Audio power amplifier module, plosive elimination method thereof and audio playing equipment

Abstract

The invention discloses an audio power amplifier module, a plosive elimination method thereof and audio playing equipment, in the audio power amplifier module, a front-end operational amplifier unit comprises at least one operational amplifier which is connected in sequence; the tail end operational amplifier unit comprises a first operational amplifier and a second operational amplifier which are connected in parallel, the non-inverting input ends of the first operational amplifier and the second operational amplifier are respectively connected with one output end of the front end operational amplifier unit, and the inverting input ends of the first operational amplifier and the second operational amplifier are respectively connected with the other output end of the front end operational amplifier unit; the output end of the first operational amplifier is connected with the loudspeaker, and the output end of the second operational amplifier is suspended; the first end of the feedback network is connected with one input end of the front-end operational amplifier unit, and the second end of the feedback network is used for being connected with one output end of the second operational amplifier in the direct-current working point establishing time period and connected with one output end of the first operational amplifier in the power amplification time period. Jumping of electric signals at the two ends of the loudspeaker can be restrained, so that the plosive sound can be reduced, and the plosive sound eliminating effect is improved.

Description

Technical Field

[0001] The present application relates to the field of power amplification technology, and in particular to an audio power amplifier module and a method for eliminating plosive sounds thereof, and an audio playback device. Background Art

[0002] Due to the mismatch of semiconductor process, the operational amplifier has a small non-zero output under 0 input, and this non-zero output can be called offset voltage. Therefore, when the audio amplifier is turned on, even if no data is played, the step signal from 0 to a small non-zero output will cause a momentary "pop" sound at the speaker, which is called a popping sound, such as Figure 1 As shown in Figure 1, this situation seriously affects the user experience. In order to optimize the playback experience, the audio amplifier should eliminate the plosive sound as much as possible.

[0003] Traditional plosive noise elimination technology usually calibrates the operational amplifier so that when the input is 0, the output is as close to 0 as possible, so that the output of the amplifier is as small as possible when it is turned on. However, in actual operation, even if the offset voltage is perfectly eliminated, during the actual startup process of the amplifier, since all nodes of the amplifier need to be established from 0 potential to the DC operating point when it is turned on, although the initial value and final value of the startup process of the voltage at both ends of the speaker are equal (both equal to 0), there are still jumps in the process of each node in the above amplifier being established from 0 potential to the DC operating point, which makes it easy for plosive noises to occur at the speaker end. For example, the startup speeds of the voltages Vop and Von output to the speaker end are inconsistent, such as Figure 2 As shown in FIG. 1 , Vop starts slightly faster than Von, so two jumps will appear at both ends of the speaker, namely Vop-Von. It can be seen that the plosive sound elimination effect of the traditional plosive sound elimination solution is poor. Summary of the invention

[0004] In view of this, the present application provides an audio power amplifier module and a plosive sound elimination method and an audio playback device to solve the problem of poor plosive sound elimination effect of traditional plosive sound elimination solutions.

[0005] The present application provides an audio power amplifier module, comprising a front-end operational amplifier unit, a terminal operational amplifier unit and a feedback network;

[0006] The front-end operational amplifier unit includes at least one operational amplifier connected in sequence;

[0007] The terminal operational amplifier unit comprises a first operational amplifier and a second operational amplifier connected in parallel, wherein the in-phase input terminals of the first operational amplifier and the second operational amplifier are respectively connected to an output terminal of the front-end operational amplifier unit, and the inverting input terminals are respectively connected to another output terminal of the front-end operational amplifier unit, the output terminal of the first operational amplifier is connected to the input terminal of the speaker, and the output terminal of the second operational amplifier is suspended;

[0008] The first end of the feedback network is respectively connected to an input end of the front-end operational amplifier unit, and the second end is used to be respectively connected to an output end of the second operational amplifier during the DC operating point establishment period, and respectively connected to an output end of the first operational amplifier during the power amplification period.

[0009] Optionally, the front-end operational amplifier unit includes a third operational amplifier; the feedback network includes a first resistor and a second resistor; the non-inverting input terminal of the third operational amplifier is connected to the first end of the first resistor, the inverting input terminal is connected to the first end of the second resistor, the non-inverting output terminal serves as an output terminal of the front-end operational amplifier unit, and the inverting output terminal serves as another output terminal of the front-end operational amplifier unit; the second end of the first resistor is used to connect to the inverting output terminal of the first operational amplifier or the inverting output terminal of the second operational amplifier; the second end of the second resistor is used to connect to the non-inverting output terminal of the first operational amplifier or the non-inverting output terminal of the second operational amplifier.

[0010] Optionally, the audio power amplifier module also includes a first switch and a second switch; the first end of the first switch is connected to the second end of the first resistor, and the second end is used to connect to the inverting output end of the first operational amplifier or the inverting output end of the second operational amplifier; the first end of the second switch is connected to the second end of the second resistor, and the second end is used to connect to the non-inverting output end of the first operational amplifier or the non-inverting output end of the second operational amplifier.

[0011] Optionally, the first switch and the second switch respectively include a control end; the audio power amplifier module also includes a control unit; the control unit is respectively connected to the control ends of the first switch and the second switch, and is used to control the second end of the first switch to be connected to the inverting output end of the second operational amplifier during a DC operating point establishment period, and control the second end of the second switch to be connected to the non-inverting output end of the second operational amplifier, and control the second end of the first switch to be connected to the inverting output end of the first operational amplifier during a power amplification period, and control the second end of the second switch to be connected to the non-inverting output end of the first operational amplifier.

[0012] Optionally, the control unit is used to control the second end of the first switch to be connected to the inverting output end of the second operational amplifier, and to control the second end of the second switch to be connected to the non-inverting output end of the second operational amplifier when the audio power amplifier module is connected to an input signal; after a preset time, the second end of the first switch is controlled to be connected to the inverting output end of the first operational amplifier, and the second end of the second switch is controlled to be connected to the non-inverting output end of the first operational amplifier.

[0013] Optionally, the feedback network also includes a third resistor and a fourth resistor; the first end of the third resistor is used to access the first differential input signal, and the second end is connected to the non-inverting input terminal of the third operational amplifier; the first end of the fourth resistor is used to access the second differential input signal, and the second end is connected to the inverting input terminal of the third operational amplifier.

[0014] The present application also provides a method for eliminating the plosive sound of an audio power amplifier module, wherein the method for eliminating the plosive sound of an audio power amplifier module is used to eliminate the plosive sound of any of the above-mentioned audio power amplifier modules, comprising:

[0015] When a power amplifier enable signal is input to the input end of the front-end operational amplifier unit, each second end of the feedback resistor is connected to an output end of the second operational amplifier;

[0016] After a preset time, each second end of the feedback resistor is connected to an output end of the first operational amplifier, and an audio signal is input.

[0017] Optionally, the preset time ranges from 0.5 ms to 10 ms.

[0018] The present application also provides an audio playback device, which includes any of the above-mentioned audio power amplifier modules.

[0019] Optionally, the audio playback device also includes a speaker.

[0020] The above-mentioned audio power amplifier module and its plosive sound elimination method and audio playback device of the present application, during the DC operating point establishment period, the second end of the feedback network is respectively connected to an output end of the second operational amplifier to avoid connecting the speaker to the front-end operational amplifier unit and other operational amplifier units at all levels, which can avoid the generation of plosive sounds in the process of establishing the DC operating point from 0 potential in the operational amplifier units at all levels, so as to achieve the purpose of establishing the DC operating points of as many nodes as possible in each operational amplifier before the operational amplifier units at all levels are connected to the speakers. During the power amplification period, each second end of the feedback network is respectively connected to an output end of the first operational amplifier. At this time, only as few nodes as possible need to establish the DC operating point, so the DC operating point establishment process is simplified to the greatest extent, and the jump of the electrical signals at both ends of the speaker can be suppressed to the greatest extent, thereby minimizing the plosive sound and improving the plosive sound elimination effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0022] Figure 1 This is a schematic diagram of the step signal when the audio amplifier is turned on;

[0023] Figure 2 This is a schematic diagram of the signal jump at the speaker end;

[0024] Figure 3 It is a schematic diagram of the power amplifier structure during the research process;

[0025] Figure 4 It is a structural diagram of an audio power amplifier module according to an embodiment of the present application;

[0026] Figure 5 is a schematic diagram of a front-end operational amplifier unit according to an embodiment of the present application;

[0027] Figure 6 is a structural schematic diagram of an audio power amplifier module according to another embodiment of the present application;

[0028] Figure 7 is a structural schematic diagram of an audio power amplifier module according to another embodiment of the present application;

[0029] Figure 8 is a structural schematic diagram of an audio power amplifier module according to another embodiment of the present application;

[0030] Fig. 9 is a structural schematic diagram of an audio power amplifier module according to another embodiment of the present application;

[0031] Fig.10 is a structural schematic diagram of an audio power amplifier module according to another embodiment of the present application;

[0032] Fig.11 is a schematic diagram of a signal input to a speaker during actual measurement in one embodiment of the present application;

[0033] Fig.12 It is a flowchart of a method for eliminating plosive sound of an audio power amplifier module according to an embodiment of the present application. DETAILED DESCRIPTION

[0034] The technical solutions in the embodiments of the present application are clearly and completely described below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present application. In the absence of conflict, the following embodiments and their technical features can be combined with each other.

[0035] The inventor studied the structure of audio power amplifier and found that in the working process of the power amplifier, a power amplifier structure may include an operational amplifier and four resistors of the feedback network, for example Figure 3The op amp A and R1, R2, R3, R4 are four feedback resistors. Figure 3 Only when the complete connection method shown in the figure is used, the correct DC operating point can be established after power-on and the system can work normally. The op amp is usually composed of multiple stages, and the output of the last stage of the op amp is connected to the speaker. The output waveform of the last stage of the op amp will sound on the speaker. When the audio power amplifier structure is powered on, each stage of the op amp may cause a jump in the output waveform, thereby producing a popping sound at the speaker.

[0036] In view of the above problems, the present application provides an audio power amplifier module according to the first aspect. Figure 4 As shown, the audio power amplifier module includes a front-end operational amplifier unit 110 , a terminal operational amplifier unit 120 and a feedback network 130 .

[0037] The front-end operational amplifier unit 110 includes at least one operational amplifier connected in sequence (or in series) to perform power amplification processing on the input signal in conjunction with an operational amplifier in the terminal operational amplifier unit 120. Figure 5 As shown, the front-end operational amplifier unit 110 includes n operational amplifiers connected in sequence, where n is a positive integer. The non-inverting input terminal (also called the positive input terminal) of the first operational amplifier A31 serves as an input terminal of the front-end operational amplifier unit 110 and is connected to a first terminal of the feedback network 130; the inverting input terminal (also called the negative input terminal) of the first operational amplifier A31 serves as another input terminal of the front-end operational amplifier unit 110 and is connected to another first terminal of the feedback network 130; the inverting output terminal (also called the negative output terminal) of the i-th operational amplifier A3i is connected to the non-inverting input terminal of the i+1-th operational amplifier A3(i+1); the non-inverting output terminal (also called the positive output terminal) of the i-th operational amplifier A3i is connected to the inverting input terminal of the i+1-th operational amplifier A3(i+1); the non-inverting output terminal of the n-th operational amplifier A3n serves as an output terminal of the front-end operational amplifier unit 110, and the inverting output terminal of the n-th operational amplifier A3n serves as another output terminal of the front-end operational amplifier unit 110, 1≤i≤n.

[0038] The terminal operational amplifier unit 120 includes a first operational amplifier A1 and a second operational amplifier A2 connected in parallel; the in-phase input terminals of the first operational amplifier A1 and the second operational amplifier A2 are respectively connected to an output terminal of the front-end operational amplifier unit 110, and the inverting input terminals of the first operational amplifier A1 and the second operational amplifier A2 are respectively connected to another output terminal of the front-end operational amplifier unit 110; the output terminal of the first operational amplifier A1 is connected to the input terminal of the speaker, that is, the in-phase output terminal and the inverting output terminal of the first operational amplifier A1 are respectively connected to an output terminal of the speaker; the output terminal of the second operational amplifier A2 is set to be suspended, such as the in-phase output terminal and the inverting output terminal of the second operational amplifier A2 are respectively set to be suspended.

[0039] The first end of the feedback network 130 is respectively connected to an input end of the front-end operational amplifier unit 110, such as a first end of the feedback network 130 is connected to the non-inverting input end of the first operational amplifier A31, and the other first end is connected to the inverting input end of the first operational amplifier A31; the second end of the feedback network 130 is used to be respectively connected to an output end of the second operational amplifier A2 during the DC operating point establishment period; wherein the DC operating point establishment period refers to a period when an input signal such as an amplifier enable signal is just input to the audio power amplifier module, that is, when an input signal such as an amplifier enable signal is just input to the audio power amplifier module so that the various components of the audio power amplifier module enter the working state, each second end of the feedback network 130 is respectively connected to an output end of the second operational amplifier A2, such as Figure 6 As shown, at this time, the operational amplifier units of each level are not connected to the speaker in the process of establishing from 0 potential to the DC operating point, which can avoid the generation of explosive sound. The second end of the feedback network 130 is also used to connect to an output end of the first operational amplifier A1 during the power amplification period; wherein the power amplification period refers to the period when the audio power amplifier module inputs the audio signal so that the audio power amplifier module performs power amplification processing on the input audio signal and then outputs it to the speaker for playback, that is, when the audio power amplifier module performs power amplification processing on the audio signal, each second end of the feedback network 130 is respectively connected to an output end of the first operational amplifier A1, as shown in FIG. Figure 7 As shown, at this time, the operational amplifier units of each level assist each other in performing power amplification processing on the audio signal, and the audio signal after power amplification processing can be transmitted to the speaker for playback; because the DC operating point of the front-end operational amplifier unit 110 has been established at this stage, only the DC operating point of the first operational amplifier A1 needs to be established, which can minimize the number of electrical signal jumps, thereby reducing the plosive sound as much as possible, that is, minimizing (or minimizing) the plosive sound.

[0040] In the above-mentioned audio power amplifier module, during the DC operating point establishment period, the second end of the feedback network 130 is respectively connected to an output end of the second operational amplifier A2, so as to avoid connecting the speaker to the front-end operational amplifier unit 110 and other operational amplifier units at all levels, thereby avoiding the generation of plosive sounds in the process of establishing the DC operating point from 0 potential in the operational amplifier units at all levels, so as to achieve the purpose of establishing the DC operating points of as many nodes as possible in each operational amplifier before the operational amplifier units at all levels are connected to the speakers. During the power amplification period, each second end of the feedback network 130 is respectively connected to an output end of the first operational amplifier A1. At this time, only as few nodes as possible (such as the nodes corresponding to the first operational amplifier A1) need to establish the DC operating point, so that the DC operating point establishment process is simplified to the greatest extent, and the jump of the electrical signals at both ends of the speaker can be suppressed to the greatest extent, thereby minimizing the plosive sound and improving the effect of eliminating the plosive sound.

[0041] In some embodiments, Figure 8 and Fig. 9 As shown, the front-end operational amplifier unit 110 includes a third operational amplifier A3; the feedback network 120 includes a first resistor R11 and a second resistor R12. The non-inverting input terminal of the third operational amplifier A3 is used as an input terminal of the front-end operational amplifier unit 110, connected to the first end of the first resistor R11 (a first end of the feedback network 130); the inverting input terminal of the third operational amplifier A3 is used as another input terminal of the front-end operational amplifier unit 110, connected to the first end of the second resistor R12 (the other first end of the feedback network 130); the non-inverting output terminal of the third operational amplifier A3 is used as an output terminal of the front-end operational amplifier unit 110, connected to the non-inverting input terminals of the first operational amplifier A1 and the second operational amplifier A2 respectively; the inverting output terminal of the third operational amplifier A3 is used as another output terminal of the front-end operational amplifier unit 110, connected to the inverting input terminals of the first operational amplifier A1 and the second operational amplifier A2 respectively. The second end of the first resistor R11 serves as a second end of the feedback network 130, and is used to connect to the inverting output end of the first operational amplifier A1 or the inverting output end of the second operational amplifier A2; the second end of the second resistor R12 serves as another second end of the feedback network 130, and is used to connect to the non-inverting output end of the first operational amplifier A1 or the non-inverting output end of the second operational amplifier A2.

[0042] Alternatively, if Figure 8 and Fig. 9 As shown, the feedback network 130 further includes a third resistor R13 and a fourth resistor R14. The first end of the third resistor R13 can be used as a third end of the feedback network 130, for receiving the first differential input signal Vip, and the second end of the third resistor R13 is connected to the non-inverting input end of the third operational amplifier A3; the first end of the fourth resistor R14 can be used as another third end of the feedback network 130, for receiving the second differential input signal Vin, and the second end is connected to the inverting input end of the third operational amplifier A3.

[0043] In some embodiments, reference Fig.10As shown, the audio power amplifier module further includes a first switch S1 and a second switch S2. The first end of the first switch S1 is connected to the second end of the first resistor R11, and the second end of the first switch S1 is used to connect the inverting output end of the first operational amplifier A1 or the inverting output end of the second operational amplifier A2. The first end of the second switch S2 is connected to the second end of the second resistor R12, and the second end of the second switch S2 is used to connect the non-inverting output end of the first operational amplifier A1 or the non-inverting output end of the second operational amplifier A2. In this embodiment, the first switch S1 is used to switch between the inverting output end of the first operational amplifier A1 or the inverting output end of the second operational amplifier A2, and the second switch S2 is used to switch between the non-inverting output end of the first operational amplifier A1 or the non-inverting output end of the second operational amplifier A2, so that a relatively simple structure can be used to realize that the feedback network 130 is connected to the second operational amplifier A2 during the DC operating point establishment period, and connected to the first operational amplifier A1 during the power amplification period.

[0044] Specifically, the first switch S1 and the second switch S2 include control terminals (not shown in the figure), respectively; the above-mentioned audio power amplifier module also includes a control unit (not shown in the figure). The control unit is connected to the control terminals of the first switch S1 and the second switch S2, respectively. The control unit is used to control the second terminal of the first switch S1 to connect to the inverting output terminal of the second operational amplifier A2 during the DC operating point establishment period, and control the second terminal of the second switch S2 to connect to the in-phase output terminal of the second operational amplifier A2; the control unit is also used to control the second terminal of the first switch S1 to connect to the inverting output terminal of the first operational amplifier A1 during the power amplification period, and control the second terminal of the second switch S2 to connect to the in-phase output terminal of the first operational amplifier A1, so as to connect the second operational amplifier A2 and the first operational amplifier A1 to the audio power amplifier module in the corresponding period. Optionally, the control unit can be implemented by a chip with low power consumption and stable performance, such as a single-chip microcomputer, to ensure the stability of the switching control process.

[0045] Optionally, the control unit is also used to control the second end of the first switch S1 to be connected to the inverting output end of the second operational amplifier A2, and to control the second end of the second switch S2 to be connected to the non-inverting output end of the second operational amplifier A2 when the audio power amplifier module is connected to an input signal (such as an amplifier enable signal), so that the front-end operational amplifier unit 110 establishes a DC operating point; after a preset time, when the front-end operational amplifier unit 110 completes the establishment of the DC operating point, the second end of the first switch S1 is controlled to be connected to the inverting output end of the first operational amplifier A1, and the second end of the second switch S2 is controlled to be connected to the non-inverting output end of the first operational amplifier A1, so that the first operational amplifier A1 and the front-end operational amplifier unit 110 jointly perform power amplification processing on the input audio signal.

[0046] Optionally, the preset time ranges from 0.5ms to 10ms. For example, the preset time can be 0.5ms, 1ms, 5ms or 10ms, etc., so as to shorten the time as much as possible and improve the startup efficiency of the audio power amplifier module while ensuring that the operational amplifiers of each level in the front-end operational amplifier unit 110 complete the establishment of the DC operating point.

[0047] In the above audio amplifier module, during the DC operating point establishment period, the second end of the feedback network 130 is respectively connected to an output end of the second operational amplifier A2 to avoid connecting the speaker to the front-end operational amplifier unit 110 and other operational amplifier units at all levels, thereby avoiding the generation of plosive sounds in the process of establishing the DC operating point from 0 potential in the operational amplifier units at all levels, so as to achieve the purpose of establishing the DC operating points of as many nodes as possible in each operational amplifier before the operational amplifier units at all levels are connected to the speakers. During the power amplification period, each second end of the feedback network 130 is respectively connected to an output end of the first operational amplifier A1. At this time, only as few nodes as possible need to establish the DC operating point, so the DC operating point establishment process is simplified to the greatest extent, and the jump of the electrical signals at both ends of the speaker can be suppressed to the greatest extent, thereby minimizing the plosive sound and improving the effect of eliminating the plosive sound.

[0048] In addition, the inventors have also conducted actual measurement and analysis on the audio power amplifier modules provided in the above embodiments. The start and stop process of the signal output to the speaker can be referred to in Fig.11 As shown, Fig.11 The signal shown indicates that the jump signal in the signal output to the speaker is reduced to less than 100uV, which effectively reduces the explosive sound, can meet customer needs, and improve the user experience of the corresponding audio playback device.

[0049] A second aspect of the present application provides a method for eliminating the plosive sound of an audio power amplifier module, wherein the method for eliminating the plosive sound of an audio power amplifier module is used to eliminate the plosive sound of the audio power amplifier module described in any of the above embodiments, with reference to Fig.12 As shown, the method for eliminating the plosive sound of the audio power amplifier module includes steps S510 to S520.

[0050] S510, when the power amplifier enable signal is input to the input end of the front-end operational amplifier unit, the second ends of the feedback resistors are respectively connected to an output end of the second operational amplifier, so that when the various components of the audio power amplifier module enter the working state, the feedback network is connected to the second operational amplifier. At this time, the operational amplifier units of each stage are not connected to the speaker in the process of establishing from 0 potential to the DC operating point, which can avoid the generation of explosive sounds.

[0051] S520, after a preset time, each stage of the operational amplifier in the front-end operational amplifier unit completes the establishment of the DC operating point. At this time, each second end of the feedback resistor is connected to an output end of the first operational amplifier, and an audio signal is input. At this time, the operational amplifier units at each stage can assist each other in amplifying the audio signal, and the audio signal after amplification can be transmitted to the speaker for playback; because the DC operating point of the front-end operational amplifier unit has been established at this stage, only the DC operating point of the first operational amplifier needs to be established, which can minimize the number of electrical signal jumps, thereby reducing the plosive sound as much as possible, that is, minimizing the plosive sound.

[0052] Optionally, the preset time ranges from 0.5ms to 10ms. For example, the preset time can be 0.5ms, 1ms, 5ms or 10ms, etc., so as to shorten the time as much as possible and improve the startup efficiency of the audio power amplifier module while ensuring that the operational amplifiers of each level in the front-end operational amplifier unit 110 complete the establishment of the DC operating point.

[0053] The above method for eliminating the plosive sound of the audio power amplifier module is used to eliminate the plosive sound of the audio power amplifier module described in any of the above embodiments, and has all the beneficial effects of the audio power amplifier module described in any of the above embodiments, which will not be repeated here.

[0054] A third aspect of the present application provides an audio playback device, which includes the audio power amplifier module described in any of the above embodiments.

[0055] Specifically, the audio playback device also includes a speaker, which is arranged at the output end of the first operational amplifier, so that when the first operational amplifier is connected to the audio power amplifier module, the operational amplifiers of each level in the front-end operational amplifier unit are combined to perform power amplification processing on the input audio signal, so that the audio signal after power amplification processing is transmitted to the speaker for playback.

[0056] The above-mentioned audio playback device includes the audio power amplifier module described in any of the above-mentioned embodiments, and has all the beneficial effects of the audio power amplifier module described in any of the above-mentioned embodiments, which will not be repeated here.

[0057] Although the present application has been shown and described with respect to one or more implementations, equivalent variations and modifications will occur to those skilled in the art based on reading and understanding of this specification and the accompanying drawings. The present application includes all such modifications and variations and is limited only by the scope of the appended claims. In particular, with respect to the various functions performed by the above-mentioned components, the terms used to describe such components are intended to correspond to any component (unless otherwise indicated) that performs the specified function of the component (e.g., it is functionally equivalent), even if it is not structurally equivalent to the disclosed structure that performs the functions in the exemplary implementation of this specification shown herein.

[0058] That is, the above description is only an embodiment of the present application, and does not limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the specification and drawings of the present application, such as the mutual combination of technical features between the embodiments, or direct or indirect application in other related technical fields, are also included in the patent protection scope of the present application.

[0059] In addition, in the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the drawings, which are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. In addition, for structural elements with the same or similar characteristics, the present application may use the same or different reference numerals for identification. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more features. In the description of the present application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.

[0060] In this application, the word "exemplary" is used to mean "used as an example, illustration or description". Any embodiment described as "exemplary" in this application is not necessarily to be construed as being more preferred or more advantageous than other embodiments. In order to enable any technician in the field to implement and use the present application, the present application provides the above description. In the above description, various details are listed for the purpose of explanation. It should be understood that a person of ordinary skill in the art can recognize that the present application can be implemented without using these specific details. In other embodiments, well-known structures and processes will not be elaborated in detail to avoid unnecessary details that make the description of the present application obscure. Therefore, the present application is not intended to be limited to the embodiments shown, but is consistent with the widest range of principles and features disclosed in the present application.

Claims

1. An audio power amplifier module, characterized in that: The audio power amplifier module includes a front-end operational amplifier unit, a terminal operational amplifier unit and a feedback network; The front-end operational amplifier unit includes at least one operational amplifier connected in sequence; The terminal operational amplifier unit comprises a first operational amplifier and a second operational amplifier connected in parallel, wherein the in-phase input terminals of the first operational amplifier and the second operational amplifier are respectively connected to an output terminal of the front-end operational amplifier unit, and the inverting input terminals are respectively connected to another output terminal of the front-end operational amplifier unit, the output terminal of the first operational amplifier is connected to the input terminal of the speaker, and the output terminal of the second operational amplifier is suspended; The first end of the feedback network is respectively connected to an input end of the front-end operational amplifier unit, and the second end is used to be respectively connected to an output end of the second operational amplifier during the DC operating point establishment period, and respectively connected to an output end of the first operational amplifier during the power amplification period.

2. The audio power amplifier module according to claim 1, characterized in that: The front-end operational amplifier unit includes a third operational amplifier; the feedback network includes a first resistor and a second resistor; The non-inverting input terminal of the third operational amplifier is connected to the first end of the first resistor, the inverting input terminal is connected to the first end of the second resistor, the non-inverting output terminal serves as an output terminal of the front-end operational amplifier unit, and the inverting output terminal serves as another output terminal of the front-end operational amplifier unit; the second end of the first resistor is used to connect to the inverting output terminal of the first operational amplifier or the inverting output terminal of the second operational amplifier; the second end of the second resistor is used to connect to the non-inverting output terminal of the first operational amplifier or the non-inverting output terminal of the second operational amplifier.

3. The audio power amplifier module according to claim 2, characterized in that: The audio power amplifier module also includes a first switch and a second switch; The first end of the first switch is connected to the second end of the first resistor, and the second end is used to connect to the inverting output end of the first operational amplifier or the inverting output end of the second operational amplifier; the first end of the second switch is connected to the second end of the second resistor, and the second end is used to connect to the non-inverting output end of the first operational amplifier or the non-inverting output end of the second operational amplifier.

4. The audio power amplifier module according to claim 3, characterized in that: The first switch and the second switch each include a control terminal; the audio power amplifier module also includes a control unit; The control unit is connected to the control ends of the first switch and the second switch, respectively, and is used to control the second end of the first switch to be connected to the inverting output end of the second operational amplifier during a DC operating point establishment period, and to control the second end of the second switch to be connected to the non-inverting output end of the second operational amplifier, and to control the second end of the first switch to be connected to the inverting output end of the first operational amplifier during a power amplification period, and to control the second end of the second switch to be connected to the non-inverting output end of the first operational amplifier.

5. The audio power amplifier module according to claim 4, characterized in that: The control unit is used to control the second end of the first switch to be connected to the inverting output end of the second operational amplifier when the audio power amplifier module receives an input signal, and to control the second end of the second switch to be connected to the non-inverting output end of the second operational amplifier; after a preset time, the second end of the first switch is controlled to be connected to the inverting output end of the first operational amplifier, and the second end of the second switch is controlled to be connected to the non-inverting output end of the first operational amplifier.

6. The audio power amplifier module according to claim 2, characterized in that: The feedback network also includes a third resistor and a fourth resistor; The first end of the third resistor is used to access the first differential input signal, and the second end is connected to the non-inverting input terminal of the third operational amplifier; the first end of the fourth resistor is used to access the second differential input signal, and the second end is connected to the inverting input terminal of the third operational amplifier.

7. A method for eliminating plosive sound of an audio power amplifier module, characterized in that: Used to eliminate the plosive sound of the audio power amplifier module described in any one of claims 1 to 6; the method comprises: When a power amplifier enable signal is input to the input end of the front-end operational amplifier unit, each second end of the feedback resistor is connected to an output end of the second operational amplifier; After a preset time, each second end of the feedback resistor is connected to an output end of the first operational amplifier, and an audio signal is input.

8. The audio power amplifier module according to claim 7, characterized in that: The preset time has a value range of 0.5 ms to 10 ms.

9. An audio playback device, characterized in that: The audio playback device comprises the audio power amplifier module according to any one of claims 1 to 6.

10. The audio playback device according to claim 9, characterized in that: The audio playback device also includes a speaker.

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