triode and the second end of the third resistance module are grounded respectively.

[0012] Optionally, the voltage division module comprises a fifth resistance module and a sixth resistance module, the first end of the fifth resistance module is electrically connected with the negative pole of the second anti-inverted flow module, the second end of the fifth resistance module is electrically connected with the first end of the sixth resistance module and the gate of the anti-inverted flow transistor of the anti-inverted flow sub-circuit respectively, and the second end of the sixth resistance module is grounded.

[0013] Optionally, the filter module is a third capacitor module.

[0014] According to another aspect of the present application, an electronic device is provided, which comprises any one of the low-side driving anti-inverted flow continuous current circuits.

[0015] By means of the technical scheme of the present application, the driving sub-circuit and the anti-inverted flow sub-circuit are arranged, so as to realize the purpose that the driving sub-circuit drives the anti-inverted flow sub-circuit, and meanwhile, in the case that the battery voltage source does not provide voltage, the anti-inverted flow sub-circuit can block the voltage generated by the inductive load discharging, thereby solving the problem of low working efficiency of the anti-inverted flow circuit in the prior art. BRIEF DESCRIPTION OF DRAWINGS

[0016] The drawings constituting a part of the specification of the present application are used to provide further understanding of the present application, the illustrative embodiments of the present application and the description thereof are used to explain the present application, and do not constitute improper limitation on the present application. In the drawings:

[0017] Figure 1A first schematic diagram of a low-side driving anti-inrush continuous current circuit provided in an embodiment of the present application is shown.

[0018] Figure 2 A second schematic diagram of a low-side driving anti-inrush continuous current circuit provided in an embodiment of the present application is shown.

[0019] Figure 3 A third schematic diagram of a low-side driving anti-inrush continuous current circuit provided in an embodiment of the present application is shown.

[0020] Figure 4 A schematic diagram of an anti-inrush sub-circuit provided in an embodiment of the present application is shown.

[0021] Figure 5 A schematic diagram of a square wave signal generation sub-circuit provided in an embodiment of the present application is shown.

[0022] Figure 6 A schematic diagram of a voltage division module provided in an embodiment of the present application is shown.

[0023] Among the above figures, the following reference signs are included:

[0024] 100, anti-inrush sub-circuit; 200, driving sub-circuit; 210, square wave signal generation sub-circuit; 220, charge pump boosting sub-circuit; 221, boosting module; 222, voltage division module. DETAILED DESCRIPTION

[0025] It should be noted that the embodiments and features in the present application can be combined with each other without conflict. The technical solutions in the embodiments of the present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0026] In order to enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments. Obviously, the described embodiments are only a part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should belong to the scope of protection of the present application.

[0027] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and in the above drawings are used to distinguish similar objects, and do not necessarily have to be used to describe a specific order or sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not have to be limited to only those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0028] As introduced in the background, the existing low-side freewheeling circuit is generally simply directly freewheeling the low-side power output to the position of the battery voltage in the board through a freewheeling diode. The disadvantage of this scheme is that when the low-side load is an inductive load, if the load high side is powered by a battery instead of the high-side output of the controller, after the controller is powered off, the battery voltage will flow back to the board through the inductive load and the freewheeling diode, resulting in that the controller cannot be normally powered off, and even the controller is burned out, that is, the working efficiency of the existing anti-backflow circuit is low. To solve the problem of low working efficiency of the existing anti-backflow circuit, the embodiments of the present application provide a low-side drive anti-backflow freewheeling circuit and an electronic device.

[0029] 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.

[0030] The embodiments of the present application provide a low-side drive anti-backflow freewheeling circuit, as shown in Figure 1 , Figure 2 and Figure 3 , the low-side drive anti-backflow freewheeling circuit includes an inductive load L1, an anti-backflow sub-circuit 100 and a drive sub-circuit 200; the inductive load L1 has a first end and a second end, the first end of the inductive load L1 is used to be electrically connected with a battery voltage source VCC, and the second end of the inductive load L1 is used to be electrically connected with a low-side drive switch DQ; the anti-backflow sub-circuit 100 has a first end, a second end and a drive end, the first end of the anti-backflow sub-circuit 100 is electrically connected with the second end of the inductive load L1, and the anti-backflow sub-circuit 100 is used to block the voltage generated by the discharge of the inductive load L1 when the battery voltage source VCC does not provide voltage; the drive sub-circuit 200 is electrically connected with the second end of the anti-backflow sub-circuit 100 and the drive end of the anti-backflow sub-circuit 100 respectively, and the drive sub-circuit 200 is used to drive the anti-backflow sub-circuit 100.

[0031] The low-side driving anti-inrush freewheeling circuit has the advantages that the driving sub-circuit and the anti-inrush sub-circuit are arranged, so that the driving sub-circuit drives the anti-inrush sub-circuit, and the anti-inrush sub-circuit can block the voltage generated by the discharge of the inductive load in the case that the battery voltage source does not provide voltage, thereby solving the problem of low working efficiency of the anti-inrush circuit in the prior art.

[0032] Meanwhile, since each device is a discrete structure, compared with various assembled devices in the prior art, the device is cheaper, thereby reducing the total cost of purchasing devices.

[0033] In an embodiment of the present application, as shown in Figure 1 , Figure 2 and Figure 3 , the driving sub-circuit 200 includes a square wave signal generation sub-circuit 210 and a charge pump voltage boosting sub-circuit 220, the square wave signal generation sub-circuit 210 has an output end, the output end of the square wave signal generation sub-circuit 210 is used to generate a square wave signal, the charge pump voltage boosting sub-circuit 220 has a first input end, a second input end and an output end, the first input end of the charge pump voltage boosting sub-circuit 220 is electrically connected with the second end of the anti-inrush sub-circuit 100, the second input end of the charge pump voltage boosting sub-circuit 220 is electrically connected with the output end of the square wave signal generation sub-circuit 210, the output end of the charge pump voltage boosting sub-circuit 220 is electrically connected with the driving end of the anti-inrush sub-circuit 100, and the charge pump voltage boosting sub-circuit 220 is used to amplify the voltage provided by the battery voltage source VCC according to the square wave signal, so as to drive the anti-inrush sub-circuit 100 in the case that the battery voltage source VCC provides voltage.

[0034] Specifically, the square wave signal generation sub-circuit and the charge pump voltage boosting sub-circuit are arranged, so that the voltage provided by the battery voltage source VCC is amplified according to the square wave signal generated by the square wave signal generation sub-circuit, so as to drive the anti-inrush sub-circuit in the case that the battery voltage source VCC provides voltage.

[0035] In an embodiment of the present application, as shown in Figure 2 , Figure 3 and Figure 4 , the anti-inrush sub-circuit 100 includes an anti-inrush transistor M1 and a freewheeling diode D3, the drain of the anti-inrush transistor M1 is electrically connected with the negative electrode of the freewheeling diode D3, the gate of the anti-inrush transistor M1 is electrically connected with the output end of the charge pump voltage boosting sub-circuit 220, the source of the anti-inrush transistor M1 is electrically connected with the first input end of the charge pump voltage boosting sub-circuit 220, and the positive electrode of the freewheeling diode D3 is electrically connected with the second end of the inductive load L1.

[0036] The anti-inrush transistor is an NMOS transistor structure. The NMOS transistor structure can prevent current from flowing back after the controller is powered off, and does not affect normal low-side continuous current when powered on.

[0037] In an embodiment of the present application, as shown in Figure 2 、 Figure 3 and Figure 5 , the square wave signal generation sub-circuit 210 includes a flip-flop U1, a first capacitor module C3 and a first resistor module R1. The power supply end VCC1 of the flip-flop U1 is electrically connected to the first end of the first voltage source V1. The input end A of the flip-flop U1 is electrically connected to the first end of the first capacitor module C3 and the first end of the first resistor module R1 respectively. The second end of the first resistor module R1 is electrically connected to the output end of the flip-flop U1. The output end Y of the flip-flop U1 is also electrically connected to the second input end of the charge pump voltage boosting sub-circuit 220. The ground end AGND of the flip-flop U1, the second end of the first capacitor module C3 and the second end of the first voltage source V1 are grounded respectively.

[0038] Specifically, in the initial state, the voltage of the input end A of the flip-flop U1 is lower than the trigger threshold value, the level of the output end Y of the flip-flop U1 is high, the voltage of the output end Y of the flip-flop U1 charges the first capacitor module C3 through the first resistor module R1 and makes the voltage of the first capacitor module C3 higher than the trigger threshold value, the level of the output end Y of the flip-flop U1 becomes low, and the input end A of the flip-flop U1 is discharged to low through R7, so that the output end of the flip-flop U1 generates a periodic square wave signal. The flip-flop U1 is a Schmitt trigger, and the model number is SN74LVC1G14.

[0039] In an embodiment of the present application, as shown in Figure 2 and Figure 3As shown, the charge pump voltage boosting sub-circuit 220 includes a voltage boosting module 221, a first backflow prevention module D1, a second backflow prevention module D2, a voltage dividing module 222, and a filter module C2. The voltage boosting module 221 is configured to boost the square wave signal. The first end of the voltage boosting module 221 is electrically connected to the output end of the flip-flop U1 of the square wave signal generation sub-circuit 210. The second end of the voltage boosting module 221 is electrically connected to the negative electrode of the first backflow prevention module D1 and the positive electrode of the second backflow prevention module D2, respectively. The third end of the voltage boosting module 221 is electrically connected to the positive electrode of the first backflow prevention module D1. The positive electrode of the first backflow prevention module D1 is electrically connected to the first end of the second voltage source V2 and the second end of the backflow prevention sub-circuit 100, respectively. The negative electrode of the second backflow prevention module D2 is electrically connected to the input end of the voltage dividing module 222 and the first end of the filter module C2, respectively. The output end of the voltage dividing module 222 is electrically connected to the gate of the backflow prevention transistor M1 of the backflow prevention sub-circuit 100. The second end of the filter module C2, the ground end of the voltage dividing module 222, and the second end of the second voltage source V2 are grounded, respectively.

[0040] Specifically, after the square wave signal is input into the triode Q1, the C1 and the connection end of Q1 are periodically grounded and suspended. When Q1 is turned on, the voltage at the upper end of C1 (i.e., the first end) is 24V, and the voltage at the lower end (i.e., the second end) is 0V. When Q1 is turned off, the voltage at the lower end becomes 24V. Because the voltage across the capacitor cannot change abruptly, the voltage at the upper end of C1 becomes 48V. The upper end of C1 generates a periodic 24V-48V voltage signal. Because D2 exists, energy can only flow forward through C2 to generate a stable 48V voltage after being filtered, and the voltage is driven to the backflow prevention transistor M1 after being divided.

[0041] In an embodiment of the present application, the first backflow prevention module and the second backflow prevention module are both diode structures. The unidirectional conduction of the diode is utilized.

[0042] In an embodiment of the present application, as Figure 2 and Figure 3As shown, the above-mentioned boost module 221 includes a second resistance module R2, a third resistance module R3, a fourth resistance module R4, a triode Q1 and a second capacitor module C1, a first end of the second resistance module R2 is electrically connected with an output end of the flip-flop U1 of the square wave signal generation sub-circuit 210, a base of the triode Q1 is electrically connected with a second end of the second resistance module R2 and a first end of the third resistance module R3 respectively, a collector of the triode Q1 is electrically connected with a first end of the fourth resistance module R4 and a first end of the second capacitor module C1 respectively, a second end of the second capacitor module C1 is electrically connected with a negative pole of the first anti-inrush module D1 and a positive pole of the second anti-inrush module D2 respectively, a positive pole of the first anti-inrush module D1 is electrically connected with a first end of the second voltage source V2, a second end of the fourth resistance module R4 and a second end of the anti-inrush sub-circuit 100 respectively, a negative pole of the second anti-inrush module D2 is electrically connected with an input end of the voltage division module 222 and a first end of the filter module C2 respectively, an output end of the voltage division module 222 is electrically connected with a gate of the anti-inrush transistor M1 of the anti-inrush sub-circuit 100, the collector of the triode Q1 and a second end of the third resistance module R3 are grounded respectively.

[0043] Specifically, after the square wave signal is input into the triode Q1, the C1 and the Q1 connection end will be grounded and suspended periodically, when the Q1 is turned on, the upper end voltage of the C1 is 24V, and the lower end voltage is 0V, when the Q1 is cut off, the lower end voltage becomes 24V, because the voltage across the capacitor cannot be suddenly changed, the upper end voltage of the C1 becomes 48V, the upper end of the C1 generates a periodic 24V-48V voltage signal, because the D2 exists, the energy can only flow forward through the C2 filter to generate a stable 48V voltage, and the anti-inrush transistor M1 is driven after voltage division.

[0044] In an embodiment of the present application, as shown in Figure 2 and Figure 6 As shown, the above-mentioned voltage division module 222 includes a fifth resistance module R5 and a sixth resistance module R6, a first end of the fifth resistance module R5 is electrically connected with a negative pole of the second anti-inrush module D2, a second end of the fifth resistance module R5 is electrically connected with a first end of the sixth resistance module R6 and a gate of the anti-inrush transistor M1 of the anti-inrush sub-circuit 100 respectively, a second end of the sixth resistance module R6 is grounded. As shown in Figure 2 It further includes a seventh resistance module R7, the connection mode is as shown in Figure 2 R5 and R6 are used to divide the voltage after voltage boosting to prevent the MOS transistor M1 from being damaged by too high voltage.

[0045] When the operator powers on the controller, the Schmitt trigger generates a periodic square wave signal as the excitation of the charge pump voltage boosting subcircuit, generates a high voltage at the gate of the NMOS and turns on the MOS, and when the low-side drive is turned off, L1 flows through the NMOS and D3 to the 24V inside the charge pump voltage boosting subcircuit.

[0046] When the controller is powered off, the 5V signal drops to zero (here, the 5V signal drop to zero is used to describe the case that the entire circuit does not work after the product is powered off), the voltage in the 24V charge pump voltage boosting subcircuit drops to zero, the charge pump voltage boosting subcircuit stops working, and the NMOS is turned off. The principle is the principle of a typical low-side freewheeling circuit. When the product drives an inductive load actuator, if no freewheeling circuit is added, the reverse voltage generated when the low-side is turned off will break the circuit. The controller is a device in a product that includes a controller and a low-side drive anti-inrush freewheeling circuit.

[0047] In an embodiment of the present application, the above-mentioned filtering module is a third capacitor module. Thus, a capacitor is used for filtering.

[0048] The present application also provides an electronic device comprising any one of the above-mentioned low-side drive anti-inrush freewheeling circuits.

[0049] By setting the driving subcircuit and the anti-inrush subcircuit, the driving subcircuit drives the anti-inrush subcircuit, and at the same time, in the case that the battery voltage source does not provide voltage, the anti-inrush subcircuit can block the voltage generated by the discharge of the above-mentioned inductive load, thereby solving the problem of low working efficiency of the anti-inrush circuit of the prior art.

[0050] The adaptive low-side drive anti-inrush freewheeling is realized without occupying the pin of the single-chip microcomputer, the freewheeling problem of the low-side drive inductive load is solved, and the problem of abnormal power-off of the controller caused by the battery voltage flowing back to the controller through the freewheeling circuit after the controller is powered off is prevented.

[0051] When the present application is used, if the load high side is powered by a battery instead of the high side output of the controller when the low-side load is an inductive load, the current will not flow back to the controller even after the controller is powered off.

[0052] It should be noted that the above-mentioned electrical connection can be direct electrical connection or indirect electrical connection. Direct electrical connection means that two devices are directly connected, and indirect electrical connection means that A and B connected are connected with other similar capacitors, resistors, etc.

[0053] It should also be noted that the terms "comprising", "comprises" or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but can also include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element preceded by "comprises a" does not, without more constraints, foreclose the existence of additional identical elements in the process, method, article, or apparatus that comprises the element.

[0054] From the above description, it can be seen that the above-mentioned embodiments of the present application achieve the following technical effects:

[0055] 1) The low-side drive anti-inrush continuous current circuit of the present application sets the driving sub-circuit and the anti-inrush sub-circuit to achieve the purpose of driving the anti-inrush sub-circuit by the driving sub-circuit, and in the case that the battery voltage source does not provide voltage, the anti-inrush sub-circuit can block the voltage generated by the discharge of the inductive load, thereby solving the problem of low working efficiency of the anti-inrush circuit of the prior art.

[0056] 2) The electronic device of the present application sets the driving sub-circuit and the anti-inrush sub-circuit to achieve the purpose of driving the anti-inrush sub-circuit by the driving sub-circuit, and in the case that the battery voltage source does not provide voltage, the anti-inrush sub-circuit can block the voltage generated by the discharge of the inductive load, thereby solving the problem of low working efficiency of the anti-inrush circuit of the prior art.

[0057] The above only describes the preferred embodiments of the present application and is not intended to limit the present application. For those skilled in the art, the present application can have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A low-side driven anti-backflow freewheeling circuit, characterized in that, include: An inductive load has a first terminal and a second terminal, wherein the first terminal of the inductive load is used to be electrically connected to a battery voltage source, and the second terminal of the inductive load is used to be electrically connected to a low-side drive switch. An anti-backflow sub-circuit has a first terminal, a second terminal, and a driving terminal. The first terminal of the anti-backflow sub-circuit is electrically connected to the second terminal of the inductive load. The anti-backflow sub-circuit is used to block the voltage generated by the discharge of the inductive load when the battery voltage source does not provide voltage. A driving sub-circuit is provided, which is electrically connected to both the second terminal and the driving terminal of the anti-backflow sub-circuit. The driving sub-circuit is used to drive the anti-backflow sub-circuit. The driving sub-circuit includes: a square wave signal generation sub-circuit with an output terminal, the output terminal of which is used to generate a square wave signal; and a charge pump boost sub-circuit with a first input terminal, a second input terminal, and an output terminal. The first input terminal of the charge pump boost sub-circuit is electrically connected to the second terminal of the anti-backflow sub-circuit, the second input terminal of the charge pump boost sub-circuit is electrically connected to the output terminal of the square wave signal generation sub-circuit, and the output terminal of the charge pump boost sub-circuit is electrically connected to the driving terminal of the anti-backflow sub-circuit. The charge pump boost sub-circuit is used to amplify the voltage provided by the battery voltage source according to the square wave signal, so as to drive the anti-backflow sub-circuit when the battery voltage source provides voltage. The charge pump boost sub-circuit includes: a boost module, a first anti-backflow module, a second anti-backflow module, a voltage divider module, and a filter module. The boost module is used to boost the square wave signal. The first terminal of the boost module is electrically connected to the output terminal of the trigger of the square wave signal generation sub-circuit. The second terminal of the boost module is electrically connected to the negative terminal of the first anti-backflow module and the positive terminal of the second anti-backflow module. The third terminal of the boost module is electrically connected to the positive terminal of the first anti-backflow module. The positive terminal of the first anti-backflow module is electrically connected to the first terminal of the second voltage source and the second terminal of the anti-backflow sub-circuit. The negative terminal of the second anti-backflow module is electrically connected to the input terminal of the voltage divider module and the first terminal of the filter module. The output terminal of the voltage divider module is electrically connected to the gate of the anti-backflow transistor of the anti-backflow sub-circuit. The second terminal of the filter module, the ground terminal of the voltage divider module, and the second terminal of the second voltage source are all grounded.

2. The low-side drive anti-backflow freewheeling circuit according to claim 1, characterized in that, The backflow prevention sub-circuit includes a backflow prevention transistor and a freewheeling diode. The drain of the backflow prevention transistor is electrically connected to the negative terminal of the freewheeling diode. The gate of the backflow prevention transistor is electrically connected to the output terminal of the charge pump boost sub-circuit. The source of the backflow prevention transistor is electrically connected to the first input terminal of the charge pump boost sub-circuit. The positive terminal of the freewheeling diode is electrically connected to the second terminal of the inductive load.

3. The low-side drive anti-backflow freewheeling circuit according to claim 1, characterized in that, The square wave signal generation sub-circuit includes: a trigger, a first capacitor module, and a first resistor module. The power supply terminal of the trigger is electrically connected to the first terminal of the first voltage source. The input terminal of the trigger is electrically connected to the first terminal of the first capacitor module and the first terminal of the first resistor module, respectively. The second terminal of the first resistor module is electrically connected to the output terminal of the trigger. The output terminal of the trigger is also electrically connected to the second input terminal of the charge pump boost sub-circuit. The ground terminal of the trigger, the second terminal of the first capacitor module, and the second terminal of the first voltage source are respectively grounded.

4. The low-side drive anti-backflow freewheeling circuit according to claim 1, characterized in that, Both the first anti-backflow module and the second anti-backflow module are diode structures.

5. The low-side drive anti-backflow freewheeling circuit according to claim 1, characterized in that, The boost module includes: a second resistor module, a third resistor module, a fourth resistor module, a transistor, and a second capacitor module. The first terminal of the second resistor module is electrically connected to the output terminal of the trigger of the square wave signal generation sub-circuit. The base of the transistor is electrically connected to the second terminal of the second resistor module and the first terminal of the third resistor module. The collector of the transistor is electrically connected to the first terminal of the fourth resistor module and the first terminal of the second capacitor module. The second terminal of the second capacitor module is electrically connected to the negative terminal of the first anti-backflow module and the positive terminal of the second anti-backflow module. The positive terminal of the first anti-backflow module is electrically connected to the first terminal of the second voltage source, the second terminal of the fourth resistor module, and the second terminal of the anti-backflow sub-circuit. The negative terminal of the second anti-backflow module is electrically connected to the input terminal of the voltage divider module and the first terminal of the filter module. The output terminal of the voltage divider module is electrically connected to the gate of the anti-backflow transistor of the anti-backflow sub-circuit. The collector of the transistor and the second terminal of the third resistor module are grounded.

6. The low-side drive anti-backflow freewheeling circuit according to claim 5, characterized in that, The voltage divider module includes a fifth resistor module and a sixth resistor module. The first end of the fifth resistor module is electrically connected to the negative terminal of the second anti-backflow module. The second end of the fifth resistor module is electrically connected to the first end of the sixth resistor module and the gate of the anti-backflow transistor of the anti-backflow sub-circuit. The second end of the sixth resistor module is grounded.

7. The low-side drive anti-backflow freewheeling circuit according to claim 1, characterized in that, The filtering module is the third capacitor module.

8. An electronic device, characterized in that, include: The low-side drive anti-backflow freewheeling circuit according to any one of claims 1 to 7.

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