Driving circuit for a single-phase load and engineering machine

Abstract

The utility model provides a kind of single inductive load's drive circuit and engineering machinery, the drive circuit includes: switching circuit, switching circuit includes field effect tube, for the conduction / cutoff of driving field effect tube according to control signal, realize the drive of single inductive load;Overcurrent protection circuit, for when driving current exceeds current threshold, conduction, to drive field effect tube cutoff;Voltage sampling circuit, for collecting the driving voltage of single inductive load, and when driving voltage exceeds voltage threshold, drive the field effect tube cutoff of switching circuit;Clamp circuit, for the voltage input single-chip microcontroller is clamped within first set voltage.The utility model only by increasing a small amount of component design, can realize the overcurrent protection of single inductive load drive in hardware level, improve the safety and reliability of the drive of single inductive load, and sampling voltage value will mutate transition when overcurrent occurs, software can more accurately, timely detect fault and make relevant diagnosis.

Description

Technical Field

[0001] This utility model relates to the field of power electronics technology, specifically to a drive circuit for a single inductive load and engineering machinery. Background Technology

[0002] When a single inductive load is switched on or off, a large instantaneous current is generated. This instantaneous current produces a back electromotive force in the circuit, causing the voltage to rise or fall momentarily, which may damage the circuit. Currently, the circuit is typically disconnected by monitoring the source voltage of the MOSFET and, upon detecting a dangerous condition, by having the microcontroller control the MOSFET to turn off.

[0003] In the above methods, overcurrent protection for a single inductive load is a software-level protection. The microcontroller samples the voltage at the source of the MOSFET to monitor the current in the circuit. When the microcontroller detects excessive current, it controls the drive circuit of the single inductive load to shut down. If the microcontroller fails to control the MOSFET to cut off in time, there may be quality risks such as component damage. Protection based solely on software has low reliability. Utility Model Content

[0004] To solve the above-mentioned technical problems, this utility model provides a driving circuit for a single inductive load.

[0005] This utility model also proposes an engineering machinery.

[0006] The technical solution adopted in this utility model is as follows:

[0007] This invention proposes a driving circuit for a single inductive load, comprising: a switching circuit, including a field-effect transistor (FET), one end of which is connected to a microcontroller control signal terminal, and the other end of which is connected to the driving terminal of the single inductive load, for driving the FET to turn on / off according to the control signal to drive the single inductive load; an overcurrent protection circuit, one end of which is connected to the driving current terminal, and the other end of which is connected to the switching circuit, for turning on when the driving current exceeds a current threshold to drive the FET of the switching circuit to turn off; a voltage sampling circuit, connected to the driving current terminal and the FET, for acquiring the driving voltage of the single inductive load, and driving the FET of the switching circuit to turn off when the driving voltage exceeds a voltage threshold; and a clamping circuit, connected to the microcontroller input port, for clamping the voltage input to the microcontroller within a first set voltage.

[0008] The driving circuit for the single inductive load described above in this utility model also has the following additional technical features:

[0009] Specifically, the switching circuit includes: a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, a seventh resistor, a first capacitor, a second capacitor, a first diode, a first N-type transistor, a second P-type transistor, a third N-type transistor, a fourth P-type transistor, and a first field-effect transistor (FET), wherein the first FET is an N-channel enhancement-mode FET; wherein, one end of the first resistor is connected to the microcontroller control signal terminal, the other end of the first resistor is connected to one end of the second resistor, and the other end of the second resistor is connected to the power supply ground; the common point of the first resistor and the second resistor is connected to the base of the first N-type transistor, and the collector of the first N-type transistor is connected to one end of the fifth resistor; one end of the third resistor is connected to a first preset power supply, the other end of the third resistor is connected to the other end of the fifth resistor, and the common point of the third resistor and the fifth resistor is connected to the base of the second P-type transistor; one end of the fourth resistor is connected to the first preset power supply, and the other end of the fourth resistor is connected to the emitter of the second P-type transistor. The collector of the second P-type transistor is connected to one end of the first capacitor, and the other end of the first capacitor is connected to the emitter of the first N-type transistor. The common point of the second P-type transistor and the first capacitor is connected to the base of the third N-type transistor and the base of the fourth P-type transistor. The collector of the third N-type transistor is connected to the first preset power supply, and the emitter of the third N-type transistor is connected to the emitter of the fourth P-type transistor. The base of the fourth P-type transistor is connected to one end of the sixth resistor, and the other end of the sixth resistor is connected to the emitter of the first N-type transistor. The common terminal of the emitter of the third N-type transistor and the emitter of the fourth P-type transistor is connected to one end of the seventh resistor; the other end of the seventh resistor is connected to the gate of the first field-effect transistor; the drain of the first field-effect transistor is connected to the anode of the first diode and the driving terminal of the single inductive load; the source of the first field-effect transistor is connected to the emitter of the first N-type transistor and then connected to the power supply ground through the overcurrent protection circuit; the cathode of the first diode is connected to the coil supply signal; one end of the second capacitor is connected to the drain of the first field-effect transistor; and the other end of the second capacitor is connected to the power supply ground.

[0010] Specifically, the overcurrent protection circuit includes: an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a fourteenth resistor, a fifth N-type transistor, and a sixth P-type transistor; wherein, the eighth and ninth resistors are connected in parallel, with one end connected to the source of the first field-effect transistor and the other end connected to power ground; one end of the tenth resistor is connected to the common terminal of the eighth resistor and the first field-effect transistor, and the other end is connected to one end of the eleventh resistor, the other end of which is connected to power ground; the tenth resistor and the... The common terminal of resistor eleven is connected to the base of the fifth N-type transistor, the emitter of the fifth N-type transistor is connected to the power supply ground, and the collector of the fifth N-type transistor is connected to one end of resistor twelfth; the other end of resistor twelfth is connected to one end of resistor thirteenth, and the other end of resistor thirteenth is connected to the second preset power supply; one end of resistor fourteenth is connected to the second preset power supply, and the other end of resistor fourteenth is connected to the emitter of transistor six P-type transistor; the common point of resistors twelfth and thirteenth is connected to the base of transistor six P-type transistor, and the collector of transistor six P-type transistor is connected to the drive current terminal.

[0011] Furthermore, the sampling circuit includes: a sixteenth resistor, a fifteenth resistor, and a third capacitor; wherein, one end of the sixteenth resistor is connected to a reference voltage, and the other end of the sixteenth resistor is connected to one end of the fifteenth resistor; the other end of the fifteenth resistor is connected to one end of the eighth resistor; one end of the third capacitor is grounded, and the other end of the third capacitor is connected to the common terminal of the sixteenth and fifteenth resistors.

[0012] Furthermore, the clamping circuit includes a second switching diode, the positive terminal of which is connected to the microcontroller input port, and the negative terminal of which is connected to the clamping power supply.

[0013] This utility model also proposes an engineering machine, including the drive circuit of the single inductive load described above.

[0014] The beneficial effects of this utility model are:

[0015] This invention achieves overcurrent protection for single inductive load drives at the hardware level by adding only a few components, improving the safety and reliability of single inductive load drives. Furthermore, when an overcurrent occurs, the sampled voltage value will suddenly jump, allowing the software to detect faults more accurately and promptly and make relevant diagnoses. Attached Figure Description

[0016] Figure 1 This is a block diagram of a drive circuit for a single inductive load according to an embodiment of the present invention.

[0017] Figure 2 This is a circuit topology diagram of a drive circuit for a single inductive load according to an embodiment of the present invention. Detailed Implementation

[0018] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0019] Figure 1 This is a block diagram of a drive circuit for a single inductive load according to an embodiment of the present invention, as shown below. Figure 1 As shown, the drive circuit includes: a switching circuit 1, an overcurrent protection circuit 2, a voltage sampling circuit 3, and a clamping circuit 4.

[0020] The switching circuit 1 includes a field-effect transistor (FET). One end of the switching circuit 1 is connected to the control signal terminal of the microcontroller, and the other end is connected to the driver terminal of the single inductive load. It is used to drive the FET to turn on / off according to the control signal of the microcontroller, thereby driving the single inductive load. One end of the overcurrent protection circuit 2 is connected to the drive current terminal of the single inductive load, and the other end is connected to the switching circuit 1. The overcurrent protection circuit 2 is used to turn on when the drive current exceeds the current threshold, so as to drive the FET of the switching circuit 1 to turn off. The voltage sampling circuit 3 is connected to the drive current terminal and the FET. The voltage sampling circuit 3 is used to collect the drive voltage of the single inductive load and drive the FET of the switching circuit 1 to turn off when the drive voltage exceeds the voltage threshold. The clamping circuit 4 is connected to the input port of the microcontroller. The clamping circuit 4 is used to clamp the voltage input to the microcontroller within a first set voltage (e.g., 5V).

[0021] Specifically, a single inductive load can be a relay, a solenoid valve, etc. For example... Figure 1As shown, the switching circuit 1 controls the conduction and cutoff of the field-effect transistor (FET) according to the high and low changes of the control signal issued by the microcontroller. When the current in the circuit is too large, the overcurrent protection circuit 2 is activated, providing a high voltage to the source of the FET. At this time, the drain and gate voltages remain unchanged. When the voltage difference between the gate and source is less than the FET's turn-on voltage, the FET is cut off, thus achieving overcurrent protection for the single inductive load. The voltage sampling circuit 3 collects the drive voltage of the single inductive load based on the current at the drive current terminal. When an overcurrent occurs, the sampled voltage value of the voltage sampling circuit 3 will suddenly jump, causing the drive voltage to exceed the preset voltage threshold. The microcontroller can identify the overcurrent by monitoring the voltage of the voltage sampling circuit 3. The clamping circuit 4 is connected to the microcontroller's input port, which is the power input port, and can clamp the voltage input to the microcontroller within a first set voltage. Therefore, this utility model can achieve overcurrent protection for single inductive load drive at the hardware level by adding only a small number of components, which improves the safety and reliability of single inductive load drive. Moreover, when an overcurrent occurs, the sampled voltage value will suddenly jump, which allows the software to detect the fault more accurately and timely and make relevant diagnoses, thus achieving both hardware and software protection for single inductive load drive.

[0022] In one specific embodiment of this utility model, such as Figure 2 As shown, the switching circuit 1 may specifically include: a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a seventh resistor R7, a first capacitor C1, a second capacitor C2, a first diode D1, a first N-type transistor Q1, a second P-type transistor Q2, a third N-type transistor Q3, a fourth P-type transistor Q4, and a first field-effect transistor J1, wherein the first field-effect transistor J1 is an N-channel enhancement-mode field-effect transistor;

[0023] In this circuit, one end of the first resistor R1 is connected to the control signal terminal of the microcontroller, and the other end of the first resistor R1 is connected to one end of the second resistor R2. The other end of the second resistor R2 is connected to the power supply ground. The common point of the first resistor R1 and the second resistor R2 is connected to the base of the first N-type transistor Q1, and the collector of the first N-type transistor Q1 is connected to one end of the fifth resistor R5. One end of the third resistor R3 is connected to the first preset power supply VCC1 (+15V), and the other end of the third resistor R3 is connected to the fifth resistor. The other end of R5, the common point of the third resistor R3 and the fifth resistor R5, is connected to the base of the second P-type transistor Q2; one end of the fourth resistor R4 is connected to the first preset power supply VCC1, and the other end of the fourth resistor R4 is connected to the emitter of the second P-type transistor Q2; the collector of the second P-type transistor Q2 is connected to one end of the first capacitor C1, and the other end of the first capacitor C1 is connected to the emitter of the first N-type transistor Q1; the common point of the second P-type transistor Q2 and the first capacitor C1 is connected to the third N-type transistor Q1. The base of transistor Q3 is connected to the base of transistor Q4 (P-type). The collector of transistor Q3 is connected to the first preset power supply VCC1. The emitter of transistor Q3 is connected to the emitter of transistor Q4 (P-type). The base of transistor Q4 is connected to one end of resistor R6. The other end of resistor R6 is connected to the emitter of transistor Q1 (N-type). The common terminal of the emitters of transistors Q3 and Q4 is connected to one end of resistor R7. The other end is connected to the gate G of the first field-effect transistor J1. The drain D of the first field-effect transistor J1 is connected to the positive terminal of the first diode D1 and the driver terminal of the single inductive load. The source S of the first field-effect transistor J1 is connected to the emitter of the first N-type transistor Q1 and then connected to the power supply ground through the overcurrent protection circuit 2. The negative terminal of the first diode D1 is connected to the coil supply signal COIL-SUPPLY. One end of the second capacitor C2 is connected to the drain D of the first field-effect transistor J1, and the other end of the second capacitor C2 is connected to the power supply ground. The coil supply signal is a valve-controlled power supply signal, which is generally DC and has a voltage of 24V.

[0024] In one specific embodiment of this utility model, such as Figure 2 As shown, the overcurrent protection circuit 2 may specifically include: the eighth resistor R8, the ninth resistor R9, the tenth resistor R10, the eleventh resistor R11, the twelfth resistor R12, the thirteenth resistor R13, the fourteenth resistor R14, the fifth N-type transistor Q5, and the sixth P-type transistor Q6.

[0025] Among them, the eighth resistor R8 and the ninth resistor R9 are connected in parallel, with one end connected to the source of the first field-effect transistor J1 and the other end connected to the power supply ground; one end of the tenth resistor R10 is connected to the common terminal of the eighth resistor R8 and the first field-effect transistor J1, and the other end is connected to one end of the eleventh resistor R11, with the other end of the eleventh resistor R11 connected to the power supply ground; the common terminal of the tenth resistor R10 and the eleventh resistor R11 is connected to the base of the fifth N-type transistor Q5, the emitter of the fifth N-type transistor Q5 is connected to the power supply ground, and the collector of the fifth N-type transistor Q5... One end of the twelfth resistor R12 is connected to the electrode; the other end of the twelfth resistor R12 is connected to one end of the thirteenth resistor R13, and the other end of the thirteenth resistor R13 is connected to the second preset power supply VCC3 (+5V); one end of the fourteenth resistor R14 is connected to the second preset power supply VCC2, and the other end of the fourteenth resistor R14 is connected to the emitter of the sixth P-type transistor Q6; the common point of the twelfth resistor R12 and the thirteenth resistor R13 is connected to the base of the sixth P-type transistor Q6; and the collector of the sixth P-type transistor Q6 is connected to the drive current terminal.

[0026] In one specific embodiment of this utility model, such as Figure 2 As shown, the sampling circuit 3 includes: a sixteenth resistor R16, a fifteenth resistor R15, and a third capacitor C3; wherein, one end of the sixteenth resistor R16 is connected to the reference voltage Reference, and the other end of the sixteenth resistor R16 is connected to one end of the fifteenth resistor R15; the other end of the fifteenth resistor R15 is connected to one end of the eighth resistor R8; one end of the third capacitor C3 is grounded, and the other end of the third capacitor C3 is connected to the common terminal of the sixteenth resistor R16 and the fifteenth resistor R15.

[0027] In one specific embodiment of this utility model, such as Figure 2 As shown, the clamping circuit 4 includes: a second switching diode D2, the positive terminal of the second switching diode D2 is connected to the microcontroller input port, and the negative terminal of the second switching diode is connected to the clamping power supply Clamp.

[0028] Figure 2 In this context, the working principle of the drive circuit for a single inductive load is as follows:

[0029] When the control signal sent by the microcontroller is 0V low level:

[0030] The base of the first transistor Q1 is at a low level, so the first transistor Q1 is cut off; the voltage difference between the emitter and base voltages of the second transistor Q2 is less than the turn-on voltage, so the second transistor Q2 is cut off; the base of the third transistor Q3 is at a low level, so the third transistor Q3 is cut off; the voltage difference between the base and emitter voltages of the fourth transistor Q4 is less than the turn-on voltage, so the fourth transistor Q4 is cut off; at this time, the gate of the first field-effect transistor J1 is at a low level, so the first field-effect transistor J1 is cut off.

[0031] The base of transistor Q5 is at a low level, and the collector is at a high level, so transistor Q5 is cut off; the base and emitter of transistor Q6 are at high levels, so transistor Q6 is cut off.

[0032] The sixteenth resistor R16 and the fifteenth resistor R15 divide the voltage. The clamping circuit 4 clamps the voltage input to the microcontroller to within 5V. The microcontroller monitors the voltage across the fifteenth resistor R15 after filtering.

[0033] When the control signal sent by the CPU is 3.3V high level:

[0034] The base of the first transistor Q1 is at a high level, and the generator is at a low level, so the first transistor Q1 is turned on. The emitter voltage of the second transistor Q2 is greater than the base voltage, so the second transistor Q2 is turned on. The base of the third transistor Q3 is at a high level, and the generator is at a low level, so the third transistor Q3 is turned on. The emitter voltage of the fourth transistor Q4 is greater than the base voltage, so the fourth transistor Q4 is turned on. At this time, the gate of the field-effect transistor J1 is at a high level, so the field-effect transistor is turned on, realizing the driving of a single inductive load.

[0035] When the first field-effect transistor J1 is turned on, and the coil drive current is too large, the base voltage of the fifth transistor Q5 rises. When the voltage difference between the base voltage and the emitter voltage is greater than the turn-on voltage, the fifth transistor Q5 turns on. The emitter voltage of the sixth transistor Q6 is greater than the base voltage, so the sixth transistor Q6 turns on, providing a high voltage to the source of the first field-effect transistor J1. At this time, the voltage difference between the gate and source of the field-effect transistor J1 is less than the turn-on voltage of the field-effect transistor, so the field-effect transistor J1 is turned off, and the single inductive load stops driving, realizing hardware overcurrent protection.

[0036] c) The voltage divider between the sixteenth resistor R16 and the fifteenth resistor R15 clamps the voltage input to the microcontroller to within 5V. The microcontroller monitors the voltage of the filtered fifteenth resistor R15 and the source voltage of the first field-effect transistor J1. When the voltage exceeds the reference voltage, the microcontroller controls the output signal to turn off the first field-effect switch circuit J1 to achieve software-level overcurrent protection.

[0037] In summary, the single inductive load driving circuit of this utility model can achieve overcurrent protection for single inductive load driving at the hardware level by adding only a small number of components, thereby improving the safety and reliability of single inductive load driving. Furthermore, when an overcurrent occurs, the sampled voltage value will suddenly jump, allowing the software to detect the fault more accurately and promptly and make relevant diagnoses.

[0038] In addition, this utility model also proposes an engineering machine, including the drive circuit of the single inductive load described above.

[0039] According to the engineering machinery of this utility model, through the above-mentioned single inductive load drive circuit, overcurrent protection of single inductive load drive can be achieved at the hardware level by only adding a small number of components, which improves the safety and reliability of single inductive load drive. Moreover, when overcurrent occurs, the sampled voltage value will suddenly jump, which allows the software to detect the fault more accurately and timely and make relevant diagnoses.

[0040] In the description of this utility model, it should be understood that the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this utility model, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0041] In this utility model, unless otherwise explicitly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0042] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0043] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A drive circuit for a single inductive load, characterized in that, include: A switching circuit, including a field-effect transistor, is provided. One end of the switching circuit is connected to the control signal terminal of a microcontroller, and the other end is connected to the driving terminal of a single inductive load. The switching circuit is used to drive the field-effect transistor to turn on / off according to the control signal of the microcontroller, thereby driving the single inductive load. An overcurrent protection circuit is provided, one end of which is connected to the drive current terminal of a single inductive load, and the other end of which is connected to the switching circuit. The overcurrent protection circuit is used to turn on when the drive current exceeds the current threshold, so as to drive the field-effect transistor of the switching circuit to turn off. A voltage sampling circuit is connected to the drive current terminal and the field-effect transistor. The voltage sampling circuit is used to collect the drive voltage of the single inductive load and drive the field-effect transistor of the switching circuit to turn off when the drive voltage exceeds the voltage threshold. A clamping circuit is connected to the microcontroller input port and is used to clamp the voltage input to the microcontroller within a first set voltage.

2. The driving circuit for a single inductive load according to claim 1, characterized in that, The switching circuit specifically includes: The first resistor, the second resistor, the third resistor, the fourth resistor, the fifth resistor, the sixth resistor, the seventh resistor, the first capacitor, the second capacitor, the first diode, the first N-type transistor, the second P-type transistor, the third N-type transistor, the fourth P-type transistor, and the first field-effect transistor, wherein the first field-effect transistor is an N-channel enhancement-mode field-effect transistor. In this circuit, one end of the first resistor is connected to the microcontroller's control signal terminal, and the other end of the first resistor is connected to one end of the second resistor, the other end of the second resistor being connected to the power supply ground. The common point of the first and second resistors is connected to the base of the first N-type transistor, and the collector of the first N-type transistor is connected to one end of the fifth resistor. One end of the third resistor is connected to the first preset power supply, and the other end of the third resistor is connected to the other end of the fifth resistor. The common point of the third and fifth resistors is connected to the base of the second P-type transistor. One end of the fourth resistor is connected to the first preset power supply, and the other end of the fourth resistor is connected to the emitter of the second P-type transistor. The collector of the second P-type transistor is connected to one end of the first capacitor, and the other end of the first capacitor is connected to the emitter of the first N-type transistor. The common point of the second P-type transistor and the first capacitor is connected to the base of the third N-type transistor. The base of the transistor is connected to the base of the fourth P-type transistor, and the collector of the third N-type transistor is connected to the first preset power supply. The emitter of the third N-type transistor is connected to the emitter of the fourth P-type transistor. The base of the fourth P-type transistor is connected to one end of the sixth resistor, and the other end of the sixth resistor is connected to the emitter of the first N-type transistor. The common terminal of the emitter of the third N-type transistor and the emitter of the fourth P-type transistor is connected to one end of the seventh resistor. The other end of the seventh resistor is connected to the gate of the first field-effect transistor. The drain of the first field-effect transistor is connected to the anode of the first diode and the driving terminal of the single inductive load. The source of the first field-effect transistor is connected to the emitter of the first N-type transistor and then connected to the power supply ground through the overcurrent protection circuit. The cathode of the first diode is connected to the coil supply signal. One end of the second capacitor is connected to the drain of the first field-effect transistor, and the other end of the second capacitor is connected to the power supply ground.

3. The driving circuit for a single inductive load according to claim 2, characterized in that, The overcurrent protection circuit includes: an eighth resistor, a ninth resistor, a tenth resistor, an eleventh resistor, a twelfth resistor, a thirteenth resistor, a fourteenth resistor, a fifth N-type transistor, and a sixth P-type transistor. Among them, the eighth and ninth resistors are connected in parallel, with one end connected to the source of the first field-effect transistor and the other end connected to the power supply ground; one end of the tenth resistor is connected to the common terminal of the eighth resistor and the first field-effect transistor, and the other end is connected to one end of the eleventh resistor, the other end of the eleventh resistor is connected to the power supply ground; the common terminal of the tenth and eleventh resistors is connected to the base of the fifth N-type transistor, the emitter of the fifth N-type transistor is connected to the power supply ground, and the collector of the fifth N-type transistor is connected to one end of the twelfth resistor; the other end of the twelfth resistor is connected to one end of the thirteenth resistor, the other end of the thirteenth resistor is connected to the second preset power supply; one end of the fourteenth resistor is connected to the second preset power supply, the other end of the fourteenth resistor is connected to the emitter of the sixth P-type transistor, the common point of the twelfth and thirteenth resistors is connected to the base of the sixth P-type transistor, and the collector of the sixth P-type transistor is connected to the drive current terminal.

4. The driving circuit for a single inductive load according to claim 3, characterized in that, The sampling circuit includes: a sixteenth resistor, a fifteenth resistor, and a third capacitor; Among them, one end of the sixteenth resistor is connected to the reference voltage, and the other end of the sixteenth resistor is connected to one end of the fifteenth resistor; the other end of the fifteenth resistor is connected to one end of the eighth resistor; one end of the third capacitor is grounded, and the other end of the third capacitor is connected to the common terminal of the sixteenth and fifteenth resistors.

5. The driving circuit for a single inductive load according to claim 4, characterized in that, The clamping circuit includes: The positive terminal of the second switching diode is connected to the microcontroller input port, and the negative terminal is connected to the clamping power supply.

6. An engineering machinery, characterized in that, The driving circuit includes the single inductive load according to any one of claims 1-5.

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