Sound equipment suitable for high-voltage vehicle-mounted system
By designing a wake-up circuit in a high-voltage vehicle-mounted system, using the voltage judgment module to judge the wake-up signal, and outputting a high-level signal to wake-up power supply circuit, it solves the problem that pedestrians cannot detect when driving silently in new energy trucks, and realizes the wake-up of audio equipment under low-cost and high-voltage systems.
Patent Information
- Application Number
- CN202411767444.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-04
- Publication Date
- 2025-02-28
AI Technical Summary
Large transport vehicles such as new energy trucks drive silently when driving at low speeds, which makes it difficult for pedestrians, especially pedestrians with vision impairment, to detect the existence of vehicles. They need to be equipped with vehicle pedestrian warning (AVAS). However, the 12V system of existing small vehicles cannot be directly compatible with 24V vehicle-mounted systems, and the CAN chip with wake-up function is relatively expensive.
Design an audio device suitable for a high-voltage vehicle-mounted system. By setting a wake-up circuit between the vehicle-mounted system and the power supply circuit, using the voltage judgment module to determine the level of the wake-up signal, output a high-level signal to wake-up the power supply circuit, and realize the wake-up of the audio device of a high-voltage vehicle-mounted system above 24V, avoiding the use of a CAN chip with a wake-up function.
It realizes low-cost wake-up pedestrian warning and other audio equipment in high-voltage vehicle-mounted systems such as 24V. It is suitable for large transport vehicles, reduces costs and is compatible with high-voltage systems.
Smart Images
Figure CN119527198A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the field of vehicle audio equipment, and relates to an audio device of a high-voltage vehicle system, in particular to an audio device of a 24V vehicle system, such as a vehicle pedestrian warning device of a large transport vehicle such as a truck. Background Art
[0002] With the continuous development of new energy vehicles, some large transport vehicles such as trucks have also begun to enter the new energy drive mode, with batteries replacing traditional internal combustion engines to provide driving force for the vehicle. Unlike internal combustion engines, the engine of electric vehicles makes almost no mechanical sound. This means that when driving at low speeds, new energy vehicles are almost silent, making it difficult for pedestrians (especially those with visual impairments) to notice when new energy vehicles are approaching. Therefore, in accordance with safety regulations, trucks using new energy drive modes must also be equipped with a vehicle pedestrian alert system (AVAS) to remind pedestrians of the presence of vehicles, especially when the vehicle is driving at low speeds.
[0003] The power supply voltage of the truck's onboard system is relatively high, generally based on the 24V system. The driving and control modules of the pedestrian warning device of conventional small vehicles (such as passenger cars) cannot be directly applied to the 24V onboard system. The onboard audio equipment such as AVAS of small vehicles generally use a CAN chip with a wake-up function to realize system wake-up, but the working voltage of the CAN chip with a wake-up function is 12V, which is not directly compatible with the 24V voltage, and the CAN chip with a wake-up function itself is relatively expensive.
[0004] The above information disclosed in the Background section is only for enhancement of understanding of the background of the present application and therefore it may contain information that does not constitute the prior art that is already known to a person of ordinary skill in the art. Summary of the invention
[0005] In view of this, the present invention provides an audio device suitable for a high-voltage vehicle-mounted system, which does not require the use of a CAN chip with a wake-up function, and can realize the wake-up of the audio device of a 24V or other high-voltage vehicle-mounted system (such as a truck system) in a low-cost manner, especially the wake-up of a pedestrian warning device.
[0006] The present invention adopts the following technical solution:
[0007] An audio device suitable for a high-voltage vehicle-mounted system, comprising a vehicle-mounted sound device, a wake-up circuit and a power supply circuit for powering the vehicle-mounted sound device; the 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 receives a wake-up signal from the high-voltage vehicle-mounted system through the wake-up signal input terminal;
[0008] The voltage judgment module includes a transistor and a voltage regulator diode D3, the emitter of the transistor is connected to the wake-up signal input terminal, the base of the transistor is connected to the voltage regulator diode D3, and the collector of the transistor is connected to the wake-up signal output terminal;
[0009] The wake-up signal output terminal is connected to the power supply circuit.
[0010] In a preferred embodiment, the emitter of the transistor is connected to a resistor R3, the base of the transistor is connected to the first end of the Zener diode D3 through the resistor R4, and the second end of the Zener diode D3 is grounded; the voltage judgment module also includes 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 between the resistor D3 and the capacitor C4 is connected to the connection point between the resistor R4 and the first end of the Zener diode through a wire.
[0011] In a preferred embodiment, the wake-up circuit further includes an anti-reverse module and a voltage-dividing and filtering module, and the anti-reverse module, the voltage-dividing and filtering module and the voltage judgment module are arranged in sequence.
[0012] In a more preferred embodiment, the anti-reverse module includes 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 divider filter module includes 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 between 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 to each other.
[0014] In a further preferred embodiment, the voltage-dividing filter module further includes an inductor FB1, and the inductor FB1 is connected in series between the resistor R1 and the emitter of the transistor;
[0015] The voltage dividing and filtering module further includes a transient voltage suppression diode D2, a first end of the transient voltage suppression diode D2 is connected to a connection point between the inductor FB1 and the emitter of the transistor, and a second end of the transient voltage suppression diode D2 is grounded;
[0016] The capacitor includes capacitor C1, capacitor C2 and capacitor C3. The first end of capacitor C1 is connected to the connection point of the wake-up signal input terminal and the anti-reverse diode D1, the first end of capacitor C2 is connected to the connection point of resistor R1 and inductor FB1, the first end of capacitor C3 is connected to the connection point of inductor FB1 and the emitter of the transistor, capacitor C1, capacitor C2, resistor R2, transient voltage suppression diode D2 and capacitor C3 are arranged in sequence, and the second ends of capacitor C1, capacitor C2 and capacitor C3 are grounded.
[0017] In a preferred embodiment, the wake-up circuit further includes a voltage protection module, and the collector of the transistor is connected to the wake-up signal output terminal through the voltage protection module;
[0018] The voltage protection module includes a voltage stabilizing diode D4 , a first end of the voltage stabilizing diode D4 is connected to a connection point between the collector of the transistor 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 includes a resistor R5, a resistor R6 and a capacitor C5, the collector of the transistor is connected to the wake-up signal output terminal through the resistor R5, the first end of the resistor R6 is connected to the connection point between the resistor R5 and the wake-up signal output terminal, the 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 includes 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] In a preferred embodiment, the vehicle-mounted system is a 24V vehicle-mounted system. When the level of the signal connected to the wake-up signal input terminal is higher than the set value, the wake-up signal output terminal outputs a high-level signal. When the level of the signal connected to the wake-up signal input terminal is lower than the set value, the wake-up signal output terminal outputs a low-level signal.
[0022] In a preferred embodiment, the power circuit includes a power chip, and the wake-up signal output terminal is connected to a wake pin of the power chip.
[0023] In a preferred embodiment, the vehicle-mounted sound generating device comprises a pedestrian warning device installed on a truck, the vehicle-mounted system is the vehicle-mounted system of the truck, and the power chip supplies power to a power amplifier of the pedestrian warning device.
[0024] The present invention adopts the above scheme and has the following advantages:
[0025] The audio device of the present invention sets a wake-up circuit between the vehicle-mounted system and the power circuit of the vehicle-mounted sound device, and judges whether the level of the signal connected to the wake-up signal input terminal meets the set wake-up condition through the voltage judgment module of the wake-up circuit. When the set wake-up condition is met, a high-level wake-up signal is output through the wake-up signal output terminal to wake up the power circuit to power the vehicle-mounted sound device. It can be compatible with high-voltage vehicle-mounted systems above 24V, is suitable for large transport vehicles such as trucks with higher vehicle-mounted system voltages, and can be used for waking up audio equipment such as pedestrian warning devices, entertainment or remote call speakers of large transport vehicles; there is no need to use a CAN chip with a wake-up function, etc., and the wake-up of the vehicle-mounted audio equipment can be achieved at a relatively low cost. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] In order to more clearly illustrate the technical solution of the present invention, the accompanying drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other accompanying drawings can be obtained based on these accompanying drawings without paying creative work.
[0027] Figure 1 The figure is a module diagram of an audio device according to an embodiment of the present invention.
[0028] Figure 2 The figure is a module diagram of a wake-up circuit according to an embodiment of the present invention.
[0029] Figure 3 4 is a circuit diagram of a wake-up circuit according to an embodiment of the present invention.
[0030] Figure 4 The figure is a wake-up flow chart of an audio device according to an embodiment of the present invention.
[0031] In the above figures,
[0032] 1. In-vehicle system; 11. ECU; 2. Wake-up circuit; 3. Power circuit; 4. Power amplifier; 5. Speaker;
[0033] 21. Wake-up signal input terminal; 22. Anti-reverse module; 23. Voltage division and filtering module; 24. Voltage judgment module; 25. Voltage protection module; 26. Wake-up signal output terminal. DETAILED DESCRIPTION
[0034] The preferred embodiments of the present invention are described in detail below in conjunction with the accompanying drawings so that the advantages and features of the present invention can be more easily understood by those skilled in the art. It should be noted that the description of these embodiments is used to help understand the present invention, but 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 can be combined with each other as long as they do not conflict with each other.
[0035] The following embodiments relate to audio equipment suitable for high voltage vehicle-mounted systems, and in particular to audio equipment wake-up circuits suitable for high voltage vehicle-mounted systems. The operating voltage of the high voltage vehicle-mounted system is above 24V, typically a 24V vehicle-mounted system; in other embodiments, it can be a 48V vehicle-mounted system. These vehicle-mounted systems are vehicle-mounted systems for large transport vehicles such as new energy trucks, which are powered by batteries.
[0036] Reference Figure 1 As shown, the audio device includes a vehicle-mounted sound device, a wake-up circuit 2, and a power circuit 3 for powering the vehicle-mounted sound device. "Vehicle-mounted sound device" refers to a device installed on a vehicle that can realize electroacoustic conversion and can play sound inside or outside the vehicle. In this embodiment, the audio device is typically a pedestrian warning device (AVAS) for a new energy truck. The pedestrian warning device is installed on the truck and emits a warning sound to the outside of the vehicle to remind pedestrians of the presence of the vehicle. The pedestrian warning device includes a speaker 5 that can realize electroacoustic conversion. In some other embodiments, the audio device may be an in-vehicle audio system that projects sound into the vehicle for entertainment or remote call functions, etc.; the in-vehicle audio system may include door panel speakers, headrest speakers, ceiling speakers, etc., and the sound frequency covers bass to high frequency bands. The power circuit 3 may include a power chip, such as an LDO or DCDC chip. The power 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 speaker 5 is driven by the power amplifier 4 to sound.
[0037] Combination Figure 2 and Figure 3As shown, the wake-up circuit 2 includes 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 accesses the wake-up signal from the high-voltage vehicle-mounted system 1 through the wake-up signal input terminal 21. In this embodiment, the wake-up signal input terminal 21 is connected to the vehicle-mounted 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-mounted sound unit, specifically to the wake pin of the power chip. The voltage judgment module 24 includes a transistor Q1 and a Zener 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 Zener 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 the set value, the wake-up signal output terminal 26 outputs a high-level signal. When the level of the signal connected to the wake-up signal input terminal 21 is lower than the set value, the wake-up signal output terminal 26 outputs a low-level signal.
[0038] The emitter of transistor Q1 is connected to a resistor R3, the base of transistor Q1 is connected to the first end of voltage-stabilizing diode D3 through resistor R4, and the second end of voltage-stabilizing diode D3 is grounded. Voltage judgment module 24 also includes capacitor C4, the first end of capacitor C4 is connected to resistor R3, and the second end of capacitor C4 is grounded; the connection point of resistor D3 and capacitor C4 is connected to the connection point of resistor R4 and the first end of voltage-stabilizing diode through a wire. In this embodiment, transistor Q1 is a PNP transistor, and voltage-stabilizing diode D3 is used as a clamping tube. The combination of PNP tube and clamping tube realizes the waking up when the voltage is lower than a set voltage (for example, 4V voltage) and the waking up when the voltage is higher than another set voltage (for example, 7V voltage). Finally, the back-end system is controlled by voltage division and clamping tube output voltage. Resistors R3 and R4 are used to drive transistor Q1, and capacitor C4 is used for filtering to prevent pulse spikes.
[0039] The wake-up circuit 2 also includes an anti-reverse module 22 and a voltage-dividing filter module 23, and the anti-reverse module 22, the voltage-dividing filter module 23 and the voltage judgment module 24 are arranged in sequence. The anti-reverse module 22 includes an anti-reverse diode D1, and the anti-reverse diode is 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 filter module 23 includes 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 between 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 with each other.
[0040] The voltage-dividing filter module 23 also includes an inductor FB1, which is connected in series between the resistor R1 and the emitter of the transistor Q1. The voltage-dividing filter module 23 also includes a transient voltage suppressor diode D2, the first end of which is connected to the connection point between the inductor FB1 and the emitter of the transistor Q1, and the second end of the transient voltage suppressor diode D2 is grounded. The capacitor includes a capacitor C1, a capacitor C2 and a capacitor C3, the first end of the capacitor C1 is connected to the connection point between the wake-up signal input terminal 21 and the anti-reverse diode D1, the first end of the capacitor C2 is connected to the connection point between the resistor R1 and the inductor FB1, the first end of the capacitor C3 is connected to the connection point between the inductor FB1 and the emitter of the transistor Q1, the capacitor C1, the capacitor C2, the resistor R2, the transient voltage suppressor diode D2 and the capacitor C3 are arranged in sequence, and the second ends of the capacitor C1, the capacitor C2 and the capacitor C3 are grounded. Among them, the resistor R1, the resistor R2 and the capacitor C1 constitute a voltage-dividing filter circuit. The transient voltage suppressor diode D2 is used to suppress transient voltage and protect the subsequent circuit. Inductor FB1, capacitor C2 and capacitor C3 play a π-type filtering role.
[0041] The wake-up circuit 2 further includes a voltage protection module 25, through which the collector of the transistor Q1 is connected to the wake-up signal output terminal 26. The voltage protection module 25 includes a voltage-stabilizing diode D4, a first end of which is connected to the connection point between the collector of the transistor Q1 and the wake-up signal output terminal 26, and a second end of the voltage-stabilizing diode D4 is grounded. The voltage-stabilizing diode D4 plays a clamping role, and can clamp to a fixed voltage at most.
[0042] The voltage protection module 25 also includes a resistor R5, a resistor R6 and a capacitor C5. The collector of the transistor Q1 is connected to the wake-up signal output terminal 26 through the resistor R5. The first end of the resistor R6 is connected to the connection point between the resistor R5 and the wake-up signal output terminal 26. The second end of the resistor R6 is grounded. The capacitor C5 is connected in parallel to the resistor R6. The resistors R5 and R6 play a role of voltage division, and the capacitor C5 plays a role of filtering and energy storage. The voltage protection module 25 also includes a capacitor C6. The first end of the capacitor C6 is connected to the wake-up signal output terminal 26, the second end of the capacitor C6 is grounded, and the capacitor C6 further performs filtering processing.
[0043] like 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 transistor Q1 are connected in series in sequence, and the collector of the transistor Q1, the resistor R5 and the wake-up signal output terminal 26 are connected in series in sequence. 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; capacitor C2 is connected in parallel on both sides of the resistor R2. One end of the diode D2 is connected to the connection point of the inductor FB1 and the emitter of the transistor Q1, and the other end is grounded; capacitor C3 is connected in parallel on both sides of the diode D2 and is located between the diode D2 and the emitter of the transistor Q1. Resistor R3 and capacitor C4 are connected in series to form a first branch connected to ground, and resistor R4 and diode D3 are connected in series to form a second branch connected to ground, and the first branch and the second branch are both located on the rear side of capacitor C3. The middle point of the first branch (the connection point of the resistor R3 and the capacitor C4) is connected to the middle point of the second branch (the connection point of the resistor R4 and the diode D3) through a wire. The capacitor C5 is connected between the collector of the transistor 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.
[0044] 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 electrical performance of the truck system, the wake-up control voltage of the audio equipment is required to be: below 4V, the electronic components are turned off, and greater than or equal to 7V must turn on the electronic components. The control buffer zone is between 4V and 7V.
[0045] The external input wake-up signal is input through the anti-reverse module 22 to prevent reverse voltage and protect the circuit; then it passes through the voltage divider filter module 23 to provide a stable voltage for the back end and eliminate interference signals; the voltage judgment module 24 is composed of a PNP tube plus a voltage regulator diode, and the voltage is lower than 4V to turn off the wake-up and higher than 7V to turn on the wake-up through voltage screening; finally, the output signal level is protected by the resistor voltage divider of the voltage protection module 25. Generally, when a large transport vehicle such as a truck is started, such as using a key to start or one-button start, the vehicle will send a wake-up signal to the AVAS, thereby starting the AVAS function.
[0046] Specifically, combined Figure 3As shown, starting from the input of the wake-up signal, the anti-reverse diode D1 is used for anti-reverse, which is used to protect the circuit from reverse voltage; the resistor R1 and the resistor R2 are used for voltage division and the filter circuit to provide a stable input voltage, and the voltage division ratio is 1:0.8; then it passes through the voltage judgment module 24, which is composed of a PNP tube Q1 combination and a voltage regulator diode D3. When the signal input voltage is higher than 7V, a tube voltage drop is formed through the emitter and base of Q1, and the voltage regulator diode D3 is used for voltage regulation, so that the PNP tube Q1 is in a conducting state and outputs a high-level voltage; when the signal input voltage is lower than 4V and passes through Q1, the emitter and base of the PNP tube cannot form a tube voltage drop, and Q1 is in a non-conducting state; the output voltage is divided and then protected by the voltage regulator diode D4, and finally the signal is output.
[0047] Combination Figure 4 As shown, when the wake-up signal input voltage is applied, after voltage division, it is determined whether the voltage after voltage division is greater than 5.2V; if the voltage after voltage division is less than 5.2V, the signal outputs a low level at this time, and if the voltage after voltage division is greater than 5.2V, the signal outputs a high level at this time, and finally outputs a high level signal after voltage division protection. In this embodiment, the design requirements are: greater than 7V input high level, less than 4V input low level; to design a voltage value between 4 and 7V, it is also necessary to combine the WAKE pin voltage of the power chip behind, so 5.2V is selected as the judgment comparison threshold. In other embodiments, the judgment comparison threshold is not necessarily this value, and the value is changed by modifying the resistance value according to different design requirements.
[0048] The audio device of this embodiment is provided with a wake-up circuit 2 between the vehicle-mounted system and the power circuit 3 of the vehicle-mounted sound device. The voltage judgment module 24 of the wake-up circuit 2 judges whether the level of the signal connected to the wake-up signal input terminal 21 meets the set wake-up condition. When the set wake-up condition is met, a high-level wake-up signal is output through the wake-up signal output terminal 26 to wake up the power circuit 3 to power the vehicle-mounted sound device. It is compatible with high-voltage vehicle-mounted systems above 24V, suitable for large transport vehicles such as trucks with higher vehicle-mounted system voltages, and can be used for waking up audio equipment such as pedestrian warning devices, entertainment or remote call speakers of large transport vehicles; there is no need to use a CAN chip with a wake-up function, etc., and the wake-up of the vehicle-mounted audio equipment can be achieved at a lower cost.
[0049] As shown in this specification and claims, the terms "comprises" and "includes" only indicate the inclusion of explicitly identified steps and elements, and these steps and elements do not constitute an exclusive list, and the method or device may also include other steps or elements.
[0050] It is further understood that in the present disclosure, "plurality" refers to two or more than two, and other quantifiers are similar thereto.
[0051] It is further 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 specific order or degree of importance. In fact, the expressions "first", "second", etc. can be used interchangeably. For example, without departing from the scope of the present disclosure, 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.
[0052] The above embodiment is only for illustrating the technical concept and features of the present invention, and is a preferred embodiment. Its purpose is to enable people familiar with this technology to understand the content of the present invention and implement it accordingly, and it cannot be used to limit the protection scope of the present invention.
Claims
1. An audio device suitable for a high-voltage vehicle-mounted system, comprising a vehicle-mounted sound device, a wake-up circuit and a power supply circuit for supplying power to the vehicle-mounted sound device; characterized in that: The wake-up circuit includes a wake-up signal input terminal, a voltage judgment module and a wake-up signal output terminal; the voltage judgment module receives the wake-up signal from the high-voltage vehicle system through the wake-up signal input terminal; The voltage judgment module includes a transistor and a voltage regulator diode D3, the emitter of the transistor is connected to the wake-up signal input terminal, the base of the transistor is connected to the voltage regulator diode D3, and the collector of the transistor is connected to the wake-up signal output terminal; The wake-up signal output terminal is connected to the power supply circuit.
2. The audio device according to claim 1, characterized in that The emitter of the transistor is connected to a resistor R3, the base of the transistor is connected to the first end of the Zener diode D3 through the resistor R4, and the second end of the Zener diode D3 is grounded; the voltage judgment module also includes 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 between the resistor D3 and the capacitor C4 is connected to the connection point between the resistor R4 and the first end of the Zener diode through a wire.
3. The audio device according to claim 1, characterized in that The wake-up circuit further includes an anti-reverse module and a voltage-dividing and filtering module, and the anti-reverse module, the voltage-dividing and filtering module and the voltage judgment module are arranged in sequence.
4. The audio device according to claim 3, characterized in that The anti-reverse module includes 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.
5. The audio device according to claim 4, characterized in that: The voltage divider filter module includes 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 between 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.
6. The audio device according to claim 5, characterized in that The voltage-dividing filter module further includes an inductor FB1, which is connected in series between the resistor R1 and the emitter of the transistor; The voltage dividing and filtering module further includes a transient voltage suppression diode D2, a first end of the transient voltage suppression diode D2 is connected to a connection point between the inductor FB1 and the emitter of the transistor, and a second end of the transient voltage suppression diode D2 is grounded; The capacitor includes capacitor C1, capacitor C2 and capacitor C3. The first end of capacitor C1 is connected to the connection point of the wake-up signal input terminal and the anti-reverse diode D1, the first end of capacitor C2 is connected to the connection point of resistor R1 and inductor FB1, the first end of capacitor C3 is connected to the connection point of inductor FB1 and the emitter of the transistor, capacitor C1, capacitor C2, resistor R2, transient voltage suppression diode D2 and capacitor C3 are arranged in sequence, and the second ends of capacitor C1, capacitor C2 and capacitor C3 are grounded.
7. The audio device according to any one of claims 1 to 6, characterized in that: The wake-up circuit further includes a voltage protection module, and the collector of the transistor is connected to the wake-up signal output terminal through the voltage protection module; The voltage protection module includes a voltage stabilizing diode D4 , a first end of the voltage stabilizing diode D4 is connected to a connection point between the collector of the transistor and the wake-up signal output terminal, and a second end of the voltage stabilizing diode D4 is grounded.
8. The audio device according to claim 7, characterized in that The voltage protection module further includes a resistor R5, a resistor R6 and a capacitor C5, the collector of the transistor is connected to the wake-up signal output terminal through the resistor R5, the first end of the resistor R6 is connected to the connection point between the resistor R5 and the wake-up signal output terminal, the 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 includes 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. The audio device according to claim 1, characterized in that: The vehicle-mounted system is a 24V vehicle-mounted system. When the level of the signal connected to the wake-up signal input terminal is higher than the set value, the wake-up signal output terminal outputs a high-level signal. When the level of the signal connected to the wake-up signal input terminal is lower than the set value, the wake-up signal output terminal outputs a low-level signal.
10. The audio device according to claim 1, characterized in that The power circuit includes a power chip, and the wake-up signal output terminal is connected to the wake pin of the power chip; the vehicle-mounted sound device includes a pedestrian warning device installed on a truck, the vehicle-mounted system is the vehicle-mounted system of the truck, and the power chip supplies power to the power amplifier of the pedestrian warning device.