Sound wake-up circuit suitable for high-voltage vehicle-mounted system and sound equipment

Abstract

The utility model discloses a sound wake-up circuit suitable for a high-voltage vehicle-mounted system and sound equipment. The sound wake-up circuit comprises a wake-up signal input terminal, a voltage judgment module and a wake-up signal output terminal. The voltage judgment module accesses a wake-up signal from the high-voltage vehicle-mounted system through the wake-up signal input terminal; the voltage judgment module comprises a triode and a voltage stabilizing diode D3, an emitting electrode of the triode is connected with the wake-up signal input terminal, a base electrode of the triode is connected with the voltage stabilizing diode D3, and a collector electrode of the triode is connected to the wake-up signal output terminal; and the wake-up signal output terminal is connected with a power supply circuit of the sound equipment. According to the utility model, a CAN chip with a wake-up function does not need to be used, and the wake-up of sound equipment of a 24V and other high-voltage vehicle-mounted system (such as a truck system) is realized in a low-cost manner, especially the wake-up of a pedestrian warning indicator is realized.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the field of vehicle-mounted audio equipment, and relates to a sound equipment of high-voltage vehicle-mounted system and a sound awakening circuit thereof, in particular to a sound equipment of 24V vehicle-mounted system, such as a vehicle pedestrian warning device of large transport vehicles such as trucks. BACKGROUND

[0002] With the continuous development of new energy vehicles, some large transport vehicles such as trucks also begin to enter the new energy driving mode, and the driving force is provided to the vehicle by replacing the traditional internal combustion engine with a battery. Unlike internal combustion engines, the engine of an electric vehicle hardly makes mechanical sound. This means that new energy vehicles are almost silent when driving at low speed, which makes it difficult for pedestrians (especially visually impaired pedestrians) to be aware when a new energy vehicle approaches. Therefore, according to safety regulations, trucks using new energy driving mode must also be equipped with a vehicle pedestrian warning device (AVAS) to remind pedestrians that there is a vehicle, especially during low-speed driving.

[0003] The power supply voltage of the vehicle-mounted system of the truck is relatively high, generally with a 24V system as the main one. The driving and control module of the pedestrian warning device of a conventional small vehicle (such as a passenger car) cannot be directly applied to the 24V vehicle-mounted system. The vehicle-mounted audio equipment such as AVAS of a small vehicle generally uses a CAN chip with awakening function to realize system awakening, but the working voltage of the CAN chip with awakening function is 12V, which cannot be directly compatible with 24V voltage, and the CAN chip with awakening function itself has a high cost.

[0004] The above information disclosed in the background section is only used to strengthen the understanding of the background of the present application, and therefore it can include information that does not constitute prior art known to those of ordinary skill in the art. UTILITY MODEL CONTENT

[0005] Therefore, the utility model provides a sound awakening circuit and sound equipment suitable for high-voltage vehicle-mounted system, which does not need to use a CAN chip with awakening function, and realizes the awakening of the sound equipment of a 24V high-voltage vehicle-mounted system (such as a truck system) in a low-cost manner, especially the awakening of the pedestrian warning device.

[0006] The utility model adopts the following technical solutions:

[0007] A sound awakening circuit suitable for a high-voltage vehicle-mounted system; the sound awakening circuit comprises a wakeup signal input terminal, a voltage judgment module and a wakeup signal output terminal; the voltage judgment module is connected to the wakeup signal from the high-voltage vehicle-mounted system through the wakeup signal input terminal;

[0008] The voltage judging module comprises a transistor and a voltage stabilizing diode D3, the emitter of the transistor is connected with the wake-up signal input terminal, the base of the transistor is connected with the voltage stabilizing diode D3, and the collector of the transistor is connected with the wake-up signal output terminal.

[0009] The wake-up signal output terminal is configured to be connected with the power circuit of the audio equipment of the high-voltage vehicle-mounted system.

[0010] In a preferred embodiment, the emitter of the transistor is connected with a resistor R3, the base of the transistor is connected with the first end of the voltage stabilizing diode D3 through a resistor R4, and the second end of the voltage stabilizing diode D3 is grounded; the voltage judging module further comprises a capacitor C4, the first end of the capacitor C4 is connected with the resistor R3, and the second end of the capacitor C4 is grounded; the connection point of the resistor D3 and the capacitor C4 is connected with the connection point of the resistor R4 and the first end of the voltage stabilizing diode through a wire.

[0011] In a preferred embodiment, the audio wake-up circuit further comprises an anti-reverse module and a voltage division and filtering module, and the anti-reverse module, the voltage division and filtering module and the voltage judging module are sequentially arranged.

[0012] In a more preferred embodiment, the anti-reverse module comprises an anti-reverse diode D1, and the anti-reverse diode is connected between the wake-up signal input terminal and the emitter of the transistor.

[0013] In a further preferred embodiment, the voltage division and filtering module comprises a resistor R1, a resistor R2 and a capacitor, the resistor R1 is connected in series between the anti-reverse diode D1 and the emitter of the transistor, the first end of the resistor R2 is connected with the connection point of the resistor R1 and the emitter of the transistor, the second end of the resistor R2 is grounded, and the capacitor and the resistor R2 are connected in parallel with each other.

[0014] In a further preferred embodiment, the voltage division and filtering module further comprises an inductor FB1, and the inductor FB1 is connected in series between the resistor R1 and the emitter of the transistor.

[0015] The voltage division and filtering module further comprises a transient voltage suppression diode D2, the first end of the transient voltage suppression diode D2 is connected with the connection point of the inductor FB1 and the emitter of the transistor, and the second end of the transient voltage suppression diode D2 is grounded.

[0016] The capacitor comprises a capacitor C1, a capacitor C2 and a capacitor C3, a first end of the capacitor C1 is connected to a connection point of the wake-up signal input terminal and the anti-reverse diode D1, a first end of the capacitor C2 is connected to a connection point of the resistor R1 and the inductor FB1, a first end of the capacitor C3 is connected to a connection point of the inductor FB1 and the emitter of the triode, the capacitor C1, the capacitor C2, the resistor R2, the transient voltage suppression diode D2 and the capacitor C3 are sequentially arranged, and second ends of the capacitor C1, the capacitor C2 and the capacitor C3 are grounded.

[0017] In a preferred embodiment, the sound awakening circuit further comprises a voltage protection module, and the collector of the triode is connected to the wake-up signal output terminal through the voltage protection module.

[0018] The voltage protection module comprises a voltage stabilizing diode D4, a first end of the voltage stabilizing diode D4 is connected to a connection point of the collector of the triode and the wake-up signal output terminal, and a second end of the voltage stabilizing diode D4 is grounded.

[0019] In a more preferred embodiment, the voltage protection module further comprises a resistor R5, a resistor R6 and a capacitor C5, the collector of the triode is connected to the wake-up signal output terminal through the resistor R5, a first end of the resistor R6 is connected to a connection point of the resistor R5 and the wake-up signal output terminal, a second end of the resistor R6 is grounded, and the capacitor C5 is connected in parallel to the resistor R6.

[0020] The voltage protection module further comprises a capacitor C6, a first end of the capacitor C6 is connected to the wake-up signal output terminal, and a second end of the capacitor C6 is grounded.

[0021] The utility model discloses still adopt following technical scheme:

[0022] A sound equipment suitable for a high-voltage vehicle-mounted system, comprising a vehicle-mounted sound generating device, a sound awakening circuit and a power supply circuit for supplying power to the vehicle-mounted sound generating device; the sound awakening circuit is the sound awakening circuit as described above.

[0023] In a preferred embodiment, the vehicle-mounted system is a 24V vehicle-mounted system, when the level of the signal input into the wake-up signal input terminal is higher than a set value, the wake-up signal output terminal outputs a high-level signal, and when the level of the signal input into the wake-up signal input terminal is lower than the set value, the wake-up signal output terminal outputs a low-level signal.

[0024] In a preferred embodiment, the power supply circuit comprises a power supply chip, and the wake-up signal output terminal is connected to a wake pin of the power supply chip.

[0025] In a preferred embodiment, the vehicle-mounted sound device comprises a pedestrian warning device mounted on a truck, the vehicle-mounted system is a vehicle-mounted system of the truck, and the power supply chip supplies power for a power amplifier of the pedestrian warning device.

[0026] The utility model discloses the above scheme has the following advantages:

[0027] The utility model discloses a sound equipment and its wake -up circuit, set up the sound wake -up circuit between the power supply circuit of vehicle-mounted system and vehicle-mounted sound device, judge whether the level of the signal of wake -up signal input terminal access meets the set wake -up condition through the voltage judgment module of sound wake -up circuit, when meeting the set wake -up condition, output high level wake -up signal through wake -up signal output terminal, wake up power supply circuit to supply power for vehicle-mounted sound device, can be compatible with the high voltage vehicle-mounted system of 24V or more, be suitable for the truck of high voltage vehicle-mounted system of large -scale transport vehicle use, can be used for the wake -up of pedestrian warning device, the loudspeaker of entertainment or remote conversation of large -scale transport vehicle, etc. BRIEF DESCRIPTION OF DRAWINGS

[0028] In order to more clearly illustrate the technical scheme of the utility model, the following will be to the embodiment description needed to use the drawing briefly introduced, obviously, the following description in the drawing is only some embodiments of the utility model, for those skilled in the art, under the premise of not paying the creative labor, can also obtain other drawings according to these drawings.

[0029] Figure 1 It is a module diagram of a sound equipment according to an embodiment of the utility model.

[0030] Figure 2 It is a module diagram of a sound wake -up circuit according to an embodiment of the utility model.

[0031] Figure 3 It is a circuit diagram of a sound wake -up circuit according to an embodiment of the utility model.

[0032] Figure 4 It is a wake -up flow chart of a sound equipment according to an embodiment of the utility model.

[0033] In the above drawings,

[0034] 1, vehicle-mounted system;11, ECU;2, sound wake -up circuit;3, power supply circuit;4, power amplifier;5, loudspeaker;

[0035] 21, wake -up signal input terminal;22, anti -reversal module;23, voltage division filter module;24, voltage judgment module;25, voltage protection module;26, wake -up signal output terminal. DETAILED DESCRIPTION

[0036] The following describes in detail preferred embodiments of the present invention in conjunction with the accompanying drawings to make the advantages and features of the present invention more easily understood by those skilled in the art. It should be noted that the description of these embodiments is intended to facilitate understanding of the present invention and does not constitute a limitation of the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0037] The following embodiments relate to audio equipment suitable for high-voltage vehicle-mounted systems, and more specifically, to audio wake-up circuits for such systems. These high-voltage vehicle-mounted systems operate at voltages above 24V, typically 24V vehicle-mounted systems; in other embodiments, 48V vehicle-mounted systems can be used. These vehicle-mounted systems are typically used in large battery-powered transport vehicles, such as new energy trucks.

[0038] Reference Figure 1 As shown, the audio device includes an on-board sound device, an audio wake-up circuit 2, and a power supply circuit 3 for powering the on-board sound device. An "on-board sound device" refers to a device installed on a vehicle that can achieve electro-acoustic conversion and can broadcast sound inside or outside the vehicle. In this embodiment, the audio device is typically a pedestrian alert system (AVAS) for a new energy truck. The pedestrian alert system is installed on the truck and broadcasts a warning sound outside the vehicle to alert pedestrians to the vehicle's presence. The pedestrian alert system includes a speaker 5 that can achieve electro-acoustic conversion. In other embodiments, the audio device may be an in-vehicle audio system that broadcasts sound into the vehicle for entertainment or remote calling functions. The in-vehicle audio system may include door panel speakers, headrest speakers, ceiling speakers, etc., and the sound frequency range covers bass to treble. The power supply circuit 3 may include a power chip, such as an LDO or DC-DC chip. The power supply circuit 3 is electrically connected to the power amplifier 4 and can power the power amplifier 4. The power amplifier 4 is electrically connected to the speaker 5, and the power amplifier 4 drives the speaker 5 to produce sound.

[0039] Combine Figure 2 and Figure 3As shown, the sound awakening circuit 2 comprises a wake-up signal input terminal 21, a voltage judgment module 24 and a wake-up signal output terminal 26. The voltage judgment module 24 is connected to the wake-up signal from the high-voltage vehicle system 1 through the wake-up signal input terminal 21. In the present embodiment, the wake-up signal input terminal 21 is connected to the car audio system of the truck; for example, the wake-up signal input terminal 21 is electrically connected to the electronic controller ECU 11 of the truck. The wake-up signal output terminal 26 is connected to the power supply circuit 3 of the vehicle sound unit, specifically to the wake pin of the power supply chip. The voltage judgment module 24 comprises a transistor Q1 and a voltage stabilizing diode D3, the emitter of the transistor Q1 is connected to the wake-up signal input terminal 21, the base of the transistor Q1 is connected to the voltage stabilizing diode D3, and the collector of the transistor Q1 is connected to the wake-up signal output terminal 26. The vehicle system 1 is a 24V vehicle system, when the level of the signal connected to the wake-up signal input terminal 21 is higher than a set value, the wake-up signal output terminal 26 outputs a high-level signal, and when the level of the signal connected to the wake-up signal input terminal 21 is lower than a set value, the wake-up signal output terminal 26 outputs a low-level signal.

[0040] The emitter of the transistor Q1 is connected to a resistor R3, the base of the transistor Q1 is connected to the first end of the voltage stabilizing diode D3 through a resistor R4, and the second end of the voltage stabilizing diode D3 is grounded. The voltage judgment module 24 further comprises a capacitor C4, the first end of the capacitor C4 is connected to the resistor R3, and the second end of the capacitor C4 is grounded; the connection point of the resistor D3 and the capacitor C4 is connected to the connection point of the resistor R4 and the first end of the voltage stabilizing diode through a wire. In the present embodiment, the transistor Q1 is a PNP transistor, the voltage stabilizing diode D3 is used as a clamping tube, and the combination of the PNP tube and the clamping tube realizes the closing of the wake-up below a set voltage (for example, 4V) and the opening of the wake-up above another set voltage (for example, 7V), and finally the voltage divided with the clamping tube output voltage is used to control the back-end system. The resistor R3 and the resistor R4 are used to drive the transistor Q1, and the capacitor C4 is used for filtering to prevent the occurrence of pulse spikes.

[0041] The sound awakening circuit 2 further comprises an anti-reverse module 22 and a voltage dividing and filtering module 23, and the anti-reverse module 22, the voltage dividing and filtering module 23 and the voltage judgment module 24 are sequentially arranged. The anti-reverse module 22 comprises an anti-reverse diode D1 connected between the wake-up signal input terminal 21 and the emitter of the transistor Q1. The anti-reverse diode prevents reverse voltage and protects the circuit. The voltage dividing and filtering module 23 comprises a resistor R1, a resistor R2 and a capacitor, the resistor R1 is connected in series between the anti-reverse diode D1 and the emitter of the transistor Q1, the first end of the resistor R2 is connected to the connection point of the resistor R1 and the emitter of the transistor Q1, the second end of the resistor R2 is grounded, and the capacitor and the resistor R2 are connected in parallel to each other.

[0042] The voltage division filter module 23 further comprises an inductor FB1 connected in series between the resistor R1 and the emitter of the transistor Q1. The voltage division filter module 23 further comprises a transient voltage suppression diode D2, a first end of the transient voltage suppression diode D2 being connected to the connection point of the inductor FB1 and the emitter of the transistor Q1, and a second end of the transient voltage suppression diode D2 being grounded. The capacitors comprise a capacitor C1, a capacitor C2 and a capacitor C3, a first end of the capacitor C1 being connected to the connection point of the wake-up signal input terminal 21 and the anti-reverse diode D1, a first end of the capacitor C2 being connected to the connection point of the resistor R1 and the inductor FB1, and a first end of the capacitor C3 being connected to the connection point of the inductor FB1 and the emitter of the transistor Q1, the capacitor C1, the capacitor C2, the resistor R2, the transient voltage suppression diode D2 and the capacitor C3 being arranged in sequence, and second ends of the capacitor C1, the capacitor C2 and the capacitor C3 being grounded. Among them, the resistor R1, the resistor R2 and the capacitor C1 constitute a voltage division filter circuit. The transient voltage suppression diode D2 is used for suppressing transient voltage and protecting the subsequent circuit. The inductor FB1, the capacitor C2 and the capacitor C3 play a π-type filtering role.

[0043] The sound wake-up circuit 2 further comprises a voltage protection module 25, the collector of the transistor Q1 being connected to the wake-up signal output terminal 26 through the voltage protection module 25. The voltage protection module 25 comprises a zener diode D4, a first end of the zener diode D4 being connected to the connection point of the collector of the transistor Q1 and the wake-up signal output terminal 26, and a second end of the zener diode D4 being grounded. The zener diode D4 plays a clamping role and can be clamped to a fixed voltage at most.

[0044] The voltage protection module 25 further comprises a resistor R5, a resistor R6 and a capacitor C5, the collector of the transistor Q1 being connected to the wake-up signal output terminal 26 through the resistor R5, a first end of the resistor R6 being connected to the connection point of the resistor R5 and the wake-up signal output terminal 26, a second end of the resistor R6 being grounded, and the capacitor C5 being connected in parallel to the resistor R6. The resistor R5 and the resistor R6 play a voltage division role, and the capacitor C5 plays a filtering and energy storage role. The voltage protection module 25 further comprises a capacitor C6, a first end of the capacitor C6 being connected to the wake-up signal output terminal 26, and a second end of the capacitor C6 being grounded, the capacitor C6 further performing filtering processing.

[0045] As Figure 3As shown, the wake-up signal input terminal 21, the anti-reverse diode D1, the resistor R1, the inductor FB1, and the emitter of the triode Q1 are connected in series, the collector of the triode Q1, the resistor R5, and the wake-up signal output terminal 26 are connected in series, and the capacitor C1 is connected between the wake-up signal input terminal 21 and the ground. One end of the resistor R2 is connected to the connection point of the resistor R1 and the inductor FB1, and the other end is grounded; the capacitor C2 is connected in parallel to the resistor R2. One end of the diode D2 is connected to the connection point of the inductor FB1 and the emitter of the triode Q1, and the other end is grounded; the capacitor C3 is connected in parallel to the diode D2 and is located between the diode D2 and the emitter of the triode Q1. The resistor R3 and the capacitor C4 are connected in series to form a first branch connected to the ground, the resistor R4 and the diode D3 are connected in series to form a second branch connected to the ground, and the first branch and the second branch are both located at the rear side of the capacitor C3. The middle point (the connection point of the resistor R3 and the capacitor C4) of the first branch is connected to the middle point (the connection point of the resistor R4 and the diode D3) of the second branch through a wire. The capacitor C5 is connected between the collector of the triode Q1 and the ground. The resistor R5, the resistor R6, the diode D4, and the capacitor C6 are sequentially located at the rear side of the capacitor C5.

[0046] In this embodiment, the power supply voltage of the truck system is relatively high, mainly a 24V system. In order to ensure the stability of the performance of the electrical appliances of the truck system, the wake-up control voltage of the audio equipment is required to be below 4V to turn off the electronic components, greater than or equal to 7V to turn on the electronic components, and between 4V and 7V to be a control buffer zone.

[0047] The external input wake-up signal is input into the anti-reverse module 22 to prevent reverse voltage and protect the circuit, then passes through the voltage division and filtering module 23 to provide a stable voltage for the rear end and eliminate interference signals, is screened by the voltage judgment module 24 composed of a PNP tube and a voltage stabilizing diode to realize the wake-up to be turned off below 4V and the wake-up to be turned on above 7V, and finally is protected by the resistor voltage protection module 25 to protect the output signal level. Generally, when a truck or other large transport vehicle is started, such as using a key to start or one-key starting the vehicle, the vehicle will send a wake-up signal to the AVAS to start the AVAS function.

[0048] Specifically, in combination with Figure 3As shown, from the start of the wake-up signal input, the reverse prevention is carried out through the reverse prevention diode D1 for protecting the circuit from reverse voltage; the input stable voltage is provided through the voltage division of the resistor R1 and the resistor R2 and the filtering circuit, the voltage division ratio is 1:0.8; then the voltage determination module 24 is passed, which is composed of the PNP tube Q1 combination and the voltage stabilizing diode D3, when the signal input voltage is higher than 7V, the tube voltage drop is formed through the emitter and the base of Q1, the voltage stabilizing diode D3 stabilizes the voltage, so that the PNP tube Q1 is in the conducting state, and the high level voltage is output; when the signal input voltage is lower than 4V, the tube voltage drop cannot be formed at this time through the emitter and the base of the PNP tube, Q1 is in the non-conducting state; the output voltage is divided and then protected by the voltage stabilizing diode D4, and finally the signal is output.

[0049] In combination Figure 4 As shown, when the wake-up signal input voltage is input, the voltage is divided, and it is determined whether the divided voltage is greater than 5.2V; if the divided voltage is less than 5.2V, the signal output is low at this time, if the divided voltage is greater than 5.2V, the signal output is high at this time, and then the voltage division protection is passed to finally output the high level signal. In this embodiment, the design requirement is: greater than 7V input high level, less than 4V input low level; a voltage value between 4-7V also needs to be combined with the WAKE pin voltage of the power supply chip behind, so 5.2V is selected as the judgment comparison threshold. In other embodiments, the judgment comparison threshold is not necessarily this value, according to different design requirements, the value can be changed by modifying the resistance value.

[0050] The sound equipment of the embodiment is provided with the sound wake-up circuit 2 between the power supply circuit 3 of the vehicle-mounted system and the vehicle-mounted sound device, the voltage determination module 24 of the sound wake-up circuit 2 determines whether the level of the signal input into the wake-up signal input terminal 21 meets the set wake-up condition, when the set wake-up condition is met, the high level wake-up signal is output through the wake-up signal output terminal 26, the power supply circuit 3 is woken up to supply power for the vehicle-mounted sound device, the vehicle-mounted system with high voltage above 24V can be compatible, it is suitable for large transport vehicles such as trucks with high voltage of the vehicle-mounted system, and can be used for the wake-up of the sound equipment such as the pedestrian warning device, the speaker for entertainment or remote communication of the large transport vehicles; without using the CAN chip with wake-up function, the wake-up of the vehicle-mounted sound equipment is realized at a lower cost.

[0051] As shown in the specification and claims, the terms "comprise" and "include" only indicate the inclusion of the steps and elements explicitly identified, and these steps and elements do not constitute an exclusive list, and the method or device can also include other steps or elements.

[0052] It can be further understood that "multiple" in the disclosure means two or more, and other quantifiers are similar.

[0053] It is further to be understood that the terms "first", "second", etc. are used to describe various information, but such information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other, and do not indicate a particular order or importance. In fact, the expressions "first", "second", etc. can be used interchangeably. For example, the first information can also be referred to as the second information, and similarly, the second information can also be referred to as the first information without departing from the scope of the present disclosure.

[0054] The above embodiments are only for illustrating the technical concept and characteristics of the present application, and are a preferred embodiment, the purpose of which is to enable those skilled in the art to understand the content of the present application and to implement it, and cannot limit the protection scope of the present application.

Claims

1. An audible wake-up circuit adapted for a high voltage on-board system, characterized in that The sound awakening circuit comprises an awakening signal input terminal, a voltage judging module and an awakening signal output terminal; the voltage judging module is connected to the awakening signal from the high-voltage vehicle system through the awakening signal input terminal; The voltage judging module comprises a transistor and a stabilizing diode D3, the emitter of the transistor is connected to the awakening signal input terminal, the base of the transistor is connected to the stabilizing diode D3, and the collector of the transistor is connected to the awakening signal output terminal; The awakening signal output terminal is configured to be connected to the power circuit of the sound equipment of the high-voltage vehicle system.

2. The acoustic wake-up circuit of claim 1, wherein, The emitter of the transistor is connected to a resistor R3, the base of the transistor is connected to the first end of the stabilizing diode D3 through a resistor R4, and the second end of the stabilizing diode D3 is grounded; the voltage judging module further comprises a capacitor C4, the first end of the capacitor C4 is connected to the resistor R3, and the second end of the capacitor C4 is grounded; the connection point of the resistor D3 and the capacitor C4 is connected to the connection point of the resistor R4 and the first end of the stabilizing diode through a wire.

3. The acoustic wake-up circuit of claim 1, wherein, The sound awakening circuit further comprises an anti-reverse module and a voltage division and filtering module, the anti-reverse module, the voltage division and filtering module and the voltage judging module are sequentially arranged.

4. The acoustic wake-up circuit of claim 3, wherein, The anti-reverse module comprises an anti-reverse diode D1, which is connected between the awakening signal input terminal and the emitter of the transistor.

5. The acoustic wake-up circuit of claim 4, wherein, The voltage division and filtering module comprises a resistor R1, a resistor R2 and a capacitor, the resistor R1 is connected in series between the anti-reverse diode D1 and the emitter of the transistor, the first end of the resistor R2 is connected to the connection point of the resistor R1 and the emitter of the transistor, the second end of the resistor R2 is grounded, and the capacitor and the resistor R2 are connected in parallel with each other.

6. The acoustic wake-up circuit of claim 5, wherein, The voltage division and filtering module further comprises an inductor FB1, which is connected in series between the resistor R1 and the emitter of the transistor. The voltage division and filtering module further comprises a transient voltage suppression diode D2, the first end of the transient voltage suppression diode D2 is connected to the connection point of the inductor FB1 and the emitter of the transistor, and the second end of the transient voltage suppression diode D2 is grounded. The capacitor comprises a capacitor C1, a capacitor C2 and a capacitor C3, the first end of the capacitor C1 is connected to the connection point of the awakening signal input terminal and the anti-reverse diode D1, the first end of the capacitor C2 is connected to the connection point of the resistor R1 and the inductor FB1, and the first end of the capacitor C3 is connected to the connection point of the inductor FB1 and the emitter of the transistor; the capacitor C1, the capacitor C2, the resistor R2, the transient voltage suppression diode D2 and the capacitor C3 are sequentially arranged, and the second ends of the capacitor C1, the capacitor C2 and the capacitor C3 are grounded.

7. The acoustic wake-up circuit of any one of claims 1 to 6, wherein, The sound awakening circuit further comprises a voltage protection module, the collector of the transistor is connected to the awakening signal output terminal through the voltage protection module; The voltage protection module comprises a stabilizing diode D4, the first end of the stabilizing diode D4 is connected to the connection point of the collector of the transistor and the awakening signal output terminal, and the second end of the stabilizing diode D4 is grounded.

8. The acoustic wake-up circuit of claim 7, wherein, The voltage protection module further comprises a resistor R5, a resistor R6 and a capacitor C5, a collector of the triode is connected to the wake-up signal output terminal through the resistor R5, a first end of the resistor R6 is connected to a connection point of the resistor R5 and the wake-up signal output terminal, a second end of the resistor R6 is grounded, and the capacitor C5 is connected in parallel to the resistor R6; The voltage protection module further comprises a capacitor C6, a first end of the capacitor C6 is connected to the wake-up signal output terminal, and a second end of the capacitor C6 is grounded.

9. A sound device suitable for a high-voltage vehicle system, comprising a vehicle sound generating device, a sound wake-up circuit and a power supply circuit for supplying power to the vehicle sound generating device; characterized in that, The sound wake-up circuit is the sound wake-up circuit according to any one of claims 1 to 8.

10. The acoustic device of claim 9, wherein, The vehicle-mounted system is a 24V vehicle-mounted system; the power supply circuit comprises a power supply chip, the wake-up signal output terminal is connected to a wake pin of the power supply chip; and the vehicle-mounted sound device comprises a pedestrian warning device installed on a truck, the vehicle-mounted system is a vehicle-mounted system of the truck, and the power supply chip supplies power for a power amplifier of the pedestrian warning device.

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