Audio signal processing device and method, audio playing system and chip

Abstract

The invention provides an audio signal processing device and method, an audio playing system and a chip, and relates to the technical field of audio playing. The audio signal processing device comprises an up-sampling module which is used for carrying out up-sampling on a received digital audio signal to be played and sending an obtained first digital audio signal to a first signal output end of the audio signal processing device, and the first signal output end is used for being connected with an input end of a first DAC (Digital-to-Analog Converter) in an audio link of an audio playing system; the selection module is used for selecting a maximum value from the digital audio signal to be played and the first digital audio signal to obtain a second digital audio signal; and the power supply voltage control module is used for performing envelope tracking on the second digital audio signal and sending an obtained third digital audio signal to a second signal output end of the audio signal processing device, which is used for being connected with an input end of a second DAC (Digital-to-Analog Converter) in a power supply link of the audio playing system. According to the scheme, the clipping problem of the audio signal can be solved.

Description

Technical Field

[0001] This application relates to the field of audio playback technology, and in particular to an audio signal processing device and method, an audio playback system and a chip. Background Technology

[0002] With the development of modern technology, audio playback technology is playing an increasingly important role in scenarios such as home theaters, car audio systems, public address systems, wireless audio devices, and multi-device collaboration.

[0003] Figure 1 This diagram illustrates the principle of an audio playback system in the related art. Figure 1 As shown, the digital audio signal to be played is upsampled and then enters the audio link. After being amplified by the power amplifier module in the audio link, the resulting actual audio signal is output to the speaker through the output terminal VOUT of the audio link to drive the speaker to play the digital audio signal. The digital audio signal to be played is also processed by the power supply voltage control module and then enters the power supply link. The power supply link controls the boost module in the power supply link to provide power supply voltage to the power amplifier module in the audio link, that is, to provide power supply voltage to the power amplifier module in the audio link through the power supply terminal PVDD. When the power supply voltage output by the power supply terminal PVDD changes with the envelope of the voltage output by the audio link terminal VOUT, a relatively ideal system efficiency can be achieved.

[0004] However, when the frequency of the digital audio signal to be played is high, for example, when the frequency of the digital audio signal to be played and its corresponding sampling frequency are close to a coherent sampling relationship, the number of sampling points within a signal cycle may be small, potentially losing the peak information of the audio signal. This can cause the power supply voltage control module to fail to detect the signal peak during envelope tracking, resulting in the power supply voltage output by the PVDD terminal of the power supply link being lower than the actual peak value of the audio signal. Meanwhile, because the signal has undergone upsampling on the audio link, the voltage output by the VOUT terminal of the audio link can reconstruct the true peak value of the audio signal. Thus, it is easy for the power supply voltage output by the PVDD terminal to be lower than the voltage output by the VOUT terminal of the audio link, leading to clipping of the signal output by the VOUT terminal of the audio link. Therefore, a solution is needed to address the clipping problem of audio signals in audio playback systems. Summary of the Invention

[0005] This application provides an audio signal processing apparatus and method, an audio playback system and a chip to solve the problem of audio signal clipping in existing audio playback systems.

[0006] In a first aspect, this application provides an audio signal processing device, including an upsampling module, a selection module, and a power supply voltage control module; The upsampling module is used to upsample the received digital audio signal to be played to obtain a first digital audio signal, and send the first digital audio signal to the first signal output terminal of the audio signal processing device; the first signal output terminal is used to connect to the input terminal of the first digital-to-analog converter in the audio link of the audio playback system. The selection module is used to select the maximum value from the digital audio signal to be played and the first digital audio signal to obtain the second digital audio signal; The power supply voltage control module is used to perform envelope tracking on the second digital audio signal to obtain a third digital audio signal, and send the third digital audio signal to the second signal output terminal of the audio signal processing device; the second signal output terminal is used to connect to the input terminal of the second digital-to-analog converter in the power supply link of the audio playback system.

[0007] In one alternative design, the power supply voltage control module includes a detection unit and an envelope tracking unit; The detection unit is used to detect the second digital audio signal to obtain a detected signal. The envelope tracking unit is used to perform envelope tracking on the detector signal to obtain the third digital audio signal, and send the third digital audio signal to the second signal output terminal of the audio signal processing device.

[0008] In an optional design, the audio signal processing device further includes a signal shaping module; The signal shaping module is used to perform noise shaping on the first digital audio signal output by the upsampling module and then send it to the first signal output terminal of the audio signal processing device.

[0009] In one alternative design, the signal shaping module is a Σ-Δ modulator.

[0010] In an alternative design, the audio signal processing device further includes an integrated circuit with a built-in audio bus; The integrated circuit has a built-in audio bus for receiving the externally input digital audio signal to be played, and sending the digital audio signal to be played to the upsampling module and the selection module respectively.

[0011] According to a second aspect, this application provides an audio playback system, including an audio link, a power supply link, and an audio signal processing device as described in any of the first aspects above; the power supply link includes a second digital-to-analog converter and a power supply module; The first signal output terminal of the audio signal processing device is connected to the input terminal of the first digital-to-analog converter in the audio link, the second signal output terminal of the audio signal processing device is connected to the input terminal of the second digital-to-analog converter, and the power supply terminal of the power supply link is connected to the power amplifier power supply terminal of the audio link. The power supply link is used to convert the third digital audio signal output from the second signal output terminal of the audio signal processing device into a second analog signal through the second digital-to-analog converter, and to control the power supply module to provide power supply voltage to the audio link according to the second analog signal; The audio link is used to convert the first digital audio signal output from the first signal output terminal of the audio signal processing device into a first analog signal through the first digital-to-analog converter, and to drive the speaker connected to the power amplifier output terminal of the audio link to play the digital audio signal to be played received by the audio signal processing device according to the first analog signal and the power supply voltage.

[0012] According to a third aspect, this application provides an audio signal processing method, applied to an audio signal processing apparatus as described in any of the first aspects above, or applied to an audio playback system as described in the second aspect above; the audio signal processing method includes: The received digital audio signal to be played is upsampled to obtain a first digital audio signal, and the first digital audio signal is sent to the first signal output terminal of the audio signal processing device so as to play the digital audio signal to be played based on the first digital audio signal through the audio link connected to the first signal output terminal; The second digital audio signal is obtained by selecting the maximum value from the digital audio signal to be played and the first digital audio signal; Envelope tracking is performed on the second digital audio signal to obtain a third digital audio signal, and the third digital audio signal is sent to the second signal output terminal of the audio signal processing device so as to provide a power supply voltage to the audio link based on the third digital audio signal through the power supply link connected to the second signal output terminal.

[0013] In one optional design, upsampling the received digital audio signal to be played to obtain a first digital audio signal, and sending the first digital audio signal to the first signal output terminal of the audio signal processing device, includes: The received digital audio signal to be played is upsampled to obtain the first digital audio signal; The first digital audio signal is noise shaped and then sent to the first signal output terminal of the audio signal processing device.

[0014] According to a fourth aspect, this application provides a chip that includes an audio signal processing apparatus as described in any of the first aspects above, or an audio playback system as described in the second aspect above.

[0015] According to a fifth aspect, this application provides an electronic device including an audio signal processing apparatus as described in any of the first aspects above, or an audio playback system as described in the second aspect above, or a chip as described in the fourth aspect above.

[0016] The audio signal processing apparatus, method, audio playback system, and chip provided in this application upsample the received digital audio signal to be played to obtain an upsampled first digital audio signal. This first digital audio signal is then input to an audio link, enabling the audio link to play the digital audio signal based on the first digital audio signal. Simultaneously, the maximum value is selected from the digital audio signal to be played and the upsampled first digital audio signal to obtain a second digital audio signal. Envelope tracking is then performed on this second digital audio signal, and the envelope-tracked third digital audio signal is input to a power supply link, enabling the power supply link to provide power to the audio link based on the third digital audio signal. Since the upsampled first digital audio signal can restore the true peak value of the audio signal, by using the maximum value of the signal before and after upsampling as the envelope tracking signal, it is ensured that the peak value of the audio signal is detected. When the received digital audio signal to be played loses its peak value due to excessively high signal frequency, the upsampled first digital audio signal can supplement the envelope tracking with the true peak value, ensuring that the signal peak value is detected and tracked, thereby avoiding the clipping problem of the audio signal. Attached Figure Description

[0017] Figure 1 This is a schematic diagram illustrating the principle of an audio playback system in related technologies; Figure 2 This is a schematic diagram showing the curves of the power supply voltage output by the power supply terminal PVDD of the power supply link and the voltage output by the audio link VOUT under ideal conditions in the embodiments of this application. Figure 3 This is a schematic diagram of audio clipping in related technologies; Figure 4 This is one of the structural schematic diagrams of the audio signal processing device provided in the embodiments of this application; Figure 5 This is a second schematic diagram of the structure of the audio signal processing device provided in the embodiments of this application; Figure 6 This is one of the structural schematic diagrams of the audio playback system provided in the embodiments of this application; Figure 7 This is a second schematic diagram of the structure of the audio playback system provided in the embodiments of this application; Figure 8 A flowchart illustrating the audio signal processing method provided in an embodiment of this application; Figure 9 This is a schematic diagram illustrating the effect of the audio signal processing scheme provided in the embodiments of this application. Detailed Implementation

[0018] In this application, "at least one" means one or more, and "more than one" means two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can mean: A alone, A and B simultaneously, or B alone. A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c alone can mean: a alone, b alone, c alone, a combination of a and b, a combination of a and c, a combination of b and c, or a, b, and c. a, b, and c can be single or multiple. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0019] The terms “center,” “longitudinal,” “lateral,” “up,” “down,” “left,” “right,” “front,” and “rear,” etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0020] The terms "connected" and "connected" should be interpreted broadly. For example, in circuit structures, "connected" or "connected" can refer not only to physical connections but also to electrical or signal connections. This could be a direct connection (physical connection) or an indirect connection via at least one intermediate component, as long as the circuit is connected. It could also refer to the internal connection between two components. Similarly, a signal connection can refer to a connection via a circuit or a medium, such as radio waves. Those skilled in the art will understand the specific meaning of these terms in this application based on the specific circumstances.

[0021] according to Figure 1In the audio playback system shown, the boost module in the power supply link acts as the power source, providing power to the power amplifier module's power supply terminal. To prevent clipping at the audio link's output VOUT, the boost module's supply voltage to the power amplifier module's power supply terminal via the power supply terminal PVDD must be greater than the voltage of the signal ultimately output by the audio link's output VOUT. The power supply voltage control module generates a suitable power supply voltage reference signal PVdd_ref based on the digital audio signal to be played, controlling the boost module's operating state to ensure that the supply voltage output by the power supply terminal PVDD is always greater than the voltage of the signal ultimately output by the audio link's output VOUT.

[0022] However, when the supply voltage output by the power supply terminal PVDD is much larger than the voltage of the signal output by the audio link terminal VOUT, it can easily lead to a decrease in the efficiency of the entire audio playback system. Therefore, to ensure the efficiency of the audio playback system, the supply voltage output by the power supply terminal PVDD needs to vary with the envelope of the signal output by the audio link terminal VOUT in order to guarantee good system efficiency.

[0023] Figure 2 This diagram illustrates the curves of the supply voltage PVdd output from the power supply terminal PVDD of the power supply link under ideal conditions and the voltage output from the audio link output terminal VOUT. Figure 1 and Figure 2 As shown, the power supply voltage control module performs envelope tracking on the digital audio signal to be played, generating a suitable power supply voltage reference signal and outputting it to the power supply link. Under the control of the power supply voltage reference signal output by the power supply voltage control module, the power supply link controls the boost module to boost the power supply voltage Vbat, resulting in a power supply voltage PVdd output from the power supply terminal PVDD that is greater than the signal voltage Vout output from the audio link's output terminal VOUT, and it follows the envelope changes of the signal voltage Vout output from the audio link's output terminal VOUT well. It can be understood that in the audio playback system, the power supply link can use the power supply voltage reference signal PVdd_ref output by the power supply voltage control module as a reference, controlling the operating state of the boost module based on the difference between the power supply voltage PVdd and the power supply voltage reference signal PVdd_ref, so that the power supply voltage PVdd output from the power supply terminal PVDD is equal to the power supply voltage reference signal PVdd_ref. Therefore, it is necessary to ensure that the power supply voltage reference signal PVdd_ref output by the power supply voltage control module is greater than the signal voltage Vout output from the audio link's output terminal VOUT.

[0024] according to Figure 1In the audio playback system shown, when the frequency of the digital audio signal to be played and its corresponding sampling frequency (i.e., the signal sampling frequency of the audio playback system) are close or have a coherent sampling relationship (e.g., the system's signal sampling frequency is 48kHz and the frequency of the digital audio signal to be played is 12kHz), there are only 4-5 sampling points in a complete signal cycle. These sampling points are likely to lose the peak information of the audio signal, causing the power supply voltage control module to fail to detect the signal peak, which in turn leads to the power supply voltage PVdd output by the power supply terminal PVDD of the power supply link being less than the signal peak. However, on the corresponding channel of the audio link, after the digital audio signal to be played is upsampled, the true peak value of the audio signal can be restored. Therefore, the signal output by the output terminal VOUT of the audio link has a signal peak value. Thus, when the frequency of the digital audio signal to be played and the sampling frequency corresponding to the digital audio signal to be played (that is, the signal sampling frequency of the audio playback system) are close or have a coherent sampling relationship, the power supply voltage control module may lose the peak value of the signal for a long time. At this time, the power supply voltage reference signal PVdd_ref output by envelope tracking may be less than the voltage of the signal output by the output terminal VOUT. The power supply voltage PVdd output by the power supply terminal PVDD will also be less than the signal voltage Vout output by the output terminal VOUT, thereby generating clipping of the audio signal.

[0025] For example, Figure 3 A schematic diagram of audio clipping in related technologies is shown, where curve ① represents the signal output from the audio link's output terminal VOUT, curve ② represents the digital audio signal to be played, and curve ③ represents the detection result of the power supply voltage control module detecting the digital audio signal to be played. (Refer to...) Figure 3 As shown, when the frequency of the digital audio signal to be played is close to or has a coherent sampling relationship with the sampling frequency corresponding to the digital audio signal to be played, there are only 4 to 5 sampling points in a complete signal cycle, which easily leads to the loss of peak information of the audio signal and the occurrence of clipping phenomenon as shown by the position of the elliptical dashed circle E.

[0026] To address the clipping problem in audio signals caused by lost signal peaks, in one embodiment, a fixed voltage headroom can be superimposed on the supply voltage output from the PVDD power supply terminal, ensuring that the drive voltage input to the speaker at the VOUT output terminal matches the supply voltage. For example, in... Figure 3 In this method, the voltage headroom superimposed on the PVDD output voltage at the power supply end needs to ensure that the superimposed detection result has a peak value greater than the peak value of the audio signal to guarantee that the audio signal is enveloped. This method requires a large voltage headroom, which leads to a decrease in the efficiency of the entire system, and it is difficult to guarantee that the ideal envelope tracking effect can be achieved under different signal frequencies and phase conditions.

[0027] In another embodiment, the detection point of the power supply voltage control module can be placed after upsampling, so that the signal detected by the power supply voltage control module can also have true peak information. However, in this way, the generation time of the power supply voltage reference signal output by the power supply voltage control module is close to the time of the output signal of the audio link's output terminal VOUT, and the power supply voltage PVdd output by the power supply terminal PVDD also requires a certain amount of time from establishment to reaching the required reference value PVdd_ref. This time is usually greater than the loop establishment time of the power amplifier module in the audio link. This will cause the actual output power supply voltage PVdd to be later than the audio signal output by the audio link's output terminal VOUT, which will still cause clipping.

[0028] Based on this, this application provides an audio signal processing scheme that uses the maximum value of the signal before and after upsampling as the input of the power supply voltage control module for envelope tracking. In this way, when the received digital audio signal to be played loses its peak value due to the high signal frequency, the upsampled digital audio signal can transmit the true peak value to the power supply voltage control module for envelope tracking, ensuring that the signal peak value can be detected and tracked, thereby avoiding the clipping problem of the audio signal.

[0029] The following is combined Figures 4-5 The audio signal processing apparatus provided in the embodiments of this application will be described in detail.

[0030] Figure 4 This paper shows one of the structural schematic diagrams of the audio signal processing apparatus provided in an embodiment of this application, with reference to... Figure 4 As shown, the audio signal processing device may include an upsampling module 41, a selection module 42, and a power supply voltage control module 43.

[0031] The upsampling module 41 is used to upsample the received digital audio signal Signal to be played, obtain a first digital audio signal, and send the first digital audio signal to the first signal output terminal S1 of the audio signal processing device. The first signal output terminal S1 is used to connect to the input terminal of the first digital-to-analog converter (DAC) in the audio link of the audio playback system.

[0032] Specifically, assuming the sampling rate of the digital audio signal Signal to be played is fs, and the upsampling factor of the upsampling module 41 is N, then the upsampling module 41 can upsample the digital audio signal Signal to be played to a first digital audio signal with a sampling rate of N*fs. Here, N is an integer greater than 1, such as 64.

[0033] For example, the upsampling module 41 may employ an interpolation filter (INTP).

[0034] The selection module 42 is used to select the maximum value from the digital audio signal Signal to be played and the first digital audio signal to obtain the second digital audio signal, and then input the second digital audio signal to the power supply voltage control module 43.

[0035] Specifically, at each moment, the selection module 42 can compare the digital audio signal Signal to be played with the first digital audio signal, determine the maximum value of the two signal amplitudes at that moment, and obtain the second digital audio signal.

[0036] The power supply voltage control module 43 performs envelope tracking on the second digital audio signal output by the selection module 42 to obtain a third digital audio signal, and sends the third digital audio signal to the second signal output terminal S2 of the audio signal processing device. The second signal output terminal S2 is connected to the input terminal of the second digital-to-analog converter (DAC) in the power supply link of the audio playback system. The third digital audio signal is the required power supply voltage reference signal PVdd_ref, which characterizes the amplitude information of the digital audio signal Signal to be played. The power supply link can use this power supply voltage reference signal PVdd_ref as a reference, and control the operating state of the boost module in the power supply link according to the difference between the power supply voltage PVdd and the power supply voltage reference signal PVdd_ref, so that the output power supply voltage PVdd is equal to the power supply voltage reference signal PVdd_ref.

[0037] Specifically, the power supply voltage control module 43 can track the amplitude of the second digital audio signal according to the envelope tracking algorithm to obtain the third digital audio signal. At this time, since the second digital audio signal is the maximum value of the digital audio signal to be played (Signal) and the upsampled first digital audio signal at each moment, the upsampled first digital audio signal can introduce the peak information of the audio signal into the power supply voltage control module 43. In this way, the power supply voltage control module 43 can track the signal peak when performing envelope tracking, thereby avoiding the clipping problem of the audio signal.

[0038] based on Figure 4 The audio signal processing apparatus corresponding to the embodiment, Figure 5 This is a second schematic diagram of the structure of the audio signal processing device provided in an embodiment of this application, with reference to... Figure 5 As shown, in one embodiment, the audio signal processing device includes an upsampling module 41, a selection module 42, and a power supply voltage control module 43, wherein the power supply voltage control module 43 includes a detection unit 431 and an envelope tracking unit 432.

[0039] The upsampling module 41 can upsample the received digital audio signal Signal to be played and send the obtained first digital audio signal to the first signal output terminal S1 of the audio signal processing device. The first signal output terminal S1 is used to connect to the input terminal of the first DAC in the audio link of the audio playback system.

[0040] The detection unit 431 is used to detect the second digital audio signal output by the selection module 42 to obtain a detected signal; the envelope tracking unit 432 is used to perform envelope tracking on the detected signal output by the detection unit 431 to obtain a third digital audio signal, and sends the third digital audio signal to the second signal output terminal S2 of the audio signal processing device. The second signal output terminal S2 is used to connect to the input terminal of the second DAC in the power supply link of the audio playback system.

[0041] Specifically, the selection module 42 selects the maximum value from the digital audio signal Signal to be played and the first digital audio signal to obtain the second digital audio signal. This second digital audio signal is then input to the detection unit 431, which performs amplitude detection on the second digital audio signal. The resulting detected signal is input to the envelope tracking unit 432, which uses an envelope tracking algorithm to track the detected signal, forming a third digital audio signal that envelops the second digital audio signal. During this process, the upsampled first digital audio signal can introduce peak information of the audio signal into the power supply voltage control module 43. Thus, even when the frequency of the digital audio signal to be played is high—for example, when the frequency of the digital audio signal to be played is close to or has a coherent sampling relationship with its corresponding sampling frequency—and peak information is lost due to fewer sampling points, the detection unit 431 can still detect the peak information. Consequently, when the envelope tracking unit 432 performs envelope tracking, it can also track the peak information of the audio signal, thereby avoiding the clipping problem of the audio signal.

[0042] Reference Figure 5 As shown, in one embodiment, the audio signal processing device may further include an integrated interchip sound (I2S) 51, which is used to receive an externally input digital audio signal Signal to be played and to send the digital audio signal Signal to be played to the upsampling module 41 and the selection module 43 respectively.

[0043] In this way, digital audio signals can be transmitted through the integrated circuit's built-in audio bus 51, avoiding distortion caused by time difference during signal transmission.

[0044] Reference Figure 5 As shown, in one embodiment, the audio signal processing device may further include a signal shaping module 52, which is used to perform noise shaping on the first digital audio signal output by the upsampling module 41 and then send it to the first signal output terminal S1 of the audio signal processing device.

[0045] In this way, by setting a signal shaping module 52 between the upsampling module 41 and the first signal output terminal S1 of the audio signal processing device, the first digital audio signal output by the upsampling module 41 is noise shaped, which can push the quantization noise of the first digital audio signal away from the audio band, thereby improving the signal transmission efficiency and anti-interference ability.

[0046] For example, the signal shaping module 52 can be a Σ-Δ modulator (SDM).

[0047] The audio signal processing apparatus provided in this application embodiment can upsample the received digital audio signal to be played using an upsampling module to obtain an upsampled first digital audio signal. This first digital audio signal is then input to an audio link, enabling the audio link to play the digital audio signal based on the first digital audio signal. Simultaneously, a selection module selects the maximum value from the digital audio signal to be played and the first digital audio signal output by the upsampling module to obtain a second digital audio signal. A power supply voltage control module performs envelope tracking on this second digital audio signal and inputs the envelope-tracked third digital audio signal to the power supply link, enabling the power supply link to provide power to the audio link based on the third digital audio signal. Since the upsampled first digital audio signal can restore the true peak value of the audio signal, by using the maximum value of the signal before and after upsampling as the envelope tracking signal, the peak value of the audio signal can be guaranteed to be detected. When the received digital audio signal to be played loses its peak value due to excessively high signal frequency, the upsampled first digital audio signal can transmit the true peak value to the power supply voltage control module for envelope tracking, thereby avoiding the clipping problem of the audio signal. Moreover, each module in the audio signal processing device can utilize modules from the digital audio power amplifier (PA) system, eliminating the need for additional components and saving costs.

[0048] It is understood that the audio signal processing apparatus provided in the embodiments of this application can be implemented by software, hardware, or a combination of both.

[0049] This application also provides an audio playback system. Figure 6 This paper shows one of the structural schematic diagrams of an audio playback system provided in an embodiment of this application. (Refer to...) Figure 6As shown, the audio playback system may include an audio link 61, a power supply link 62, and an audio signal processing device 63. The audio link 61 may include a first DAC 611 and a power amplifier module 612; the power supply link 62 may include a second DAC 621 and a power supply module 622.

[0050] In this system, the first signal output terminal S1 of the audio signal processing device 63 is connected to the input terminal of the first DAC 611 in the audio link 61, and the second signal output terminal S2 of the audio signal processing device 63 is connected to the input terminal of the second DAC 621. The power supply terminal PVDD of the power supply link 62 is connected to the power amplifier power supply terminal P of the audio link 61, which is also connected to the power amplifier power supply terminal P of the power amplifier module 612 in the audio link 61. The output terminal of the power amplifier module 612 serves as the power amplifier output terminal VOUT of the audio link 61, used for connection to the speaker. The power supply terminal VBAT of the power supply module 622 is used to input the power supply voltage Vbat.

[0051] The audio signal processing device 63 can be any of the audio signal processing devices described in the above embodiments. It can output the first digital audio signal obtained by upsampling the digital audio signal Signal to be played through the first signal output terminal S1, and output the third digital audio signal mentioned above through the second signal output terminal S2.

[0052] The power supply link 62 is used to convert the third digital audio signal output from the second signal output terminal S2 of the audio signal processing device 63 into a second analog signal through the second DAC 621, and control the power supply module 622 to provide power supply voltage to the audio link 61 through the power supply terminal PVDD according to the second analog signal; The audio link 61 is used to convert the first digital audio signal output from the first signal output terminal S1 of the audio signal processing device 63 into a first analog signal through the first DAC 611, and drive the speaker connected to the power amplifier output terminal VOUT of the audio link 61 to play the digital audio signal to be played received by the audio signal processing device 63 according to the first analog signal and the power supply voltage provided by the power supply terminal PVDD of the power supply link 62.

[0053] Specifically, the audio signal processing device 63 can upsample the digital audio signal Signal to be played to obtain a first digital audio signal, which is then input to the first DAC 611 through the first signal output terminal S1. The first DAC 611 converts the first digital audio signal into a first analog signal and inputs it to the power amplifier module 612. Simultaneously, the audio signal processing device 63 can compare the digital audio signal Signal to be played with the first digital audio signal, select the maximum value of the two at each moment to form a second digital audio signal, and then perform detection and envelope tracking on the second digital audio signal to obtain a third digital audio signal. Finally, the third digital audio signal is input to the second DAC 621 through the second signal output terminal S2. The second DAC 621 performs digital-to-analog conversion on the third digital audio signal to obtain a second analog signal, which is then input to the power supply module 622 to control the operating mode of the power supply module 622, enabling the power supply module 622 to provide the power amplifier module 612 with a supply voltage PVdd that is greater than the signal voltage Vout output from the power amplifier output terminal VOUT and varies with the envelope of the signal voltage Vout. The power amplifier module 612 can drive the speaker to play the digital audio signal Signal based on the supply voltage PVdd and the first analog signal output by the first DAC 611.

[0054] For example, the power supply module 622 can compare the power supply voltage PVdd output from the power supply terminal PVDD with the amplitude of the second analog signal output by the second DAC 621. Based on the difference between the power supply voltage PVdd and the amplitude of the second analog signal, the power supply module 622 can adjust the operating mode of the boost circuit in the power supply module 622 in real time, so that the power supply voltage PVdd provided by the power supply module 622 to the power amplifier module 612 is equal to the voltage value of the second analog signal, thereby generating a power supply voltage PVdd that is greater than the signal voltage Vout output by the power amplifier output terminal VOUT and varies with the envelope of the signal voltage Vout.

[0055] based on Figure 6 The audio playback system in the corresponding embodiment uses the audio signal processing device 63 as described above. Figure 5 Taking the audio signal processing device in the corresponding embodiment as an example, Figure 7 This is a second schematic diagram of the structure of the audio playback system provided in an embodiment of this application, with reference to... Figure 7 As shown, the audio playback system includes an audio link 61, a power supply link 62, and an audio signal processing device 63. The audio link 61 may include a first DAC 611 and a power amplifier module 612. The power amplifier module 612 may include a first driver unit 6121 and an output stage power amplifier circuit 6122. The power supply link 62 may include a second DAC 621 and a power supply module 622. The power supply module 622 includes a second driver unit 6221 and a boost circuit 6222.

[0056] The first signal output terminal S1 of the audio signal processing device 63 is connected to the input terminal of the first DAC 611 in the audio link 61, and the second signal output terminal S2 of the audio signal processing device 63 is connected to the input terminal of the second DAC 621. The power supply terminal PVDD of the power supply link 62 is connected to the power amplifier power supply terminal P of the output stage power amplifier circuit 6122 in the audio link 61. The output terminal of the output stage power amplifier circuit 6122 in the power amplifier module 612 serves as the power amplifier output terminal VOUT of the audio link 61, which is used to connect to the speaker M.

[0057] The upsampling module 41 receives the digital audio signal Signal to be played transmitted from the integrated circuit's built-in audio bus 51. After upsampling the Signal, the upsampled first digital audio signal is input to the signal shaping module 52 and the selection module 42. The signal shaping module 52 performs noise shaping on the first digital audio signal output by the upsampling module 41 to push the quantization noise of the first digital audio signal away from the audio band, obtaining a shaped first digital audio signal. Then, the shaped first digital audio signal is input to the first DAC 611 through the first signal output terminal S1. The selection module 42 selects the maximum value from the Signal to be played and the first digital audio signal transmitted from the integrated circuit's built-in audio bus 51 to obtain a second digital audio signal, and then inputs the second digital audio signal to the detection unit 431. The detection unit 431 performs amplitude detection on the second digital audio signal and obtains a detection signal which is input to the envelope tracking unit 432. The envelope tracking unit 432 can use the envelope tracking algorithm to track the detection signal and form a third digital audio signal that can enclose the second digital audio signal. Then, the third digital audio signal is input to the second DAC 621 through the second signal output terminal S2.

[0058] The second DAC 621 performs digital-to-analog conversion on the received third digital audio signal to obtain a second analog signal, which is then input to the second driver unit 6221. The second driver unit 6221 compares the amplitude of the second analog signal with the supply voltage PVdd output from the power supply terminal PVDD, and generates a corresponding control signal based on the comparison result. This control signal is then input to the boost circuit 6222 to control the operating mode of the boost circuit 6222, thereby boosting the power supply voltage Vbat input from the power supply terminal VBAT to a voltage equal to the amplitude of the second analog signal, thus obtaining the supply voltage PVdd. This supply voltage PVdd is then provided to the output stage power amplifier circuit 6122 through the power supply terminal PVDD.

[0059] For example, the boost circuit 6222 can be a BOOST boost circuit, which is a switching DC-DC boost circuit that can include boost mode and shoot-through mode. In boost mode, the connection between the inductor at the input terminal and the power supply terminal PVDD can be controlled by switching the transistor on and off, so that the inductor is in a state of continuous energy storage and release. When the inductor releases energy, the inductor and the power supply together provide energy to the load connected to the power supply terminal PVDD, thereby realizing the boost function. In shoot-through mode, the inductor at the input terminal can be connected to the power supply terminal PVDD by controlling the transistor. At this time, the inductor is in a short-circuit state, and the power supply can directly provide power to the load connected to the power supply terminal PVDD. The second drive unit 6221 can generate a first control signal when it is determined that the power supply voltage PVdd output from the power supply terminal PVDD is less than the amplitude of the second analog signal, and control the boost circuit 6222 to operate in boost mode through the first control signal; when it is determined that the power supply voltage PVdd output from the power supply terminal PVDD is greater than or equal to the amplitude of the second analog signal, it can generate a second control signal, and control the boost circuit 6222 to operate in pass-through mode through the second control signal.

[0060] Specifically, the boost circuit 6222 may include a power supply terminal VBAT, an inductor L, a first switching transistor Q1, a second switching transistor Q2, and an output capacitor Cout. The source of the first switching transistor Q1 and the drain of the second switching transistor Q2 are connected to the first terminal of the inductor L, and the second terminal of the inductor L is connected to the power supply terminal VBAT. The drain of the first switching transistor Q1 is connected to ground GND through the output capacitor Cout, and serves as the power supply terminal PVDD of the power supply link 62, connected to the power amplifier power supply terminal P of the output stage power amplifier circuit 6122 in the audio link 61. The source of the second switching transistor Q2 is connected to ground GND. The output capacitor Cout filters the supply voltage PVdd output from the power supply terminal PVDD.

[0061] When the supply voltage PVdd output from the power supply terminal PVDD is less than the amplitude of the second analog signal, the second drive unit 6221 generates a first control signal. This first control signal controls the first switch Q1 and the second switch Q2 to alternately and complementaryly conduct. That is, the first switch Q1 can alternately turn on and off; when the first switch Q1 is on, the second switch Q2 is off, and when the first switch Q1 is off, the second switch Q2 is on. In this way, the on / off state between the inductor L and the power supply terminal PVDD can be controlled by the first control signal controlling the on / off state of the first switch Q1 and the second switch Q2, keeping the inductor L in a state of continuous energy storage and release, thus achieving the voltage boost function. At this time, the boost circuit 6222 operates in boost mode. When the power supply voltage PVdd output at the power supply terminal PVDD is greater than or equal to the amplitude of the second analog signal, the second drive unit 6221 generates a second control signal, which controls the first switch Q1 to turn on and the second switch Q2 to turn off. At this time, the inductor L is in a short-circuit state, and the voltage at the power supply terminal VBAT is directly connected to the power supply terminal PVDD through the first switch Q1. At this time, the boost circuit 6222 operates in the pass-through mode.

[0062] For example, the first switch Q1 and the second switch Q2 can be an N-type metal-oxide-semiconductor field-effect transistor (MOS transistor) or a P-type MOS transistor.

[0063] The first DAC 611 performs digital-to-analog conversion on the first digital audio signal output from the first signal output terminal S1 to obtain a first analog signal, and then inputs the first analog signal into the first drive unit 6121. The first drive unit 6121 generates a third control signal based on the first analog signal and inputs the third control signal to the output stage power amplifier circuit 6122. The third control signal controls the output stage power amplifier circuit 6122 to drive the speaker M connected to the power amplifier output terminal VOUT, so that the speaker M plays the digital audio signal Signal to be played.

[0064] Specifically, the output stage power amplifier circuit 6122 can be an H-bridge architecture power amplifier circuit, which may include a third switch Q3, a fourth switch Q4, a fifth switch Q5, and a sixth switch Q6. The source of the third switch Q3 and the drain of the fourth switch Q4 are connected. The drain of the third switch Q3 and the drain of the fifth switch Q5 are connected together and then used as the power amplifier power supply terminal P, which is connected to the power supply terminal PVDD of the boost circuit 6222. The source of the fifth switch Q5 and the drain of the sixth switch Q6 are connected. The source of the fourth switch Q4 and the source of the sixth switch Q6 are respectively connected to ground GND. Node A, where the source of the third switch Q3 and the drain of the fourth switch Q4 are connected, and node B, where the source of the fifth switch Q5 and the drain of the sixth switch Q6 are connected, constitute the power amplifier output terminal VOUT of the output stage power amplifier circuit 6122. After the power amplifier output terminal VOUT is connected to the speaker M, the third switch Q3, the speaker M, and the sixth switch Q6 form a connected first half-bridge arm, and the fifth switch Q5, the speaker M, and the fourth switch Q4 form a connected second half-bridge arm. The first drive unit 6121 can use a third control signal to control the gates of the third switch Q3, the fourth switch Q4, the fifth switch Q5, and the sixth switch Q6 to control the conduction or cutoff of the third switch Q3, the fourth switch Q4, the fifth switch Q5, and the sixth switch Q6, thereby controlling the conduction of the first half-bridge arm or the second half-bridge arm to achieve the power amplification function.

[0065] For example, the third switch Q3, the fourth switch Q4, the fifth switch Q5 and the sixth switch Q6 can be N-type MOSFETs or P-type MOSFETs.

[0066] The audio playback system provided in this application embodiment can upsample the received digital audio signal to be played using the audio signal processing device provided in any of the above embodiments to obtain an upsampled first digital audio signal, which is then input to the audio link. Simultaneously, the audio signal processing device selects the maximum value from the digital audio signal to be played and the upsampled first digital audio signal to obtain a second digital audio signal, and performs detection and envelope tracking on the second digital audio signal, inputting the resulting third digital audio signal to the power supply link. The power supply link performs digital-to-analog conversion on the third digital audio signal, and uses the converted second analog signal to control the operating mode of the boost circuit in the power supply link, so that the boost circuit provides a power supply voltage to the output stage power amplifier circuit in the audio link that can envelop the real audio signal. At this time, the audio link can play the digital audio signal to be played based on the first digital audio signal and the power supply voltage provided by the power supply link. On the one hand, since the first digital audio signal after upsampling the digital audio signal to be played can restore the true peak value of the audio signal, by using the maximum value of the signal before and after upsampling as the basis signal for detection and envelope tracking, it can be ensured that the peak value of the true audio signal is detected. When the received digital audio signal to be played loses its peak value due to excessively high signal frequency, the first digital audio signal after upsampling can supplement the envelope tracking with the true peak value, ensuring that the signal peak value can be detected and tracked, thereby avoiding the clipping problem of the audio signal. On the other hand, due to the existence of the upsampling module, the signal finally output by the power amplifier output VOUT of the audio link will be delayed by a certain period of time compared to the I2S output signal. This delay time is at least the group delay time t of the upsampling module (e.g., 200 microseconds). Thus, the power supply voltage control module in the audio signal processing device will detect the increase in signal amplitude at least t (e.g., 200 microseconds) earlier than the audio link, thereby reserving sufficient time for the establishment of the power supply voltage PVdd for the audio link and avoiding the clipping that may occur due to the time required for the audio link to establish the power supply voltage PVdd. Furthermore, each module in the audio signal processing device can utilize modules from existing digital audio power amplifier (PA) systems, without introducing additional components, thus saving system costs.

[0067] This application also provides an audio signal processing method, which can be applied to the audio signal processing device described in any of the above embodiments, or to the audio playback system described in any of the above embodiments.

[0068] Figure 8 A flowchart illustrating the audio signal processing method provided in an embodiment of this application is shown below. Figure 8 As shown, the audio signal processing method may include the following steps 810 to 830.

[0069] Step 810: Upsample the received digital audio signal to be played to obtain a first digital audio signal, and send the first digital audio signal to the first signal output terminal of the audio signal processing device so as to play the digital audio signal to be played based on the first digital audio signal through the audio link connected to the first signal output terminal.

[0070] Specifically, the audio link can control the speaker connected to the audio link to play the digital audio signal based on the first digital audio signal and the power supply voltage provided by the power supply link. At any given moment, the power supply voltage provided by the power supply link is greater than the signal voltage output by the audio link, and changes with the envelope of the signal voltage output by the audio link.

[0071] For example, step 810 upsampling the received digital audio signal to be played to obtain a first digital audio signal and sending the first digital audio signal to the first signal output terminal of the audio signal processing device may include: upsampling the received digital audio signal to be played to obtain a first digital audio signal; and performing noise shaping on the first digital audio signal before sending it to the first signal output terminal of the audio signal processing device.

[0072] For example, a Σ-Δ modulator can be used to perform noise shaping on the first digital audio signal.

[0073] In this way, by performing noise shaping on the upsampled first digital audio signal, the quantization noise of the first digital audio signal can be pushed away from the audio band, thereby improving the signal transmission efficiency and anti-interference capability.

[0074] For example, an interpolation filter (INTP) can be used to upsample the received digital audio signal to be played.

[0075] For example, assuming the sampling rate of the digital audio signal Signal to be played is fs, and the upsampling factor is N, the digital audio signal Signal can be upsampled to a first digital audio signal with a sampling rate of N*fs. Here, N is an integer greater than 1, such as 64. Upsampling can better restore the true waveform of the audio signal.

[0076] Step 820: Select the maximum value from the digital audio signal to be played and the first digital audio signal to obtain the second digital audio signal.

[0077] After upsampling to obtain the first digital audio signal, at each moment, the first digital audio signal and the digital audio signal to be played can be compared to determine the maximum amplitude of the two signals at that moment, forming the second digital audio signal. In this way, if the digital audio signal to be played loses a signal peak, the lost signal peak can be promptly supplemented by the first digital audio signal.

[0078] Step 830: Perform envelope tracking on the second digital audio signal to obtain a third digital audio signal, and send the third digital audio signal to the second signal output terminal of the audio signal processing device so as to provide power supply voltage to the audio link based on the third digital audio signal through the power supply link connected to the second signal output terminal.

[0079] Specifically, after obtaining the second digital audio signal, the amplitude of the second digital audio signal can be detected to obtain the detected signal. Then, the envelope tracking algorithm can be used to track the envelope of the detected signal to obtain the third digital audio signal.

[0080] After receiving the third digital audio signal, the power supply link converts it into a second analog signal. It then compares the output voltage of the power supply link with the amplitude of the second analog signal. Based on the comparison result, it controls the operating mode of the boost circuit in the power supply link, ensuring that the output voltage equals the amplitude of the second analog signal, thus providing the required power supply voltage to the audio link. This power supply voltage is greater than the output voltage of the audio link and varies with the envelope of the audio link's output voltage.

[0081] The audio signal processing method provided in this application can upsample a received digital audio signal to be played to obtain an upsampled first digital audio signal. This first digital audio signal is then input to an audio link, allowing the audio link to play the digital audio signal based on the first digital audio signal. Simultaneously, the maximum value is selected from the digital audio signal to be played and the upsampled first digital audio signal to obtain a second digital audio signal. Envelope tracking is then performed on this second digital audio signal, and the resulting third digital audio signal is input to a power supply link, enabling the power supply link to provide power to the audio link based on the third digital audio signal. Since the upsampled first digital audio signal can restore the true peak value of the audio signal, by using the maximum value of the signal before and after upsampling as the signal for detection and envelope tracking, the peak value of the audio signal can be guaranteed to be detected. When the received digital audio signal to be played loses its peak value due to excessively high frequency, the upsampled first digital audio signal can supplement the envelope tracking with the true peak value, ensuring that the signal peak value is detected and tracked, thereby avoiding the clipping problem of the audio signal. Furthermore, due to the existence of upsampling, the final output signal of the power amplifier VOUT of the audio link will be delayed by a certain period of time compared to the digital audio signal to be played received before signal selection. This delay time is at least the group delay time t of upsampling (e.g., 200 microseconds). In this way, when performing envelope tracking, the increase in signal amplitude will be detected at least 200 microseconds earlier than the audio link by the group delay time t (e.g., 200 microseconds). This provides sufficient time for the audio link to establish the power supply voltage, further avoiding clipping that may occur due to the time required for the audio link to establish the power supply voltage.

[0082] The audio signal processing apparatus, audio playback system, or audio signal processing method based on any of the above embodiments Figure 9 The diagram illustrates the effect of the audio signal processing scheme provided in this embodiment. Curve ④ represents the signal output from the audio link's output terminal VOUT; curve ⑤ represents the digital audio signal to be played; curve ⑥ represents the detection result of the power supply voltage control module detecting the digital audio signal to be played; and curve ⑦ represents the analog signal corresponding to the third digital audio signal output by the power supply voltage control module after envelope tracking of the detection result, which also represents the power supply voltage reference signal PVdd_ref. (Refer to...) Figure 9As shown, according to the audio signal processing scheme provided in the embodiment of this application, the maximum value of the signal before and after upsampling is used as the input of the power supply voltage control module for detection and envelope tracking. The output power supply voltage reference signal PVdd_ref (curve ⑦) is greater than the signal voltage output by the output terminal VOUT. When the frequency of the digital audio signal to be played is high, such as when the frequency of the digital audio signal to be played is close to or has a coherent sampling relationship with the corresponding sampling frequency, the output power supply voltage reference signal PVdd_ref can well envelop the peak value of the signal, thus avoiding the clipping problem.

[0083] This application also provides a chip that may include the audio signal processing device or the audio playback system provided in any of the foregoing embodiments. This chip can achieve the same beneficial effects as the aforementioned audio signal processing device or audio playback system, and will not be elaborated further here.

[0084] This application also provides an electronic device. In one embodiment, the electronic device may include an audio signal processing apparatus as described in any of the above embodiments, or an audio playback system as described in any of the above embodiments, or a chip as described above. This electronic device can achieve the same beneficial effects as the audio signal processing apparatus or audio playback system described above, and will not be elaborated further here.

[0085] In another embodiment, the electronic device provided in this application may include a memory and a processor. The memory stores a computer program that can run on the processor. When the processor executes the program, it implements the steps of the audio signal processing method described in any of the above method embodiments. For example, the audio signal processing method may include: upsampling a received digital audio signal to be played to obtain a first digital audio signal, and sending the first digital audio signal to a first signal output terminal of an audio signal processing device to play the digital audio signal to be played based on the first digital audio signal through an audio link connected to the first signal output terminal; selecting the maximum value from the digital audio signal to be played and the first digital audio signal to obtain a second digital audio signal; performing envelope tracking on the second digital audio signal to obtain a third digital audio signal, and sending the third digital audio signal to a second signal output terminal of the audio signal processing device to provide a power supply voltage to the audio link based on the third digital audio signal through a power supply link connected to the second signal output terminal.

[0086] For example, the electronic devices provided in the embodiments of this application may include at least one of mobile phones, computers, vehicle terminals, tablet computers, wearable devices, smart home devices, augmented reality (AR) devices, and virtual reality (VR) devices, but are not limited thereto.

[0087] Based on the audio signal processing method described in any of the above embodiments, this application also provides a computer-readable storage medium. For example, a non-transitory computer-readable storage medium may be a read-only memory (ROM), a random access memory (RAM), a CD-ROM, magnetic tape, a floppy disk, and an optical data storage device, etc. This storage medium stores computer instructions for executing the audio signal processing method described in any of the above embodiments, which will not be elaborated further here.

[0088] Those skilled in the art will understand that all or part of the steps of the above embodiments can be implemented by hardware, or by a program instructing related hardware to implement them. The program can be stored in a computer-readable storage medium, such as a read-only memory, a disk, or an optical disk.

[0089] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the disclosure herein. This application is intended to cover any variations, uses, or adaptations thereof that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this application are indicated by the claims.

Claims

1. An audio signal processing device, characterized in that, Includes an upsampling module, a selection module, and a power supply voltage control module; The upsampling module is used to upsample the received digital audio signal to be played to obtain a first digital audio signal, and send the first digital audio signal to the first signal output terminal of the audio signal processing device; the first signal output terminal is used to connect to the input terminal of the first digital-to-analog converter in the audio link of the audio playback system. The selection module is used to select the maximum value from the digital audio signal to be played and the first digital audio signal to obtain the second digital audio signal; The power supply voltage control module is used to perform envelope tracking on the second digital audio signal to obtain a third digital audio signal, and send the third digital audio signal to the second signal output terminal of the audio signal processing device; the second signal output terminal is used to connect to the input terminal of the second digital-to-analog converter in the power supply link of the audio playback system.

2. The audio signal processing apparatus according to claim 1, characterized in that, The power supply voltage control module includes a detection unit and an envelope tracking unit; The detection unit is used to detect the second digital audio signal to obtain a detected signal. The envelope tracking unit is used to perform envelope tracking on the detector signal to obtain the third digital audio signal, and send the third digital audio signal to the second signal output terminal of the audio signal processing device.

3. The audio signal processing apparatus according to claim 1, characterized in that, It also includes a signal shaping module; The signal shaping module is used to perform noise shaping on the first digital audio signal output by the upsampling module and then send it to the first signal output terminal of the audio signal processing device.

4. The audio signal processing apparatus according to claim 3, characterized in that, The signal shaping module is a Σ-Δ modulator.

5. The audio signal processing apparatus according to any one of claims 1 to 4, characterized in that, It also includes the integrated audio bus built into the integrated circuit; The integrated circuit has a built-in audio bus for receiving the externally input digital audio signal to be played, and sending the digital audio signal to be played to the upsampling module and the selection module respectively.

6. An audio playback system, characterized in that, It includes an audio link, a power supply link, and an audio signal processing device as described in any one of claims 1 to 5; the power supply link includes a second digital-to-analog converter and a power supply module; The first signal output terminal of the audio signal processing device is connected to the input terminal of the first digital-to-analog converter in the audio link, the second signal output terminal of the audio signal processing device is connected to the input terminal of the second digital-to-analog converter, and the power supply terminal of the power supply link is connected to the power amplifier power supply terminal of the audio link. The power supply link is used to convert the third digital audio signal output from the second signal output terminal of the audio signal processing device into a second analog signal through the second digital-to-analog converter, and to control the power supply module to provide power supply voltage to the audio link according to the second analog signal; The audio link is used to convert the first digital audio signal output from the first signal output terminal of the audio signal processing device into a first analog signal through the first digital-to-analog converter, and to drive the speaker connected to the power amplifier output terminal of the audio link to play the digital audio signal to be played received by the audio signal processing device according to the first analog signal and the power supply voltage.

7. An audio signal processing method, characterized in that, Applied to the audio signal processing apparatus as described in any one of claims 1 to 5, or applied to the audio playback system as described in claim 6; The audio signal processing method includes: The received digital audio signal to be played is upsampled to obtain a first digital audio signal, and the first digital audio signal is sent to the first signal output terminal of the audio signal processing device so as to play the digital audio signal to be played based on the first digital audio signal through the audio link connected to the first signal output terminal; The second digital audio signal is obtained by selecting the maximum value from the digital audio signal to be played and the first digital audio signal; Envelope tracking is performed on the second digital audio signal to obtain a third digital audio signal, and the third digital audio signal is sent to the second signal output terminal of the audio signal processing device so as to provide a power supply voltage to the audio link based on the third digital audio signal through the power supply link connected to the second signal output terminal.

8. The audio signal processing method according to claim 7, characterized in that, The step of upsampling the received digital audio signal to be played to obtain a first digital audio signal, and sending the first digital audio signal to the first signal output terminal of the audio signal processing device, includes: The received digital audio signal to be played is upsampled to obtain the first digital audio signal; The first digital audio signal is noise shaped and then sent to the first signal output terminal of the audio signal processing device.

9. A chip, characterized in that, It includes the audio signal processing apparatus as described in any one of claims 1 to 5, or the audio playback system as described in claim 6.

10. An electronic device, characterized in that, It includes the audio signal processing apparatus as described in any one of claims 1 to 5, or the audio playback system as described in claim 6, or the chip as described in claim 9.

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