Audio control circuit, audio processing method and terminal device

Abstract

This application discloses an audio control circuit, an audio processing method, and a terminal device, belonging to the field of audio processing technology. The audio control circuit includes a processing module, an audio bus, a first power amplifier module, and a second power amplifier module. The output terminal of the processing module is connected to the input terminal of the second power amplifier module via the audio bus, and the feedback output terminal of the second power amplifier module is connected to the input terminal of the processing module. The output terminal of the processing module is also connected to the input terminal of the first power amplifier module via the audio bus. The processing module is used to send an ultrasonic signal to the second power amplifier module, so that the second power amplifier module can generate an interference signal based on the ultrasonic signal and transmit it to the processing module. The processing module is also used to generate a cancellation signal based on the interference signal, and mix the cancellation signal, the ultrasonic signal, and the audio signal into a mixed audio signal before sending it to the first power amplifier module.

Description

Technical Field

[0001] This application belongs to the field of audio processing technology, specifically relating to an audio control circuit, an audio processing method, and a terminal device. Background Technology

[0002] Mobile phone proximity sensors often employ ultrasonic detection, which involves the earpiece emitting an ultrasonic signal and the microphone receiving the signal reflected from the ear. The phone determines its distance from the listener's ear based on the frequency difference between the transmitted and received signals.

[0003] Both the ultrasonic sweep signal and the service audio signal need to be output to the earpiece through the mobile phone's smart amplifier. The ultrasonic signal is used for proximity sensing, and the service audio signal is used for call playback. However, the nonlinear response of the smart amplifier and its output link may cause intermodulation distortion in the ultrasonic signal and create interference signals in the audible frequency band, thus affecting the call quality of the service audio signal. To address this issue, existing technologies typically reduce audible noise generated by the ultrasonic signal after passing through the smart amplifier by adjusting the ultrasonic transmission frequency band, reducing the ultrasonic signal transmission amplitude, or adjusting the ultrasonic signal sweep method.

[0004] However, the above method mainly relies on adjusting the ultrasonic emission parameters, and its effect on suppressing audible noise is easily affected by differences in terminal hardware, the degree of nonlinearity of the power amplifier, etc., which makes it difficult to effectively suppress the audible noise generated by the ultrasonic signal after passing through the intelligent power amplifier. Summary of the Invention

[0005] This application aims to provide an audio control circuit, an audio processing method, and a terminal device that can solve the problem that audible noise generated by ultrasonic signals after passing through an intelligent power amplifier is difficult to suppress effectively.

[0006] In a first aspect, embodiments of this application propose an audio control circuit, including: a processing module, an audio bus, a first power amplifier module, and a second power amplifier module; The output of the processing module is connected to the input of the second power amplifier module via an audio bus. The feedback output of the second power amplifier module is connected to the input of the processing module. The output of the processing module is also connected to the input of the first power amplifier module via an audio bus. The processing module is used to send the ultrasonic signal to the second power amplification module, so that the second power amplification module can generate an interference signal based on the ultrasonic signal and transmit it to the processing module; The processing module is also used to generate a cancellation signal based on the interference signal, and to mix the cancellation signal, ultrasonic signal and audio signal into a mixed audio signal before sending it to the first power amplification module.

[0007] Secondly, this application provides an audio processing method applied to the processing module of the audio control circuit, comprising: sending an ultrasonic signal to a second power amplification module via an audio bus, so that the second power amplification module generates an interference signal based on the ultrasonic signal; It receives the interference signal transmitted by the second power amplifier module and generates a cancellation signal based on the interference signal; The cancellation signal, ultrasonic signal, and audio signal are mixed into a mixed audio signal; The mixed audio signal is sent to the first power amplifier module via the audio bus, so that the first power amplifier module can perform audio driving based on the mixed audio signal; The cancellation signal is used to cancel the interference signal generated after the ultrasonic signal is processed by the first power amplification module.

[0008] Thirdly, embodiments of this application propose a terminal device, including an audio control circuit of the first aspect, which executes the audio processing method of the second aspect.

[0009] In the embodiments of this application, the processing module sends an ultrasonic signal to the second power amplification module before the service audio signal is output. After receiving the ultrasonic signal, the second power amplification module performs driving processing based on the ultrasonic signal to generate an interference signal, which is then sent to the processing module. The processing module generates a cancellation signal based on the interference signal, providing a basis for subsequently canceling the ultrasonic interference in the first power amplification module. When the service audio signal is output, the processing module mixes the cancellation signal, the ultrasonic signal, and the service audio signal into a mixed audio signal, which is then sent to the first power amplification module. When the first power amplification module performs driving processing based on the mixed audio signal, the interference signal formed by the ultrasonic signal after processing by the first power amplification module can be correspondingly canceled by the cancellation signal, thereby preventing the interference signal from being superimposed on the service audio signal before output. Therefore, compared to methods that reduce noise by simply adjusting the ultrasonic transmission frequency band, reducing the ultrasonic transmission amplitude, or changing the frequency sweep method, this application can generate a cancellation signal based on the interference signal fed back by the second power amplification module, thereby suppressing the interference formed after the ultrasonic signal is processed by the first power amplification module. Since the cancellation signal is generated based on the currently fed-back interference signal, rather than relying solely on the preset ultrasonic transmission frequency band, transmission amplitude, or frequency sweep method, it can address the interference differences caused by differences in different terminal hardware and power amplifier nonlinearity, thereby alleviating the problem that audible noise is difficult to suppress effectively and reducing the impact of ultrasonic signals on the listening experience of service audio in handset call scenarios. Thus, this application can cancel the audible interference generated by the ultrasonic signal through the audio drive link while retaining the ultrasonic signal for distance detection function, enabling the terminal to simultaneously achieve ultrasonic detection function and service audio output quality.

[0010] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0011] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0012] Figure 1 This is a schematic diagram illustrating the use of ultrasonic signals to achieve mobile phone proximity sensing functionality, provided in an embodiment of this application. Figure 2 This is a schematic diagram of the mobile phone hardware path for an ultrasonic solution provided in an embodiment of this application; Figure 3 This is a schematic diagram of intermodulation distortion of an ultrasonic signal provided in an embodiment of this application; Figure 4 This is a schematic diagram of the structure of an audio control circuit provided in an embodiment of this application; Figure 5 This is a schematic diagram of the specific structure of an audio control circuit provided in an embodiment of this application; Figure 6 This is a schematic diagram of another structure of an audio control circuit provided in an embodiment of this application; Figure 7 This is a flowchart of an audio processing method provided in an embodiment of this application; Figure 8 This is a timing diagram of an audio processing method provided in an embodiment of this application; Figure 9 This is a block diagram of a terminal device provided in an embodiment of this application; Figure 10 This is a schematic diagram of the hardware structure of a terminal device provided in an embodiment of this application. Detailed Implementation

[0013] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0014] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0015] The term "connection" used in the embodiments of this application should be interpreted broadly. For example, it can refer to a physical direct connection or an indirect connection implemented through electronic devices, such as a connection implemented through resistors, inductors, capacitors or other electronic devices.

[0016] In mobile phone design, ultrasonic detection is often used to achieve proximity sensing, thereby determining whether the user's phone is close to the ear area. For example... Figure 1 As shown, the mobile phone uses a multiplexed earpiece to transmit ultrasonic signals, while simultaneously receiving the echo signals reflected from the ear via a top or front-facing microphone; specifically, as... Figure 2 As shown, the ultrasonic transmitted and received signals are processed by the ultrasonic algorithm in the audio DSP (Digital Signal Processor). After processing by the audio algorithm, the audio signal is superimposed by the audio mixer and output to the earpiece by power amplifier 1 (upper speaker amplifier). The audio DSP calculates the round-trip propagation time of the sound wave based on the frequency difference between the transmitted and received signals, thereby determining the distance between the phone and the user's ear area. This determines whether the phone is close to the user's ear, enabling functions such as screen on / off during calls or other distance-based control. Simultaneously, the user's audio signal is input through the microphone, processed by the codec and audio DSP, and then driven by power amplifiers 1 and 2 (lower speaker amplifiers) to output to the upper and lower speakers respectively, enabling normal call or media playback functions. In this way, the phone can accurately detect user proximity without additional sensors, ensuring normal audio signal output while performing distance detection.

[0017] During the proximity sensing process in a mobile phone, the ultrasonic signal needs to be amplified by the phone's smart amplifier before being output to the earpiece, and then the earpiece emits ultrasonic signals of the corresponding frequency band. Because the smart amplifier is a non-ideal linear system, nonlinear responses may be introduced during the amplification, modulation, or differential drive output of the ultrasonic signal. This nonlinear response can cause intermodulation distortion of the ultrasonic signal, which is originally outside the audible frequency range, thus creating interference signals within the audible frequency range. For example... Figure 3As shown, the two original ultrasonic signals in the spectrum are located in the frequency bands f1 and f2, which are greater than 20 kHz. However, the intermodulation distortion signal generated by the nonlinear response falls into the audible frequency bands f2-f1 and 2f1-f2, which are less than 20 kHz, constituting the demodulated in-band interference signal. In the scenario of ear-to-ear communication, the distance between the earpiece and the ear is relatively close, and the audible frequency interference signal output by the earpiece is not easily attenuated, making it easy for the user to perceive as noise or background noise, thus affecting the listening experience during the call.

[0018] To overcome the above problems, this application provides an audio control circuit and an audio processing method. The second power amplification module collects and processes ultrasonic signals to generate interference signals, and feeds the interference signals back to the processing module. The processing module generates corresponding cancellation signals, and then mixes the cancellation signals with the original ultrasonic signals and the service audio signals for output. This effectively suppresses audible interference generated by the ultrasonic signals after processing by the power amplification module, improves the earpiece call quality, and ensures the stability and reliability of the mobile phone's proximity sensing function.

[0019] Figure 4 This is a schematic diagram of an audio control circuit provided in an embodiment of this application, such as... Figure 4 As shown, the audio control circuit may include: a processing module 100, an audio bus 200, a first power amplifier module 300, and a second power amplifier module 400; The output of the processing module 100 is connected to the input of the second power amplifier module 400 via the audio bus 200. The feedback output of the second power amplifier module 400 is connected to the input of the processing module 100. The output of the processing module 100 is also connected to the input of the first power amplifier module 300 via the audio bus 200. The processing module 100 is used to send the ultrasonic signal to the second power amplification module 400, so that the second power amplification module 400 can generate an interference signal based on the ultrasonic signal and transmit it to the processing module 100. The processing module 100 is also used to generate a cancellation signal based on the interference signal, and to mix the cancellation signal, the ultrasonic signal and the audio signal into a mixed audio signal before sending it to the first power amplification module 300.

[0020] In some embodiments, the audio control circuit is disposed in the terminal device and is used to perform a combination of functions including audio signal transmission, drive output, and feedback processing. The audio control circuit can be applied to terminal devices with acoustic output and ultrasonic detection functions, such as mobile phones, tablets, and wearable devices. Taking a mobile phone as an example, the audio control circuit can be used in the earpiece call scenario. In this scenario, the mobile phone needs to output call audio through the earpiece on the one hand, and can also reuse the earpiece to emit ultrasonic signals to perform distance detection near the human ear area on the other hand.

[0021] In some embodiments, the processing module 100 is a control or arithmetic unit for generating, receiving, buffering and processing audio-related data; the processing module 100 may be an application processor (AP), an audio processing chip, or an audio processing module integrated into a system chip.

[0022] In some embodiments, the audio bus 200 is a bus for transmitting digital audio data between the processing module 100 and the power amplifier module; the audio bus 200 can be an integrated circuit audio (Inter-IC Sound, I2S) bus, a time division multiplexing (TDM) bus that supports multi-channel transmission, or other digital audio buses capable of transmitting audio data and channel selection information.

[0023] In some embodiments, the first power amplifier module 300 is a drive circuit or drive chip for receiving the mixed audio signal sent by the processing module 100 and driving the audio signal; the first power amplifier module 300 can be an upamping amplifier, a smart audio amplifier, or other audio drivers for driving the acoustic output unit.

[0024] In some embodiments, the second power amplifier module 400 is a drive circuit or drive chip for receiving ultrasonic signals sent by the processing module 100 and forming feedback; the second power amplifier module 400 can be a downamp amplifier, a smart audio amplifier, or other audio drivers with feedback acquisition capabilities.

[0025] In some embodiments, the interference signal is a signal generated after the ultrasonic signal is processed by the second power amplification module 400, which can characterize the interference components generated after the ultrasonic signal is processed by the drive link; the cancellation signal is a signal generated by the processing module 100 based on the interference signal, which is used to cancel the interference signal generated by the ultrasonic signal after it is processed by the first power amplification module 300; the mixed audio signal is a signal formed by mixing the cancellation signal, the ultrasonic signal and the audio signal, and after the mixed audio signal is sent to the first power amplification module 300, it is driven by the first power amplification module 300 for audio.

[0026] For example, such as Figure 5As shown, taking a mobile phone as an example, after the earpiece mode is started, the AP can send an ultrasonic signal to the speaker amplifier through one channel of the audio bus 200. The ultrasonic signal can be an ultrasonic sweep signal for distance detection or a preset ultrasonic pulse sequence. After receiving the ultrasonic signal, the speaker amplifier performs driving processing on the ultrasonic signal and forms a differential driving signal corresponding to the ultrasonic signal at its output end. Since the speaker amplifier and its output link may have nonlinear response, the ultrasonic signal may form interference components that fall into the audible frequency band after driving processing.

[0027] The current and voltage sense analog-to-digital converter (IV sense ADC) in the speaker amplifier acquires feedback information from the differential drive signal and generates an interference signal based on this feedback information. The feedback information can include voltage feedback, current feedback, or both. The speaker amplifier transmits the interference signal to the access point (AP) through its feedback output, enabling the AP to obtain the interference characteristics formed by the ultrasonic signal processed by the speaker amplifier in the current terminal.

[0028] The AP can reverse the phase of the interference signal to obtain a cancellation signal with the opposite phase to the interference signal; it can also reverse the sampled values ​​in the interference signal one by one so that the sampled values ​​in the cancellation signal have the opposite polarity to the corresponding sampled values ​​in the interference signal; the AP mixes the cancellation signal, the ultrasonic signal and the audio signal with the same data block length to obtain a mixed audio signal.

[0029] The AP sends the mixed audio signal to the upspeaker amplifier via another channel in the audio bus 200. After receiving the mixed audio signal, the upspeaker amplifier performs audio drive processing on the mixed audio signal and drives the corresponding acoustic output unit to output sound. Since the mixed audio signal contains a cancellation signal, when the ultrasonic signal forms an interference signal after being processed by the upspeaker amplifier, the cancellation signal can cancel out the interference signal, thereby reducing the impact of the ultrasonic signal on the listening experience of the audio signal.

[0030] For example, before the audio signal is officially output, the processing module 100 sends a reference audio signal to the channel data position corresponding to the first power amplification module 300, and sends a reference audio signal and an ultrasonic signal to the channel data position corresponding to the second power amplification module 400. The reference audio signal can be a mute signal or zero-value audio data; the reference audio signal sent to the first power amplification module 300 is used to occupy the channel data position corresponding to the first power amplification module 300, preventing the first power amplification module 300 from receiving the ultrasonic signal used for distance detection before the audio signal is sent; the reference audio signal sent to the second power amplification module 400 is used as a mute placeholder before the audio signal is output.

[0031] For example, after the audio signal is officially output, the processing module 100 sends a mixed audio signal to the first power amplifier module 300 via the audio bus 200. The mixed audio signal includes a service audio signal, an ultrasonic signal, and a cancellation signal. At this time, the second power amplifier module 400 only outputs a mute signal for the corresponding channel and no longer emits ultrasonic signals, thereby avoiding additional audible interference.

[0032] In summary, before the service audio signal is output, the processing module sends an ultrasonic signal to the second power amplification module. Upon receiving the ultrasonic signal, the second power amplification module performs driving processing to generate an interference signal, which is then sent to the processing module. The processing module generates a cancellation signal based on the interference signal, providing a basis for subsequently canceling the ultrasonic interference in the first power amplification module. When the service audio signal is output, the processing module mixes the cancellation signal, the ultrasonic signal, and the service audio signal into a mixed audio signal, which is then sent to the first power amplification module. When the first power amplification module performs driving processing based on the mixed audio signal, the interference signal formed after the ultrasonic signal is processed by the first power amplification module can be correspondingly canceled by the cancellation signal, thereby preventing the interference signal from being superimposed on the service audio signal before output. Therefore, compared to methods that reduce noise by simply adjusting the ultrasonic transmission frequency band, reducing the ultrasonic transmission amplitude, or changing the frequency sweep method, this application can generate a cancellation signal based on the interference signal fed back by the second power amplification module, thereby suppressing the interference formed by the ultrasonic signal after passing through the first power amplification module. Since the cancellation signal is generated based on the currently fed-back interference signal, rather than relying solely on the preset ultrasonic transmission frequency band, transmission amplitude, or frequency sweep method, it can address the interference differences caused by differences in different terminal hardware and power amplifier nonlinearity, thereby alleviating the problem that audible noise is difficult to suppress effectively and reducing the impact of ultrasonic signals on the listening experience of business audio in handset call scenarios.

[0033] Optional, such as Figure 5 As shown, the audio bus 200 includes a select signal line 201, a transmission signal line 202, and a clock signal line 203; The transmission signal line 202 is used to transmit ultrasonic signals and mixed audio signals; the selection signal line 201 is used to control the transmission of ultrasonic signals to the second power amplifier module 400 and the transmission of mixed audio signals to the first power amplifier module 300; the clock signal line 203 is used to provide a read clock, so that the second power amplifier module 400 receives the corresponding ultrasonic signal based on the read clock, and the first power amplifier module 300 receives the corresponding mixed audio signal based on the read clock.

[0034] In this embodiment, the selection signal line 201 is used to distinguish data received by different channels or control different power amplifier modules on the audio bus 200. It can be a word select (WS) signal line or a left / right clock (LRCLK) signal line. The selection signal line 201 controls the data on the transmission signal line 202 to be received by the first power amplifier module 300 or the second power amplifier module 400 through different level states or different selection states. The transmission signal line 202 is used to transmit actual audio data and can be a data input (DATA_IN) signal line. The clock signal line 203 is used to provide data reading time, so that each power amplifier module receives the corresponding data in the same timing sequence. It can be a serial clock (SCLK) signal line or a serial data (SD) signal line.

[0035] For example, such as Figure 5 As shown, the audio bus 200 is an I2S bus, the select signal line 201 is the WS signal line, the transmission signal line 202 is the DATA_IN signal line, and the clock signal line 203 is the SCLK signal line. The processing module 100 transmits ultrasonic signals or mixed audio signals through the DATA_IN signal line, distinguishes between data transmitted to the first power amplifier module 300 and data transmitted to the second power amplifier module 400 through the WS signal line, and provides a data reading clock through the SCLK signal line.

[0036] By setting selection signal lines, transmission signal lines, and clock signal lines on the audio bus, the processing module can accurately transmit ultrasonic signals to the second power amplifier module to generate interference signals, while simultaneously transmitting mixed audio signals to the first power amplifier module for audio driving. The transmission signal lines can carry both ultrasonic signals and mixed audio signals, simplifying the hardware structure. The clock signal line provides a read clock, enabling the first and second power amplifier modules to receive data at the same pace, ensuring data synchronization and accurate channel transmission. This provides a reliable foundation for stable operation of cancellation signal generation, ultrasonic interference suppression, and audio output.

[0037] Optional, such as Figure 6As shown, both the first power amplification module 300 and the second power amplification module 400 include: a first processing unit and a data acquisition and feedback unit; The input terminal of the first processing unit is connected to the output terminal of the processing module 100, and is used to receive ultrasonic signals or mixed audio signals and generate corresponding differential drive signals. The input terminal of the data acquisition and feedback unit is connected to the output terminal of the first processing unit, and the feedback output terminal of the data acquisition and feedback unit is connected to the input terminal of the processing module 100. The acquisition feedback unit 302 of the first power amplifier module 300 is used to acquire feedback information of the differential drive signal corresponding to the mixed audio signal, generate data based on the feedback information to determine the output state of the first power amplifier module 300, and send it to the processing module 100. The acquisition feedback unit 402 of the second power amplification module 400 is used to acquire feedback information of the differential drive signal corresponding to the ultrasonic signal, generate an interference signal based on the feedback information, and send it to the processing module 100; the interference signal is the interference component formed after the ultrasonic signal is processed by the first processing unit.

[0038] In this embodiment, the first processing unit is responsible for forming a differential driving signal between the ultrasonic signal or mixed audio signal output by the processing module 100 and the driving output terminals OUT_P and OUT_N; the acquisition feedback unit is responsible for acquiring the voltage and current feedback corresponding to the differential driving signal and returning the feedback information to the processing module 100.

[0039] For example, the first power amplifier module 300 can be a power amplifier for speakers, a power amplifier for handsets, or a smart amplifier, and the second power amplifier module 400 can be a power amplifier for speakers, a power amplifier for external speakers, or a smart amplifier; both can include a first processing unit and a data acquisition and feedback unit. Specifically, the first processing unit 301 of the first power amplifier module 300 is used to drive the received mixed audio signal to generate a differential drive signal; the first processing unit 401 of the second power amplifier module 400 is used to drive the received mixed audio signal to generate a differential drive signal; the data acquisition and feedback unit can be an IV Sense ADC module, used to acquire feedback information corresponding to the differential drive signal; the feedback information can include voltage feedback information or current feedback information.

[0040] For example, such as Figure 5As shown, the acquisition feedback units in both the first power amplifier module 300 and the second power amplifier module 400 can be connected to the processing module 100 via feedback data lines. The feedback data line of the first power amplifier module 300 can be an up-output (DATA_OUT_UP) signal line 204, and the feedback data line of the second power amplifier module 400 can be a down-output (DATA_OUT_DOWN) signal line 205. Through the above connection method, the processing module 100 can obtain the output status data of the first power amplifier module 300, which can be used to characterize the output amplitude, output voltage, current status, or load status of the first power amplifier module 300. The processing module 100 can also obtain the interference signal generated by the second power amplifier module 400 based on the ultrasonic signal and generate a cancellation signal based on the interference signal.

[0041] By setting up acquisition feedback units in both the first and second power amplification modules, the processing module can acquire feedback information of the differential drive signal in real time, thereby generating interference signals and cancellation signals, and effectively suppressing audible interference generated by the ultrasonic signal.

[0042] Optionally, the first processing unit includes: a receiving port and a first processing subunit; The input terminal of the first processing subunit is connected to the output terminal of the processing module 100 through the receiving port, and is used to receive ultrasonic signals or mixed audio signals through the receiving port; The output of the first processing subunit is connected to the input of the acquisition feedback unit; it is used to modulate and amplify ultrasonic signals or mixed audio signals, generate differential drive signals, and send them to the acquisition feedback unit.

[0043] In this embodiment of the application, the receiving port is used to receive the ultrasonic signal or mixed audio signal output by the processing module 100 and transmit it to the first processing subunit; the first processing subunit modulates and amplifies the received signal to generate a differential driving signal and transmits it to the acquisition feedback unit; the differential driving signal is a pulse width modulation power signal with alternating high and low levels, used to drive acoustic output units, such as earpieces and speakers.

[0044] For example, such as Figure 5 As shown, the receiving port can be either an I2S interface or a TDM interface; both the I2S interface and the TDM interface are used to receive data sent by the processing module 100 according to the corresponding audio transmission protocol, and transmit the received data to the first processing subunit.

[0045] By combining the receiving port with the first processing subunit to form the first processing unit, the differential drive signal can be accurately generated, thereby ensuring the correct processing of ultrasonic signals and mixed audio signals.

[0046] Optional, such as Figure 6 As shown, the processing module 100 includes: a storage unit 101, a transmitter 102, and a second processing unit 103; The input terminal of the storage unit 101 is connected to the feedback output terminal of the second power amplifier module 400 for storing interference signals; The second processing unit 103 includes a cancellation signal generation unit 1031 and a mixing processing unit 1032; the input terminal of the cancellation signal generation unit 1031 is connected to the output terminal of the storage unit 101, and is used to generate a cancellation signal based on the interference signal; The input terminal of the mixing processing unit 1032 is connected to the output terminal of the cancellation signal generation unit 1031, and is used to receive the cancellation signal and mix the cancellation signal, the ultrasonic signal and the audio signal into a mixed audio signal; The input terminal of transmitter 102 is connected to the output terminal of mixing processing unit 1032, and the output terminal of transmitter 102 is connected to first power amplifier module 300, for sending mixed audio signals to first power amplifier module 300.

[0047] In this embodiment, the storage unit 101 is a storage structure in the processing module 100 used for caching or saving data, and it may include a data receiving buffer for receiving interference signals; the data receiving buffer may be configured as multiple circular buffers.

[0048] The cancellation signal generation unit 1031 is an operational structure used to generate a cancellation signal based on the interference signal; it can generate a cancellation signal by reverse processing of each sampling point or by phase reversal processing.

[0049] The hybrid processing unit 1032 is a processing structure used to combine multiple signals into one output signal; it can superimpose cancellation signals, ultrasonic signals and audio signals according to sampling points, or it can mix them according to the data block length; the audio signal can be a downlink voice signal for a call, or a service audio signal such as a prompt tone or voice playback signal.

[0050] Transmitter 102 is a transmission structure used to send mixed audio signals to the first power amplifier module 300; transmitter 102 can be an I2S transmitter or a TDM transmitter; transmitter 102 can send mixed audio signals to the first power amplifier module 300 through audio bus 200, or send ultrasonic signals to the second power amplifier module 400 before sending the service audio signal.

[0051] For example, the storage unit 101 may include multiple data receiving buffers; when an interference signal is received, the interference signal can be written into a data receiving buffer first; when the data receiving buffer is full, the system switches to the next data receiving buffer to continue receiving subsequent interference signals, while processing the interference signals in the already full data receiving buffer; multiple data receiving buffers can be used in a preset order to enable the reception of interference signals and the generation of subsequent cancellation signals to proceed continuously.

[0052] For example, the input terminal of the cancellation signal generation unit 1031 is connected to the output terminal of the storage unit 101, and is used to read the interference signal from the storage unit 101 and generate a cancellation signal based on the interference signal. The cancellation signal generation unit 1031 can divide the interference signal in a data receiving buffer into multiple processing blocks, and then perform phase inversion processing on the multiple processing blocks to obtain multiple cancellation blocks. Alternatively, it can perform sample point-by-sample inversion processing on the sampled values ​​in the interference signal so that the polarity of the sampled values ​​in the cancellation signal is opposite to that of the corresponding sampled values ​​in the interference signal.

[0053] For example, the input terminal of the mixing processing unit 1032 is connected to the output terminal of the cancellation signal generation unit 1031 to receive the cancellation signal; the mixing processing unit 1032 can also obtain ultrasonic signals and audio signals from the processing module 100 and mix the cancellation signal, ultrasonic signal and audio signal into a mixed audio signal; specifically, the mixing processing unit 1032 can mix the cancellation signal, ultrasonic signal and audio signal at the same sampling rate, or it can divide the ultrasonic signal and audio signal into ultrasonic signal blocks and audio signal blocks that correspond one-to-one with multiple cancellation blocks and have the same data length, and then mix the corresponding cancellation blocks, ultrasonic signal blocks and audio signal blocks into a mixed audio block, and then synthesize a mixed audio signal.

[0054] For example, after the mixing processing unit 1032 generates the mixed audio signal, the transmitter 102 sends the mixed audio signal to the first power amplifier module 300 through the audio bus 200. After receiving the mixed audio signal, the first power amplifier module 300 performs audio driving, so that the sound corresponding to the audio signal is output through the acoustic output structure. At the same time, the cancellation signal in the mixed audio signal is used to cancel the interference signal formed by the ultrasonic signal after being processed by the first power amplifier module 300.

[0055] In the above process, the storage unit first buffers the interference signal fed back by the second power amplification module, enabling the processing module to obtain interference data corresponding to the current ultrasonic signal. The cancellation signal generation unit generates a cancellation signal based on the buffered interference signal, making the cancellation signal correspond to the interference component formed after the ultrasonic signal is driven and processed. The mixing processing unit then mixes the cancellation signal, ultrasonic signal, and audio signal into a mixed audio signal, so that the first power amplification module can suppress the interference generated by the ultrasonic signal using the cancellation signal while outputting the service audio and ultrasonic signals. The transmitter sends the mixed audio signal to the first power amplification module, ensuring that the mixed signal can enter the actual audio drive link. Thus, while maintaining the ultrasonic detection function, the impact of the ultrasonic signal processed by the first power amplification module on the audible sound of the audio signal can be reduced.

[0056] Optional, such as Figure 6 As shown, the audio control circuit also includes: a first sound-generating module 500, a second sound-generating module 600, and a path control sub-circuit 700; The drive output terminal of the first power amplifier module 300 is connected to the first sound module 500 and is used to drive the first sound module 500 to output the sound corresponding to the mixed audio signal. The drive output terminal of the second power amplifier module 400 is connected to the second sound generation module 600 through the path control sub-circuit 700; the path control sub-circuit 700 is used to disconnect the output path between the second power amplifier module 400 and the second sound generation module 600 so that the second power amplifier module 400 stops driving the second sound generation module 600 to output sound when an interference signal is generated based on the ultrasonic signal.

[0057] In this embodiment, the first sound-generating module 500 is an acoustic device driven by the first power amplifier module 300 and used to output sound. It can be an earpiece or an upper speaker. In a mobile phone earpiece call scenario, the first sound-generating module 500 can be set in the top area of ​​the terminal and used to output the sound corresponding to the call audio to the user's ear.

[0058] The second sound module 600 is an acoustic device driven by the second power amplifier module 400 in a set working mode. It can be a lower speaker or an external speaker. In the mobile phone external speaker scenario, the second sound module 600 can be used to output external sound. In the earpiece mode, the second sound module 600 can be in a non-working state.

[0059] The path control sub-circuit 700 is a circuit structure disposed between the second power amplifier module 400 and the second sound generation module 600 for controlling the on / off state of the output path between the two. It may include a switching device or an on / off control circuit composed of a switching transistor and a control circuit. The switching device may be a metal-oxide-semiconductor field-effect transistor (MOS), and the control circuit may include a bootstrap circuit or a gate drive circuit for controlling the MOS transistor to turn on or off.

[0060] In this embodiment of the application, when the call is in earpiece mode, the second power amplifier module 400 can participate in the formation and feedback of the interference signal corresponding to the ultrasonic signal, but the second sound module 600 does not output sound.

[0061] Specifically, in earpiece mode, processing module 100 can still send ultrasonic signals to second power amplifier module 400. Second power amplifier module 400 generates interference signals based on ultrasonic signals and feeds them back to processing module 100. However, since the output path is disconnected by path control sub-circuit 700, second power amplifier module 400 will not drive second sound module 600 to output sound. In speakerphone mode, path control sub-circuit 700 can connect the output path between second power amplifier module 400 and second sound module 600, enabling second power amplifier module 400 to drive second sound module 600 to output sound. Thus, second power amplifier module 400 can drive second sound module 600 to output sound in speakerphone mode, and can also participate in the formation of interference signals corresponding to ultrasonic signals in earpiece mode without causing second sound module 600 to output sound.

[0062] In the above process, the first power amplifier module is connected to the first sound-generating module, enabling the mixed audio signal to be output through the first sound-generating module. The second power amplifier module is connected to the second sound-generating module through a path control sub-circuit, ensuring that when the second power amplifier module generates an interference signal based on the ultrasonic signal and feeds it back to the processing module, it does not drive the second sound-generating module to output sound. Therefore, in scenarios where the second sound-generating module is not working, such as in earpiece mode, the second power amplifier module can be reused to participate in the acquisition of ultrasonic interference characteristics, and unwanted sound output from the second sound-generating module can be avoided, thus ensuring that the subsequent cancellation signal generation process coordinates with the audio output process of the first sound-generating module.

[0063] Optional, such as Figure 5 As shown, the path control sub-circuit 700 includes: a first switching transistor, a second switching transistor, and a conduction control sub-unit; the processing module 100 includes a signal output terminal; The first terminal of the first switching transistor is connected to the drive output terminal of the second power amplifier module 400, and the second terminal of the first switching transistor is connected to the second sound generation module 600. The first terminal of the second switch is connected to the control terminal of the first switch, and the second terminal of the second switch is grounded. The control terminal and signal output terminal of the second switch are connected to receive the control signal sent by the processing module 100. In the event that the second power amplifier module 400 generates an interference signal based on the ultrasonic signal, the control terminal of the first switch is pulled low, causing the first switch to turn off, thereby disconnecting the output path. The conduction control subunit is connected to the control terminal of the first switching transistor to control the first switching transistor to conduct when the second power amplifier module 400 drives the second sound module 600 to output sound, thereby opening the output path.

[0064] In this embodiment, the first switching transistor is a switching device connected between the drive output terminal of the second power amplifier module 400 and the second sound generation module 600. It can be a MOS transistor or an analog switching device. The control terminal of the first switching transistor is used to receive the turn-on control voltage or the turn-off control signal.

[0065] The second switch is a switching device used to control the first switch to turn off. It can be a MOSFET, a transistor, or other controllable pull-down device. In one configuration, the first terminal of the second switch is connected to the control terminal of the first switch, and the second terminal of the second switch is grounded. The control terminal of the second switch receives the control signal output by the processing module 100. When the second switch is turned on, the control terminal of the first switch is pulled low, causing the first switch to turn off.

[0066] The conduction control subunit is a circuit structure used to control the conduction of the first switch. The conduction control subunit can be a gate drive circuit or a bootstrap circuit. The gate drive circuit is used to provide the control voltage required for conduction to the control terminal of the first switch. The bootstrap circuit is used to maintain the control terminal voltage of the first switch when the voltage of the drive output terminal of the second power amplifier module 400 changes, so that the first switch remains on.

[0067] In this embodiment of the application, in the external playback mode or speaker playback mode, the processing module 100 sends an audio signal to the second power amplifier module 400. After the audio signal is processed by the second power amplifier module 400, it drives the second sound-generating module 600 to output sound. At this time, the output path between the second power amplifier module 400 and the second sound-generating module 600 needs to be kept connected.

[0068] For example, when the mobile phone is in external speaker mode or speaker playback mode, the second sound module 600 needs to output sound. At this time, the processing module 100 may not output a control signal to the control terminal of the second switch to turn on the second switch. The second switch is in the off state, and the control terminal of the first switch will not be pulled low by the second switch. The conduction control subunit is connected to the control terminal of the first switch and maintains the conduction control voltage of the first switch, so that the first switch is in the conduction state. After the first switch is turned on, the output path between the drive output terminal of the second power amplifier module 400 and the second sound module 600 is connected. The differential drive signal output by the second power amplifier module 400 can be transmitted to the second sound module 600 through the first switch, thereby driving the second sound module 600 to output sound.

[0069] For example, such as Figure 5 As shown, the first switching transistor and the second switching transistor are the first MOSFET Q1 and the second MOSFET Q2, respectively. When the mobile phone is in earpiece mode, the second sound module 600 does not need to output sound, but the second power amplifier module 400 can still receive ultrasonic signals and form interference signals for feedback to the processing module 100. At this time, the processing module 100 outputs a control signal to the gate of the second MOSFET Q2 to turn on the second MOSFET Q2. After turning on, it pulls the gate of the first MOSFET Q1 low, so that the gate voltage of the first MOSFET Q1 does not meet the conduction condition, and the first MOSFET Q1 turns off, thereby disconnecting the output path between the second power amplifier module 400 and the second sound module 600. In this way, the second power amplifier module 400 can still form interference signals based on ultrasonic signals and transmit them to the processing module 100 through the feedback link, but it will not drive the second sound module 600 to output sound.

[0070] In the above process, the second power amplifier module can participate in the formation and feedback of ultrasonic interference signals when the second sound-generating module is not working, and can also restore normal audio output when the second sound-generating module is working, thus taking into account both interference signal acquisition and acoustic output control.

[0071] Optional, such as Figure 5 As shown, the conduction control subunit includes a power supply terminal PVDD, a first resistor R1, a voltage regulator, a second resistor R2, and a capacitor C1; the second power amplifier module 400 includes a power supply terminal PVDD. The first resistor R1 is connected between the power supply terminal PVDD and the control terminal of the first switching transistor. The voltage regulator is connected to the control terminal of the first switching transistor and is used to limit the voltage at the control terminal of the first switching transistor. The second resistor R2 and capacitor C1 are connected sequentially between the drive output terminal of the second power amplifier module 400 and the control terminal of the first switching transistor, in order to keep the voltage at the control terminal of the first switching transistor higher than the voltage at the drive output terminal of the second power amplifier module 400, so that the first switching transistor is turned on.

[0072] In the embodiments of this application, such as Figure 5 As shown, the first switching transistor is the first MOSFET Q1, the first resistor R1 is used to form a pull-up path with the power supply terminal PVDD, the voltage regulator is the Zener diode DZ1, which is used to limit the conduction voltage to protect the gate of the first MOSFET Q1, the second resistor R2 and the capacitor C1 are connected in sequence between the output terminal of the second power amplifier module 400 and the first MOSFET Q1 to form a bootstrap circuit, which is used to keep the gate voltage of the first MOSFET Q1 higher than the source voltage when the output voltage of the second power amplifier module 400 changes, thereby keeping it on.

[0073] For example, in the speaker working mode of the mobile phone, the output voltage of the second power amplifier module 400 changes with the audio signal. The bootstrap circuit stores the previous voltage through capacitor C1 and, together with the second resistor R2, increases the gate voltage of the first MOSFET Q1, so that the gate voltage of the first MOSFET Q1 is higher than the source voltage, ensuring that it is continuously turned on. After being turned on, the output signal of the second power amplifier module 400 can be transmitted to the speaker to realize the audio output.

[0074] Through the above design, the bootstrap circuit, combined with voltage regulators and pull-up resistors, enables the first switching transistor to remain on when the voltage at the output of the second power amplifier module changes, while protecting the gate from overvoltage. This configuration ensures that the second power amplifier module can drive the acoustic output normally in speaker operating mode.

[0075] like Figure 7 As shown, this application embodiment provides an audio processing method applied to the processing module of the above-mentioned audio control circuit, the method comprising: Step 101: Send an ultrasonic signal to the second power amplifier module via the audio bus so that the second power amplifier module generates an interference signal based on the ultrasonic signal.

[0076] In this embodiment, the ultrasonic signal is a signal whose frequency is outside the normal audible range of the human ear and is used for distance detection or proximity detection. It can be an ultrasonic sweep frequency signal or an ultrasonic pulse signal. The interference signal is a signal formed after the ultrasonic signal is processed by the second power amplification module and is used to characterize the interference components generated by the ultrasonic signal during the driving process. The frequency of the interference signal is usually within the audible range of the human ear.

[0077] For example, taking a mobile phone as an example, after the audio control circuit activates the earpiece mode, the processing module first transmits a 20-24kHz ultrasonic signal to the second power amplifier module through the audio bus. The second power amplifier module generates an interference signal due to the nonlinear response of its internal power amplifier and output link. This interference signal is used to characterize the interference components formed after the ultrasonic signal is driven and processed, providing a basis for the subsequent generation of cancellation signal.

[0078] Step 102: Receive the interference signal transmitted by the second power amplifier module, and generate a cancellation signal based on the interference signal.

[0079] In this embodiment of the application, the cancellation signal is used to cancel the interference components formed after the ultrasonic signal is processed by the first power amplification module when the first power amplification module processes the ultrasonic signal; for example, taking the mobile phone earpiece mode as an example, after the processing module receives the interference signal, it performs phase inversion processing on the interference signal, or performs inversion processing on the sampled values ​​in the interference signal to obtain the cancellation signal.

[0080] Step 103: Mix the cancellation signal, ultrasonic signal and audio signal into a mixed audio signal.

[0081] In this embodiment of the application, the audio signal refers to the service sound signal that needs to be driven by the first power amplification module and output by the acoustic unit. The audio signal can be the downlink voice signal received during the call, or the prompt tone signal generated by the terminal system. In other examples, the audio signal can also be the media playback signal or the voice broadcast signal. The audio signal is usually located in the audible frequency band of the human ear and is used to form sound content that the user can perceive.

[0082] The mixed audio signal can be a digital audio signal formed by superimposing sampling points or a digital audio signal formed by mixing data blocks. The mixed audio signal includes an audio signal for outputting sound, an ultrasonic signal for distance detection, and a cancellation signal for canceling out interference components.

[0083] For example, taking the mobile phone earpiece mode as an example, the processing module mixes the downlink voice signal, ultrasonic signal and cancellation signal to obtain a mixed audio signal, and sends the mixed audio signal to the first power amplification module.

[0084] Step 104: Send the mixed audio signal to the first power amplifier module via the audio bus so that the first power amplifier module can drive the audio based on the mixed audio signal.

[0085] The cancellation signal is used to cancel the interference signal generated after the ultrasonic signal is processed by the first power amplification module.

[0086] In this embodiment of the application, audio driving is the process by which the first power amplifier module receives the mixed audio signal, converts it into a corresponding analog or digital power signal, and then drives the connected acoustic output unit (such as a handset or speaker) to produce sound.

[0087] For example, taking the earpiece mode of a mobile phone, after the first power amplifier module receives the mixed audio signal, the internal drive processing module amplifies and modulates the signal to generate a corresponding differential drive signal. Subsequently, the differential drive signal drives the acoustic output unit, such as the earpiece, to emit sound, which includes the voice content of the business audio signal. At the same time, the interference components generated by the ultrasonic signal are canceled by the cancellation signal in the mixed signal, so as to achieve clean business audio output.

[0088] The above process enables the audio control circuit to effectively suppress ultrasonic signal interference. The processing module sends the ultrasonic signal to the second power amplification module, causing it to generate an interference signal, providing data for subsequent cancellation. The processing module generates a cancellation signal based on this interference signal to correspond to the interference components generated by the ultrasonic signal during the driving process. The processing module mixes the cancellation signal, the ultrasonic signal, and the service audio signal to form a mixed audio signal, thereby performing interference suppression and audio playback in the output link. Through the above processing, audible noise output by the ultrasonic signal in earpiece mode can be effectively reduced, thereby improving call quality.

[0089] For example, taking the earpiece mode of a mobile phone as an example, the processing module sends an ultrasonic signal to the second power amplifier module via the I2S bus. The second power amplifier module generates an interference signal based on the ultrasonic signal and transmits it to the processing module. The transmission of the ultrasonic signal to the second power amplifier module via the I2S bus, and the second power amplifier module's transmission of the interference signal back to the processing module, are mainly completed by the hardware link. This process often takes microseconds. Therefore, the delay introduced by this process is small, and the processing module can quickly obtain the interference signal corresponding to the ultrasonic signal, thereby improving the timeliness of the cancellation signal generation.

[0090] Optionally, step 101 includes sub-steps: Sub-step 1012: Transmit the ultrasonic signal through the transmission signal line, and control the transmission of the ultrasonic signal to the second power amplifier module through the selection signal line; at the same time, enable the second power amplifier module to receive the corresponding ultrasonic signal based on the reading clock provided by the clock signal line.

[0091] For example, taking the audio bus as an I2S bus, the transmission signal line can be the DATA_IN signal line; the selection signal line can be the WS signal line; and the clock signal line can be the SCLK signal line. Within a preset time after the earpiece mode is activated, the processing module transmits the ultrasonic signal through the DATA_IN signal line and controls the second power amplifier module to receive the ultrasonic signal through the corresponding selection state of the WS signal line. The second power amplifier module reads the corresponding ultrasonic signal bit by bit from the DATA_IN signal line based on the read clock provided by the SCLK signal line. Thus, the second power amplifier module can receive the ultrasonic signal at the corresponding channel data position and generate an interference signal based on the ultrasonic signal.

[0092] Step 104 includes sub-step 1041: Sub-step 1041: Transmit the mixed audio signal through the transmission signal line, and control the transmission of the mixed audio signal to the first power amplifier module through the selection signal line; at the same time, enable the first power amplifier module to receive the corresponding mixed audio signal based on the read clock provided by the clock signal line.

[0093] For example, taking the audio bus as an I2S bus, the transmission control logic of the mixed audio signal is the same as that of the ultrasonic signal, which will not be elaborated here.

[0094] By using the transmission signal line, selection signal line, and clock signal line in combination, the ultrasonic signal can be accurately transmitted to the second power amplifier module, and the mixed audio signal can be accurately transmitted to the first power amplifier module. The two power amplifier modules receive signals according to their corresponding reading clocks, thereby reducing signal mistransmission or misreading and ensuring the stability of interference signal generation and mixed audio signal output.

[0095] Optionally, when performing sub-step 1012, the following may also be included: Sub-step 10121: Transmit the reference audio signal through the transmission signal line, and control the transmission of the reference audio signal to the first power amplification module through the selection signal line; the reference audio signal is used to occupy the corresponding channel data position of the first power amplification module when the ultrasonic signal is output.

[0096] In this embodiment, the reference audio signal is audio data used to occupy the corresponding channel data position before the audio signal is officially output. It can be a silence signal or zero-value audio data. This signal itself is not used to form a sound that can be perceived by the user, but is used to keep the channel data position corresponding to the first power amplification module in an effective data transmission state when the ultrasonic signal is output.

[0097] For example, taking the mobile phone earpiece mode as an example, when the processing module transmits an ultrasonic signal to the second power amplifier module through the transmission signal line, the processing module simultaneously transmits a reference audio signal through the transmission signal line, and controls the transmission of the reference audio signal to the first power amplifier module through the selection signal line. At this time, the channel data position corresponding to the first power amplifier module is occupied by the reference audio signal, and the channel data position corresponding to the second power amplifier module receives the ultrasonic signal.

[0098] Optionally, when performing sub-step 1041, the following may also be included: Sub-step 10411: Transmit the reference audio signal through the transmission signal line, and control the transmission of the reference audio signal to the second power amplifier module through the selection signal line; the reference audio signal is used to occupy the corresponding channel data position of the second power amplifier module when the mixed audio signal is output.

[0099] For example, taking the mobile phone earpiece mode as an example, when the processing module transmits the mixed audio signal to the first power amplifier module through the transmission signal line, the processing module simultaneously transmits the reference audio signal through the transmission signal line, and controls the transmission of the reference audio signal to the second power amplifier module through the selection signal line. At this time, the channel data position corresponding to the first power amplifier module receives the mixed audio signal, and the channel data position corresponding to the second power amplifier module is occupied by the reference audio signal. The reference audio signal can be a mute signal or zero-value audio data, which is used to prevent the second power amplifier module from receiving valid service audio data during the mixed audio signal output stage.

[0100] By setting a reference audio signal, the channel data position corresponding to the power amplifier module that has not received a valid output signal can be kept occupied, avoiding channel data being idle or misaligned, thereby ensuring the continuity of transmission of ultrasonic signals and mixed audio signals in the audio bus.

[0101] Optionally, step 101 includes sub-step 1013: Step 1013: Send an ultrasonic signal to the second power amplifier module via the audio bus, so that the second power amplifier module modulates and amplifies the ultrasonic signal to generate a differential drive signal, and performs voltage acquisition on the differential drive signal to obtain voltage feedback information, and generates the interference signal based on the voltage feedback information.

[0102] In this embodiment, the modulation and amplification process is the process by which the second power amplifier module modulates and amplifies the ultrasonic signal after receiving it. The modulation can be pulse width modulation (PWM) modulation or other switching modulation methods suitable for the output stage of an audio power amplifier. The amplification can be power amplification or differential amplification, used to convert the ultrasonic signal into a driving signal that can be output by the output terminal of the second power amplifier module.

[0103] The differential drive signal is a drive signal generated by the second power amplifier module based on the ultrasonic signal and output in a differential form through two output terminals. For example, the differential drive signal can be a differential power signal formed between the positive drive output terminal OUT_P and the negative drive output terminal OUT_N of the power amplifier module, or it can be a differential switching signal formed at the two output terminals after PWM modulation. The differential drive signal is used to characterize the output state of the ultrasonic signal after being driven and processed by the second power amplifier module.

[0104] Voltage acquisition is the process of acquiring the voltage state at the output terminal of the second power amplifier module. For example, voltage acquisition can be achieved through the IV Sense module or through a voltage detection circuit set at the drive output terminal. The object of voltage acquisition can be a single-ended output voltage or a differential output voltage.

[0105] Voltage feedback information is information obtained through voltage acquisition that reflects the voltage state of the differential drive signal. Voltage feedback information can include the voltage amplitude of the differential drive signal, or it can include voltage sampling data formed by the differential drive signal changing over time.

[0106] For example, taking the mobile phone earpiece mode as an example, the processing module sends an ultrasonic signal with a frequency of 22kHz to the second power amplifier module through the audio bus; after receiving the ultrasonic signal, the second power amplifier module modulates and amplifies the ultrasonic signal, and forms a differential drive signal between the drive output terminals OUT_P and OUT_N; for example, at the first sampling time, the voltage of OUT_P is 4V, the voltage of OUT_N is 0V, and the differential voltage between OUT_P and OUT_N is 4V; at the second sampling time, the voltage of OUT_P is 0V, the voltage of OUT_N is 4V, and the differential voltage between OUT_P and OUT_N is -4V.

[0107] The IV Sense module can acquire multiple voltage feedback values ​​according to the audio sampling beat, such as sequentially acquiring voltage feedback values ​​of 4V, 3.6V, 2.8V, 1.5V, 0V, -1.5V, -2.8V, -3.6V, and -4V. Due to the nonlinear response of the second power amplifier module and its output link, the above voltage feedback values ​​may contain interference components formed by the modulation and amplification of the ultrasonic signal. The second power amplifier module generates an interference signal based on the voltage feedback information and feeds the interference signal back to the processing module 100 so that the processing module 100 can subsequently generate a cancellation signal.

[0108] By modulating and amplifying the ultrasonic signal, the second power amplification module can generate a differential drive signal corresponding to the actual drive link. By acquiring the voltage of the differential drive signal and generating voltage feedback information, the output characteristics of the ultrasonic signal after processing by the second power amplification module can be obtained. Furthermore, based on the voltage feedback information, an interference signal is generated, enabling the processing module to obtain interference data corresponding to the current hardware link, providing a basis for the subsequent generation of cancellation signals.

[0109] Optionally, step 102 includes sub-steps 1021-1024: Sub-step 1021: Receive interference signals sequentially according to the order of the data receiving buffer in the circular receiving queue of the processing module; Sub-step 1022: When the current data receiving buffer is full, switch the receiving position to the next data receiving buffer in the circular receiving queue, and process the interference signal in the current data receiving buffer to obtain the corresponding cancellation data. Sub-step 1023: After the interference signal in the current data receiving buffer is processed, the current data receiving buffer is cleared to continue receiving subsequent interference signals until the interference signal transmission is completed. Sub-step 1024: Generate a cancellation signal based on each cancellation data.

[0110] In this embodiment, the data receiving buffer is a data storage area in the processing module used to temporarily store interference signals; the data receiving buffer can be a cache block in memory or a cache segment in the audio data receiving queue.

[0111] The data receiving buffers can be arranged in ascending order of buffer number or in ascending order of buffer address. For example, the processing module can receive interference signals in the order of first data receiving buffer, second data receiving buffer, and third data receiving buffer, and return to the first data receiving buffer after the third data receiving buffer to form a circular receiving queue.

[0112] Cancellation data is the data obtained after processing the interference signal in a data receiving buffer; cancellation data can be the data obtained after phase inversion processing of the interference signal, or the data obtained after inverting the sampled values ​​in the interference signal.

[0113] For example, the processing module sets up three data receiving buffers, denoted as D1, D2, and D3, respectively. Each data receiving buffer is used to buffer 10ms of interference signal data. If the audio sampling rate is 44.1kHz, each data receiving buffer can buffer 441 sampling points. The processing module first writes the interference signal transmitted by the second power amplifier module into D1. When D1 is full, the receiving position is switched to D2 to continue receiving subsequent interference signals. At the same time, the 441 sampling points in D1 are processed to obtain the corresponding cancellation data of D1. Subsequently, when D2 is full, the processing module switches the receiving position to D3 and processes the interference signal in D2. When D3 is full, if the interference signal in D1 has been processed, D1 is cleared so that D1 can continue to receive interference signals. The processing module receives interference signals in the above cyclic manner until the interference signal transmitted by the second power amplifier module is completed, and generates a cancellation signal based on the cancellation data obtained from the corresponding data receiving buffers D1, D2, and D3.

[0114] By cyclically receiving interference signals in multiple data receiving buffers in a specific order, the processing module can process the interference signals in the already full data receiving buffers while receiving subsequent interference signals, thus reducing the waiting time between the receiving and processing processes.

[0115] Optionally, sub-step 1022 includes sub-steps 10221-10223: Sub-step 10221: Divide the interference signals in the current data receiving buffer into multiple processing blocks; Sub-step 10222: Perform phase inversion processing on multiple processing blocks respectively to obtain cancellation blocks corresponding to multiple processing blocks; Sub-step 10223: Combine the offset blocks to obtain offset data.

[0116] In this embodiment, a processing block is a data unit obtained by dividing the interference signal in the current data receiving buffer according to a preset length. The processing block can be a data block divided according to a preset duration or a data block divided according to a preset number of sampling points. For example, a data receiving buffer can correspond to 10ms of interference signal data, and a processing block can correspond to 1ms of interference signal data; or, a data receiving buffer can include 441 sampling points, and a processing block can include 44 sampling points.

[0117] Phase reversal processing is a process that reverses the interference signal in the processing block, so that the processed data has the opposite phase relationship with the original interference signal. Phase reversal processing can be to invert the sampled values ​​in the processing block point by point, or to reverse the waveform corresponding to the processing block relative to zero level. For example, for Pulse Code Modulation (PCM) data, if a sampled value in the processing block is 1000, the corresponding sampled value after phase reversal processing can be -1000; if a sampled value is -800, the corresponding sampled value after phase reversal processing can be 800.

[0118] A cancellation block is a data block obtained by phase inversion of a processing block. A cancellation block can be a data block with the same data length as the processing block, or a data block with the same number of sampling points as the processing block.

[0119] For example, the current data receiving buffer D1 stores 10ms of interference signal data. If the sampling rate is 44.1kHz, then D1 includes 441 sampling points. The processing module can divide the 441 sampling points in D1 into multiple processing blocks, for example, each processing block includes 44 sampling points, corresponding to approximately 1ms of data. Assuming that the sampling values ​​of the sampling points in one of the processing blocks are 1000, 600, -400, and -900 respectively, the processing module performs phase inversion processing on these sampling values ​​to obtain the corresponding cancellation blocks, whose sampling values ​​are -1000, -600, 400, and 900 respectively. The processing module synthesizes the cancellation blocks corresponding to each processing block according to the arrangement order of each processing block in D1 to obtain the cancellation data corresponding to D1.

[0120] By dividing the interference signal in the current data receiving buffer into multiple processing blocks and performing phase reversal processing on each processing block, a large data volume processing process can be split into multiple smaller data volume processing processes, reducing the processing time required for a single algorithm. At the same time, after each processing block is completed, a corresponding cancellation block is obtained, enabling the processing module to receive subsequent interference signals while processing the received interference signals, thereby reducing the impact of the cancellation data generation process on the audio output timing and ensuring that the cancellation data can be used in a timely manner for the generation of subsequent mixed audio signals.

[0121] Optionally, step 103 includes sub-steps 1031-1033: Sub-step 1031: Divide the ultrasonic signal and the audio signal into ultrasonic signal blocks and audio signal blocks that correspond one-to-one with multiple cancellation blocks, respectively; Sub-step 1032: Mix the corresponding cancellation blocks, ultrasonic signal blocks and audio signal blocks respectively to obtain multiple mixed audio blocks; Sub-step 1033: Combine multiple mixed audio blocks to obtain a mixed audio signal.

[0122] In this embodiment of the application, the ultrasonic signal block is a data block obtained by dividing the ultrasonic signal according to a preset data length. It can be a data block divided according to a preset duration or a data block divided according to a preset number of sampling points. For example, the ultrasonic signal block can be ultrasonic data with a length of 1ms or ultrasonic data including 44 sampling points.

[0123] An audio signal block is a data block obtained by dividing an audio signal according to a preset data length. It can be a downlink voice signal block or a reference audio signal block. The downlink voice signal block is used to carry the actual voice data. The reference audio signal block can be a silence data block or a zero-value audio data block, which is used to occupy the corresponding data position before the audio signal is officially output.

[0124] A mixed audio block is a data block obtained by mixing one-to-one corresponding cancellation blocks, ultrasonic signal blocks, and audio signal blocks. It can be a data block obtained by superimposing sampling points or a data block obtained by combining data blocks with the same data length.

[0125] For example, taking a data receiving buffer corresponding to 10ms of data with a sampling rate of 44.1kHz as an example, the data receiving buffer includes 441 sampling points. The processing module can divide the 441 sampling points into multiple processing blocks of about 1ms each. Each processing block includes about 44 sampling points and obtains corresponding cancellation blocks, such as d1`, d2` and d3`.

[0126] When generating the mixed audio signal, the processing module extracts the ultrasound signal and audio signal with the same data length as each cancellation block, and divides the ultrasound signal and audio signal into ultrasound signal blocks and audio signal blocks that correspond one-to-one with multiple cancellation blocks. For example, cancellation block d1' corresponds to ultrasound signal block u1 and audio signal block a1, cancellation block d2' corresponds to ultrasound signal block u2 and audio signal block a2, and cancellation block d3' corresponds to ultrasound signal block u3 and audio signal block a3.

[0127] The processing module mixes the corresponding cancellation blocks, ultrasonic signal blocks, and audio signal blocks to obtain multiple mixed audio blocks. For example, d1', u1, and a1 are mixed to obtain mixed audio block m1, d2', u2, and a2 are mixed to obtain mixed audio block m2, and d3', u3, and a3 are mixed to obtain mixed audio block m3. Subsequently, the processing module 100 synthesizes multiple mixed audio blocks such as m1, m2, and m3 to obtain a mixed audio signal, and sends the mixed audio signal to the first power amplification module.

[0128] As a further example, during the sequential output of multiple mixed audio blocks, the processing module can use Direct Memory Access (DMA) to move the currently output mixed audio block while simultaneously calculating the cancellation blocks corresponding to subsequent mixed audio blocks. For instance, while the DMA is moving the Nth mixed audio block for output by the first power amplifier module 300, the processing module can calculate the cancellation blocks corresponding to the (N+1)th and (N+2)th processing blocks. In this way, the current data output and the generation of subsequent cancellation blocks can be performed in parallel. As long as the calculation time of the cancellation block corresponding to each processing block is less than the output time corresponding to that processing block, the mixed audio signal can be output continuously.

[0129] By dividing the ultrasonic signal, audio signal, and cancellation signal into corresponding data blocks and generating mixed audio blocks by blocks, a large-scale data mixing process can be broken down into multiple smaller-scale processing steps, reducing the time required for a single processing step. Simultaneously, during the output of the current mixed audio block, the processing module can pre-generate the cancellation blocks needed for subsequent mixed audio blocks, allowing cancellation block generation to occur in parallel with the mixed audio block output. This improves the generation speed of the mixed audio signal, reduces output delay caused by waiting for algorithm processing, and ensures that the mixed audio signal can be continuously sent to the first power amplification module.

[0130] Optionally, step 104 includes sub-step 1041: Sub-step 1041: Send the mixed audio signal to the first power amplifier module through the audio bus; so that the first power amplifier module converts the mixed audio signal into a corresponding driving signal, thereby driving the first sound output module to output sound.

[0131] The drive signal is a power signal that the first power amplifier module converts digital or analog audio data into power signals that can drive acoustic output units (such as earpieces or speakers) to produce sound after receiving the mixed audio signal. The drive signal is usually an amplified differential voltage or current signal used to output the information in the mixed audio signal in the form of sound.

[0132] For example, in the earpiece mode of a mobile phone, after the processing module generates a mixed audio signal, it sends the signal to the first power amplifier module via the audio bus. The processing module of the first power amplifier module modulates and amplifies the received mixed audio signal to generate a differential drive signal, which is then emitted through the first acoustic output unit (FAOU), allowing the interference cancellation effect of the service audio signal and the ultrasonic signal to be simultaneously achieved. The formation of the drive signal ensures that the acoustic unit can accurately output the expected audio content, while reducing the audible interference generated by the ultrasonic signal through the drive by the cancellation signal.

[0133] This invention, in its embodiment, sends a mixed audio signal to a first power amplification module to generate a corresponding driving signal, causing the first sound-generating module to output the desired audio. Simultaneously, it compensates for interference components generated by the cancellation signal after the ultrasonic signal has undergone driving processing. This effectively reduces audible interference from the ultrasonic signal to the service audio in earpiece mode, ensuring the clarity and stability of audio playback and improving the user's call quality.

[0134] like Figure 8 The diagram shown is a timing diagram of signal transmission in an audio processing method based on an embodiment of this application. The timing process includes: Step 1. In the initial stage after the earpiece mode is activated, the processing module first enters the preamble stage and sends preamble data through the audio bus within a duration T. The left channel data corresponding to the first power amplifier module is a mute signal, which can be divided into multiple mute data blocks m1, m2, m3…mn. The right channel data corresponding to the second power amplifier module is a mixed ultrasonic signal + mute signal, which can include multiple ultrasonic data blocks s1, s2, s3…sn and their corresponding mute data blocks m1, m2, m3…mn. In other words, within the duration T, the first power amplifier module receives the mute signal, and the second power amplifier module receives the mixed ultrasonic signal + mute signal.

[0135] Step 2. After receiving the ultrasonic signal + mute mixed signal, the second power amplifier module drives the ultrasonic signal. Due to the nonlinear response of the internal power amplifier and output link of the second power amplifier module, the ultrasonic signal is processed by the second power amplifier module to form a demodulated interference signal, which is then transmitted back to the processing module. This process mainly involves hardware link delay, which can be at the microsecond level.

[0136] Step 3. The processing module receives the interference signal returned by the second power amplifier module and writes the interference signal into the data receiving buffer. The data receiving buffer may include D1, D2, D3...Dn; after the current data receiving buffer D1 is full, the processing module switches the receiving position to the next data receiving buffer D2 to continue receiving subsequent interference signals; at the same time, the processing module processes the interference signal in the already full data receiving buffer D1; the interference signal in D1 can be further divided into multiple processing blocks. For example, a 10ms data receiving buffer may include 441 sampling points, and can be logically divided into multiple 1ms processing blocks, each processing block may include approximately 44 sampling points.

[0137] Step 4. The processing module performs phase reversal processing on multiple processing blocks in the data receiving buffer D1 to generate cancellation data D1′ corresponding to D1; the same processing is performed on the interference signals in subsequent data receiving buffers D2, D3...Dn to generate cancellation data D2′, D3′...Dn′ respectively. After processing, the data receiving buffer D1 can be reused as a subsequent data receiving buffer to continue participating in the cyclic reception of interference signals.

[0138] Step 5. After generating the cancellation data, the processing module enters the mixed output stage. The processing module divides the ultrasound signal into multiple ultrasound data blocks s1, s2, s3...sn, the original downlink audio signal into multiple downlink audio data blocks d1, d2, d3...dn, and the cancellation data into corresponding D1′, D2′, D3′...Dn′. In the preamble stage, since the original downlink audio signal has not yet been formally output, the corresponding downlink audio data blocks d1, d2, d3...dn can be mute data blocks; after the audio signal is formally output, the corresponding downlink audio data blocks d1, d2, d3...dn become normal downlink speech data blocks.

[0139] Step 6. The processing module mixes the corresponding data blocks to generate mixed audio blocks. For example, the cancellation data D1′, ultrasound data block s1, and downlink audio data block d1 are mixed to obtain the first mixed audio block; the cancellation data D2′, ultrasound data block s2, and downlink audio data block d2 are mixed to obtain the second mixed audio block; and so on, to obtain multiple mixed audio blocks. Multiple mixed audio blocks are combined to form a mixed audio signal. In the preamble stage, the second power amplification module receives the ultrasound signal + mute mixed signal; after the audio signal is officially output, the first power amplification module receives the ultrasound signal + normal downlink speech mixed signal, and this mixed signal also includes cancellation data used to cancel interference signals.

[0140] Step 7. During the output of the mixed audio signal, the processing module can perform calculations block by block. While the current mixed audio block is being transmitted via the audio bus and driven by the first power amplifier module, the processing module can pre-calculate the cancellation data corresponding to subsequent mixed audio blocks. For example, during the output of the Nth block, the processing module can calculate the cancellation data corresponding to the (N+1)th and (N+2)th blocks. As long as the time required for the processing module to complete the calculation of the cancellation data for a block is less than the playback duration corresponding to that block, continuous output of the mixed audio signal can be guaranteed.

[0141] Step 8. The processing module finally sends the mixed audio signal to the first power amplifier module via the audio bus. The first power amplifier module generates a drive signal based on the mixed audio signal and drives the first sound-generating module to output the sound corresponding to the downlink audio signal.

[0142] Steps 1 and 2 can be defined as a preparatory stage t1, which is used to acquire the interference signal corresponding to the ultrasound signal through the second power amplification module; steps 3 and 4 can be defined as a cancellation generation stage t2, which is used to generate corresponding cancellation data D1′, D2′, D3′…Dn′ based on the interference signals in the data receiving buffers D1, D2, D3…Dn; steps 5 to 8 can be defined as a mixed output stage t3, which is used to mix the cancellation data, ultrasound signal, and downlink audio signal and send them to the first power amplification module. The duration T is greater than or equal to the sum of t1, t2, and t3 to ensure that the acquisition of interference signals, generation of cancellation data, and generation of mixed audio signals are completed before the first power amplification module officially outputs the mixed signal of ultrasound signal + normal downlink audio signal.

[0143] This application also provides a terminal device, including, as in the following embodiments: Figures 4 to 6 The aforementioned audio control circuit.

[0144] Optionally, such as Figure 9 As shown, this application embodiment also provides a terminal device 800, including a processor 801 and a memory 802. The memory 802 stores a program or instructions that can run on the processor 801. When the program or instructions are executed by the processor 801, they implement the various steps of the above-described audio processing method embodiment and can achieve the same technical effect. To avoid repetition, they will not be described again here.

[0145] It should be noted that the terminal devices in this application embodiment include the mobile terminal devices and non-mobile terminal devices described above.

[0146] Figure 10 A schematic diagram of the hardware structure of a terminal device to implement an embodiment of this application.

[0147] The terminal device 1300 includes, but is not limited to, the following components: radio frequency unit 1301, network module 1302, audio output unit 1303, input unit 1304, sensor 1305, display unit 1306, user input unit 1307, interface unit 1308, memory 1309, and processor 1310.

[0148] Those skilled in the art will understand that the terminal device 1300 may also include a power supply (such as a battery) for supplying power to various components. The power supply may be logically connected to the processor 1310 through a power management system, thereby enabling functions such as managing charging, discharging, and power consumption through the power management system. Figure 10The terminal device structure shown in the figure does not constitute a limitation on the terminal device. The terminal device may include more or fewer components than shown, or combine certain components, or have different component arrangements, which will not be elaborated here.

[0149] It should be understood that, in this embodiment of the invention, the input unit 1304 may include a graphics processing unit (GPU) 13041 and a microphone 13042. The GPU 13041 processes image data of still images or videos obtained by an image capture device (such as a camera) in video capture mode or image capture mode. The display unit 1306 may include a display panel 13061, which may be configured in the form of a liquid crystal display, an organic light-emitting diode, or the like. The user input unit 1307 includes a touch panel 13071 and at least one of other input devices 13072. The touch panel 13071 is also called a touch screen. The touch panel 13071 may include a touch detection device and a touch controller. Other input devices 13072 may include, but are not limited to, physical keyboards, function keys (such as volume control buttons, power buttons, etc.), trackballs, mice, and joysticks, which will not be described in detail here.

[0150] The memory 1309 can be used to store software programs and various data. The memory 1309 may primarily include a first storage area for storing programs or instructions and a second storage area for storing data. The first storage area may store the operating system, application programs or instructions required for at least one function (such as sound playback, image playback, etc.). Furthermore, the memory 1309 may include volatile memory or non-volatile memory, or both. The non-volatile memory may be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. Volatile memory can be random access memory (RAM), static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDRSDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link dynamic random access memory (SLDRAM), and direct memory bus RAM (DRRAM). The memory 1309 in this embodiment includes, but is not limited to, these and any other suitable types of memory.

[0151] Processor 1310 may include one or more processing units; optionally, processor 1310 integrates an application processor and a modem processor, wherein the application processor mainly handles operations involving the operating system, user interface, and applications, and the modem processor mainly handles wireless communication signals, such as a baseband processor. It is understood that the aforementioned modem processor may also not be integrated into processor 1310.

[0152] The various embodiments in the specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0153] Although preferred embodiments of the present invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of the present invention.

[0154] The present invention has been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. An audio control circuit, characterized in that, include: Processing module, audio bus, first power amplifier module and second power amplifier module; The output of the processing module is connected to the input of the second power amplifier module via the audio bus. The feedback output of the second power amplifier module is connected to the input of the processing module. The output of the processing module is also connected to the input of the first power amplifier module via the audio bus. The processing module is used to send the ultrasonic signal to the second power amplification module, so that the second power amplification module can generate an interference signal based on the ultrasonic signal and transmit it to the processing module; The processing module is further configured to generate a cancellation signal based on the interference signal, and to mix the cancellation signal, the ultrasonic signal and the audio signal into a mixed audio signal before sending it to the first power amplification module.

2. The audio control circuit according to claim 1, characterized in that, The audio bus includes a select signal line, a transmit signal line, and a clock signal line; The transmission signal line is used to transmit the ultrasonic signal and the mixed audio signal; The selection signal line is used to control the transmission of the ultrasonic signal to the second power amplification module and the transmission of the mixed audio signal to the first power amplification module; The clock signal line is used to provide a read clock, so that the second power amplifier module receives the corresponding ultrasonic signal based on the read clock, and the first power amplifier module receives the corresponding mixed audio signal based on the read clock.

3. The audio control circuit according to claim 1, characterized in that, Both the first power amplification module and the second power amplification module include: a first processing unit and a data acquisition and feedback unit; The input terminal of the first processing unit is connected to the output terminal of the processing module, and is used to receive the ultrasonic signal or the mixed audio signal and generate the corresponding differential drive signal; The input terminal of the acquisition feedback unit is connected to the output terminal of the first processing unit, and the feedback output terminal of the acquisition feedback unit is connected to the input terminal of the processing module. The acquisition feedback unit of the second power amplification module is used to acquire feedback information of the differential drive signal corresponding to the ultrasonic signal, generate the interference signal based on the feedback information, and send it to the processing module.

4. The audio control circuit according to claim 3, characterized in that, The first processing unit includes: a receiving port and a first processing subunit; The input terminal of the first processing subunit is connected to the output terminal of the processing module through the receiving port, and is used to receive the ultrasonic signal or the mixed audio signal through the receiving port; The output of the first processing subunit is connected to the input of the acquisition feedback unit, and is used to modulate and amplify the ultrasonic signal or the mixed audio signal to generate a differential drive signal, which is then sent to the acquisition feedback unit.

5. The audio control circuit according to claim 1, characterized in that, The processing module includes: a storage unit, a transmitter, and a second processing unit; The input terminal of the storage unit is connected to the feedback output terminal of the second power amplifier module, and is used to store the interference signal; The input terminal of the second processing unit is connected to the output terminal of the storage unit, and is used to generate a cancellation signal based on the interference signal, and mix the cancellation signal, the ultrasonic signal and the audio signal into a mixed audio signal; The input terminal of the transmitter is connected to the output terminal of the second processing unit, and the output terminal of the transmitter is connected to the input terminal of the first power amplifier module, for sending the mixed audio signal to the first power amplifier module.

6. The audio control circuit according to claim 1, characterized in that, The audio control circuit further includes: a first sound-generating module, a second sound-generating module, and a path control sub-circuit; The drive output terminal of the first power amplifier module is connected to the first sound module, and is used to drive the first sound module to output the sound corresponding to the mixed audio signal; The drive output terminal of the second power amplifier module is connected to the second sound-generating module through the path control sub-circuit; the path control sub-circuit is used to disconnect the output path between the second power amplifier module and the second sound-generating module when the second power amplifier module generates the interference signal based on the ultrasonic signal, so as to stop driving the second sound-generating module to output sound.

7. The audio control circuit according to claim 6, characterized in that, The path control sub-circuit includes: a first switching transistor, a second switching transistor, and a conduction control sub-unit; the processing module includes a signal output terminal; The first end of the first switching transistor is connected to the drive output terminal of the second power amplifier module, and the second end of the first switching transistor is connected to the second sound-generating module; The first terminal of the second switch is connected to the control terminal of the first switch, and the second terminal of the second switch is grounded. The control terminal of the second switch is connected to the signal output terminal and is used to receive the control signal sent by the processing module. When the second power amplification module generates the interference signal based on the ultrasonic signal, it pulls the control terminal of the first switch low, turns off the first switch, and disconnects the output path. The conduction control subunit is connected to the control terminal of the first switching transistor to control the first switching transistor to conduct when the second power amplifier module drives the second sound output module to output sound, thereby enabling the output path to conduct.

8. The audio control circuit according to claim 7, characterized in that, The conduction control subunit includes a first resistor, a voltage regulator, a second resistor, and a capacitor; the second power amplifier module includes a power supply terminal. The first resistor is connected between the power supply terminal and the control terminal of the first switching transistor, and the voltage regulator is connected to the control terminal of the first switching transistor to limit the voltage at the control terminal of the first switching transistor. The second resistor and the capacitor are connected in sequence between the drive output terminal of the second power amplifier module and the control terminal of the first switch transistor, so as to keep the voltage at the control terminal of the first switch transistor higher than the voltage at the drive output terminal of the second power amplifier module, so as to turn on the first switch transistor.

9. An audio processing method, applied to the processing module of the audio control circuit according to any one of claims 1-8, characterized in that, The method includes: An ultrasonic signal is sent to the second power amplifier module via an audio bus, so that the second power amplifier module generates an interference signal based on the ultrasonic signal. Receive the interference signal transmitted by the second power amplifier module, and generate a cancellation signal based on the interference signal; The cancellation signal, the ultrasonic signal, and the audio signal are mixed into a mixed audio signal; The mixed audio signal is sent to the first power amplifier module via the audio bus, so that the first power amplifier module performs audio driving based on the mixed audio signal; The cancellation signal is used to cancel the interference signal generated after the ultrasonic signal is processed by the first power amplification module.

10. A terminal device, characterized in that, It includes the audio control circuit as described in any one of claims 1-8, and performs the audio processing method as described in claim 9.

Images