Seat fan driving circuit, seat ventilation system and vehicle

Abstract

The utility model relates to the technical field of electronics, in particular to a seat fan driving circuit, a seat ventilation system and a vehicle. The seat fan driving circuit comprises a signal processing circuit used for accessing a driving signal; comprising a first enabling circuit and a second enabling circuit, one end of the first enabling circuit and one end of the second enabling circuit are both electrically connected with the signal processing circuit, the other end of the first enabling circuit and the other end of the second enabling circuit are both electrically connected with a load power supply node, and when the load is in high-side driving, the first enabling circuit and the second enabling circuit are configured to be in high-side driving. When the load is in low-side driving, a first enable signal is output through the first enable circuit, and when the load is in low-side driving, a second enable signal is output through the second enable circuit. Therefore, through the seat fan driving circuit, high-low side compatibility design can be carried out on load driving, the problems that in the prior art, different seat controllers need to be matched for a high-side or low-side seat fan, and compatibility cannot be achieved are solved, and the complexity and cost of circuit design are reduced.

Description

Technical Field

[0001] The utility model relates to the field of electronic technology, and in particular to a seat fan driving circuit, a seat ventilation system and a vehicle. Background Art

[0002] With the demand of the vehicle market, many vehicles have been equipped with seat ventilation function, which requires driving the ventilation fan. Generally speaking, the drive circuit mainly includes two parts: power drive and PWM (Pulse Width Modulation) speed control drive. The ventilation fan PWM speed control drive can be divided into high-side drive and low-side drive.

[0003] In the related technologies, most of the designs of ventilation fan driving circuits are designed with discrete components, and targeted circuit designs are performed according to the PWM speed regulation characteristics of the ventilation fan. For example, the vehicle seat controller drives the low-side ventilation fan circuit using NPN (Negative Positive Negative, negative-positive-negative) transistors to build the circuit. The main control chip drives the B-level of the NPN tube through PWM to output. There is a power pull-up resistor at the fan end, and there is no need to add a pull-up resistor to the C-level NPN tube.

[0004] However, the related technology can only adapt different seat control circuits for high-side or low-side seat fans, without considering the compatibility design for the high-side and low-side drive modes of the load, which urgently needs to be improved. Utility Model Content

[0005] The utility model provides a seat fan driving circuit, a seat ventilation system and a vehicle, so as to solve the problem that the prior art needs to adapt different seat controllers for high-side or low-side seat fans and cannot achieve compatibility, thereby reducing the complexity and cost of circuit design.

[0006] To achieve the above-mentioned object, the first embodiment of the utility model provides a seat fan driving circuit, comprising:

[0007] A signal processing circuit, used for receiving a driving signal;

[0008] A driving circuit, the driving circuit comprising a first enabling circuit and a second enabling circuit, one end of the first enabling circuit and one end of the second enabling circuit are both electrically connected to the signal processing circuit, the other end of the first enabling circuit and the other end of the second enabling circuit are both electrically connected to a load power supply node, and are configured to output a first enabling signal through the first enabling circuit when the load is a high-side drive, and to output a second enabling signal through the second enabling signal when the load is a low-side drive.

[0009] Optionally, the first enabling circuit includes:

[0010] a first switch, wherein a first end of the first switch is electrically connected to a control end of the first switch and a first power access node, respectively, and a second end of the first switch is electrically connected to the first power access node and the signal processing circuit, respectively;

[0011] a second switch, wherein a first end of the second switch is electrically connected to a control end of the first switch, the control end of the second switch is electrically connected to a second end of the first switch and the signal processing circuit respectively, and a second end of the second switch is electrically connected to the load power supply node;

[0012] a first resistor, one end of the first resistor being electrically connected to the first end of the first switch and the first power access node respectively, and the other end of the first resistor being electrically connected to the second end of the first switch;

[0013] a second resistor, one end of the second resistor being electrically connected to the second end of the first switch, and the other end of the second resistor being electrically connected to the signal processing circuit;

[0014] a third resistor, one end of the third resistor being electrically connected to the first end of the first switch, and the other end of the third resistor being electrically connected to the control end of the first switch.

[0015] Optionally, the second enabling circuit includes:

[0016] A fourth resistor, one end of the fourth resistor is electrically connected to the signal processing circuit, and the other end of the fourth resistor is electrically connected to the load power supply node.

[0017] Optionally, the signal processing circuit includes:

[0018] A signal input terminal, used for receiving the driving signal;

[0019] a third switch, wherein a control end of the third switch is electrically connected to the signal input end, a first end of the third switch is electrically connected to a ground node, and a second end of the third switch is electrically connected to one end of the drive circuit;

[0020] a fifth resistor, one end of the fifth resistor being electrically connected to the signal input end, and the other end of the fifth resistor being electrically connected to the control end of the third switch;

[0021] A sixth resistor, one end of the sixth resistor is electrically connected to the other end of the fifth resistor and the control end of the third switch respectively, and the other end of the sixth resistor is electrically connected to the first end of the third switch and the ground node respectively.

[0022] Optionally, the seat fan driving circuit further includes:

[0023] A first protection circuit, wherein the first protection circuit comprises a seventh resistor and a first capacitor, wherein:

[0024] One end of the seventh resistor is electrically connected to the other end of the driving circuit, and the other end of the seventh resistor is electrically connected to the load power supply node;

[0025] One end of the first capacitor is electrically connected to the other end of the seventh resistor and the load power supply node respectively, and the other end of the first capacitor is electrically connected to the ground node.

[0026] Optionally, the seat fan driving circuit further includes:

[0027] A voltage detection output terminal for detecting the voltage of the load power supply node;

[0028] The second protection circuit, the second protection resistor includes an eighth resistor, a ninth resistor, a tenth resistor and a second capacitor, wherein:

[0029] One end of the eighth resistor is electrically connected to the other end of the driving circuit and one end of the seventh resistor;

[0030] One end of the ninth resistor is electrically connected to the other end of the eighth resistor, and the other end of the ninth resistor is electrically connected to the ground node;

[0031] One end of the tenth resistor is electrically connected to the connection node between the eighth resistor and the ninth resistor, and the other end of the tenth resistor is electrically connected to the voltage detection output terminal;

[0032] A second capacitor, one end of the second capacitor is electrically connected to the other end of the tenth resistor and the voltage detection output end respectively, and the other end of the second capacitor is electrically connected to the ground node.

[0033] Optionally, the second protection circuit further includes:

[0034] an eleventh resistor, one end of the eleventh resistor being electrically connected to the second power supply access node;

[0035] A fourth switch, wherein a first end of the fourth switch is electrically connected to the other end of the eleventh resistor and the voltage detection node respectively, a control end of the fourth switch is electrically connected to the other end of the tenth resistor, and a second end of the fourth switch is electrically connected to the ground node.

[0036] Optionally, the seat fan driving circuit further includes:

[0037] An alarm circuit is electrically connected to the voltage detection output terminal, and the alarm circuit performs an acoustic alarm and / or an optical alarm when the voltage at the voltage detection output terminal is greater than a preset threshold.

[0038] According to the seat fan driving circuit proposed by the utility model, the driving signal is connected through the signal processing circuit; through the driving circuit, including the first enabling circuit and the second enabling circuit, one end of the first enabling circuit and one end of the second enabling circuit are both electrically connected to the signal processing circuit, the other end of the first enabling circuit and the other end of the second enabling circuit are both electrically connected to the load power supply node, and are configured to output the first enabling signal through the first enabling circuit when the load is high-side driven, and output the second enabling signal through the second enabling signal when the load is low-side driven. Therefore, the seat fan driving circuit can be used to design high- and low-side compatibility for the load drive, solving the problem that the prior art needs to adapt different seat controllers for high-side or low-side seat fans and cannot achieve compatibility, thereby reducing the complexity and cost of circuit design.

[0039] In order to achieve the above-mentioned object, a second embodiment of the present invention provides a seat ventilation system, which includes the above-mentioned seat fan driving circuit.

[0040] In order to achieve the above-mentioned object, a third aspect of the present invention provides a vehicle, which includes the above-mentioned seat ventilation system.

[0041] Additional aspects and advantages of the present invention will be given in part in the following description and in part will become apparent from the following description or will be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0043] Figure 1 The present invention is a schematic diagram of the structure of a seat fan driving circuit provided according to an embodiment of the present invention. DETAILED DESCRIPTION

[0044] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0045] The seat fan driving circuit, the seat ventilation system and the vehicle according to the embodiments of the present invention will be described below with reference to the accompanying drawings. First, the seat fan driving circuit according to the embodiments of the present invention will be described with reference to the accompanying drawings.

[0046] Figure 1 It is a structural schematic diagram of a seat fan driving circuit of the utility model.

[0047] like Figure 1 As shown, the seat fan driving circuit 10 includes: a signal processing circuit 100 and a driving circuit 200 .

[0048] Among them, the signal processing circuit 100 is used to access the driving signal; the driving circuit 200 includes a first enabling circuit 201 and a second enabling circuit 202, one end of the first enabling circuit 201 and one end of the second enabling circuit 202 are both electrically connected to the signal processing circuit 100, the other end of the first enabling circuit 201 and the other end of the second enabling circuit 202 are both electrically connected to the load power supply node, and are configured to output a first enabling signal through the first enabling circuit 201 when the load is a high-side drive, and output a second enabling signal through the second enabling circuit 202 when the load is a low-side drive.

[0049] Among them, the load power supply node is the seat fan interface.

[0050] Specifically, the signal processing circuit 100 is connected to the drive signal to drive the load. When the load is a high-side drive, the first enable circuit 201 will output a first enable signal, which can be used to start or control actions related to the high-side drive. Similarly, when the load is a low-side drive, the second enable circuit 202 will output a second enable signal for starting or controlling actions related to the low-side drive. By making the high-side and low-side drive of the load compatible, it is helpful to provide more accurate and reliable control in various situations, while avoiding the cumbersome process of designing circuits for high-side and low-side drives separately in traditional designs, reducing the complexity and cost of circuit design.

[0051] Optionally, the signal processing circuit 100 includes: a signal input terminal 101, a third switch Q3, a fifth resistor R5 and a sixth resistor R6, wherein the signal input terminal 101 is used to access a driving signal; a third switch, a control terminal of the third switch Q3 is electrically connected to the signal input terminal 101, a first terminal of the third switch Q3 is electrically connected to a ground node, and a second terminal of the third switch Q3 is electrically connected to one terminal of the driving circuit 200; one terminal of the fifth resistor R5 is electrically connected to the signal input terminal 101, and the other terminal of the fifth resistor R5 is electrically connected to the control terminal of the third switch Q3; one terminal of the sixth resistor R6 is electrically connected to the other terminal of the fifth resistor R5 and the control terminal of the third switch Q3, respectively, and the other terminal of the sixth resistor R6 is electrically connected to the first terminal of the third switch Q3 and the ground node, respectively.

[0052] It should be noted that the signal input terminal 101 is the MCU (Micro Controller Unit) PWM signal sending pin, which is a GPIO (General Purpose Input Output) port with a timer function, and can output a PWM waveform with a specific frequency and duty cycle; the third switch Q3 is a transistor, the control end of the third switch Q3 is the base B of Q3, the first end of the third switch Q3 is the emitter E of Q3, and the second end of the third switch Q3 is the collector C of Q3.

[0053] Specifically, after receiving the input signal, the signal processing circuit 100 can perform necessary processing on the input signal according to actual needs, such as amplification, filtering or modulation. After the processing is completed, a PWM waveform with a specific frequency and duty cycle, i.e., a drive signal, can be output through the signal input terminal 101. The drive signal is connected to the drive circuit 200, and the drive circuit 200 can convert the drive signal into a current or voltage that can drive the load, and load it to the target load, so that the load works as expected.

[0054] To facilitate further understanding, the working principles of high-side drive and low-side drive are explained in detail below.

[0055] Optionally, the first enabling circuit 201 includes: a first switch Q1, a second switch Q2, a first resistor R1, a second resistor R2 and a third resistor R3, wherein a first end of the first switch Q1 is electrically connected to a control end of the first switch Q1 and a first power access node, respectively, and a second end of the first switch Q1 is electrically connected to the first power access node and the signal processing circuit 100, respectively; a first end of the second switch Q2 is electrically connected to a control end of the first switch Q1, a control end of the second switch Q2 is electrically connected to a second end of the first switch Q1 and the signal processing circuit 100, and a second end of the second switch Q2 is electrically connected to a load power supply node; a first resistor, one end of the first resistor R1 is electrically connected to a first end of the first switch Q1 and the first power access node, respectively, and the other end of the first resistor R1 is electrically connected to the second end of the first switch Q1; one end of the second resistor R2 is electrically connected to the second end of the first switch Q1, and the other end of the second resistor R2 is electrically connected to the signal processing circuit 100; one end of the third resistor R3 is electrically connected to a first end of the first switch Q1, and the other end of the third resistor R3 is electrically connected to the control end of the first switch Q1.

[0056] It should be noted that the first switch Q1 and the second switch Q2 are both triodes, the first end of the first switch Q1 is the emitter E of Q1, the control end of the first switch Q1 is the base B of Q1, the second end of the first switch Q1 is the collector C of Q1, the first end of the second switch Q2 is the emitter E of Q2, the control end of the second switch Q2 is the base B of Q2, and the second end of the second switch Q2 is the collector C of Q2.

[0057] Specifically, when the load is a high-side drive, the signal input terminal 101 outputs a PWM waveform (i.e., a drive signal) of a specific frequency and duty cycle to drive the third switch Q3 to turn on. After the third switch Q3 is turned on, the second switch Q2 is driven to turn on through the first resistor R1 and the second resistor R2, and the signal is output to the load power supply node through the second switch Q2, thereby completing the high-side PWM drive speed regulation function of the seat fan.

[0058] Optionally, the second enabling circuit 202 includes: a fourth resistor R4, one end of the fourth resistor R4 is electrically connected to the signal processing circuit 100, and the other end of the fourth resistor R4 is electrically connected to the load power supply node.

[0059] Specifically, when the load is a low-side drive, the signal input terminal 101 outputs a PWM waveform (i.e., a drive signal) of a specific frequency and duty cycle, driving the third switch Q3 to turn on. After the third switch Q3 is turned on, it is output to the load power supply node through the fourth resistor R4, thereby completing the low-side PWM drive speed regulation function of the seat fan.

[0060] It should be noted that when the load is a low-side drive, the first enabling circuit 201 does not work; when the load is a high-side drive, the second enabling circuit 202 does not work.

[0061] Optionally, the seat fan driving circuit 10 also includes: a first protection circuit 300, the first protection circuit 300 includes a seventh resistor R7 and a first capacitor C1, wherein one end of the seventh resistor R7 is electrically connected to the other end of the driving circuit 200, and the other end of the seventh resistor R7 is electrically connected to the load power supply node; one end of the first capacitor C1 is electrically connected to the other end of the seventh resistor R7 and the load power supply node, respectively, and the other end of the first capacitor C1 is electrically connected to the ground node.

[0062] It can be understood that in order to protect the load so that it can operate safely under abnormal circumstances and prevent the load elements from being damaged, the seat fan drive circuit 10 is also provided with a protection circuit, wherein the first protection circuit 300 includes a current limiting resistor (i.e., the seventh resistor R7) and a filter capacitor (i.e., the first capacitor C1). When the load elements in the circuit cannot withstand excessive current, the current can be limited by the first protection circuit 300, thereby protecting the load elements.

[0063] Optionally, the seat fan drive circuit 10 also includes: a voltage detection output terminal 400 and a second protection circuit 500, the voltage detection output terminal 400 is used to detect the load power supply node voltage, the second protection circuit 400 includes an eighth resistor R8, a ninth resistor R9, a tenth resistor R10 and a second capacitor C2, wherein one end of the eighth resistor R8 is electrically connected to the other end of the drive circuit 200 and one end of the seventh resistor R7; one end of the ninth resistor R9 is electrically connected to the other end of the eighth resistor R8, and the other end of the ninth resistor R9 is electrically connected to the ground node; one end of the tenth resistor R10 is electrically connected to the connection node between the eighth resistor R8 and the ninth resistor R9, and the other end of the tenth resistor R10 is electrically connected to the voltage detection output terminal 400; one end of the second capacitor C2 is electrically connected to the other end of the tenth resistor R10 and the voltage detection output terminal 400, respectively, and the other end of the second capacitor C2 is electrically connected to the ground node.

[0064] It should be noted that the voltage detection output terminal 400 is an MCU sampling receiving pin and is a pin with an ADC (Analog-to-Digital Converter) function. By reading the input voltage value of the pin, the circuit voltage can be fed back.

[0065] Optionally, the second protection circuit 500 further includes: an eleventh resistor R11 and a fourth switch Q4, wherein one end of the eleventh resistor R11 is electrically connected to the second power supply access node; the first end of the fourth switch Q4 is electrically connected to the other end of the eleventh resistor R11 and the voltage detection node respectively, the control end of the fourth switch Q4 is electrically connected to the other end of the tenth resistor R10, and the second end of the fourth switch Q4 is electrically connected to the ground node.

[0066] The fourth switch Q4 is a triode, the first end of the fourth switch Q4 is the collector C of Q4 , the control end of the fourth switch Q4 is the base B, and the second end of the fourth switch Q4 is the emitter E.

[0067] Specifically, in the second protection circuit 500, after the eighth resistor R8 and the ninth resistor R9 are divided by voltage, the fourth switch Q4 is driven to be turned on through the tenth resistor R10, thereby realizing the feedback of the circuit output voltage by the voltage detection output terminal 400. When it is found through the voltage detection output terminal 400 that the output voltage is too large, timely measures can be taken to prevent the excessively high voltage from causing damage to the circuit or related equipment (load).

[0068] It should be noted that the first power supply and the second power supply are both pull-up power supplies, which can provide a high-level pulse in a short time and pull the logic level from a low-level state to a high-level state when starting or resetting. The first to fourth switches Q1 to Q4 are all triodes, and their types include but are not limited to NPN and PNP (Positive Negative Positive, positive-negative-positive) types, which are not specifically limited here. The first resistor R1, the second resistor R2, the fifth resistor R5, the sixth resistor R6, and the eighth to eleventh resistors R8 to R11 are all voltage-dividing resistors, which can be used for (1) reducing voltage, that is, reducing the voltage of the device powered by the power supply to a suitable range, (2) stabilizing voltage, that is, the voltage-dividing resistor can convert a voltage input with large fluctuations into an output voltage with small fluctuations, and (3) protecting the circuit, that is, when the high-voltage input pin is connected to a low-voltage electronic component, the voltage-dividing resistor can limit the input voltage to avoid damage to the electronic component; the third resistor R3, the fourth resistor R4 and the seventh resistor R7 are all current-limiting resistors, which can protect other electronic components in the circuit by limiting the current size, wherein the materials, structures, physical properties and implementation forms of the voltage-dividing resistors and the current-limiting resistors are not specifically limited. The first capacitor C1 and the second capacitor C2 are both filter capacitors, which can filter out the fluctuations and noise generated by the power supply, so that the voltage output of the power supply is more stable, wherein the materials, structures, physical properties and implementation forms of the capacitors are not specifically limited.

[0069] Optionally, the seat fan drive circuit 10 further includes: an alarm circuit 600, which is electrically connected to the voltage detection output terminal 400, and the alarm circuit 600 performs an acoustic alarm and / or an optical alarm when the voltage at the voltage detection output terminal 400 is greater than a preset threshold.

[0070] The preset threshold may be pre-set by a person skilled in the art, or may be obtained through a limited number of experiments, or may be obtained through a limited number of computer simulations, and is not specifically limited here.

[0071] Specifically, when the voltage at the voltage detection output terminal 400 exceeds a preset threshold, the alarm circuit 600 can receive a signal exceeding the threshold and trigger an alarm mechanism to perform an acoustic and / or optical alarm. Among them, the acoustic alarm can emit an alarm tone through a buzzer or a speaker, and the optical alarm can emit light through an LED (Light Emitting Diode) lamp or other light-emitting elements, so that measures can be taken in time to deal with abnormal situations. By electrically connecting the alarm circuit 600 to the voltage detection output terminal 400, and combining the acoustic alarm and the optical alarm, an efficient and reliable voltage monitoring module can be constructed to ensure circuit safety.

[0072] In summary, the seat fan driving circuit proposed in the utility model is connected to the driving signal through the signal processing circuit; through the driving circuit, it includes a first enabling circuit and a second enabling circuit, one end of the first enabling circuit and one end of the second enabling circuit are both electrically connected to the signal processing circuit, the other end of the first enabling circuit and the other end of the second enabling circuit are both electrically connected to the load power supply node, and is configured to output a first enabling signal through the first enabling circuit when the load is a high-side drive, and output a second enabling signal through the second enabling signal when the load is a low-side drive. Therefore, the seat fan driving circuit can be used to design high- and low-side compatibility for the load drive, solving the problem that the prior art needs to adapt different seat controllers for high-side or low-side seat fans and cannot achieve compatibility, thereby reducing the complexity and cost of circuit design.

[0073] Secondly, the utility model provides a seat ventilation system, the system comprising Figure 1 A seat fan driving circuit according to an embodiment.

[0074] In summary, the seat ventilation system proposed in the present invention solves the problem that the prior art needs to adapt different seat controllers for high-side or low-side seat fans and cannot achieve compatibility through the seat fan driving circuit, thereby reducing the complexity and cost of circuit design.

[0075] The utility model also provides a vehicle, which comprises the seat ventilation system mentioned above.

[0076] In summary, the vehicle proposed in the present invention solves the problem that the prior art needs to adapt different seat controllers for high-side or low-side seat fans and cannot achieve compatibility through the seat ventilation system, thereby reducing the complexity and cost of circuit design.

[0077] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present utility model, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0078] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0079] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limitations of the present invention. Ordinary technicians in the field can change, modify, replace and modify the above embodiments within the scope of the present invention.

Claims

1. A seat fan driving circuit, characterized in that: include: A signal processing circuit, used for receiving a driving signal; A driving circuit, the driving circuit comprising a first enabling circuit and a second enabling circuit, one end of the first enabling circuit and one end of the second enabling circuit are both electrically connected to the signal processing circuit, the other end of the first enabling circuit and the other end of the second enabling circuit are both electrically connected to a load power supply node, and are configured to output a first enabling signal through the first enabling circuit when the load is a high-side drive, and to output a second enabling signal through the second enabling circuit when the load is a low-side drive.

2. The seat fan driving circuit according to claim 1, characterized in that: The first enabling circuit comprises: a first switch, wherein a first end of the first switch is electrically connected to a control end of the first switch and a first power access node, respectively, and a second end of the first switch is electrically connected to the first power access node and the signal processing circuit, respectively; a second switch, wherein a first end of the second switch is electrically connected to a control end of the first switch, the control end of the second switch is electrically connected to a second end of the first switch and the signal processing circuit respectively, and a second end of the second switch is electrically connected to the load power supply node; a first resistor, one end of the first resistor being electrically connected to the first end of the first switch and the first power access node respectively, and the other end of the first resistor being electrically connected to the second end of the first switch; a second resistor, one end of the second resistor being electrically connected to the second end of the first switch, and the other end of the second resistor being electrically connected to the signal processing circuit; a third resistor, one end of the third resistor being electrically connected to the first end of the first switch, and the other end of the third resistor being electrically connected to the control end of the first switch.

3. The seat fan driving circuit according to claim 1, characterized in that: The second enabling circuit comprises: A fourth resistor, one end of the fourth resistor is electrically connected to the signal processing circuit, and the other end of the fourth resistor is electrically connected to the load power supply node.

4. The seat fan driving circuit according to any one of claims 1 to 3, characterized in that: The signal processing circuit comprises: A signal input terminal, used for receiving the driving signal; a third switch, wherein a control end of the third switch is electrically connected to the signal input end, a first end of the third switch is electrically connected to a ground node, and a second end of the third switch is electrically connected to one end of the drive circuit; a fifth resistor, one end of the fifth resistor being electrically connected to the signal input end, and the other end of the fifth resistor being electrically connected to the control end of the third switch; A sixth resistor, one end of the sixth resistor is electrically connected to the other end of the fifth resistor and the control end of the third switch respectively, and the other end of the sixth resistor is electrically connected to the first end of the third switch and the ground node respectively.

5. The seat fan driving circuit according to claim 4, characterized in that: Also includes: A first protection circuit, wherein the first protection circuit comprises a seventh resistor and a first capacitor, wherein: One end of the seventh resistor is electrically connected to the other end of the driving circuit, and the other end of the seventh resistor is electrically connected to the load power supply node; One end of the first capacitor is electrically connected to the other end of the seventh resistor and the load power supply node respectively, and the other end of the first capacitor is electrically connected to the ground node.

6. The seat fan driving circuit according to claim 5, characterized in that: Also includes: A voltage detection output terminal for detecting the voltage of the load power supply node; A second protection circuit, wherein the second protection circuit comprises an eighth resistor, a ninth resistor, a tenth resistor and a second capacitor, wherein: One end of the eighth resistor is electrically connected to the other end of the driving circuit and one end of the seventh resistor; One end of the ninth resistor is electrically connected to the other end of the eighth resistor, and the other end of the ninth resistor is electrically connected to the ground node; One end of the tenth resistor is electrically connected to the connection node between the eighth resistor and the ninth resistor, and the other end of the tenth resistor is electrically connected to the voltage detection output terminal; A second capacitor, one end of the second capacitor is electrically connected to the other end of the tenth resistor and the voltage detection output end respectively, and the other end of the second capacitor is electrically connected to the ground node.

7. The seat fan driving circuit according to claim 6, characterized in that: The second protection circuit further includes: an eleventh resistor, one end of the eleventh resistor being electrically connected to the second power supply access node; A fourth switch, wherein a first end of the fourth switch is electrically connected to the other end of the eleventh resistor and the voltage detection node respectively, a control end of the fourth switch is electrically connected to the other end of the tenth resistor, and a second end of the fourth switch is electrically connected to the ground node.

8. The seat fan driving circuit according to claim 7, characterized in that: Also includes: An alarm circuit is electrically connected to the voltage detection output terminal, and the alarm circuit performs an acoustic alarm and / or an optical alarm when the voltage at the voltage detection output terminal is greater than a preset threshold.

9. A seat ventilation system, characterized in that: include: A seat fan drive circuit as claimed in any one of claims 1 to 8.

10. A vehicle, characterized in that: include: The seat ventilation system as claimed in claim 9.

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