Loudspeaker diagnosis protection circuit and vehicle

Abstract

The utility model provides a loudspeaker diagnosis protection circuit and a vehicle, and is applied to the technical field of loudspeakers, the circuit comprises an MCU, a loudspeaker driving module and a loudspeaker, two working branch lines are connected between the loudspeaker driving module and the loudspeaker, each working branch line is provided with a switch module, the switch module is connected with the MCU, and the MCU is connected with the loudspeaker driving module. One working branch line is provided with a diagnosis power supply node, the other working branch line is provided with a diagnosis node, and the diagnosis power supply node and the diagnosis node are both located between the switch module and the loudspeaker; wherein the diagnosis power supply node and the diagnosis node are respectively connected with the MCU; and when the switch module is in a turn-off state, the MCU supplies power to the diagnosis power supply node, and the MCU is conducted with the diagnosis node, so that the circuit fault of the loudspeaker can be found and diagnosed in time while the loudspeaker is not damaged.

Description

Technical Field

[0001] The utility model relates to the technical field of loudspeakers, in particular to a loudspeaker diagnosis protection circuit and a vehicle. Background Art

[0002] In order to ensure that the speaker can work stably in various environments, it needs to be effectively controlled and diagnosed. Traditional speaker control systems are usually only able to perform basic on / off control and lack the ability to monitor and diagnose the speaker status in real time. In addition, when the speaker faces a circuit short circuit or overvoltage, traditional systems often lack effective protection and diagnostic measures, which may cause damage to the speaker or related electronic equipment and the cause of the damage cannot be obtained in time. Utility Model Content

[0003] In view of this, the purpose of the present invention is to provide a speaker diagnosis protection circuit and a vehicle to solve the problem of speaker damage caused by lack of effective protection and diagnosis measures for the speaker status.

[0004] Based on the above purpose, the utility model provides a speaker diagnosis protection circuit, including an MCU, a speaker driving module and a speaker, wherein two working branches are connected between the speaker driving module and the speaker, and each of the working branches is provided with a switch module, wherein one of the working branches is provided with a diagnostic power supply node, and the other working branch is provided with a diagnostic node, and the diagnostic power supply node and the diagnostic node are both located between the switch module and the speaker;

[0005] Wherein, the diagnostic power supply node and the diagnostic node are respectively connected to the MCU;

[0006] When the switch module is in the off state, the MCU supplies power to the diagnosis power supply node, and the MCU is connected to the diagnosis node.

[0007] Furthermore, the switch module includes an overvoltage protection circuit and a MOS tube, and an overvoltage detection node is also provided on the working branch line, the overvoltage detection node is located between the MOS tube and the speaker, and the overvoltage detection node is connected to the gate of the MOS tube through the overvoltage protection circuit;

[0008] When the overvoltage detection node is connected to the overvoltage protection circuit, the MOS tube is turned off.

[0009] Further, the overvoltage protection circuit includes a first transistor, the base of the first transistor is connected to the overvoltage detection node, and the collector is connected to the gate of the MOS transistor;

[0010] When the overvoltage detection node is connected to the base of the first transistor, the collector of the first transistor is connected to the gate of the MOS transistor.

[0011] Furthermore, the switch module includes a switch circuit and a MOS tube, and the MCU is connected to the gate of the MOS tube through the switch circuit;

[0012] When the MCU inputs a preset level to the switch circuit, the MOS tube is turned on.

[0013] Further, the switch circuit includes a second triode and a third triode, and the collector of the second triode is connected to the base of the third triode;

[0014] Wherein, the base of the second triode is connected to the MCU, the emitter of the third triode is connected to the MCU, and the collector of the third triode is connected to the gate of the MOS tube;

[0015] When the MCU inputs a preset level to the base of the second transistor, the collector of the second transistor is connected to the base of the third transistor, and the collector of the third transistor is connected to the gate of the MOS transistor.

[0016] Furthermore, another diagnostic node is provided on the working branch line where the diagnostic power supply node is located, and the other diagnostic node is located between the switch module and the speaker and is connected to the MCU;

[0017] When the switch module is in the off state, the MCU supplies power to the diagnostic power supply node, and the MCU is connected to all diagnostic nodes.

[0018] Furthermore, a unidirectional diode is provided between the MCU and the diagnosis power supply node, the MCU is connected to the anode of the unidirectional diode, and the diagnosis power supply node is connected to the cathode of the unidirectional diode.

[0019] Furthermore, the MOS tube includes an NMOS tube, a drain of the NMOS tube is connected to the speaker driving module, and a source of the NMOS tube is connected to the speaker.

[0020] Furthermore, a first resistor is provided between the base of the first transistor and the overvoltage detection node, a second resistor is connected in parallel between the base and the emitter of the first transistor, and a common end of the second resistor and the emitter of the first transistor is grounded.

[0021] The utility model also provides a vehicle, comprising the speaker diagnosis protection circuit as described in any of the above items.

[0022] From the above description, it can be seen that the speaker diagnostic protection circuit and vehicle provided by the utility model, wherein the circuit includes: an MCU, a speaker driving module and a speaker, two working branches are connected between the speaker driving module and the speaker, and each of the working branches is provided with a switch module for controlling the on and off of the working branches through the on and off of the switch module, wherein one of the working branches is provided with a diagnostic power supply node, and the other working branch is provided with a diagnostic node, and the diagnostic power supply node and the diagnostic node are both located between the switch module and the speaker; wherein the diagnostic power supply node and the diagnostic node are respectively connected to the MCU; when the switch module is in When in the shutdown state, the MCU supplies power to the diagnostic power supply node, the MCU is turned on with the diagnostic node, and the MCU obtains the voltage of the diagnostic node. If the voltage of the diagnostic node is equal to the voltage supplied by the MCU to the diagnostic power supply node, it indicates that the speaker is in place. If the voltage of the diagnostic node is greater than the voltage supplied by the diagnostic power supply node, it indicates that the speaker is not in place and the working branch line may be short-circuited with the power supply. If the voltage of the diagnostic node is zero, it indicates that the speaker is not in place. When it is determined that the speaker is in place, the switch module can be turned on and the speaker works normally. When it is determined that the speaker is not in place, the circuit needs to be repaired according to the determined fault to ensure the normal operation of the speaker. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 The principle of the speaker diagnosis protection circuit in the embodiment of the utility model Figure 1 ;

[0025] Figure 2 The principle of the speaker diagnosis protection circuit in the embodiment of the utility model Figure 2 ;

[0026] Figure 3 This is a schematic diagram of the connection relationship of the overvoltage protection circuit in the embodiment of the utility model;

[0027] Figure 4 This is an exemplary circuit of the overvoltage protection circuit in the embodiment of the utility model Figure 1 ;

[0028] Figure 5 This is an exemplary circuit of the overvoltage protection circuit in the embodiment of the utility model Figure 2 ;

[0029] Figure 6 A schematic diagram of the connection relationship of the switch circuit in the embodiment of the utility model;

[0030] Figure 7 is an exemplary circuit diagram of a switch circuit in an embodiment of the present utility model;

[0031] Figure 8 This is a schematic diagram of the connection relationship of the unidirectional diode in the embodiment of the utility model;

[0032] Fig. 9 It is an exemplary circuit diagram of T-BOX in an embodiment of the utility model.

[0033] In the figure, 10, MCU, 20, speaker drive module, 30, speaker, 40, switch module, 51, diagnostic power supply node, 52, diagnostic node, 53, diagnostic node, 41, overvoltage protection circuit, 42, switch circuit, 54, overvoltage detection node, 60, MOS tube, 71, first transistor, 72, second transistor, 73, third transistor, 81, first resistor, 82, second resistor, 90, unidirectional diode, 91, communication module. DETAILED DESCRIPTION

[0034] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments and with reference to the accompanying drawings.

[0035] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the embodiments of the utility model should be the common meanings understood by people with ordinary skills in the field to which the disclosure belongs. The "first", "second" and similar words used in the present disclosure do not represent any order, quantity or importance, but are only used to distinguish different components. "Including" or "comprising" and similar words mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0036] In the related art, speakers are widely used as output devices in many fields such as in-vehicle infotainment systems and warning systems. The normal operation of speakers is crucial to the accuracy and reliability of sound signals. However, speakers may encounter various problems during use, such as short circuits, open circuits, or improper installation, which will affect the normal function of the speakers.

[0037] Traditional speaker control systems are usually only capable of basic on / off control and lack the ability to monitor and diagnose the speaker status in real time. In addition, speakers often lack effective protection and diagnostic measures when facing circuit short circuits or overvoltage conditions, resulting in damage to the speaker or related electronic equipment without being able to identify the cause of the damage in a timely manner.

[0038] In the process of solving the above technical problems, the applicant discovered that by setting a switch module and a diagnostic module between the speaker and the speaker driving module, the speaker's in-situ status can be detected before the speaker works to determine whether the speaker is faulty, or the speaker can be disconnected and then the speaker can be tested in-situ when the circuit is over-voltage or voltage is reversed. This can ensure that the speaker is not damaged while promptly discovering and diagnosing the speaker's circuit fault.

[0039] It should be noted that if Fig. 9 As shown, the speaker driving module 20 is arranged in the vehicle-mounted T-BOX, and the speaker driving module 20 is usually connected to the communication module 91 and the MCU10 in the vehicle-mounted T-BOX; when the communication module 91 receives a communication signal from the outside (for example, a Bluetooth signal from a smart phone), the communication module 91 parses the signal and sends the parsed data (such as audio data, instructions, etc.) to the speaker driving module 20, and the speaker driving module 20 converts it into a corresponding analog signal and amplifies the analog signal so as to be able to drive the speaker 30 to produce sound; when the MCU10 needs to issue a sound warning or notification (for example, a vehicle fault warning, a safety prompt, a navigation voice guidance, etc.), the MCU10 generates a corresponding sound signal, and after the speaker driving module 20 receives the sound signal generated by the MCU10, it converts it into a corresponding analog signal and amplifies the analog signal so as to be able to drive the speaker 30 to produce sound.

[0040] Based on this, the utility model provides a speaker diagnosis protection circuit, such as Figure 1 As shown, it includes an MCU 10, a speaker driving module 20 and a speaker 30, two working branches are connected between the speaker driving module 20 and the speaker 30, and each of the working branches is provided with a switch module 40, wherein one of the working branches is provided with a diagnostic power supply node 51, and the other working branch is provided with a diagnostic node 52, and the diagnostic power supply node 51 and the diagnostic node 52 are both located between the switch module 40 and the speaker 30 (in the embodiment of the present application, the VON pin of the speaker driving module 20 is connected to one working branch, and the VOP pin of the speaker driving module 20 is connected to the other working branch);

[0041] Wherein, the diagnostic power supply node 51 and the diagnostic node 52 are respectively connected to the MCU 10;

[0042] When the switch module 40 is in the off state, the MCU 10 supplies power to the diagnosis power supply node 51 , and the MCU 10 is connected to the diagnosis node 52 .

[0043] In a specific implementation, the speaker 30 is first diagnosed for its in-place status before it works, that is, when the switch module 40 is in the off state, the MCU 10 supplies power to the diagnostic power supply node 51 (in the embodiment of the present application, the VP_SPK_DET_EN pin of the MCU 10 is connected to the diagnostic power supply node 51 to supply power to the diagnostic power supply node 51), and at the same time, the MCU 10 is turned on with the diagnostic node 52 (in the embodiment of the present application, the VP_ADC_SPK_P pin of the MCU 10 is connected to the diagnostic node 52), and the MCU 10 obtains the diagnostic node If the voltage of the diagnostic node 52 is equal to the voltage supplied by the MCU 10 to the diagnostic power supply node 51, it indicates that the speaker 30 is in place. If the voltage of the diagnostic node 52 is greater than the voltage supplied by the diagnostic power supply node 51, it indicates that the speaker 30 is not in place and the working branch may be short-circuited with the power supply. If the voltage of the diagnostic node 52 is zero, it indicates that the speaker 30 is not in place. When it is determined that the speaker 30 is in place, the switch module 40 can be turned on and the speaker 30 works normally. When it is determined that the speaker 30 is not in place, the circuit needs to be repaired according to the determined fault.

[0044] In addition, a switching circuit and a MOS tube can be set in the switching module 40, and the MCU10 is connected to the gate of the MOS tube through the switching circuit; when the MCU10 inputs a corresponding level signal to the switching circuit, the switching circuit outputs a switching control signal to control the MOS tube to be turned on, and the speaker driving module 20 provides a driving signal to the speaker 30 to drive the speaker 30 to work.

[0045] An overvoltage protection circuit and a MOS tube can also be set in the switch module 40, and an overvoltage detection node can also be set on the working branch line. The overvoltage detection node is located between the MOS tube and the speaker, and the overvoltage detection node is connected to the gate of the MOS tube through the overvoltage protection circuit. When the voltage of the overvoltage detection node is greater than the threshold voltage of the overvoltage protection circuit, the overvoltage detection node is connected to the overvoltage protection circuit, and the overvoltage protection circuit controls the MOS tube to turn off by controlling the gate of the MOS tube, and the working branch line is disconnected to prevent the voltage from backflowing and damaging the speaker drive module, or to prevent the voltage from being too high to damage other devices on the working branch line. By detecting the overvoltage of the overvoltage detection node 54, the MOS tube is immediately turned off to prevent the excessive voltage from damaging the speaker drive module 20 or other devices on the working branch line, so as to effectively prevent the potential damage of the power supply overvoltage to the circuit system; by preventing overvoltage and voltage backflow, equipment damage is avoided, thereby extending the service life of the equipment.

[0046] The diagnostic power supply node 51 is powered by MCU10, and at the same time, MCU10 is connected to the diagnostic node 52 to obtain the voltage of the diagnostic node 52. Judging the voltage of the diagnostic node 52 and the voltage of the diagnostic power supply node 51 powered by MCU10 can determine whether the speaker 30 is in place and whether the working branch line is short-circuited with the power supply. If the voltage of the diagnostic node 52 is equal to the voltage of the diagnostic power supply node 51 powered by MCU10, it indicates that the speaker 30 is in place. If the voltage of the diagnostic node 52 is greater than the voltage of the diagnostic power supply node 51, it indicates that the speaker 30 is not in place and the working branch line is short-circuited with the power supply. The line may be short-circuited with the power supply. If the voltage of the diagnostic node 52 is zero, it indicates that the speaker 30 is not in place. When it is determined that the speaker 30 is in place, the switch module 40 can be turned on, and the speaker 30 works normally. When it is determined that the speaker 30 is not in place, it is necessary to repair the circuit according to the determined fault to ensure the normal operation of the speaker 30, improve the accuracy of fault diagnosis, avoid the decline in sound quality or sound interruption caused by the fault of the speaker 30, thereby optimizing the user experience. At the same time, maintenance personnel can find the fault problem more quickly and accurately, thereby reducing the maintenance cost and time of the speaker 30.

[0047] Furthermore, if Figure 2 As shown, based on the above embodiment, a diagnostic node 52 is added to more accurately judge the situation that the speaker 30 fails (the speaker is not in place), and another diagnostic node 53 is provided on the working branch line where the diagnostic power supply node 51 is located. The other diagnostic node 53 is located between the switch module 40 and the speaker 30, and is connected to the MCU 10 (in the embodiment of the present application, the VP_ADC_SPK N pin of the MCU 10 is connected to the diagnostic node 53);

[0048] When the switch module 40 is in the off state, the MCU 10 supplies power to the diagnosis power supply node 51 , and the MCU 10 is connected to all the diagnosis nodes.

[0049] In specific implementation, when the switch module 40 is in the off state, the MCU10 supplies power to the diagnostic power supply node 51, and at the same time, the MCU10 is connected to all diagnostic nodes to obtain the voltage of all diagnostic nodes. If the voltage of all diagnostic nodes is equal to the voltage supplied by the MCU10 to the diagnostic power supply node 51, it indicates that the speaker 30 is in place; if the voltage of all diagnostic nodes is zero, it indicates that the speaker 30 is not in place and the working branch is short-circuited to the ground; if the voltage of the diagnostic node 52 on the working branch where the diagnostic power supply node 51 is located is equal to the voltage supplied by the MCU10 to the diagnostic power supply node 51, and the voltage of the diagnostic node 53 on another working branch is zero, it indicates that the speaker 30 is not in place and the working branch is open.

[0050] The diagnostic power supply node 51 is powered by MCU10, and at the same time, MCU10 is connected to all diagnostic nodes 52 to obtain the voltage of all diagnostic nodes 52. At the same time, judging the voltage of all diagnostic nodes 52 and the voltage supplied by MCU10 to the diagnostic power supply node 51 can determine whether the speaker 30 is in place, the working branch line is short-circuited to the ground, and the working branch line is open, thereby further improving the accuracy of fault diagnosis, avoiding the decline in sound quality or sound interruption caused by the failure of the speaker 30, thereby optimizing the user experience, and at the same time, maintenance personnel can find the fault problem more quickly and accurately, thereby reducing the maintenance cost and time of the speaker 30.

[0051] Based on the above embodiment, two working branches are connected between the speaker driving module 20 and the speaker 30, and a switch module 40 is provided on each of the working branches; when the switch module 40 is in the off state, the MCU 10 supplies power to the diagnostic power supply node 51, and the MCU 10 is connected to the diagnostic node 52; in order to prevent damage to the equipment due to overvoltage and voltage backflow, the switch module 40 is described in detail through the following embodiments.

[0052] In some embodiments, Figure 3 As shown, the switch module 40 includes an overvoltage protection circuit 41 and a MOS tube 60, and an overvoltage detection node 54 is also provided on the working branch line. The overvoltage detection node 54 is located between the MOS tube 60 and the speaker 30, and the overvoltage detection node 54 is connected to the gate of the MOS tube 60 through the overvoltage protection circuit 41;

[0053] When the overvoltage detection node 54 is connected to the overvoltage protection circuit 41 , the MOS transistor 60 is turned off.

[0054] In specific implementation, when the voltage of the overvoltage detection node 54 is greater than the threshold voltage of the overvoltage protection circuit 41, the overvoltage detection node 54 is connected to the overvoltage protection circuit 41, and the overvoltage protection circuit 41 controls the MOS tube 60 to be turned off by controlling the gate of the MOS tube 60, and the working branch is disconnected to prevent voltage backflow from damaging the speaker drive module 20, or to prevent excessive voltage from damaging other devices on the working branch.

[0055] By detecting an overvoltage at the overvoltage detection node 54, the MOS tube 60 is immediately turned off to prevent excessive voltage from damaging the speaker drive module 20 or other devices on the working branch line, thereby effectively preventing potential damage to the circuit system caused by power overvoltage. By preventing overvoltage and voltage backflow, equipment damage is avoided, thereby extending the service life of the equipment. At the same time, since overvoltage and voltage backflow are common causes of equipment damage, the risk of equipment damage can be reduced by immediately turning off the MOS tube 60 when an overvoltage at the overvoltage detection node 54 is detected.

[0056] It should be noted that the MOS tube (metal oxide semiconductor field effect tube, MOSFET) is a semiconductor device that controls the flow of current by voltage. It is mainly composed of three parts: source, drain and gate. The gate is separated from the source and drain by an oxide layer (usually silicon dioxide) to form a capacitor. When an appropriate voltage is applied between the gate and the source, a conductive channel is formed on the semiconductor surface between the source and the drain, allowing current to flow. MOSFET can be N-type or P-type, depending on the doping type of its channel. The triode (bipolar transistor, BJT) with a similar function to the MOS tube is a current-controlled semiconductor device, including NPN type and PNP type, which consists of three parts: emitter, base and collector. In the NPN triode, when a forward voltage is applied between the base and the emitter, so that sufficient current is formed from the base to the emitter, the base current can control a larger current from the emitter to the collector. Compared with triodes, MOS tubes can achieve faster switching speeds, making MOS tubes more reliable in applications that require high-speed switching (such as modern power conversion equipment); secondly, MOS tubes usually have better thermal stability than triodes, and are more reliable in high-temperature applications. Moreover, since what is required to control the MOS tube is voltage rather than current, its driving circuit is relatively simple, which can reduce the design difficulty and cost. Therefore, in the embodiment of the present application, the switch module 40 includes an overvoltage protection circuit 41 and a MOS tube 60, and an overvoltage detection node 54 is also provided on the working branch line. The overvoltage detection node 54 is located between the MOS tube 60 and the speaker 30, and the overvoltage detection node 54 is connected to the gate of the MOS tube 60 through the overvoltage protection circuit 41; when the overvoltage detection node 54 is connected to the overvoltage protection circuit 41, the MOS tube 60 can be turned off more quickly to protect the equipment in the circuit in time. Secondly, the MOS tube has better thermal stability when the working branch line is overvoltage.

[0057] Based on the above embodiment, the overvoltage detection node 54 located between the MOS tube 60 and the speaker 30 is connected to the gate of the MOS tube 60 through the overvoltage protection circuit 41; when the overvoltage detection node 54 and the overvoltage protection circuit 41 are connected, the MOS tube 60 is turned off; in order to prevent the voltage from backflowing and damaging the speaker driving module 20, or to prevent the voltage from being too high and damaging other devices on the working branch line, the overvoltage protection circuit 41 is described in detail through the following embodiments.

[0058] Specifically, if Figure 4As shown, the overvoltage protection circuit 41 includes a first transistor 71, the base of the first transistor 71 is connected to the overvoltage detection node 54, and the collector is connected to the gate of the MOS transistor 60 (in the embodiment of the present application, the first transistor 71 is an NPN transistor);

[0059] When the overvoltage detection node 54 is connected to the base of the first transistor 71 , the collector of the first transistor 71 is connected to the gate of the MOS transistor 60 .

[0060] In specific implementation, when the voltage of the overvoltage detection node 54 is greater than the threshold voltage of the overvoltage protection circuit 41, the overvoltage detection node 54 is connected to the base of the first transistor 71, and the collector of the first transistor 71 is connected to the gate of the MOS tube 60. At this time, the MOS tube 60 is turned off and the working branch is disconnected, which can prevent the voltage from backflowing and damaging the speaker drive module 20, or prevent the voltage from being too high and damaging other devices on the working branch.

[0061] Furthermore, if Figure 5 As shown, a first resistor 81 is further provided between the base of the first transistor 71 and the overvoltage detection node 54, a second resistor 82 is connected in parallel between the base and the emitter of the first transistor 71, and a common end of the second resistor 82 and the emitter of the first transistor 71 is grounded.

[0062] In a specific implementation, a threshold voltage is set by the first resistor 81 and the second resistor 82. When the voltage of the overvoltage detection node 54 is greater than the threshold voltage of the overvoltage protection circuit 41, the overvoltage detection node 54 is connected to the base of the first transistor 71, and the collector of the first transistor 71 is connected to the gate of the MOS tube 60. At this time, the MOS tube 60 is turned off, the working branch is disconnected, and the first transistor 71 releases the short-circuit voltage to the ground loop to prevent voltage backflow from damaging the speaker drive module 20, or to prevent excessive voltage from damaging other devices on the working branch.

[0063] The threshold voltage can be set by the first resistor 81 and the second resistor 82, and different threshold voltages can be set according to the specific circuit environment of the speaker 30. Specifically, according to the circuit environment of the speaker 30, for example, if the circuit of the speaker 30 is close to a 12V power supply and there is a risk of short-circuiting with the power supply, the threshold voltage can be set to 12V by the first resistor 81 and the second resistor 82. When the voltage of the overvoltage detection node 54 is detected to be greater than 12V, the overvoltage detection node 54 is connected to the base of the first transistor 71, and the collector of the first transistor 71 is connected to the gate of the MOS tube 60, so the MOS tube 60 is immediately turned off to prevent excessive voltage from damaging the speaker drive module 20 or other devices on the working branch line, so as to effectively prevent the potential damage of the power supply overvoltage to the circuit system. By preventing overvoltage and voltage backflow, premature aging or damage of the equipment can be avoided, thereby extending the service life of the equipment. At the same time, since overvoltage and voltage backflow are common causes of equipment damage, by detecting overvoltage at the overvoltage detection node 54 and immediately shutting down the MOS tube 60, the risk of equipment damage can be reduced, the frequency of repairing and replacing equipment can be reduced, thereby reducing maintenance costs.

[0064] Based on the above embodiment, when the overvoltage detection node 54 is connected to the base of the first transistor 71, the collector of the first transistor 71 is connected to the gate of the MOS tube 60; in order to effectively cut off the circuit quickly when an overvoltage condition is detected and prevent the high voltage from flowing back from the speaker 30 to the speaker driving module 20, the MOS tube 60 is described in detail through the following embodiment.

[0065] In some embodiments, the MOS tube 60 includes an NMOS tube, a drain of the NMOS tube is connected to the speaker driving module 20 , and a source of the NMOS tube is connected to the speaker 30 .

[0066] In specific implementation, when the voltage of the overvoltage detection node 54 is greater than the threshold voltage of the overvoltage protection circuit 41 , the NMOS tube is turned off to prevent voltage backflow from the speaker 30 to the speaker driving module 20 to damage the speaker driving module 20 .

[0067] Among them, the MOS tube 60 can also be a PMOS tube. In this case, the drain of the PMOS tube is connected to the speaker 30, and the source of the PMOS tube is connected to the speaker driving module 20. When the voltage of the overvoltage detection node 54 is greater than the threshold voltage of the overvoltage protection circuit 41, the PMOS tube is turned off to prevent the voltage from being reversed from the speaker 30 to the speaker driving module 20 to damage the speaker driving module 20.

[0068] By turning off the NMOS tube when the voltage at the overvoltage detection node 54 is greater than the threshold voltage of the overvoltage protection circuit 41, the circuit can be quickly cut off when an overvoltage condition is detected, preventing the high voltage from flowing back from the speaker 30 to the speaker driver module 20. This rapid cut-off action protects the speaker driver module 20 from damage and prolongs the service life of the device.

[0069] Based on the above embodiment, two working branches are connected between the speaker driving module 20 and the speaker 30, and a switch module 40 is provided on each of the working branches; when the switch module 40 is in the off state, the MCU 10 supplies power to the diagnostic power supply node 51, and the MCU 10 is connected to the diagnostic node 52; in order to achieve precise control of the speaker driving signal, the switch module 40 is described in detail through the following embodiments.

[0070] In some embodiments, Figure 6 As shown, the switch module 40 includes a switch circuit 42 and a MOS tube 60, and the MCU 10 is connected to the gate of the MOS tube 60 through the switch circuit 42 (in the embodiment of the present application, the VP_SPK OUTCTL pin of the MCU 10 is connected to the switch circuit 42);

[0071] When the MCU 10 inputs a preset level to the switch circuit 42 , the MOS transistor 60 is turned on.

[0072] In a specific implementation, when the MCU 10 inputs a preset level to the switch circuit 42 (for example, inputs a voltage of 3.3V), the switch circuit 42 outputs a control signal to control the MOS tube 60 to be turned on, and the speaker driving module 20 provides a driving signal to the speaker 30 to drive the speaker 30 to work.

[0073] The MCU 10 can accurately control the switching state of the MOS tube 60 by controlling the switch circuit 42 to control the on or off of the MOS tube 60, thereby realizing accurate control of the speaker drive signal; by controlling the MOS tube 60 through the MCU 10, efficient power management can be realized, and the MOS tube 60 is turned on only when the speaker is required to work, which helps to reduce the energy consumption of the entire system, especially in application scenarios where the speaker does not need to work continuously. Using the MOS tube 60 as a switching element can reduce the need to use mechanical switches or other complex switching devices, thereby simplifying circuit design and reducing costs. In addition, the use of the MOS tube 60 can also reduce the space occupied on the circuit board. The switching speed of the MOS tube 60 is fast, and fast signal switching can be realized, which is particularly important for audio applications that require fast response. Compared with mechanical switches, the MOS tube 60 has higher reliability and longer life. In addition, the MOS tube 60 can provide more stable performance and reduce signal interruptions caused by problems such as poor contact.

[0074] Furthermore, if Figure 7 As shown, the switch circuit 42 includes a second transistor 72 and a third transistor 73, and the collector of the second transistor 72 is connected to the base of the third transistor 73 (in the embodiment of the present application, the second transistor 72 is an NPN transistor, and the third transistor 73 is a PNP transistor);

[0075] The base of the second transistor 72 is connected to the MCU10, the emitter of the third transistor 73 is connected to the MCU10, and the collector of the third transistor 73 is connected to the gate of the MOS transistor 60 (in the embodiment of the present application, the VP_SPK OUT CTL pin of the MCU10 is connected to the base of the second transistor 72, and the MIC_PWR pin of the MCU10 is connected to the emitter of the third transistor 73);

[0076] When the MCU 10 inputs a preset level to the base of the second transistor 72 , the collector of the second transistor 72 is connected to the base of the third transistor 73 , and the collector of the third transistor 73 is connected to the gate of the MOS transistor 60 .

[0077] In specific implementation, when the MCU10 inputs a preset level to the base of the second transistor 72 (for example, inputs a voltage of 3.3V), the second transistor 72 is in an on state, the collector of the second transistor 72 is connected to the base of the third transistor 73, the collector of the third transistor 73 is connected to the gate of the MOS tube 60, and the control signal output from the collector of the third transistor 73 controls the MOS tube 60 to be turned on, and the speaker driving module 20 provides a driving signal to the speaker 30 to drive the speaker 30 to work.

[0078] Based on the above embodiment, when the switch module 40 is in the off state, the MCU10 supplies power to the diagnostic power supply node 51, and the MCU10 is connected to the diagnostic node 52; in order to prevent the current in the working branch line from flowing to the MCU10 and causing damage to the MCU10, the MCU10 and the diagnostic power supply node 51 are described in detail through the following embodiments.

[0079] In some embodiments, Figure 8 As shown, a unidirectional diode 90 is provided between the MCU10 and the diagnostic power supply node 51, the MCU10 is connected to the anode of the unidirectional diode 90, and the diagnostic power supply node 51 is connected to the cathode of the unidirectional diode 90 (in the embodiment of the present application, the VP_SPK_DET_EN pin of the MCU10 is connected to the anode of the unidirectional diode 90).

[0080] In specific implementation, when MCU10 supplies power to the diagnostic power supply node 51, current flows from the anode of the unidirectional diode 90 to the cathode of the unidirectional diode 90. When the speaker 30 works normally, MCU10 stops supplying power to the diagnostic power supply node 51. At this time, the unidirectional diode 90 can prevent the current in the working branch from flowing to the MCU10 and causing damage to the MCU10. The unidirectional diode 90 can be a Schottky diode, whose lower forward voltage drop and fast switching speed can reduce power consumption and improve efficiency; a TVS diode (transient voltage suppression diode) can also be used to prevent high energy spikes from damaging the MCU10.

[0081] The utility model also provides a vehicle, which includes a speaker diagnosis protection circuit. The vehicle has the beneficial effects of the corresponding circuit embodiment, which will not be described in detail here.

[0082] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present disclosure (including the claims) is limited to these examples. Under the concept of the present invention, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the present invention as described above, which are not provided in detail for the sake of simplicity.

[0083] The embodiments of the present invention are intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A speaker diagnostic protection circuit, characterized in that: It includes an MCU, a speaker driving module and a speaker, wherein two working branches are connected between the speaker driving module and the speaker, and each of the working branches is provided with a switch module, wherein one of the working branches is provided with a diagnostic power supply node, and the other working branch is provided with a diagnostic node, and the diagnostic power supply node and the diagnostic node are both located between the switch module and the speaker; Wherein, the diagnostic power supply node and the diagnostic node are respectively connected to the MCU; When the switch module is in the off state, the MCU supplies power to the diagnosis power supply node, and the MCU is connected to the diagnosis node.

2. The speaker diagnosis protection circuit according to claim 1, characterized in that: The switch module includes an overvoltage protection circuit and a MOS tube. The working branch line is also provided with an overvoltage detection node, the overvoltage detection node is located between the MOS tube and the speaker, and the overvoltage detection node is connected to the gate of the MOS tube through the overvoltage protection circuit; When the overvoltage detection node is connected to the overvoltage protection circuit, the MOS tube is turned off.

3. The speaker diagnosis protection circuit according to claim 2, characterized in that: The overvoltage protection circuit comprises a first transistor, wherein the base of the first transistor is connected to the overvoltage detection node, and the collector is connected to the gate of the MOS transistor; When the overvoltage detection node is connected to the base of the first transistor, the collector of the first transistor is connected to the gate of the MOS transistor.

4. The speaker diagnosis protection circuit according to claim 1, characterized in that: The switch module includes a switch circuit and a MOS tube, and the MCU is connected to the gate of the MOS tube through the switch circuit; When the MCU inputs a preset level to the switch circuit, the MOS tube is turned on.

5. The speaker diagnosis protection circuit according to claim 4, characterized in that: The switch circuit comprises a second triode and a third triode, wherein the collector of the second triode is connected to the base of the third triode; Wherein, the base of the second triode is connected to the MCU, the emitter of the third triode is connected to the MCU, and the collector of the third triode is connected to the gate of the MOS tube; When the MCU inputs a preset level to the base of the second transistor, the collector of the second transistor is connected to the base of the third transistor, and the collector of the third transistor is connected to the gate of the MOS transistor.

6. The speaker diagnosis protection circuit according to claim 1, characterized in that: Another diagnostic node is also provided on the working branch line where the diagnostic power supply node is located, and the other diagnostic node is located between the switch module and the speaker and is connected to the MCU; When the switch module is in the off state, the MCU supplies power to the diagnostic power supply node, and the MCU is connected to all diagnostic nodes.

7. The speaker diagnosis protection circuit according to claim 1, characterized in that: A unidirectional diode is provided between the MCU and the diagnosis power supply node, the MCU is connected to the anode of the unidirectional diode, and the diagnosis power supply node is connected to the cathode of the unidirectional diode.

8. The speaker diagnosis protection circuit according to claim 2, characterized in that: The MOS tube includes an NMOS tube, a drain of the NMOS tube is connected to the speaker driving module, and a source of the NMOS tube is connected to the speaker.

9. The speaker diagnosis protection circuit according to claim 3, characterized in that: A first resistor is further provided between the base of the first transistor and the overvoltage detection node, a second resistor is connected in parallel between the base and the emitter of the first transistor, and a common end of the second resistor and the emitter of the first transistor is grounded.

10. A vehicle, characterized in that: The invention comprises a loudspeaker diagnosis and protection circuit as claimed in any one of claims 1 to 9.

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