Automobile glass lifting switch circuit with stall protection and control method thereof

Abstract

The present application relates to the field of automotive electronics, and in particular to an automotive glass lifting switch circuit with stall protection and a control method thereof, which includes a switch module for controlling the on and off of the circuit for a user and outputting a corresponding switch signal; a control module for receiving the switch signal and controlling the forward or reverse rotation of the motor according to the switch signal; and a stall protection module for detecting whether the motor is stalled and outputting a corresponding stall signal to the switch module to achieve on and off control. The present application has the effect of reducing costs.

Description

Technical Field

[0001] The present application relates to the field of automotive electronics, and in particular to an automotive window lift switch circuit with stall protection and a control method thereof. Background Art

[0002] In today's vehicles, it is very common to be equipped with automobile glass lifting switch circuits. Through the automobile glass lifting switch circuit, the user can control the automatic lifting of the automobile glass by pressing a button, without having to control the lifting of the automobile glass through a hand crank as before. The current automobile glass lifting switch circuit is mainly composed of a motor, a single-chip microcomputer, a power chip, a relay, a button, and a number of resistors, capacitors, diodes, transistors, etc. When the user presses the button, the relay is driven by the transistor, and the motor is turned on by the relay to control the lifting or lowering of the automobile glass. When the automobile glass is lifted and lowered to the point where it can no longer move, the motor is blocked and the current will increase. At this time, the current is collected through the pins of the single-chip microcomputer. After calculation and judgment, the single-chip microcomputer will control the transistor to open the circuit to achieve blocking protection, and the input power of the single-chip microcomputer is stabilized through the power chip.

[0003] However, the circuit of the conventional automobile window lifting switch is complicated, and the components such as the single-chip microcomputer and the power chip are expensive, the number of components is large, and the cost is high. Summary of the invention

[0004] In order to improve the problem of high cost of automobile glass lifting switch circuits, the present application provides an automobile glass lifting switch circuit with stall protection and a control method thereof.

[0005] The present application provides a car window lift switch circuit with stall protection, which adopts the following technical solution:

[0006] A car window lifting switch circuit with stall protection, comprising:

[0007] The switch module is used for users to control the on and off of the circuit and output the corresponding switch signal;

[0008] A control module receives a switch signal and controls the forward or reverse rotation of the motor according to the switch signal;

[0009] The stall protection module is used to detect whether the motor is stalled and output a corresponding stall signal to the switch module to achieve on-off control.

[0010] By adopting the above technical solution, the user's operation is detected by the switch module, and the corresponding switch signal is output to the control module, so as to control the forward and reverse rotation of the motor. Then, the stall protection module is used to protect the motor from stalling when the car glass has been raised or lowered to the specified position.

[0011] Optionally, the switch module includes a power supply terminal V bat , button SW1, network terminal V FB , transistor Q1, diode D1, diode D2, the third pin of the button SW1 is electrically connected to the power supply terminal V bat The third pin of the button SW1 is electrically connected to the first pin, the second pin, the fourth pin, and the fifth pin as the user presses and switches. The second pin and the fifth pin of the button SW1 are connected in parallel to the positive electrode of the diode D1. The first pin and the fourth pin of the button SW1 are connected in parallel to the positive electrode of the diode D2. The cathodes of the diodes D1 and D2 are connected in parallel to the network terminal V FB The diode D1 and the diode D2 are used to prevent reverse flow. FB The output end of the stall protection module is connected in parallel to the base of the transistor Q1, and the collector of the transistor Q1 is electrically connected to the control module to control the control module.

[0012] By adopting the above technical solution, the user can generate different current directions by turning the button SW1, thereby outputting different switch signals. The current direction is limited by diodes D1 and D2 to protect the current, reduce the current direction conflict that causes the normal operation to be unable to work, and improve stability.

[0013] Optionally, the control module includes a relay RY1 and a motor M, the relay RY1 includes at least two input terminals and at least two output terminals corresponding to the input terminals, the fourth pin and the fifth pin of the button SW1 are respectively electrically connected to different input terminals of the relay RY1, the motor M is electrically connected to different output terminals of the relay RY1, and the two output terminals of the relay RY1 are connected in parallel as the output terminal L of the control module, and are electrically connected to the stall protection module.

[0014] By adopting the above technical solution, different current directions are received to switch different current directions of the motor M, thereby controlling the forward and reverse rotation of the motor M, and the structure is simple and reliable.

[0015] Optionally, the control module also includes a diode D3 and a diode D5, the anode of the diode D3 is electrically connected to the fifth pin of the button SW1, the anode of the diode D5 is electrically connected to the fourth pin of the button SW1, and the cathode of the diode D3 and the cathode of the diode D5 are connected in parallel to the collector of the transistor Q1.

[0016] By adopting the above technical solution, the diode D3 and the diode D5 play a freewheeling role, reducing the probability of damage to components caused by sudden disappearance of current, thereby playing a protective role.

[0017] Optionally, the stall protection module includes an operational amplifier U1A, a comparator U1B, a network terminal V FB , resistor R4, and power supply end, the resistor R4 is electrically connected to the output end of the control module as a current sampling, the non-inverting input end and the inverting input end of the operational amplifier U1A are electrically connected to the two ends of the resistor R4, the output end and the inverting input end of the operational amplifier U1A are electrically connected to form a feedback network, the output end of the operational amplifier U1A is electrically connected to the reverse input end of the comparator U1B, the non-inverting input end of the comparator U1B is electrically connected to the power supply end, and the output end of the comparator U1B is electrically connected to the base of the transistor Q1.

[0018] By adopting the above technical solution, the current of the motor M is sampled through the resistor R4, the sampled current or voltage is amplified through the operational amplifier U1A, and then the amplified current or voltage is compared with the reference current or voltage through the comparator U1B, and the transistor Q1 is controlled by the output of the comparator U1B, thereby controlling the relay RY1, so that the automobile glass lifting switch circuit can be realized through hardware, and does not need to be controlled by single-chip microcomputer programming, so that the problems of shortage of automotive chips, high cost, and software bugs are effectively solved.

[0019] Optionally, the stall protection module includes a transistor Q4, the output end of the comparator U1B is electrically connected to the base of the transistor Q4, and the network end V FB The transistor Q4 is electrically connected to the emitter, the collector of the transistor Q4 is electrically connected to the feedback network of the operational amplifier U1A, and the base and emitter of the transistor Q4 are electrically connected.

[0020] By adopting the above technical solution, the transistor Q1 is kept in the off state through the transistor Q4, so as to improve the circuit stability and reduce the probability of component damage caused by repeated switching of the circuit between the on and off states.

[0021] Optional, including:

[0022] The detection module is used to detect the inverting input terminal and the output terminal of the comparator U1B, and is also used to detect the output terminal of the control module, obtain the corresponding detection signal and perform calculation to obtain an alarm signal and output it to the user.

[0023] By adopting the above technical solution and performing detection through the detection module, users can find faulty components in time, thereby improving safety.

[0024] A control method provided in this application adopts the following technical solution:

[0025] A control method, comprising:

[0026] Receive a switch signal;

[0027] Determine the direction of rotation of the motor by means of the switch signal;

[0028] Sampling the current of the motor to obtain a sampling signal;

[0029] A stall signal is determined by the sampling signal and a preset threshold signal, and whether to stop the motor operation is determined by the stall signal.

[0030] By adopting the above technical solution, the motor stall protection can be realized without using a chip, thereby reducing costs.

[0031] Optional, including:

[0032] Detecting the inverting input terminal and the output terminal of the comparator U1B, detecting the output terminal of the control module, and obtaining the detection signal, wherein the detection signal includes a detection input voltage, a detection output voltage, and a sampling current;

[0033] By comparing the detected input voltage with the preset inverting input threshold, it is determined whether the output terminal of the comparator U1B should be triggered in theory; by comparing the detected output voltage with the preset output trigger threshold, it is determined whether the output terminal of the comparator U1B is triggered, and a corresponding alarm signal is output to the user.

[0034] By adopting the above technical solution, users can detect faulty components in time, thereby improving safety.

[0035] Optionally, also include:

[0036] If the sampling current exceeds the preset stall threshold, and the detection input voltage exceeds the inverting input threshold, and the detection output voltage does not reach the output trigger threshold, an alarm signal indicating that the comparator U1B is abnormal is output to the user; if the sampling current exceeds the stall threshold, and the detection input voltage does not reach the inverting input threshold, and the detection output voltage does not reach the output trigger threshold, an alarm signal indicating that the operational amplifier U1A is abnormal is output to the user;

[0037] Preset a fluctuation threshold, determine the fluctuation time data by the sampled current and the fluctuation threshold, and if the fluctuation time data is greater than the preset fault time threshold, output an alarm signal indicating that the components of the switch module used for anti-reverse are abnormal to the user;

[0038] The number of fluctuations is determined by the fluctuation time data, the fault time threshold and the preset time interval threshold. If the number of fluctuations is greater than the preset fluctuation threshold, an alarm signal indicating that a component of the control module used to control forward or reverse rotation of the motor is abnormal is output to the user.

[0039] By adopting the above technical solution, it is possible to more accurately determine which component is damaged and output it to the user, thereby improving accuracy and further facilitating maintenance for the user.

[0040] In summary, the present application includes at least one of the following beneficial technical effects:

[0041] 1. The automobile window lifting switch circuit can be realized through hardware, without the need for single-chip microcomputer programming to control, so that the problems of shortage of automotive chips, high cost and software bugs are effectively solved.

[0042] 2. Implemented through hardware, the structure is simple and reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 This is a module schematic diagram of an automobile window lifting switch circuit with stall protection in Example 1 of the present application.

[0044] Figure 2 It is a circuit diagram of the switch module and the control module.

[0045] Figure 3 This is the circuit diagram of the stall protection module.

[0046] Figure 4 It is a schematic diagram of a process of controlling amplification in Example 1 of the present application.

[0047] Figure 5 This is a module schematic diagram of an automobile window lifting switch circuit with stall protection in Example 2 of the present application.

[0048] Figure 6 It is a schematic diagram of a process of controlling amplification in Example 2 of the present application.

[0049] Explanation of reference numerals: 1. switch module; 11. control module; 12. stall protection module; 13. detection module. DETAILED DESCRIPTION

[0050] The following is combined with Figure 1-6 This application is described in further detail.

[0051] Embodiment 1 of the present application discloses a car window lift switch circuit with stall protection. Figure 1The automobile window lifting switch circuit with stall protection includes a switch module 1, a control module 11 and a stall protection module 12. The switch module 1 is used to interact with the user and form a switch signal. The output end of the switch module 1 outputs the switch signal to the input end of the control module 11. The control module 11 controls the motor to perform corresponding forward or reverse rotation, and outputs the current of the motor as the output end to the stall protection module 12. The stall protection module 12 is used to sample the current to determine whether the motor is stalled, and output the corresponding stall signal to the switch module 1 to realize the on-off control of the motor.

[0052] Reference Figure 2 and Figure 3 , the switch module 1 includes a power supply terminal V bat , button SW1, network terminal V FB , transistor Q1, diode D1, diode D2, diode D4, capacitor C1, capacitor CE1, resistor R7, resistor R8, resistor R9. In this embodiment, capacitor CE1 can be an electrolytic capacitor for filtering and energy storage, and capacitor C1 is used for filtering; the third pin of button SW1 is the input terminal, the first pin, the second pin, the fourth pin, and the fifth pin of button SW1 are the output terminals, and the third pin of button SW1 can be electrically connected to any one of the first pin, the second pin, the fourth pin, and the fifth pin as the user turns it; resistor R7 is a pull-up resistor, resistor R8 is a current limiting resistor, and resistor R9 is a pull-down resistor; diode D1, diode D2, and diode D4 are used for current reverse protection, and transistor Q1 can be of NPN type. Power supply terminal V bat It is electrically connected to the positive electrode of diode D4, the negative electrode of diode D4 is electrically connected to the third pin of button SW1, and a +12V power supply terminal is connected in parallel between the negative electrode of diode D4 and the third pin of button SW1. The positive electrode of capacitor CE1 and one end of capacitor C1 are both connected in parallel between the negative electrode of diode D4 and the third pin of button SW1, and the negative electrode of capacitor CE1 and the other end of capacitor C1 are connected in parallel to ground. The first pin of button SW1 is connected in parallel to the fourth pin, and the second pin of button SW1 is connected in parallel to the fifth pin. The positive electrode of diode D1 is connected in parallel to the fifth pin of button SW1, the positive electrode of diode D2 is connected in parallel to the fourth pin of button SW1, and the negative electrode of diode D1 and the negative electrode of diode D2 are connected in parallel to the network terminal V FB One end of the resistor R8 is electrically connected to the base of the transistor Q1, one end of the resistor R7 is connected in parallel to the other end of the resistor R8, and the network terminal V FB The resistor R9 is electrically connected to the other end of the resistor R7. The resistor R9 is connected in parallel between the base and the emitter of the transistor Q1. The emitter of the transistor Q1 is grounded.

[0053] Reference Figure 2 and Figure 3The control module 11 includes a diode D3, a diode D5, a relay RY1, a motor M, a power supply terminal V bat , output terminal L, in this embodiment, the relay RY1 includes two input terminals and two output terminals, the two input terminals are respectively a first input terminal with a fourth pin and a fifth pin, and a second input terminal with a ninth pin and a tenth pin. The two output terminals are respectively a first output terminal with a first pin, a second pin, and a third pin, and a second output terminal with a sixth pin, a seventh pin, and an eighth pin. The first output terminal corresponds to the first input terminal, and the second output terminal corresponds to the second input terminal. With the conduction of the first output terminal, the first pin of the first input terminal can be moved to be electrically connected to either the second pin or the third pin, and with the conduction of the second output terminal, the sixth pin of the second input terminal can be moved to be electrically connected to either the seventh pin or the eighth pin; diodes D3 and D5 are used for freewheeling. The fifth pin of the button SW1 is electrically connected to the fifth pin of the relay RY1, and the fourth pin of the button SW1 is electrically connected to the ninth pin of the relay RY1. The cathode of diode D3 is connected in parallel between the fifth pin of button SW1 and the fifth pin of relay RY1, the cathode of diode D5 is connected in parallel between the fourth pin of button SW1 and the ninth pin of relay RY1, the anode of diode D3 is connected in parallel to the fourth pin of relay RY1, the anode of diode D5 is connected in parallel to the tenth pin of relay RY1, and the anode of diode D3 and the anode of diode D5 are connected in parallel to the collector of transistor Q1. Motor M is connected in series between the first pin and the sixth pin of relay RY1, the second pin and the seventh pin of relay RY1 are connected in parallel to output terminal L, and the third pin and the eighth pin of relay RY1 are connected in parallel to the power supply terminal V bat superior.

[0054] Reference Figure 2 and Figure 3The stall protection module 12 includes a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a resistor R6, a resistor R10, a resistor R11, an operational amplifier chip U1, a +12V power supply terminal, a transistor Q4, a diode D6, and a +12V power supply terminal. In this embodiment, the operational amplifier chip U1 includes an operational amplifier U1A and a comparator U1B. The operational amplifier chip U1 can adopt the LM2904DR model. One end of the resistor R4 is electrically connected to the output terminal L, and the other end of the resistor R4 is grounded. The resistor R4 is used to perform current sampling on the motor M. The in-phase input terminal of the operational amplifier U1A is connected in parallel between the resistor R4 and the output terminal L, one end of the resistor R2 is electrically connected to the inverting input terminal of the operational amplifier U1A, and the other end of the resistor R2 is connected in parallel between the resistor R4 and the ground terminal GND. The output end of the operational amplifier U1A is electrically connected to the inverting input end of the comparator U1B, and the resistor R3 is connected in series between the output end of the operational amplifier U1A and the inverting input end of the comparator U1B. The resistor R3 is used for current limiting. One end of the resistor R5 is electrically connected to the +12V power supply end, one end of the resistor R6 is electrically connected to the other end of the resistor R5, and the other end of the resistor R6 is grounded. The in-phase input end of the comparator U1B is connected in parallel between the resistor R5 and the resistor R6. The resistors R5 and R6 form a voltage divider circuit to provide a reference voltage to the comparator U1B, or to provide a reference voltage to the operational amplifier chip U1. One end of the resistor R1 is connected in parallel between the resistor R2 and the inverting input end of the operational amplifier U1A, and the other end of the resistor R1 is connected in parallel between the output end of the operational amplifier U1A and the resistor R3. The resistors R1 and R2 form an operational amplifier feedback network. The output end of the comparator U1B is electrically connected between the resistor R7 and the resistor R8 as the RelayCtrl end to control the transistor Q1. The output end of the comparator U1B is electrically connected to the base of the transistor Q4, the resistor R11 is connected in series between the output end of the comparator U1B and the base of the transistor Q4, and the emitter of the transistor Q4 is electrically connected to the network terminal V FB The resistor R10 is connected in parallel between the emitter and base of the transistor Q4, the collector of the transistor Q4 is electrically connected to the anode of the diode D6, the cathode of the diode D6 is connected in parallel between the output end of the operational amplifier U1A and the resistor R3, and the diode D6 is used for reverse protection.

[0055] The implementation principle of the automobile glass lifting switch circuit with stall protection in the first embodiment of the present application is as follows: when the user pushes the third pin of the button SW1 and the fifth pin is electrically connected, the power supply terminal V bat The input power passes through diode D4 and diode D1 to the network terminal V FB , network end V FBThe transistor Q1 is turned on, so that the first pin of the relay RY1 is moved to be electrically connected to the third pin and turned on, and the sixth pin of the relay RY1 is moved to be electrically connected to the seventh pin and turned on, the motor rotates forward, and the current of the motor is sampled through the resistor R4 to the operational amplifier U1A, and then amplified by the operational amplifier U1A and output to the inverting input terminal of the comparator U1B. When the amplified current is greater than the voltage divided value of the +12V power supply terminal on the resistor R5 and the resistor R6, the RelayCtrl terminal outputs a low level, the transistor Q1 is turned off, and the transistor Q4 is kept in a turned-off state to achieve stall protection;

[0056] When the user pushes the third pin of the key SW1 and the fourth pin is electrically connected, the power supply terminal V bat The input power passes through diode D4 and diode D1 to the network terminal V FB , network end V FB The transistor Q1 is turned on, so that the first pin of the relay RY1 is moved to be electrically connected to the second pin and the sixth pin of the relay RY1 is moved to be electrically connected to the eighth pin and the motor is reversed.

[0057] Embodiment 1 of the present application discloses a control method. Figure 1 , control methods include:

[0058] S1, receiving switch signal;

[0059] S11, determining the direction of the motor through the switch signal;

[0060] S12, sampling the current of the motor to obtain a sampling signal;

[0061] S13, determining a stall signal through the sampling signal and a preset threshold signal, and determining whether to stop the motor operation through the stall signal.

[0062] For example: the user presses the third pin of the button SW1 to electrically connect the fourth pin or the fifth pin, so that different pins of the relay RY1 are turned on, that is, different switching signals are obtained, which will cause different directions of the motor to work, that is, forward or reverse. The voltage at the non-inverting input terminal of the comparator U1B is the reference voltage, which is the threshold signal in step S13.

[0063] Embodiment 2:

[0064] Embodiment 2 of the present application discloses a vehicle window lift switch circuit with stall protection, which is different from Embodiment 1 in that: Figure 5The automobile glass lifting switch circuit with stall protection includes a detection module 13. In this embodiment, the detection module 13 uses a chip with a voltage detection function. Since it does not have a control function, the price is still low compared to the original single-chip microcomputer. The detection module 13 is used to detect the inverting input and output ends of the comparator U1B, and is also used to detect the output end of the control module 11, obtain the corresponding detection signal and perform calculation, and obtain an alarm signal to output to the user.

[0065] Embodiment 2 of the present application discloses a control method. Figure 6 , control methods include:

[0066] S2, detect the inverting input terminal and output terminal of the comparator U1B, detect the output terminal of the control module 11, and obtain a detection signal, which includes a detection input voltage, a detection output voltage, and a sampling current;

[0067] S21, determining whether the output terminal of the comparator U1B should be triggered theoretically by comparing the detected input voltage with the preset inverting input threshold, determining whether the output terminal of the comparator U1B is triggered by comparing the detected output voltage with the preset output trigger threshold, and outputting a corresponding alarm signal to the user;

[0068] S22, if the sampling current exceeds the preset stall threshold, and the detection input voltage exceeds the inverting input threshold, and the detection output voltage does not reach the output trigger threshold, an alarm signal indicating that the comparator U1B is abnormal is output to the user; if the sampling current exceeds the stall threshold, and the detection input voltage does not reach the inverting input threshold, and the detection output voltage does not reach the output trigger threshold, an alarm signal indicating that the operational amplifier U1A is abnormal is output to the user;

[0069] S23, preset a fluctuation threshold, determine the fluctuation time data by sampling the current and the fluctuation threshold, and if the fluctuation time data is greater than the preset fault time threshold, output an alarm signal indicating that the components used for anti-reverse of the switch module 1 are abnormal to the user;

[0070] S24, determining the number of fluctuations by means of the fluctuation time data, the fault time threshold and the preset time interval threshold; if the number of fluctuations is greater than the preset fluctuation threshold, outputting an alarm signal indicating that the components used by the control module 11 to control the forward or reverse rotation of the motor are abnormal to the user.

[0071] For example: the voltage at the inverting input terminal of the comparator U1B is the detection input voltage, the voltage at the output terminal of the comparator U1B is the detection output voltage, and the sampling current is the current sampled on the resistor R4; the stall threshold is set to 10A, the reverse input threshold is set to 6V, and the output trigger threshold is set to 0V. If the detection output voltage is 6.5V, and the detection output voltage is 3V greater than 0V, and the sampling current is 12A greater than 10A, it means that the motor is normally stalled, the operational amplifier U1A works normally to amplify the voltage, but the comparator U1B does not work normally and is not triggered, and an alarm signal indicating that the comparator U1B is abnormal is output to the user; if the sampling current is 12A, and the detection input voltage is 2V<6A, it means that the motor is normally stalled, but the operational amplifier U1A does not work normally to amplify the voltage, and an alarm signal indicating that the operational amplifier U1A is abnormal is output to the user;

[0072] Assume that the fluctuation threshold is 2A, and the fault time threshold is 2s. If the user has correctly pressed the button SW1, the sampling current is 0A<2A and lasts for 10s. The fluctuation time data is 10s>2s. This indicates that the motor M is not working properly or is working properly but is continuously idling. The motor M may not work properly because the diode D1 or the diode D2 fails to reverse, resulting in the first output terminal of the relay RY1 not being properly electrically connected to the second output terminal. For example, when the first pin is electrically connected to the second pin, the sixth pin is electrically connected to the seventh pin, resulting in the power supply terminal V bat It is not connected to the motor M, and a corresponding alarm signal is output to the user;

[0073] Assume that the time interval threshold is 2s, and the fluctuation threshold is 3. If the sampling current fluctuates from 0A to 4A within 2s, and then from 4A to 0A 5 times, the number of fluctuations is 5>3, which means that the motor M switches multiple times between forward and reverse rotation, that is, the first output terminal and the second output terminal of the relay RY1 switch frequently, and an alarm signal indicating that the relay RY1 is abnormal is output to the user.

[0074] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. A car window lift switch circuit with stall protection, characterized in that: include: A switch module (1), used for enabling a user to control the on and off of a circuit and outputting a corresponding switch signal; A control module (11) receives a switch signal and controls the forward or reverse rotation of the motor according to the switch signal; A stall protection module (12) is used to detect whether the motor is stalled and output a corresponding stall signal to the switch module (1) to achieve on-off control; The switch module (1) comprises a power supply terminal Vbat, a button SW1, a network terminal VFB, a transistor Q1, a diode D1, and a diode D2. The third pin of the button SW1 is electrically connected to the power supply terminal Vbat. The third pin of the button SW1 is electrically connected to the first pin, the second pin, the fourth pin, and the fifth pin as the user presses and slides the button SW1. The second pin and the fifth pin of the button SW1 are connected in parallel to the positive electrode of the diode D1. The first pin and the fourth pin of the button SW1 are connected in parallel to the positive electrode of the diode D2. The cathode of the diode D1 and the cathode of the diode D2 are connected in parallel to the network terminal VFB. The diode D1 and the diode D2 are used for reverse protection. The network terminal VFB and the output terminal of the stall protection module (12) are connected in parallel to the base of the transistor Q1. The collector of the transistor Q1 is electrically connected to the control module (11) to control the control module (11). A resistor R9 is connected in parallel between the base and the emitter of the transistor Q1. The emitter of the transistor Q1 is grounded. The control module (11) comprises a relay RY1 and a motor M, the relay RY1 comprising at least two input terminals and at least two output terminals corresponding to the input terminals, the fourth pin and the fifth pin of the button SW1 are respectively electrically connected to different input terminals of the relay RY1, the motor M is electrically connected to different output terminals of the relay RY1, and the two output terminals of the relay RY1 are connected in parallel as an output terminal L of the control module (11) and are electrically connected to the stall protection module (12); The control module (11) further comprises a diode D3 and a diode D5, wherein the cathode of the diode D3 is electrically connected to the fifth pin of the key SW1, the cathode of the diode D5 is electrically connected to the fourth pin of the key SW1, and the anode of the diode D3 and the anode of the diode D5 are connected in parallel to the collector of the transistor Q1; The stall protection module (12) comprises an operational amplifier U1A, a comparator U1B, a network terminal VFB, a resistor R4, and a power supply terminal, wherein the resistor R4 is electrically connected to the output terminal of the control module (11) as a current sampling terminal, the non-inverting input terminal and the inverting input terminal of the operational amplifier U1A are electrically connected to the two ends of the resistor R4, the output terminal and the inverting input terminal of the operational amplifier U1A are electrically connected to form a feedback network, the output terminal of the operational amplifier U1A is electrically connected to the inverting input terminal of the comparator U1B, the non-inverting input terminal of the comparator U1B is electrically connected to the power supply terminal, and the output terminal of the comparator U1B is electrically connected to the base of the transistor Q1; The stall protection module (12) further comprises a transistor Q4, the output end of the comparator U1B is electrically connected to the base of the transistor Q4, the network end VFB is electrically connected to the emitter of the transistor Q4, the collector of the transistor Q4 is electrically connected to the feedback network of the operational amplifier U1A, and the base and emitter of the transistor Q4 are electrically connected.

2. The automobile window lifting switch circuit with stall protection according to claim 1, characterized in that: include: The detection module (13) is used to detect the inverting input terminal and the output terminal of the comparator U1B, and is also used to detect the output terminal of the control module (11), obtain a corresponding detection signal and perform calculations to obtain an alarm signal and output it to the user.

3. A control method, using the automobile window lifting switch circuit with stall protection according to any one of claims 1 to 2, characterized in that: include: Receive a switch signal; Determine the direction of rotation of the motor by means of the switch signal; Sampling the current of the motor to obtain a sampling signal; A stall signal is determined by the sampling signal and a preset threshold signal, and whether to stop the motor operation is determined by the stall signal.

4. A control method according to claim 3, characterized in that: include: Detecting the inverting input terminal and the output terminal of the comparator U1B, detecting the output terminal of the control module (11), and obtaining the detection signal, wherein the detection signal includes a detection input voltage, a detection output voltage, and a sampling current; By comparing the detected input voltage with the preset inverting input threshold, it is determined whether the output terminal of the comparator U1B should be triggered in theory; by comparing the detected output voltage with the preset output trigger threshold, it is determined whether the output terminal of the comparator U1B is triggered, and a corresponding alarm signal is output to the user.

5. A control method according to claim 4, characterized in that: After getting the detection signal, it also includes: If the sampling current exceeds the preset stall threshold, and the detection input voltage exceeds the inverting input threshold, and the detection output voltage does not reach the output trigger threshold, an alarm signal indicating that the comparator U1B is abnormal is output to the user; If the sampling current exceeds the stall threshold, and the detection input voltage does not reach the inverting input threshold, and the detection output voltage does not reach the output trigger threshold, an alarm signal indicating that the operational amplifier U1A is abnormal is output to the user; A fluctuation threshold is preset, and fluctuation time data is determined by the sampled current and the fluctuation threshold. If the fluctuation time data is greater than a preset fault time threshold, an alarm signal indicating that a component of the switch module (1) used for preventing reverse flow is abnormal is output to a user; The number of fluctuations is determined by the fluctuation time data, the fault time threshold and a preset time interval threshold. If the number of fluctuations is greater than the preset fluctuation threshold, an alarm signal indicating that a component of the control module (11) used to control forward or reverse rotation of the motor is abnormal is output to a user.

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