CN220401950U - Audio processing circuit and audio playing device - Google Patents

Abstract

The application provides an audio processing circuit and audio playing equipment, wherein the audio processing circuit comprises an audio power amplifier circuit, a power amplifier circuit and a power amplifier circuit, wherein the audio power amplifier circuit is used for receiving an audio signal and amplifying the power of the audio signal; the amplitude detection circuit is an analog circuit and is used for detecting the amplitude of the audio signal; and the power supply circuit is electrically connected with the audio power amplifier circuit and the amplitude detection circuit and is used for receiving the feedback signal from the amplitude detection circuit and adjusting the power supply voltage of the audio power amplifier circuit according to the feedback signal. According to the embodiment of the application, the amplitude detection circuit formed by the analog devices detects the amplitude of the audio signal, the response speed is high, the amplitude of the power supply voltage of the audio power amplifier circuit is adjusted based on the linearity of the amplitude of the audio signal, the efficiency of the audio power amplifier circuit is improved, and the cruising ability of the portable audio playing device is improved.

Description

Audio processing circuit and audio playing device

Technical Field

The present utility model relates to the field of audio devices, and more particularly, to an audio processing circuit and an audio playing device.

Background

The power consumption of the audio power amplifier circuit is one of the main factors affecting the cruising ability of the portable audio playing device. The audio power amplifier circuit is usually powered by a fixed voltage (the voltage required for operating at full power), but in practical use, the audio power amplifier circuit mostly operates in a non-full power state, that is, the fixed voltage is used for power supply, which results in a waste of a part of power consumption.

Disclosure of Invention

The application provides an audio processing circuit and audio playing equipment. Various aspects related to embodiments of the present application are described below.

In a first aspect, an audio processing circuit is provided, comprising: the audio power amplifier circuit is used for receiving an audio signal and amplifying the power of the audio signal; the amplitude detection circuit is an analog circuit and is used for detecting the amplitude of the audio signal to obtain a feedback signal used for representing the amplitude of the audio signal; and the power supply circuit is electrically connected with the audio power amplifier circuit and the amplitude detection circuit and is used for receiving the feedback signal from the amplitude detection circuit and adjusting the power supply voltage of the audio power amplifier circuit according to the feedback signal so that the amplitude of the power supply voltage is matched with the amplitude of the audio signal.

In a second aspect, there is provided an audio playback apparatus comprising: the audio processing circuit of the first aspect; and the loudspeaker is electrically connected with the audio processing circuit and is used for playing the audio signals output by the audio processing circuit.

According to the embodiment of the application, the amplitude detection circuit formed by the analog devices detects the amplitude of the audio signal, the response speed is high, the amplitude of the power supply voltage of the audio power amplifier circuit is adjusted based on the linearity of the amplitude of the audio signal, the efficiency of the audio power amplifier circuit is improved, and the cruising ability of the portable audio playing device is improved.

Drawings

Fig. 1 is a schematic structural diagram of an audio processing circuit according to an embodiment of the present application.

Fig. 2 is a schematic structural diagram of a peak detection circuit according to an embodiment of the present application.

Fig. 3 is a schematic structural diagram of a current source circuit according to an embodiment of the present application.

Fig. 4 is a schematic structural diagram of an amplitude adjusting circuit according to an embodiment of the present application.

Fig. 5 is a schematic structural diagram of an amplitude correction circuit according to an embodiment of the present application.

Fig. 6 is a schematic structural diagram of another audio processing circuit according to an embodiment of the present application.

Fig. 7 is an exemplary diagram of the audio processing circuit of fig. 6.

Fig. 8 is a schematic structural diagram of an audio playing device according to an embodiment of the present application.

Detailed Description

The following description of the technical solutions in the embodiments of the present application will be made clearly and completely with reference to the drawings in the embodiments of the present application, and it is apparent that the described embodiments are only some embodiments of the present application, not all embodiments.

An audio playback device, such as a loudspeaker, converts audio electrical energy into corresponding acoustic energy and radiates it into space, i.e. the audio playback device is a device that converts an audio signal into sound. Power amplification of an audio signal is typically required before the audio playback device converts the audio signal into sound. For example, the loudspeaker may employ an audio power amplifier circuit, such as a power amplifier (which may also be referred to simply as a power amplifier or amplifier), to amplify the power of the audio signal.

In order to meet the use demands of people, portable audio playback devices, such as portable speakers, are increasingly being used. Portable audio playback devices are typically powered by batteries, and thus cruising power is a very important performance indicator of portable audio playback devices. The audio power amplifier circuit for amplifying the power of the audio signal is one of the important factors affecting the cruising ability of the portable audio playing device.

The power consumption of the audio power amplifier circuit can have a certain influence on the cruising ability of the portable audio playing device. Taking the audio power amplifier routing power amplifier group as an example, the power consumption of different kinds of power amplifiers is different. The types of power amplifiers may include, for example, class a power amplifiers, class B power amplifiers, class AB power amplifiers, and class D power amplifiers. Class a power amplifiers can provide excellent sound quality, but consume very much power, severely affecting the cruising ability of the portable audio playback device. The power consumption of the class B power amplifier is greatly reduced compared to the class a power amplifier. However, when the output current of the class B power amplifier crosses zero and the transistor is switched between on and off states, a linear error (crossover distortion) is caused, and thus the sound quality of the class B power amplifier is poor. The class AB power amplifier is a combined circuit of a class A power amplifier and a class B power amplifier, and the tone quality of the class AB power amplifier is superior to that of the class B power amplifier. Although class AB power amplifiers have a power consumption between that of class a and class B power amplifiers, they typically have a power consumption that is closer to that of class B power amplifiers, i.e., they are still larger. Because the class-D power amplifier adopts different topological structures, the power consumption of the class-D power amplifier is smaller than that of any of the class-D power amplifiers. In an ideal case, the efficiency of a class D power amplifier may be 100%; the efficiency can reach about 90% in practical use. That is, the class D power amplifier consumes very little power. The class D power amplifier is widely applied to various audio playing equipment products due to the advantages of high efficiency, high power, low distortion, small volume and the like.

For ease of control, power amplifiers in portable audio playback devices, such as class D power amplifiers, are typically powered with a fixed voltage, and this fixed voltage typically corresponds to the maximum power of the power amplifier. In practical use, however, the power amplifier in the portable audio playback device is mostly operated in a non-full power state, that is, a portion of the power consumption is wasted by using a fixed voltage supply.

Therefore, the related art proposes a method for dynamically adjusting the power supply voltage of the audio power amplifier circuit according to the amplitude of music (i.e., the amplitude of the audio signal), which is beneficial to prolonging the duration of the audio device and prolonging the service life of components in the audio device.

In some embodiments, a control signal associated with the amplitude of the music may be generated based on a controller, such as a single-chip microcomputer, digital signal processor (digital signal processing, DSP), using a software algorithm to perform energy prediction on the audio signal. For example, the control signal may be a pulse width modulated (pulse width modulation, PWM) signal. In addition, the controller may also output the control signal to a feedback terminal of a power supply chip (or referred to as a power supply chip) of the power amplifier through a general-purpose input/output (GPIO) port. Based on this, it is possible to realize that the power supply voltage of the power amplifier varies with the variation of the music amplitude, thereby saving power consumption.

However, the above method has a low voltage adjustment speed, which is liable to cause distortion of the audio signal. To avoid this, the amplitude of the supply voltage of the power amplifier is typically set to a plurality of gear steps, that is, the amplitude of the supply voltage of the power amplifier is not linearly adjusted based on the amplitude of the audio signal. In other words, this operation mode still causes a certain waste of power consumption for the portable audio playing device.

In order to solve the above-mentioned problem, the embodiment of the present application provides an audio processing circuit, which may obtain a feedback signal representing an amplitude of an audio signal through an amplitude detection circuit composed of analog devices, and adjust an amplitude of a supply voltage of an audio power amplifier circuit based on the feedback signal, so that the amplitude of the supply voltage matches with the amplitude of the audio signal. Because the response speed of the analog circuit (or called as a pure hardware circuit) is high, the linear adjustment of the amplitude of the power supply voltage of the audio power amplifier circuit based on the amplitude of the audio signal is facilitated, so that the efficiency of the audio power amplifier circuit is facilitated to be improved, and the cruising ability of the portable audio playing device is further facilitated to be improved.

Fig. 1 is a schematic structural diagram of an audio processing circuit according to an embodiment of the present application. The audio processing circuit 100 may be applied to an audio playback device, such as a portable audio playback device. As an example, the audio processing circuit may be applied to a sound box, and may also be applied to a portable sound box.

Referring to fig. 1, the audio processing circuit 100 may include an audio power amplifier circuit 110, an amplitude detection circuit 120, and a power supply circuit 130.

The audio power amplifier circuit 110 may be configured to receive an audio signal and power amplify the audio signal.

In some embodiments, the audio power amplifier circuit 110 may be a power amplifier circuit, or may be comprised of a power amplifier. For example, the audio power amplifier circuit 110 may be composed of the aforementioned class a power amplifier, class B power amplifier, or class AB power amplifier. Because of the advantages of high efficiency, high power, low distortion, small volume, etc., in order to improve the efficiency of the audio processing circuit 100 and save power consumption, the audio power amplifier circuit 110 may be composed of a class D power amplifier, or, in other words, the audio power amplifier circuit 110 is a class D power amplifier circuit.

In some embodiments, the audio processing circuit 100 may also include an amplitude detection circuit 120. Wherein the amplitude detection circuit 120 may be configured to detect the amplitude of the audio signal, resulting in a feedback signal that is used to characterize the amplitude of the audio signal. For example, the amplitude detection circuit 120 may detect the amplitude of the audio signal and then generate a feedback signal characterizing the amplitude of the audio signal based on the detected amplitude of the audio signal.

The audio signal mentioned herein may be an audio signal received by the above-mentioned audio power amplifier circuit 110. As an implementation, an input of the amplitude detection circuit 120 may be connected to the audio signal in parallel with an input of the audio power amplifier circuit 110.

In some embodiments, the amplitude detection circuit 120 may be an analog circuit, or a pure hardware circuit. The analog circuit may be a circuit directly or indirectly composed of analog devices such as resistors, capacitors, triodes, metal-oxide-semiconductor field-effect transistor (MOSFET, which may be simply referred to as MOS transistor), and the like. In this way, the amplitude detection circuit 120 can achieve a faster response speed.

The power supply circuit 130 may be electrically connected to the audio power amplifier circuit and the amplitude detection circuit. The supply circuit 130 may be configured to provide a supply voltage to the audio power amplifier circuit 110. In some embodiments, the supply circuit may adjust the supply voltage of the audio power amplifier circuit according to the feedback signal received from the amplitude detection circuit 120 such that the amplitude of the supply voltage matches the amplitude of the audio signal. That is, when the feedback signal changes, the power supply circuit 130 may adjust the power supply voltage of the audio power amplifier circuit so that the amplitude of the power supply voltage of the audio power amplifier circuit matches the amplitude of the audio signal.

The amplitude of the supply voltage is matched with the amplitude of the audio signal, which may mean that the amplitude of the supply voltage meets the amplitude requirement of the audio signal, for example, the amplitude of the supply voltage is exactly equal to the requirement of the audio signal amplitude on the supply voltage, or is slightly greater than the requirement of the audio signal amplitude on the supply voltage. Therefore, the power consumption can be reduced as much as possible on the basis of meeting the processing requirements of the audio signals.

In the embodiment of the application, the feedback signal representing the amplitude of the audio signal can be obtained through the amplitude detection circuit of the pure hardware, and the amplitude of the power supply voltage of the audio power amplifier circuit is dynamically adjusted based on the feedback signal, so that the linear adjustment of the amplitude of the power supply voltage of the audio power amplifier circuit based on the amplitude of the audio signal is facilitated, the efficiency of the audio power amplifier circuit is improved, and the cruising ability of the portable audio playing equipment is improved.

Based on the characteristics of the audio signal, a feedback signal characterizing the amplitude of the audio signal may be derived from the peak value of the amplitude of the audio signal. In some embodiments, the amplitude detection circuit 120 may include a peak detection circuit that may be used to detect peaks in the amplitude of the audio signal.

Fig. 2 is a schematic structural diagram of a peak detection circuit according to an embodiment of the present application. The peak detection circuit 200 may include a first op-amp 210, a first diode 220, a first resistor 230, and a first capacitor 240. The first operational amplifier may be referred to as PA1, the first diode may be referred to as D1, the first resistor may be referred to as R1, and the first capacitor may be referred to as C1. Similar descriptions can be used for the analog devices mentioned hereinafter, such as the X-th resistor has the same meaning as RX.

Referring to fig. 2, an anode of the first diode 220 may be connected to an output terminal of the first operational amplifier 210, a cathode of the first diode 220 may be connected to an inverting input terminal of the first operational amplifier 210, and one terminal of the first resistor 230. The other end of the first resistor 230 is connected to one end of the first capacitor 240, and the other end of the first capacitor 240 is grounded. The first resistor 230 and the first capacitor 240 form a filter.

The non-inverting input of the first op-amp 210 is an input of the peak detection circuit, that is, the non-inverting input of the first op-amp 210 may be connected to an audio signal. The output of the peak detection circuit is the end of the first capacitor 240 connected to the first resistor 230.

In some embodiments, the peak detection circuit may further include a ninth resistor 250, and the ninth resistor 250 may be connected in parallel across the first capacitor 240.

The peak detection circuit may decimate and smoothly connect peaks of the audio signal. The power supply voltage of the audio power amplifier circuit is controlled based on the peak value of the amplitude of the audio signal, and the method is simple to realize and high in stability.

The feedback signal may be a voltage feedback signal or a current feedback signal. For example, the amplitude detection circuit 120 may also include a current source circuit that may be used to generate a current feedback signal. As an example, the current source circuit may be connected to the peak detection circuit for generating a current signal according to a detection result of the peak detection circuit and transmitting the current signal as a feedback signal to the power supply circuit.

Fig. 3 is a schematic structural diagram of a current source circuit according to an embodiment of the present application. The current source circuit 300 may include a second operational amplifier 310, a MOS transistor 320, a second resistor 330, a third resistor 340, and a fourth resistor 350. In some embodiments, MOS transistor 320 is an N-channel MOS transistor.

Referring to fig. 3, an output terminal of the second operational amplifier 310 is connected to one end of the second resistor 330, and the other end of the second resistor 330 is connected to the gate of the MOS transistor 320. The source of the MOS transistor 320 is connected to one end of the third resistor 340 and the inverting input end of the second operational amplifier 320, and the other end of the third resistor 340 is grounded. The source of the MOS transistor 320 is connected to one end of the fourth resistor 350.

The input end of the current source circuit is the non-inverting input end of the second operational amplifier 310, and the output end of the current source circuit is the other end of the fourth resistor 350, that is, the other end of the fourth resistor 350 outputs a current feedback signal.

The ratio of the input voltage of the current source circuit to the third resistor 340 is the source current of the MOS transistor, that is, the current value (may be denoted as Id) on the drain-source of the MOS transistor. The current source current can thus convert the input voltage into a corresponding current feedback signal.

Generally, the power supply circuit 130 performs negative feedback voltage or current regulation to achieve stability of the output voltage. In some embodiments, the feedback signal generated by the current source circuit may be superimposed on the feedback signal of the power supply circuit itself, so that the amplitude of the power supply voltage and the audio signal linearly change on the basis of ensuring that the voltage provided by the power supply circuit 130 is stable, thereby contributing to improving efficiency.

In general, the power supply circuit 130 may include a feedback terminal. But the input voltage and/or current requirements at the feedback terminals may be different for different power supply circuits. For example, the power supply circuit may be implemented using a power supply chip, such as a boost power supply chip. For power chips of different manufacturers or different packages, the input voltage and/or current of the feedback end of the power chip needs to meet a certain range. Therefore, in order to meet the requirement of the feedback terminal of the power supply circuit 130, the amplitude detection circuit 120 may further include an amplitude adjustment circuit for adjusting the amplitude of the audio signal so that the feedback signal obtained based on the audio signal meets the requirement of the feedback terminal of the power supply circuit 130.

Meanwhile, in order to ensure that the audio signal is not distorted, the amplitude of the audio signal may be scaled. That is, the amplitude adjustment circuit may be a proportional adjustment circuit, i.e., the ratio of the input voltage amplitude and the output voltage amplitude of the amplitude adjustment circuit is a fixed ratio.

In some embodiments, the amplitude adjustment circuit may be electrically connected to the peak detection circuit for receiving an input voltage of the audio signal and for scaling a voltage amplitude of the input voltage of the audio signal. That is, the input of the amplitude adjustment circuit is the voltage of the audio signal, the output is the audio signal after the scaling, and the output of the amplitude adjustment circuit is the input of the peak detection circuit.

Since the voltage amplitude of the audio signal is usually smaller, an amplitude adjusting circuit with larger input impedance can be used to adjust the voltage amplitude of the audio signal, so as to avoid adverse effect of the circuit on the audio signal. In some embodiments, the amplitude adjustment circuit may be a proportional circuit consisting of an op-amp.

Fig. 4 is a schematic structural diagram of an amplitude adjusting circuit according to an embodiment of the present application. The amplitude adjustment circuit 400 may include a third operational amplifier 410, a fifth resistor 420, a sixth resistor 430, and a second diode 440.

Referring to fig. 4, the inverting input terminal of the third operational amplifier 410 is connected to one terminal of the fifth resistor 420 and one terminal of the sixth resistor 430, and the other terminal of the fifth resistor 420 is grounded. An anode of the second diode 440 is connected to an output terminal of the third op amp 410, and a cathode of the second diode 440 is connected to the other end of the sixth resistor 430.

In some embodiments, the cathode of the second diode 440 may be further connected to one end of the tenth resistor 450, and the other end of the tenth resistor 450 is grounded. In other embodiments, the non-inverting input of the third op-amp 410 may also be coupled to the second capacitor 460.

The input of the amplitude adjustment circuit may be the non-inverting input of the third op-amp 410, that is, the non-inverting input of the third op-amp 410 may be connected to the audio signal. The output of the amplitude adjustment circuit may be the cathode of the second diode 440.

If the fifth resistor is denoted as R5, the sixth resistor is denoted as R6, the input voltage of the amplitude adjustment circuit is denoted as Vin, and the output voltage is denoted as Vout, the relationship between the input voltage and the output voltage of the amplitude adjustment circuit is: vout= (1+r6/R5) Vin. Therefore, the amplitude ratio of the output voltage to the input voltage of the amplitude adjusting circuit can be adjusted through the resistance value setting of R5 and R6.

The peak detection circuit typically introduces some amplitude distortion and thus the amplitude detection circuit may also include an amplitude correction circuit.

In some embodiments, an input of the amplitude correction circuit may be electrically connected to the peak detection circuit and an output of the amplitude correction circuit may be electrically connected to the current source circuit. For example, an input of the amplitude correction circuit may be electrically connected to an output of the peak detection circuit, and an output of the amplitude correction circuit may be electrically connected to an input of the current source circuit.

The amplitude correction circuit may be configured to correct a voltage amplitude of the output voltage of the peak detection circuit to compensate for amplitude distortion caused by the peak detection circuit.

Fig. 5 is a schematic structural diagram of an amplitude correction circuit according to an embodiment of the present application. The amplitude correction circuit 500 may include a fourth operational amplifier 510, a seventh resistor 520, and an eighth resistor 530.

Referring to fig. 5, the inverting input terminal of the fourth operational amplifier 510 is connected to one terminal of the seventh resistor 520 and one terminal of the eighth resistor 530, the other terminal of the seventh resistor 520 is grounded, and the other terminal of the eighth resistor 530 is connected to the output terminal of the fourth operational amplifier 520.

In some embodiments, the amplitude correction circuit further includes an eleventh resistor 540, one end of which is connected to the non-inverting input terminal of the fourth operational amplifier 510, and the other end of which is grounded.

The input end of the amplitude correction circuit is the non-inverting input end of the fourth operational amplifier 510, and the output end is the output end of the fourth operational amplifier 510. Similar to the principle of the amplitude adjustment circuit, the relation between the input voltage and the output voltage of the amplitude correction circuit can be adjusted by adjusting the resistances of the seventh resistor 520 and the eighth resistor 530. In practical use, the resistance values of the seventh resistor 520 and the eighth resistor 530 may be determined according to the amplitude distortion condition of the peak detection circuit.

The audio processing circuit provided by the embodiment of the application can help to improve the efficiency of the audio power amplification circuit under the condition that the power amplification output audio signal is not distorted, so that the portable audio playing device with a battery can realize the user experience of long endurance.

The following describes an audio processing circuit provided in the embodiment of the present application, taking a power supply circuit as a boost module as an example.

Fig. 6 is a schematic structural diagram of another audio processing circuit according to an embodiment of the present application. The audio processing circuit 600 may include an audio power amplifier circuit 610, an amplitude detection circuit 620, and a power supply circuit 630.

Referring to fig. 6, the audio power amplifier circuit 610 may be the aforementioned audio power amplifier circuit 110, where the input of the audio power amplifier circuit 610 is an audio signal, and the output is an amplified audio signal (not shown in the figure). The audio power amplifier circuit 610 further includes a power supply terminal for receiving a power supply voltage thereof.

The amplitude detection circuit 620 may include an amplitude adjustment circuit 621, a peak detection circuit 622, an amplitude correction circuit 623, and a current source circuit 624. The input of the amplitude detection circuit 620 (i.e., the input of the amplitude adjustment circuit 621) is an audio signal, and the output of the amplitude detection circuit 620 (i.e., the output of the current source circuit) is a feedback signal representing the amplitude of the audio signal. Wherein the output terminal of the amplitude adjustment circuit 621 is connected to the input terminal of the peak detection circuit 622, the output terminal of the peak detection circuit 622 is connected to the input terminal of the amplitude correction circuit 623, and the output terminal of the amplitude correction circuit 623 is connected to the input terminal of the current source circuit 624.

The power supply circuit 630 may be a boost power chip, an input terminal of the power supply circuit may be connected to the battery 640, and an output terminal of the power supply circuit may be connected to a power supply terminal of the audio power amplifier circuit 610. While the feedback terminal of the power supply circuit 630 is connected to the output voltage and the output terminal of the amplitude detection circuit 620.

According to the method and the device, the linear amplitude of the original audio signal is estimated, the feedback signal is generated and output to the feedback end pin of the boost power supply chip, and therefore the output voltage amplitude of the boost power supply chip is controlled to linearly match the power supply voltage amplitude just enough for the audio power amplifier circuit. The method can help to improve the efficiency of the audio power amplifier circuit under the condition that the audio signal output by the audio power amplifier circuit is not distorted.

Fig. 7 is an exemplary diagram of the audio processing circuit of fig. 6. The audio processing circuit 700 may include an audio power amplifier circuit 710, an amplitude detection circuit 720, and a power supply circuit 730. The amplitude detection circuit 720 may include the amplitude adjustment circuit 400, the peak detection circuit 200, the amplitude correction circuit 500, and the current source circuit 300 described above.

According to the requirement of the feedback end of the boost power supply chip or the size relation between the audio signals with different voltage amplitudes and the feedback end, the proportional relation between the input voltage and the output voltage of the amplitude adjusting circuit can be determined. The resistance value of the resistor in the amplitude adjustment circuit 400 can be determined based on the proportional relationship.

The peak detection circuit can extract the peak value of the audio signal and carry out smooth connection through the filter to obtain the peak detection result of the audio signal.

Based on the degree of distortion of the peak detection result of the peak detection circuit, the proportional relationship between the input voltage and the output voltage of the amplitude correction circuit 500 can be determined. The resistance value of the resistor in the amplitude correction circuit 500 can be determined based on the proportional relationship.

The current source circuit can convert the amplitude of the audio signal into a current feedback signal and output the signal to the feedback end of the boost power supply chip.

The feedback terminal of the boost power supply chip is usually connected to the feedback signal of the output voltage, and a manner of determining the output voltage of the boost power supply chip based on the feedback signal of the output voltage and the current feedback signal provided by the current source circuit will be described below.

In some embodiments, the voltage output Vo of the power supply circuit 730 may be connected to the power supply terminal of the audio power amplifier circuit and one terminal of the twelfth resistor. The other end of the twelfth resistor may be connected to the feedback terminal FB of the power supply circuit 730, one end of the thirteenth resistor, and the output terminal of the current source circuit, respectively. The other end of the thirteenth resistor is grounded.

The relationship between the feedback signal provided by the current source circuit and the output voltage of the power supply circuit 730 can be calculated based on kirchhoff's law. As described above, if the feedback signal provided by the current source circuit is Id and the reference voltage of the boost module is denoted as Vfb, vfb/r13+id= (Vo-Vfb)/R12 is known according to kirchhoff's law. According to the formula, the output voltage Vo of the boost module can be obtained based on the feedback signal, and the product of the voltage amplitude of the Vo and the audio signal and the amplification factor of the power amplifier is matched, so that the function of linear dynamic amplitude adjustment can be realized.

The embodiment of the application adopts a pure hardware circuit design to realize low-distortion high-efficiency high-speed dynamic adjustment of the power supply amplitude of the power amplifier, and solves the problem of low efficiency of the power amplifier under the condition of non-full power operation. Meanwhile, compared with the related technology of performing energy pre-estimation control on the feedback signal by adopting a software algorithm, the method solves the problems of low adjustment speed and poor efficiency. The audio processing circuit provided by the embodiment of the application can realize great efficiency improvement, and can improve the playing duration by more than 40% under specific conditions, thereby greatly prolonging the service duration of the portable audio playing equipment product.

Fig. 8 is a schematic structural diagram of an audio playing device according to an embodiment of the present application. The audio playback device 800 shown in fig. 8 may include an audio processing circuit 810 and a speaker 820, wherein the audio processing circuit 810 may be any of the audio processing circuits described previously.

And a speaker 820 electrically connected to the audio processing circuit for playing the audio signal output from the audio processing circuit.

Optionally, the audio processing circuit 810 may include: the audio power amplifier circuit is used for receiving an audio signal and amplifying the power of the audio signal; the amplitude detection circuit is an analog circuit and is used for detecting the amplitude of the audio signal to obtain a feedback signal used for representing the amplitude of the audio signal; and the power supply circuit is electrically connected with the audio power amplifier circuit and the amplitude detection circuit and is used for receiving the feedback signal from the amplitude detection circuit and adjusting the power supply voltage of the audio power amplifier circuit according to the feedback signal so that the amplitude of the power supply voltage is matched with the amplitude of the audio signal.

Optionally, the amplitude detection circuit includes: a peak detection circuit for detecting a peak value of an amplitude of the audio signal; and the current source circuit is electrically connected with the peak detection circuit and is used for generating a current signal according to the detection result of the peak detection circuit and sending the current signal to the power supply circuit as the feedback signal.

Optionally, the peak detection circuit includes: a first operational amplifier; a first diode; a first resistor; a first capacitor.

Optionally, the current source circuit includes: a second operational amplifier; a metal oxide semiconductor field effect transistor; a second resistor; a third resistor; and a fourth resistor.

Optionally, the amplitude detection circuit further includes: and the amplitude adjusting circuit is electrically connected with the peak value detecting circuit and is used for receiving the input voltage of the audio signal and carrying out proportional adjustment on the voltage amplitude of the input voltage of the audio signal.

Optionally, the amplitude adjustment circuit includes: a third operational amplifier; a fifth resistor; a sixth resistor; and a second diode.

Optionally, the amplitude detection circuit further includes: the input end of the amplitude correction circuit is electrically connected with the peak detection circuit, the output end of the amplitude correction circuit is electrically connected with the current source circuit, and the amplitude correction circuit is used for correcting the voltage amplitude of the output voltage of the peak detection circuit.

Optionally, the amplitude correction circuit includes: a fourth operational amplifier; a seventh resistor; and an eighth resistor.

Optionally, the audio power amplifier circuit is a class D power amplifier circuit.

It should be understood that in the embodiments of the present application, "B corresponding to a" means that B is associated with a, from which B may be determined. It should also be understood that determining B from a does not mean determining B from a alone, but may also determine B from a and/or other information.

It should be understood that the term "and/or" is merely an association relationship describing the associated object, and means that three relationships may exist, for example, a and/or B may mean: a exists alone, A and B exist together, and B exists alone. In addition, the character "/" herein generally indicates that the front and rear associated objects are an "or" relationship.

It should be understood that, in various embodiments of the present application, the sequence numbers of the foregoing processes do not mean the order of execution, and the order of execution of the processes should be determined by the functions and internal logic thereof, and should not constitute any limitation on the implementation process of the embodiments of the present application.

In the several embodiments provided in this application, it should be understood that the disclosed systems and apparatuses may be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative, e.g., the division of the units is merely a logical function division, and there may be additional divisions when actually implemented, e.g., multiple units or components may be combined or integrated into another system, or some features may be omitted or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or units, which may be in electrical, mechanical or other form.

The units described as separate units may or may not be physically separate, and units shown as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional unit in each embodiment of the present application may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit.

In the above embodiments, it may be implemented in whole or in part by software, hardware, firmware, or any combination thereof. When implemented in software, may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When loaded and executed on a computer, produces a flow or function in accordance with embodiments of the present application, in whole or in part. The computer may be a general purpose computer, a special purpose computer, a computer network, or other programmable apparatus. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center by a wired (e.g., coaxial cable, fiber optic, digital subscriber line (digital subscriber Line, DSL)) or wireless (e.g., infrared, wireless, microwave, etc.). The computer readable storage medium may be any available medium that can be read by a computer or a data storage device such as a server, data center, etc. that contains an integration of one or more available media. The usable medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a magnetic tape), an optical medium (e.g., a digital versatile disk (digital video disc, DVD)), or a semiconductor medium (e.g., a Solid State Disk (SSD)), or the like.

The foregoing is merely specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily think about changes or substitutions within the technical scope of the present application, and the changes and substitutions are intended to be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims (10)

1. An audio processing circuit, comprising:

the audio power amplifier circuit is used for receiving an audio signal and amplifying the power of the audio signal;

the amplitude detection circuit is an analog circuit and is used for detecting the amplitude of the audio signal to obtain a feedback signal used for representing the amplitude of the audio signal;

and the power supply circuit is electrically connected with the audio power amplifier circuit and the amplitude detection circuit and is used for receiving the feedback signal from the amplitude detection circuit and adjusting the power supply voltage of the audio power amplifier circuit according to the feedback signal so that the amplitude of the power supply voltage is matched with the amplitude of the audio signal.

2. The audio processing circuit of claim 1, wherein the amplitude detection circuit comprises:

a peak detection circuit for detecting a peak value of an amplitude of the audio signal;

and the current source circuit is electrically connected with the peak detection circuit and is used for generating a current signal according to the detection result of the peak detection circuit and sending the current signal to the power supply circuit as the feedback signal.

3. The audio processing circuit of claim 2, wherein the peak detection circuit comprises: a first operational amplifier; a first diode; a first resistor; a first capacitor.

4. The audio processing circuit of claim 2, wherein the current source circuit comprises: a second operational amplifier; a metal oxide semiconductor field effect transistor; a second resistor; a third resistor; and a fourth resistor.

5. The audio processing circuit of claim 2, wherein the amplitude detection circuit further comprises:

and the amplitude adjusting circuit is electrically connected with the peak value detecting circuit and is used for receiving the input voltage of the audio signal and carrying out proportional adjustment on the voltage amplitude of the input voltage of the audio signal.

6. The audio processing circuit of claim 5, the amplitude adjustment circuit comprising: a third operational amplifier; a fifth resistor; a sixth resistor; and a second diode.

7. The audio processing circuit according to claim 2 or 5, wherein the amplitude detection circuit further comprises:

the input end of the amplitude correction circuit is electrically connected with the peak detection circuit, the output end of the amplitude correction circuit is electrically connected with the current source circuit, and the amplitude correction circuit is used for correcting the voltage amplitude of the output voltage of the peak detection circuit.

8. The audio processing circuit of claim 7, wherein the amplitude correction circuit comprises: a fourth operational amplifier; a seventh resistor; and an eighth resistor.

9. The audio processing circuit of claim 1, wherein the audio power amplifier circuit is a class D power amplifier circuit.

10. An audio playback device, comprising:

the audio processing circuit of any of claims 1-9; and

and the loudspeaker is electrically connected with the audio processing circuit and is used for playing the audio signals output by the audio processing circuit.