Loudspeaker control method and device, electronic equipment and storage medium

Abstract

The invention discloses a loudspeaker control method and device, electronic equipment and a storage medium, the loudspeaker control method is applied to the electronic equipment, the electronic equipment comprises a loudspeaker and a power amplifier, and the loudspeaker control method comprises the following steps: under the condition that the electronic equipment is in a falling state, the power amplifier is connected with the loudspeaker; acquiring a feedback voltage signal of the loudspeaker; and outputting an inverted signal to the loudspeaker through the power amplifier, wherein the phase of the inverted signal is opposite to the phase of the feedback voltage signal. According to the method, the possibility that the power amplifier is damaged due to falling of the electronic equipment can be reduced.

Description

Technical Field

[0001] This application relates to the technical field of electronic devices, and more particularly, to a control method, device, electronic device, and storage medium for a speaker. Background Art

[0002] With the rapid progress of technology and living standards, electronic devices (such as smart phones, tablets, etc.) have become one of the commonly used electronic products in people's lives. In the actual use of electronic devices, the situation where the electronic device drops may occur. When the electronic device drops, the power amplifier in the audio playback system is easily damaged. Summary of the Invention

[0003] This application provides a control method, device, electronic device, and storage medium for a speaker, which can reduce the possibility of the power amplifier being damaged due to the dropping of the electronic device.

[0004] In a first aspect, an embodiment of this application provides a control method for a speaker, which is applied to an electronic device. The electronic device includes a speaker and a power amplifier. The method includes: when the electronic device is in a dropped state, obtaining a feedback voltage signal of the speaker; outputting an anti-phase signal to the speaker through the power amplifier, and the phase of the anti-phase signal is opposite to the phase of the feedback voltage signal.

[0005] In a second aspect, an embodiment of this application provides a control device for a speaker, which is applied to an electronic device. The electronic device includes a speaker and a power amplifier. The device includes: a signal acquisition module and a signal output module. Among them, the signal acquisition module is configured to obtain a feedback voltage signal of the speaker when the electronic device is in a dropped state; the signal output module is configured to output an anti-phase signal to the speaker through the power amplifier, and the phase of the anti-phase signal is opposite to the phase of the feedback voltage signal.

[0006] In a third aspect, an embodiment of this application provides an electronic device, including: one or more processors; a memory; one or more application programs, where the one or more application programs are stored in the memory and configured to be executed by the one or more processors, and the one or more application programs are configured to execute the control method for the speaker provided in the first aspect above.

[0007] In a fourth aspect, an embodiment of this application provides a computer-readable storage medium, in which program code is stored, and the program code can be called by a processor to execute the control method for the speaker provided in the first aspect above.

[0008] The solution provided by this application obtains the feedback voltage signal of the speaker when the electronic device is in a falling state, and outputs an inverted signal to the speaker through a power amplifier. The phase of the inverted signal is opposite to the phase of the feedback voltage signal. Thus, when the electronic device drops, by outputting an inverted signal to the speaker, the back electromotive force generated by the speaker during the falling process can be cancelled out, and further, the return current generated by the back electromotive force from burning out the power amplifier can be avoided. Without adding new components inside the electronic device, the possibility of the power amplifier being damaged due to the electronic device falling can be reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] To more clearly illustrate the technical solutions in the embodiments of this application, the following briefly introduces the accompanying drawings required for the description of the embodiments. Obviously, the accompanying drawings in the following description are only some embodiments of this application. For those skilled in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0010] Figure 1 FIG. shows a schematic diagram of the application environment provided by the embodiments of this application.

[0011] Figure 2 FIG. shows a schematic flowchart of a method for controlling a speaker according to an embodiment of this application.

[0012] Figure 3 FIG. shows a schematic flowchart of a method for controlling a speaker according to another embodiment of this application.

[0013] Figure 4 FIG. shows a schematic flowchart of a method for controlling a speaker according to still another embodiment of this application.

[0014] Figure 5 FIG. shows a schematic flowchart of a method for controlling a speaker according to yet another embodiment of this application.

[0015] Figure 6 FIG. shows a schematic diagram of the principle of the method for controlling a speaker provided by the embodiments of this application.

[0016] Figure 7 FIG. shows a block diagram of a control device for a speaker according to an embodiment of this application.

[0017] Figure 8 is a block diagram of an electronic device for executing the method for controlling a speaker according to the embodiments of this application.

[0018] Figure 9 is a storage unit for storing or carrying the program code for implementing the method for controlling a speaker according to the embodiments of this application. Detailed implementation manners

[0019] In order to enable those skilled in the art to better understand the solutions of this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of this application.

[0020] Currently, an audio playback system is usually provided in an electronic device. In the audio playback system, an audio signal is usually amplified by a power amplifier and then output to a speaker, so that audio playback can be realized. In the daily use of an electronic device, it is inevitable that the mobile phone will fall. During the process of the electronic device falling, the coil in the speaker will move relative to the magnet, resulting in the situation where the coil cuts the magnetic field lines. According to Lenz's law: E = B * L * V0, where B is the magnetic field strength of the magnet in the speaker, L is the length of the coil in the speaker, and V0 is the moving speed of the coil, a back electromotive force (negative voltage) will be generated. Moreover, the negative voltage generated during the falling process will be relatively large, which will further cause the return current in the circuit to be too large, resulting in the situation of burning out the power amplifier.

[0021] In the related art, a unidirectional transient voltage suppressor (TVS) can be added to the line output by the speaker. By guiding the shunt, the current generated by the back electromotive force does not pass through the power amplifier, thereby avoiding damage to the power amplifier due to the falling of the electronic device. However, this will increase the hardware cost of the electronic device and occupy the layout space inside the electronic device; in addition, the TVS tube has a capacitance effect and filters the high-frequency part of the pulse width modulation (PWM) in the output audio, resulting in distortion of the audio signal and affecting the audio playback effect.

[0022] In view of the above problems, the inventors proposed a control method, device, electronic device, and storage medium for a speaker provided in the embodiments of this application. When the electronic device falls, a reverse signal can be output to the speaker, thereby canceling the back electromotive force generated by the speaker during the falling process, and further avoiding the return current generated by the back electromotive force from burning out the power amplifier, realizing the possibility of reducing the damage of the power amplifier due to the falling of the electronic device without adding new devices inside the electronic device. Among them, the specific control method of the speaker will be described in detail in the subsequent embodiments.

[0023] The scenarios involved in the embodiments of this application will be introduced below.

[0024] As Figure 1 shown, in Figure 1The scene shown includes an electronic device 100, which may include an Application Processor (AP) 101, a Digital Signal Processor 102, a Power Amplifier 103, and a Speaker 104. Among them, the application processor can be communicatively connected to the digital signal processor 102, the digital signal processor 102 can be communicatively connected to the power amplifier 103, and the power amplifier 103 can be connected to the speaker 104; the application processor 101 is the core computing unit of electronic devices such as smartphones, tablets, and smart wearable devices, and is responsible for running the operating system and various application programs installed by users; the Digital Signal Processor (DSP) is a microprocessor optimized for digital signal processing tasks and can efficiently execute operations such as real-time signal analysis, filtering, transformation, and encoding. Through hardware acceleration and instruction set optimization, the DSP has significant performance advantages when processing digital signals; the power amplifier is mainly used to amplify the weak electrical signal from the signal source to drive the speaker to emit sound.

[0025] When the electronic device 100 plays audio, the application processor 101 can output an audio signal to the digital signal processor 102, and then the digital signal processor 102 processes the audio signal such as equalization, sound effect enhancement, and noise suppression, and then outputs the processed audio signal to the power amplifier 103; the power amplifier 103 receives the processed audio signal, amplifies the power and then outputs it to the speaker 104, and then the speaker 104 converts the amplified electrical signal into a sound signal to emit sound.

[0026] When implementing the protection of the power amplifier in the case of the electronic device 100 falling, in the case where the electronic device 100 is in a falling state, the feedback voltage signal of the speaker 104 can be obtained, and then an inverted signal is output to the speaker 104 through the power amplifier 103. The phase of the inverted signal is opposite to the phase of the feedback voltage signal, so as to be able to cancel the back electromotive force generated by the speaker 104 during the fall and avoid the return current generated by the back electromotive force from burning out the power amplifier.

[0027] Next, the control method of the speaker provided by the embodiment of the present application will be introduced in detail with reference to the accompanying drawings.

[0028] Please refer to Figure 2 , Figure 2 which shows a schematic flow chart of the control method of the speaker provided by an embodiment of the present application. The control method of the speaker is applied to the above-mentioned electronic device. Next, the Figure 2 shown process will be elaborated in detail. The control method of the speaker may specifically include the following steps:

[0029] Step S110: When the electronic device is in a falling state, obtain the feedback voltage signal of the speaker.

[0030] In the embodiments of the present application, the falling state may refer to the state when the electronic device falls, and the feedback voltage signal may refer to the voltage signal fed back by the speaker. When the electronic device falls, the coil will move along with the fall, and the movement of the coil will cut the magnetic field in the speaker, thereby generating a back electromotive force. The back electromotive force will cause a return current to be input into the power amplifier, and then the power amplifier may be burned out. To avoid the above problems, the electronic device can detect its falling state; when the electronic device detects its falling state, it can obtain the feedback voltage signal of the speaker, that is, the voltage signal across the speaker at this time, so as to perform corresponding control on the speaker according to the feedback voltage signal to protect the power amplifier.

[0031] In some embodiments, since the acceleration of the electronic device and the attitude of the electronic device will change when the electronic device falls, the motion data collected by the motion sensor provided in the electronic device can be obtained, and whether the electronic device is in a falling state can be determined according to the motion data. Among them, the motion data collected by the motion sensor can be matched with the target motion condition. According to the matching result, if the motion data meets the target motion condition, it can be determined that the electronic device is in a falling state; if the motion data does not meet the target motion condition, it can be determined that the electronic device is not in a falling state. The target motion condition may be the condition satisfied by the motion data when the electronic device falls.

[0032] In a possible embodiment, the target motion condition may be determined according to the motion data of the test device when it falls multiple times in advance. Optionally, the average value of the motion data can be determined according to the motion data of the test device when it falls multiple times, and this average value can be used as the target motion condition. When matching the detected motion data of the electronic device with the target motion condition, the motion data can be matched with this average value. If the motion data of the electronic device matches this average value, it can be determined that the electronic device is in a falling state; if the motion data of the electronic device does not match this average value, it can be determined that the electronic device is not in a falling state. For example, when the electronic device falls, it is in a free-fall state, then a large vertical downward acceleration is detected within a short period of time (such as dozens of milliseconds). Accordingly, it can be determined whether it is in a falling state according to the acceleration data of the electronic device.

[0033] In a possible implementation, the motion sensor may include at least one of a gravity sensor, an acceleration sensor, a gyroscope sensor, and a multi-axis sensor (such as a six-axis sensor or a nine-axis sensor) that combines an acceleration sensor and a gyroscope sensor. The gravity sensor is implemented through the piezoelectric effect. Inside the gravity sensor, a heavy object is integrated with a piezoelectric sheet. By calculating the voltage magnitudes generated in two orthogonal directions, the horizontal direction can be determined. When the gravity sensor is used in an electronic device, it is usually used to switch between landscape and portrait orientations; the gyroscope, also known as an angular velocity sensor, is usually a three-axis gyroscope configured in an electronic device, which can track displacement changes in six directions, obtain the angular accelerations of the electronic device in the x, y, and z directions, and measure the rotation and deflection actions of the mobile phone well, so as to perform corresponding operations on the electronic device. In an electronic device, the applications that usually use the gyroscope include games, camera anti-shake, navigation, etc.; the acceleration sensor is used to detect the accelerations in three mutually perpendicular axes, which can be the x-axis, y-axis, and z-axis. The plane formed by the x-axis and y-axis is the plane where the screen is located, and the x-axis and y-axis are perpendicular to each other. The z-axis is perpendicular to the plane formed by the x-axis and y-axis, and the z-axis can take the vertically downward direction as the positive direction.

[0034] Of course, the specific method for the electronic device to determine whether it is in a falling state may not be limited. For example, it can also input the detected motion data into a pre-trained falling state detection model, and determine whether the electronic device is in a falling state according to the result output by the falling state detection model.

[0035] In some implementations, a voltage detection module can be added to the circuit of the speaker. The voltage detection module can use an operational amplifier and an analog-to-digital converter (ADC), so that the voltage signal across the speaker can be amplified and digitized by the voltage detection module; the digitized voltage signal can be transmitted to the processor of the electronic device through a serial communication interface (such as I2C or SPI), for example, transmitted to the application processor; the processor can further analyze and process these signals to obtain detailed information about the feedback voltage of the speaker, including the voltage magnitude, frequency, and phase, etc.

[0036] In some implementations, the power amplifier in the electronic device can be a smart power amplifier. The smart power amplifier is based on the traditional power amplifier and adds a current-voltage acquisition module at the output end, such as adding a current-voltage sensor (IV sensor). The current-voltage acquisition module is connected to the signal line connecting the smart power amplifier and the speaker, so as to realize the detection of the current and voltage of the speaker.

[0037] In a possible implementation, the power amplifier can transmit the acquired feedback voltage signal to the digital signal processor through a communication connection with the digital signal processor, and then the digital signal processor transmits the feedback voltage signal to the application processor. Among them, the power amplifier and the digital signal processor can communicate through a digital control interface, a high-speed data interface, etc.; the digital control interface can include an Inter-IC Sound (IIS) interface, a Serial Peripheral Interface (SPI), an Inter-Integrated Circuit (IIC), etc.; the high-speed data interface can include a High-Definition Multimedia Interface (HDMI), a Low-Voltage Differential Signaling (LVDS) interface, etc. Of course, in the embodiments of the present application, the specific communication method between the power amplifier and the digital signal processor may not be limited.

[0038] In addition, the digital signal processor and the application processor can transmit data through a System on Chip (SOC) internal integrated architecture, an external interface connection, a shared memory, etc. The system on chip usually integrates the application processor and the digital signal processor on the same chip and realizes high-speed data transmission through an internal bus. The external interface connection method can include a high-speed serial interface, a parallel bus, a dedicated hardware accelerator interface, etc. Among them, if the application processor and the digital signal processor are independent chips, they can be connected through a high-speed interface such as a Peripheral Component Interconnect Express (PCIe); the parallel bus can include a Double Data Rate (DDR) interface, etc. Of course, the specific data transmission method between the digital signal processor and the application processor may not be limited.

[0039] Optionally, considering that the duration of the electronic device falling is short, in order to reduce the delay in controlling the speaker and improve the response speed of the electronic device when it falls, the digital signal processor and the application processor can transmit the feedback voltage signal through the shared memory. Among them, the digital signal processor can write the feedback voltage signal into the shared memory area between the digital signal processor and the application processor, and then the application processor reads the feedback voltage signal from this shared memory area. Among them, shared memory is a technology that allows different processors or cores to access the same physical memory area. Through shared memory, the digital signal processor can directly write the feedback voltage signal into the shared memory area, and the application processor can read this data in real time. In the above method, a feedback path is created through the shared memory to transmit the feedback voltage signal of the speaker to the application processor, avoiding the overhead brought by traditional data transmission methods (such as interrupts or message queues), improving the data transmission efficiency, and thus reducing the delay in controlling the speaker.

[0040] In the above embodiment, a part of the memory area can be allocated on the application processor side as the above shared memory area. Among them, a target number of memory pages can be allocated for the feedback voltage signal of the speaker, and the target number can be determined according to the data volume of the feedback voltage signal obtained each time. That is to say, the target number of memory pages can store at least once the obtained feedback voltage signal. A memory page is a management unit of memory management. In the memory paging storage management, the virtual memory space of a process is divided into several equal-sized slices, called pages; the page sizes are different, such as 4KB pages, 16KB pages, 64KB pages, 2MB pages, 1GB pages, etc.

[0041] Optionally, considering that during the audio playback process, it is necessary to continuously and in real-time feedback the feedback voltage signal of the speaker, the memory page corresponding to the above feedback voltage signal should not be swapped out during the audio playback process. To prevent the electronic device from swapping out the above memory page to other storage areas outside the memory during memory management, such as swapping it out to areas in flash memory or disks, etc., the page priority corresponding to the above memory page can be set to the highest page priority to avoid being swapped out due to the relatively low page priority of the above memory page, thereby affecting the real-time nature of data transmission. Among them, memory swapping is a traditional memory management strategy that allows the operating system to "swap out" data in memory to storage media such as hard disks, compress it to other memory areas, flash memory, etc. to free up memory space for other processes. When the "swapped out" data is needed again, the operating system will "swap it back" from the above storage media to memory. However, if the above storage media is a physical disk, due to the access rate limitation of the physical disk (the current mainstream disk read and write rate is usually at the level of hundreds of megabytes per second), the entire process is very time-consuming. During this process, the user may feel that the system is extremely slow.

[0042] In the above embodiments, the page priority of the memory page can be determined based on at least one of the access frequency, importance level, and modification frequency of the memory page. Among them, the importance level of the memory page can be determined based on at least one of the importance level of its affiliated running entity and the memory usage requirements. The running entity can be the importance level of an application program, an affiliated system service, an affiliated process, etc.; for different page priorities, the higher the page priority, the higher the access frequency, importance level, and modification frequency of the corresponding memory page.

[0043] Step S120: Output an inverted signal to the speaker through the power amplifier, where the phase of the inverted signal is opposite to the phase of the feedback voltage signal.

[0044] In the embodiments of the present application, after the processor (which can be an application processor) in the electronic device obtains the feedback voltage signal of the speaker, it can output an inverted signal with a phase opposite to that of the feedback voltage signal to the speaker through the power amplifier. This inverted signal can be an inverted voltage signal. Thus, the inverted signal output to the speaker can cancel the back electromotive force generated by the speaker during the drop process, thereby preventing the backflow current generated by the back electromotive force from burning out the power amplifier.

[0045] In some embodiments, the processor of the electronic device may calculate an anti-phase signal to be output according to the feedback voltage signal of the speaker. The generation of the anti-phase signal may be implemented by a digital signal processing algorithm to ensure that it matches the anti-phase signal generated by the speaker in terms of amplitude and frequency, but the phase is opposite. Then, the processor may transmit the calculated anti-phase signal to the power amplifier, and the power amplifier amplifies the input anti-phase signal and outputs it to the speaker to ensure that the output anti-phase signal can accurately cancel the anti-phase electromotive force generated by the speaker.

[0046] The control method for the speaker provided by the embodiments of the present application can achieve that when the electronic device drops, by outputting an anti-phase signal to the speaker, the anti-phase electromotive force generated by the speaker during the drop process can be cancelled, thereby avoiding the return current generated by the anti-phase electromotive force from burning out the power amplifier. Without adding new components inside the electronic device, it is possible to reduce the possibility of the power amplifier being damaged due to the drop of the electronic device, and it will not increase the hardware cost of the electronic device due to setting a TVS tube in the speaker circuit, nor will it affect the internal layout space of the electronic device, and it also avoids the distortion of the audio signal, ensuring the audio playback effect of the electronic device.

[0047] Please refer to Figure 3 , Figure 3 which shows a schematic flowchart of the control method for the speaker provided by another embodiment of the present application. This control method for the speaker is applied to the above-mentioned electronic device. The following will elaborate in detail on the Figure 3 shown process. The control method for the speaker may specifically include the following steps:

[0048] Step S210: When the electronic device is in a dropped state, obtain the feedback voltage signal of the speaker.

[0049] In the embodiments of the present application, for the content of step S210, reference may be made to the content of other embodiments, which will not be elaborated here.

[0050] Step S220: Output a first anti-phase signal to the power amplifier, where the phase of the first anti-phase signal is opposite to the phase of the feedback voltage signal.

[0051] In the embodiments of the present application, when the processor of the electronic device outputs an anti-phase signal to the speaker through the power amplifier, it may output a first anti-phase signal to the power amplifier. The phase of this first anti-phase signal is opposite to the phase of the feedback voltage signal of the speaker, so that after the power amplifier processes this first anti-phase signal and outputs it to the speaker, it can cancel the anti-phase electromotive force generated by the speaker during the drop.

[0052] Step S230: Output a second inverted signal amplified from the first inverted signal to the speaker through the power amplifier, where the amplitude of the second inverted signal matches the amplitude of the feedback voltage signal.

[0053] In the embodiment of the present application, after the first inverted signal is output to the power amplifier, the power amplifier can amplify the first inverted signal and output the amplified second inverted signal to the speaker. Moreover, for the inverted signal output by the power amplifier, the amplitude of the second inverted signal amplified from the first inverted signal matches the amplitude of the feedback voltage signal of the speaker, so as to ensure that the back electromotive force generated when the speaker drops can be cancelled.

[0054] In some embodiments, to ensure that the amplitude of the second inverted signal output by the power amplifier matches the amplitude of the feedback voltage signal of the speaker, it can be that the amplitude of the first inverted signal output by the processor of the electronic device to the power amplifier matches the amplitude of the feedback voltage signal. In such a case, the power amplifier can amplify the first inverted signal in the unity gain mode and output the amplified second inverted signal to the speaker.

[0055] Among them, the unity gain mode of the power amplifier is a special operating mode. In this mode, the gain of the amplifier is set to 1, which means that the amplitude of the output signal is equal to the amplitude of the input signal, without amplification or attenuation, so that the power amplifier only amplifies the power of the first inverted signal without changing its amplitude, so that the amplified second inverted signal still has the same amplitude as the first inverted signal, and thus can cancel the back electromotive force generated when the speaker drops. In the above way, the control logic can be simplified, the delay can be reduced, and the introduction of noise or distortion caused by gain adjustment can be avoided.

[0056] In some embodiments, to ensure that the amplitude of the second inverted signal output by the power amplifier matches the amplitude of the feedback voltage signal of the speaker, it can also be that after the power amplifier amplifies the inverted signal input by the processor in the fixed gain mode, the amplitude of the finally output inverted signal to the speaker matches the amplitude of the feedback voltage signal. Among them, the power amplifier can amplify the first inverted signal in the fixed gain mode and output the amplified second inverted signal to the speaker, and the gain of the power amplifier in the fixed gain mode is determined according to the amplitude of the first inverted signal and the amplitude of the feedback voltage signal.

[0057] Among them, the fixed gain mode of the power amplifier means that when the amplifier is in a specific operating state, its gain value is set to a fixed value and will not change with the change of the input signal. This mode is of great significance in the design of the power amplifier and can ensure that the signal maintains a stable gain characteristic during the amplification process. In order to ensure that the amplitude of the second inverted signal amplified by the power amplifier from the first inverted signal output by the processor matches the amplitude of the feedback voltage signal of the speaker, when the processor of the electronic device outputs the first inverted signal to the power amplifier, it can determine the amplitude of the first inverted signal according to the gain of the power amplifier and the amplitude of the feedback voltage signal, so as to ensure that after the power amplifier amplifies the first inverted signal according to a fixed gain, the amplitude of the amplified second inverted signal matches the amplitude of the feedback voltage signal of the speaker. Exemplarily, if the amplitude of the above feedback voltage signal is 6 and the gain of the power amplifier is 2 times the gain, then the amplitude of the first inverted signal output to the power amplifier can be 6 / 2 = 3, so that the amplitude of the second inverted signal after being amplified by the power amplifier is 6, which can match the amplitude of the feedback voltage signal.

[0058] The control method of the speaker provided by the embodiment of the present application is to, when the electronic device drops, output an inverted signal to the speaker, so as to cancel the back electromotive force generated by the speaker during the dropping process, and further avoid the return current generated by the back electromotive force from burning out the power amplifier, realizing the possibility of reducing the damage of the power amplifier of the electronic device due to dropping without adding new components in the electronic device; and, the amplitude of the inverted signal amplified by the power amplifier matches the amplitude of the feedback voltage signal of the speaker, so as to ensure that the back electromotive force generated by the speaker due to dropping can be completely cancelled.

[0059] Please refer to Figure 4 , Figure 4 FIG. shows a schematic flow chart of a control method of a speaker provided by another embodiment of the present application. This control method of the speaker is applied to the above-mentioned electronic device. The following will elaborate in detail on the Figure 4 shown process. The control method of the speaker may specifically include the following steps:

[0060] Step S310: When the electronic device is in a dropping state, obtain the feedback voltage signal of the speaker.

[0061] In the embodiment of the present application, step S310 may refer to the content of other embodiments and will not be elaborated here.

[0062] Step S320: During the process that the electronic device is in a dropping state, continuously output an inverted signal to the speaker through the power amplifier, and the phase of the inverted signal is opposite to the phase of the feedback voltage signal.

[0063] In the embodiments of the present application, since the electronic device will remain in the falling state for a certain period of time when it falls, the electronic device, when in the falling state, can continuously output an anti-phase signal opposite to the phase of the feedback voltage signal of the speaker to the speaker through the power amplifier during the process of being in the falling state.

[0064] In some embodiments, considering that the falling speed of the electronic device changes during the falling process and increases with the increase of the falling duration, according to Lenz's law E = B * L * V0, where B is the magnetic field strength of the magnet in the speaker, L is the length of the coil in the speaker, and V0 is the moving speed of the coil, the back electromotive force generated by the speaker during the fall will increase. In addition, it takes time to detect the feedback voltage signal of the speaker and transmit the feedback voltage signal to the processor, and the falling speed of the electronic device can be obtained faster. Therefore, in order to avoid control delay and ensure that the anti-phase signal output to the speaker can cancel the back electromotive force generated by the speaker, the amplitude of the anti-phase signal can also be adjusted according to the falling speed of the electronic device when it is in the falling state, so as to ensure that during the process of the electronic device being in the falling state, the amplitude of the anti-phase signal output to the speaker can match the amplitude of the back electromotive force generated by the speaker, and thus the cancellation effect can be guaranteed.

[0065] In a possible embodiment, since the electronic device is in a free-fall state when it falls, and detecting the falling speed through relevant motion sensors may cause delay, in order to adjust the amplitude of the anti-phase signal output to the speaker more real-time, the corresponding relationship between different durations and amplitudes can be determined in advance according to the gravitational acceleration and Lenz's law. Among them, the falling speed at different durations can be determined according to the gravitational acceleration; then according to Lenz's law E = B * L * V0, the magnitude of the back electromotive force generated by the speaker at different durations can be determined, and this magnitude can be used as the amplitude of the anti-phase signal to be output, so as to establish the corresponding relationship between different durations and amplitudes.

[0066] In the above embodiments, during the process of the electronic device being in the falling state, when dynamically adjusting the amplitude of the output anti-phase signal, the amplitude of the anti-phase signal can be adjusted to the amplitude corresponding to the current moment according to the above corresponding relationship between the duration and amplitude of the electronic device when it is in the falling state. Among them, the amplitude corresponding to the current duration can be determined according to the current duration when in the falling state and the above corresponding relationship, and then the amplitude of the output anti-phase signal can be adjusted to the amplitude corresponding to the current duration.

[0067] In a possible implementation manner, during the process that the electronic device is in a falling state, when dynamically adjusting the amplitude of the output anti-phase signal, it may be directly adjusting the amplitude of the reverse signal output from the processor of the electronic device to the power amplifier, so that the amplitude of the reverse signal output to the power amplifier is the same as the amplitude corresponding to the current duration, and the power amplifier adopts the unity gain mode, thereby enabling the anti-phase signal output from the power amplifier to the speaker to cancel the back electromotive force generated by the speaker during the fall.

[0068] In a possible implementation manner, during the process that the electronic device is in a falling state, when dynamically adjusting the amplitude of the output anti-phase signal, it may be determining the amplitude of the reverse signal output to the power amplifier according to the amplitude corresponding to the current duration and the gain of the power amplifier in the fixed gain mode, so that the amplitude of the anti-phase signal amplified by the power amplifier in the fixed gain mode is the same as the amplitude corresponding to the current moment, and further enabling the anti-phase signal output from the power amplifier to the speaker to cancel the back electromotive force generated by the speaker during the fall.

[0069] The control method of the speaker provided by the embodiments of the present application is to, when the electronic device falls, output an anti-phase signal to the speaker, thereby canceling the back electromotive force generated by the speaker during the fall, and further avoiding the backflow current generated by the back electromotive force from burning out the power amplifier, and realizing the possibility of reducing the damage of the power amplifier of the electronic device due to falling without adding new components inside the electronic device; in addition, during the process that the electronic device is in a falling state, dynamically adjusting the amplitude of the output anti-phase signal according to the falling speed of the electronic device can, on the one hand, adjust the amplitude of the anti-phase signal more real-time, and on the other hand, ensure that during the process that the electronic device is in a falling state, the amplitude of the anti-phase signal output to the speaker can match the amplitude of the back electromotive force generated by the speaker, and further ensure the cancellation effect.

[0070] Please refer to Figure 5 , Figure 5 which shows a schematic flow chart of the control method of the speaker provided by another embodiment of the present application. This control method of the speaker is applied to the above-mentioned electronic device. The following will elaborate in detail on Figure 5 the flow shown, and the control method of the speaker may specifically include the following steps:

[0071] Step S410: Obtain the status data collected by the target sensor, where the target sensor includes at least one of a motion sensor, a barometer, and an ultrasonic sensor.

[0072] In the embodiments of the present application, considering that there will be a delay in controlling the speaker when the electronic device detects a fall, when implementing the protection of the power amplifier when the electronic device falls, it is possible to predict whether the electronic device is about to fall, so as to better protect the power amplifier. When predicting whether the electronic device is about to fall, the status data collected by the target sensor can be obtained, and the status data collected by the target sensor is strongly correlated with the status when the electronic device falls. The target sensor may include at least one of a motion sensor, a barometer, and an ultrasonic sensor. The motion sensor may include an acceleration sensor, a gyroscope, etc.

[0073] Understandably, the accelerometer can monitor the motion state of the electronic device in real time. When the electronic device suddenly accelerates or decelerates (such as slipping from the hand), the acceleration data will change abnormally; by analyzing the instantaneous change rate of the acceleration, it can be detected whether the electronic device is in an unstable state. For example, when the acceleration change rate exceeds a certain threshold, the system can determine that the electronic device has a risk of falling. Accordingly, it can be predicted whether the electronic device will be in a falling state. The gyroscope can detect the rotation and direction change of the electronic device. When the electronic device slips from the hand, it usually accompanies rotation or flipping actions. Combining the data of the accelerometer, the gyroscope can provide more comprehensive motion information to help determine whether the electronic device is in a free fall state. The barometer can detect the change of the ambient air pressure. When the electronic device falls from a high place, the air pressure data may change suddenly. Although the sensitivity of the barometer is limited, it can be used as an auxiliary sensor. The ultrasonic sensor can detect the distance between the electronic device and the surrounding objects. If the electronic device is close to the edge or the edge of the table, the sensor can give an early warning.

[0074] Step S420: Input the status data into a pre-trained fall prediction model to obtain a fall prediction result output by the fall prediction model.

[0075] In the embodiments of the present application, after obtaining the above status data, the obtained status data can be input into a pre-trained fall prediction model, so as to obtain a fall prediction result output by the fall prediction model. The fall prediction model is used to predict whether the electronic device will be in a falling state according to the input status data, and the fall prediction result output by the fall prediction model can represent whether the electronic device will be in a falling state.

[0076] In some embodiments, the drop prediction model can learn the precursors of drops (such as sudden acceleration changes, abnormal postures, etc.) of the test device under different drop scenarios, so as to output a drop prediction result for the input state data. Among them, the state data collected by the target sensor before the test device is truly in the drop state under different drop scenarios can be obtained and used as positive sample state data; the positive sample state data can be labeled with a drop label, and the drop label labeled on the positive sample state data is used to characterize that the electronic device will be in the drop state. In addition, the state data collected by the target sensor of the test device in the normal use scenario can be obtained and used as negative sample state data; the negative sample state data can also be labeled with a drop label, and the drop label labeled on the negative sample state data is used to characterize that the electronic device will not be in the drop state. According to the above positive sample data and negative sample data, a sample state data set can be obtained, and the initial prediction model can be trained using the sample state data set, so that the trained drop prediction model can be obtained. The specific model type of the above initial prediction model can be not limited. For example, it can be a neural network model.

[0077] In a possible embodiment, when training the initial prediction model using the above sample state data set, the sample state data in the sample state data set can be input into the initial prediction model to obtain the result output by the initial prediction model, and the loss value can be determined according to the output result and the drop label labeled on the sample state data set; then, according to the determined loss value, the model parameters of the initial prediction model can be adjusted; then return to the step of inputting the sample state data in the sample state data set into the initial prediction model to obtain the result output by the initial prediction model, until the training end condition is met, and the trained drop prediction model can be obtained. Among them, the above loss value can be calculated based on the binary cross-entropy function.

[0078] Among them, after each sample state data is input into the initial prediction model respectively to obtain the output result corresponding to each sample state data, and then the loss value is determined according to the output result corresponding to each sample state data and the drop label labeled on each sample state data, and then the model parameters of the initial prediction model are adjusted according to the determined loss value, 1 epoch (round) is completed; then return to the step of inputting the sample state data in the sample state data set into the initial prediction model to obtain the result output by the initial prediction model, complete the next epoch, and repeat in this way to complete multiple epochs. Among them, epoch refers to the number of times of using all the sample state data, and 1 epoch is equal to training once using all the sample state data.

[0079] In the above embodiments, the initial prediction model can be iteratively updated using the Adam optimizer according to the loss value, so that the loss value obtained each time becomes smaller until the above total loss value converges, and the model at this time is saved to obtain the trained drop prediction model. Among them, the Adam optimizer combines the advantages of the AdaGra (Adaptive Gradient) and RMSProp optimization algorithms, comprehensively considers the first moment estimation of the gradient (First Moment Estimation, that is, the mean of the gradient) and the second moment estimation (Second Moment Estimation, that is, the uncentered variance of the gradient), and calculates the update step size. Among them, the training end conditions for iterative training can include: the number of iterations reaches the target number; or the above loss value meets the set conditions. The convergence condition is to make the loss value as small as possible. Using the initial learning rate of 1e-3, the learning rate decays cosine with the number of steps, batch_size = 512. After training for multiple epochs, it can be considered that the convergence is completed. batch_size can be understood as a batch processing parameter, and its limit value is the total number of sample state data.

[0080] Optionally, the total loss value meeting the set conditions can include: the total loss value is less than the set threshold. Of course, the specific set conditions can be not limited.

[0081] It should be noted that the training of the drop prediction model can be pre-performed according to the sample state data. Subsequently, each time it is necessary to predict the drop state of the electronic device, the trained drop prediction model can be used, instead of training the drop prediction model each time when predicting the drop state of the electronic device. In addition, the training of the above drop prediction model can be completed by other devices. For example, after the server trains and completes the drop prediction model, the drop prediction model can be deployed to the electronic device.

[0082] Step S430: If the drop prediction result indicates that the electronic device will be in a drop state, obtain the feedback voltage signal of the speaker.

[0083] In the embodiments of the present application, after obtaining the drop prediction result output by the above drop prediction model, it is possible to determine whether the electronic device will be in a drop state according to the drop prediction result; if the drop prediction result indicates that the electronic device will be in a drop state, then the feedback voltage signal of the speaker can be obtained and subsequent steps can be executed, so as to avoid damaging the power amplifier when the electronic device drops.

[0084] In some embodiments, the above-mentioned drop prediction result may include a drop probability, which is used to characterize the probability that the electronic device will be in a dropped state. According to the drop probability in the drop prediction result, the drop probability can be compared with a probability threshold. For example, the probability threshold can be 0.8, 0.85, 0.95, etc.; according to the comparison result, if the drop probability is greater than the probability threshold, then it can be determined that the electronic device will be in a dropped state, obtain the feedback voltage signal of the speaker, and perform subsequent steps

[0085] Step S440: Output an anti-phase signal to the speaker through the power amplifier, and the phase of the anti-phase signal is opposite to the phase of the feedback voltage signal.

[0086] In the embodiment of the present application, step S440 may refer to the content of the foregoing embodiment and will not be elaborated here.

[0087] The control method of the speaker provided by the embodiment of the present application can, when the electronic device drops, output an anti-phase signal to the speaker, so as to cancel the back electromotive force generated by the speaker during the drop process, and further avoid the return current generated by the back electromotive force from burning out the power amplifier, and realize the possibility of reducing the damage of the power amplifier due to the drop of the electronic device without adding new devices in the electronic device; in addition, by predicting whether the electronic device will be in a dropped state, an anti-phase signal can be output in real time when the electronic device is actually in the drop process, so as to better protect the power amplifier.

[0088] Next, through Figure 6 introduce the control method of the speaker involved in the foregoing embodiment.

[0089] As Figure 6 shown, the application processor can obtain the data collected by the motion sensor, and determine whether it is in a dropped state according to the data collected by the motion sensor; in the case of determining that it is in a dropped state, output an anti-phase signal to the power amplifier according to the feedback voltage signal, and the phase of the output anti-phase signal is opposite to the phase of the feedback voltage signal; after the power amplifier amplifies the anti-phase signal, output the amplified anti-phase signal to the speaker, so as to cancel the back electromotive force generated by the speaker during the drop process, and further avoid the return current generated by the back electromotive force from burning out the power amplifier.

[0090] Please refer to Figure 7, which shows a structural block diagram of a control device 500 of a speaker provided by an embodiment of the present application. The control device 500 of the speaker is applied to the above-mentioned electronic device. The control device 500 of the speaker includes: a signal acquisition module 510 and a signal output module 520. Among them, the signal acquisition module 510 is configured to acquire a feedback voltage signal of the speaker when the electronic device is in a falling state; the signal output module 520 is configured to output an anti-phase signal to the speaker through the power amplifier, and the phase of the anti-phase signal is opposite to the phase of the feedback voltage signal.

[0091] In some embodiments, the signal output module 520 may be specifically configured to: output a first anti-phase signal to the power amplifier, where the phase of the first anti-phase signal is opposite to the phase of the feedback voltage signal; output a second anti-phase signal obtained by amplifying the first anti-phase signal to the speaker through the power amplifier, and the amplitude of the second anti-phase signal matches the amplitude of the feedback voltage signal.

[0092] In a possible embodiment, the amplitude of the first anti-phase signal matches the amplitude of the feedback voltage signal. The signal output module 520 may be specifically configured to: amplify the first anti-phase signal through the power amplifier in a unity gain mode and output the amplified second anti-phase signal to the speaker.

[0093] In a possible embodiment, the signal output module 520 may be specifically configured to: amplify the first anti-phase signal through the power amplifier in a fixed gain mode and output the amplified second anti-phase signal to the speaker. The amplitude of the first anti-phase signal is determined according to the gain of the power amplifier and the amplitude of the feedback voltage signal, and the amplitude of the second anti-phase signal matches the amplitude of the feedback voltage signal.

[0094] In some embodiments, the signal output module 520 may be specifically configured to: continuously output an anti-phase signal to the speaker through the power amplifier during the process of the electronic device being in a falling state.

[0095] In a possible embodiment, the signal output module 520 may be specifically configured to: continuously output an anti-phase signal to the speaker through the power amplifier during the process of the electronic device being in a falling state, and adjust the amplitude of the anti-phase signal according to the falling speed of the electronic device when it is in a falling state.

[0096] Optionally, the signal output module 520 may be specifically configured to: adjust the amplitude of the anti-phase signal to the amplitude corresponding to the current duration according to the correspondence between the duration and the amplitude when the electronic device is in a falling state, where the correspondence is pre-determined according to the gravitational acceleration and Lenz's law.

[0097] In some embodiments, the signal acquisition module 510 may be specifically configured to: acquire the motion data collected by the motion sensor; if the motion data meets the target motion condition, determine that the electronic device is in a falling state.

[0098] In some embodiments, the signal acquisition module 510 may be specifically configured to: acquire the status data collected by the target sensor, where the target sensor includes at least one of a motion sensor, a barometer, and an ultrasonic sensor; input the status data into a pre-trained fall prediction model to obtain the fall prediction result output by the fall prediction model; if the fall prediction result indicates that the electronic device will be in a falling state, acquire the feedback voltage signal of the speaker.

[0099] Those skilled in the art can clearly understand that for the convenience and brevity of description, the specific working processes of the above-described devices and modules can refer to the corresponding processes in the foregoing method embodiments, and will not be elaborated herein.

[0100] In several embodiments provided in the present application, the coupling between modules may be electrical, mechanical, or other forms of coupling.

[0101] In addition, in each embodiment of the present application, the various functional modules may be integrated in one processing module, or each module may exist physically alone, or two or more modules may be integrated in one module. The above-mentioned integrated modules may be implemented in the form of hardware or in the form of software functional modules.

[0102] In summary, the solution provided in the present application, by acquiring the feedback voltage signal of the speaker when the electronic device is in a falling state, outputs an anti-phase signal to the speaker through a power amplifier, and the phase of the anti-phase signal is opposite to the phase of the feedback voltage signal. Thus, when the electronic device falls, by outputting an anti-phase signal to the speaker, the back electromotive force generated by the speaker during the falling process can be cancelled, thereby avoiding the backflow generated by the back electromotive force from burning out the power amplifier, and reducing the possibility of the power amplifier being damaged due to the fall of the electronic device.

[0103] Please refer to Figure 8, which shows a structural block diagram of an electronic device provided by an embodiment of the present application. The electronic device 100 may be an electronic device capable of running application programs such as a smart phone, a tablet computer, a smart watch, an e-book, etc. The electronic device 100 in the present application may include one or more of the following components: a processor 110, a memory 120, a power amplifier 103, a speaker 104, and one or more application programs, where one or more application programs may be stored in the memory 120 and configured to be executed by one or more processors 110, and one or more application programs are configured to execute the methods described in the foregoing method embodiments.

[0104] The processor 110 may include one or more processing cores. The processor 110 connects various parts within the entire electronic device 100 using various interfaces and lines. By running or executing instructions, programs, code sets, or instruction sets stored in the memory 120, and by calling data stored in the memory 120, the processor 110 executes various functions of the electronic device 100 and processes data. Optionally, the processor 110 may be implemented in at least one hardware form of an application processor, a digital signal processor, a Field-Programmable Gate Array (FPGA), or a Programmable Logic Array (PLA). The processor 110 may integrate a combination of one or several of a Central Processing Unit (CPU), a Graphics Processing Unit (GPU), and a modem, etc. Among them, the CPU mainly processes the operating system, user interface, application programs, etc.; the GPU is responsible for rendering and drawing the displayed content; the modem is used to process wireless communication. It can be understood that the above modem may not be integrated into the processor 110 and may be implemented separately by a communication chip.

[0105] The memory 120 may include a Random Access Memory (RAM), and may also include a Read-Only Memory. The memory 120 can be used to store instructions, programs, code, code sets, or instruction sets. The memory 120 may include a program storage area and a data storage area. Among them, the program storage area may store instructions for implementing the operating system, instructions for implementing at least one function (such as a touch function, a sound playback function, an image playback function, etc.), instructions for implementing the following various method embodiments, etc. The data storage area may also store data created during the use of the electronic device 100 (such as a phone book, audio and video data, chat record data, etc.).

[0106] Among them, when the processor 110 determines that the electronic device 100 is in a falling state, it can obtain the feedback voltage signal of the speaker 104, and then output an anti-phase signal to the speaker 104 through the power amplifier 103, and the phase of the anti-phase signal is opposite to the phase of the feedback voltage signal.

[0107] Please refer to Figure 9 , which shows a structural block diagram of a computer-readable storage medium provided by an embodiment of the present application. Program code is stored in the computer-readable medium 800, and the program code can be called by a processor to execute the method described in the above method embodiment.

[0108] The computer-readable storage medium 800 can be an electronic memory such as a flash memory, EEPROM (electrically erasable programmable read-only memory), EPROM, hard disk, or ROM. Optionally, the computer-readable storage medium 800 includes a non-transitory computer-readable storage medium. The computer-readable storage medium 800 has a storage space for the program code 810 that executes any method step in the above method. These program codes can be read from or written into one or more computer program products. The program code 810 can be compressed in an appropriate form, for example.

[0109] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A control method for a loudspeaker, characterized in that, Applied to an electronic device, the electronic device includes a speaker and a power amplifier, and the method includes: When the electronic device is in a falling state, obtain a feedback voltage signal of the speaker; Output an anti-phase signal to the speaker through the power amplifier, and the phase of the anti-phase signal is opposite to the phase of the feedback voltage signal.

2. The method according to claim 1, wherein The outputting an anti-phase signal to the speaker through the power amplifier includes: Output a first anti-phase signal to the power amplifier, and the phase of the first anti-phase signal is opposite to the phase of the feedback voltage signal; Output a second anti-phase signal amplified from the first anti-phase signal to the speaker through the power amplifier, and the amplitude of the second anti-phase signal matches the amplitude of the feedback voltage signal.

3. The method according to claim 2, wherein The amplitude of the first anti-phase signal matches the amplitude of the feedback voltage signal, and the outputting a second anti-phase signal amplified from the first anti-phase signal to the speaker through the power amplifier includes: Amplify the first anti-phase signal through the power amplifier in the unity gain mode and output the amplified second anti-phase signal to the speaker.

4. The method according to claim 2, wherein The outputting a second anti-phase signal amplified from the first anti-phase signal to the speaker through the power amplifier includes: Amplify the first anti-phase signal through the power amplifier in the fixed gain mode and output the amplified second anti-phase signal to the speaker. The amplitude of the first anti-phase signal is determined according to the gain of the power amplifier and the amplitude of the feedback voltage signal, and the amplitude of the second anti-phase signal matches the amplitude of the feedback voltage signal.

5. The method according to claim 1, characterized in that The outputting an anti-phase signal to the speaker through the power amplifier includes: During the process that the electronic device is in a falling state, continuously output an anti-phase signal to the speaker through the power amplifier.

6. The method according to claim 5, characterized in that, The continuously outputting an anti-phase signal to the speaker through the power amplifier during the process that the electronic device is in a falling state includes: During the process that the electronic device is in a falling state, continuously output an anti-phase signal to the speaker through the power amplifier, and adjust the amplitude of the anti-phase signal according to the falling speed when the electronic device is in a falling state.

7. The method according to claim 6, wherein The adjusting the amplitude of the anti-phase signal according to the falling speed when the electronic device is in a falling state includes: Adjust the amplitude of the anti-phase signal to the amplitude corresponding to the current duration according to the corresponding relationship between the duration and the amplitude when the electronic device is in a falling state, and the corresponding relationship is pre-determined according to the gravitational acceleration and Lenz's law.

8. The method according to any one of claims 1 to 7, characterized in that, The obtaining a feedback voltage signal of the speaker when the electronic device is in a falling state includes: Obtain the motion data collected by the motion sensor; If the motion data meets the target motion condition, determine that the electronic device is in a falling state.

9. The method according to any one of claims 1-7, characterized in that, The obtaining a feedback voltage signal of the speaker when the electronic device is in a falling state includes: Obtain the status data collected by the target sensor, where the target sensor includes at least one of a motion sensor, a barometer, and an ultrasonic sensor; Input the status data into a pre-trained drop prediction model to obtain the drop prediction result output by the drop prediction model; If the drop prediction result indicates that the electronic device will be in a dropped state, obtain the feedback voltage signal of the speaker.

10. A control device for a speaker, characterized in that, Applied to an electronic device, the electronic device includes a speaker and a power amplifier, and the apparatus includes: a signal acquisition module and a signal output module, where, The signal acquisition module is configured to obtain the feedback voltage signal of the speaker when the electronic device is in a dropped state; The signal output module is configured to output an anti-phase signal to the speaker through the power amplifier, and the phase of the anti-phase signal is opposite to the phase of the feedback voltage signal.

11. An electronic device, characterized in that, Comprising: One or more processors; A memory; One or more programs, where the one or more programs are stored in the memory and configured to be executed by the one or more processors, and the one or more programs are configured to execute the method according to any one of claims 1-9.

12. A computer-readable storage medium, characterized in that, Program code is stored in the computer-readable storage medium, and the program code can be called by the processor to execute the method according to any one of claims 1-9.

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