Class-d power amplifier modulation method, circuit and class-d audio power amplifier with low power consumption and high performance

Abstract

The application relates to a low-power-consumption high-performance class-D power amplifier modulation method, a circuit and a class-D audio power amplifier, and the method comprises the following steps: separating a pair of BD mode modulated signals output by a PWM modulation module in a class-D audio power amplifier circuit into common mode components and differential mode components, and outputting the common mode components and the differential mode components; feeding back the common mode components and the differential mode components to differential input ends through common mode feedback links and differential mode feedback links respectively; wherein the common mode components are completely made in a chip with the common mode feedback links; the differential mode components are realized with power MOSFETs integrated in the chip or external power MOSFETs; and the differential mode components are output to a to-be-driven object through a power output stage. After the two feedback links are separated, no common mode signal is sent to the output stage for amplification in a mute state with zero input, so that power consumption is not caused in the output stage, and thus the overall efficiency is greatly improved; meanwhile, static bottom noise is almost eliminated.

Description

Technical Field

[0001] This invention belongs to the field of integrated circuit design technology, and relates to a low-power, high-performance Class D power amplifier modulation method, circuit, and Class D audio power amplifier. Background Technology

[0002] In Class D closed-loop audio power amplifier circuits, AD and BD are the most basic and commonly used modulation modes. To further improve efficiency, especially under light load conditions, many products have begun to adopt improved AD or BD modulation modes in recent years. The main idea behind this is:

[0003] When outputting a small signal, maintain differential output while dynamically adjusting the common-mode voltage to minimize it, thereby reducing inductor ripple current and conduction losses in the switching transistor and inductor under such conditions.

[0004] When a large signal is output, it enters a single-sided switching mode and no longer maintains differential output. At this time, the P terminal is activated during the positive half-cycle of the output signal, and the N terminal is activated during the negative half-cycle of the output signal; only one side of the P or N terminal is activated. Therefore, when a large signal is output, the switching loss can be reduced by about half compared to the BD modulation mode.

[0005] However, even in such improved modulation modes, the output stage still needs to maintain a certain common-mode voltage during small-signal output to provide the voltage feedback signal required for closed-loop control. Summary of the Invention

[0006] To address the problems existing in the above-mentioned traditional methods, this invention proposes a low-power, high-performance Class D power amplifier modulation method, circuit, and Class D audio power amplifier, which can reduce losses and improve efficiency, reduce output noise in idle state, and completely eliminate the common "pop" noise caused by the differential bias of the audio power amplifier when the output stage is turned on.

[0007] To achieve the above objectives, the embodiments of the present invention adopt the following technical solutions:

[0008] On the one hand, a low-power, high-performance Class D power amplifier modulation method is provided, the method comprising the following steps:

[0009] The pair of BD-modulated signals output from the PWM modulation module in the Class D audio power amplifier circuit are separated into common-mode and differential-mode components, and the common-mode and differential-mode components are output.

[0010] The common-mode component and the differential-mode component are fed back to the differential input terminal through the common-mode feedback link and the differential-mode feedback link, respectively; the common-mode component and the common-mode feedback link are completely integrated inside the chip; the differential-mode component and the differential-mode feedback link are implemented using the power MOSFET integrated inside the chip or an external power MOSFET.

[0011] The differential mode component is output to the object to be driven through the power output stage.

[0012] In one embodiment, the pair of BD-modulated signals output by the PWM modulation module in the Class D audio power amplifier circuit includes: a PWM_P signal and a PWM_N signal.

[0013] The pair of BD-modulated signals output from the PWM modulation module in the Class D audio power amplifier circuit are separated into common-mode and differential-mode components, and the common-mode and differential-mode components are output, including:

[0014] The PWM_P and PWM_N signals are processed by an XOR gate and then logically ANDed with the PWM_P and PWM_N signals respectively to output the differential mode component.

[0015] Perform a logical AND operation on the PWM_P and PWM_N signals to output the common-mode component.

[0016] In one embodiment, the common-mode feedback link includes two common-mode feedback loops; wherein each common-mode feedback loop includes a complementary push-pull circuit composed of MOSFETs and a first resistor; the complementary push-pull circuit composed of MOSFETs is used to amplify the common-mode components; the common-mode components include PWM_P_CM components and PWM_N_CM components; feeding the common-mode components back to the differential input terminal through the common-mode feedback link includes:

[0017] The PWM_P_CM component and the PWM_N_CM component are fed back to the non-inverting input and the inverting input of the differential input terminal through the first common-mode feedback loop and the second common-mode feedback loop, respectively.

[0018] In one embodiment, the differential feedback link includes two differential feedback loops; wherein each differential feedback loop includes a power amplifier circuit and a second resistor; the differential components include PWM_P_DIFF components and PWM_N_DIFF components; feeding the differential components back to the differential input terminal through the differential feedback link includes:

[0019] The PWM_P_DIFF and PWM_N_DIFF components are fed back to the non-inverting and inverting input terminals of the differential input terminal through the first and second differential feedback loops, respectively.

[0020] On the other hand, a low-power, high-performance Class D power amplifier modulation circuit is also provided, comprising:

[0021] The differential input module is used to amplify, filter, and adjust the gain of the differential audio signal at the input terminal of the differential input module to obtain an intermediate signal in differential form; and transmit the intermediate signal to the PWM modulation module.

[0022] The PWM modulation module is used to perform PWM modulation on the received intermediate signal to obtain the PWM_P signal and the PWM_N signal.

[0023] The PWM logic processing module is used to separate the PWM_P signal and the PWM_N signal into common-mode component and differential-mode component using combinational logic circuits, and output the common-mode component and differential-mode component.

[0024] The common-mode feedback link is used to amplify the common-mode component and feed it back to the input of the differential input module; the common-mode component and the common-mode feedback link are completely integrated inside the chip.

[0025] The differential-mode feedback link is used to amplify the differential-mode component and feed it back to the input terminal of the differential input module; the differential-mode component and differential-mode feedback link are implemented using power MOSFETs integrated inside the chip or external power MOSFETs.

[0026] The power output stage is used to amplify and filter the differential-mode components and transmit the processed audio signal to the object to be driven.

[0027] In one embodiment, the PWM logic processing module includes: three AND gates and one XOR gate; the common-mode components include: PWM_P_CM signal and PWM_N_CM signal; the differential-mode components include: PWM_P_DIFF signal and PWM_N_DIFF signal.

[0028] The two inputs of the XOR gate receive the PWM_P and PWM_N signals, respectively. The output of the XOR gate is input to one input of the second AND gate and the third AND gate, respectively. The other input of the second AND gate and the third AND gate receive the PWM_P and PWM_N signals, respectively. The outputs of the second AND gate and the third AND gate output the PWM_P_DIFF and PWM_N_DIFF signals, respectively.

[0029] The two inputs of the first AND gate receive the PWM_P signal and the PWM_N signal, and the output of the first AND gate outputs the PWM_P_CM signal and the PWM_N_CM signal.

[0030] In one embodiment, the common-mode feedback link includes two common-mode feedback loops; wherein the common-mode feedback loop includes a common-mode drive module and a first resistor; the common-mode drive module includes a complementary push-pull circuit composed of MOSFETs.

[0031] In the first common-mode feedback loop: the PWM_P_CM signal is amplified by the common-mode drive module and then fed back to the non-inverting input terminal of the differential input module after passing through the first resistor.

[0032] In the second common-mode feedback loop: the PWM_N_CM signal is amplified by the common-mode drive module and then fed back to the inverting input terminal of the differential input module after passing through the first resistor.

[0033] In one embodiment, the differential feedback link includes two differential feedback loops; each differential feedback loop includes a power amplifier module and a second resistor; the power amplifier module includes a complementary push-pull circuit composed of MOSFETs.

[0034] In the first differential feedback loop: the PWM_P_DIFF signal is amplified by the power amplifier module and then fed back to the non-inverting input terminal of the differential input module after passing through the second resistor.

[0035] In the second differential feedback loop: the PWM_N_DIFF signal is amplified by the power amplifier module and then fed back to the inverting input terminal of the differential input module after passing through the second resistor.

[0036] In one embodiment, the PWM modulation module includes a ramp generator and two comparators.

[0037] The ramp generator is used to generate a high-frequency triangular carrier wave, which is then transmitted to the inverting inputs of two comparators.

[0038] The differential input module outputs a differential intermediate signal, which is then input to the non-inverting inputs of the two comparators.

[0039] On the other hand, a Class D audio amplifier is also provided, which includes any of the aforementioned low-power, high-performance Class D amplifier modulation circuits.

[0040] One of the above technical solutions has the following advantages and beneficial effects:

[0041] The aforementioned low-power, high-performance Class D power amplifier modulation method, circuit, and Class D audio power amplifier include the following steps: separating a pair of BD-modulated signals output from the PWM modulation module in the Class D audio power amplifier circuit into common-mode and differential-mode components, outputting common-mode and differential-mode components; feeding the common-mode and differential-mode components back to the differential input terminal via common-mode and differential-mode feedback links, respectively; wherein the common-mode component and common-mode feedback link are entirely integrated within the chip; the differential-mode component and differential-mode feedback link are implemented using integrated power MOSFETs or external power MOSFETs; and outputting the differential-mode component to the driven object through a power output stage. By separating the two feedback links, in a zero-input mute state, no common-mode signal is sent to the output stage for amplification, thus avoiding power consumption at the output stage and significantly improving overall efficiency; simultaneously, it almost eliminates static noise. Attached Figure Description

[0042] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0043] Figure 1 This is a flowchart illustrating a low-power, high-performance Class D power amplifier modulation method in one embodiment.

[0044] Figure 2 This is a block diagram of a low-power, high-performance Class D power amplifier modulation circuit in one embodiment;

[0045] Figure 3 This is a block diagram of the PWM logic processing module in one embodiment;

[0046] Figure 4 This is a schematic diagram of a traditional solution;

[0047] Figure 5 This is a schematic diagram of a traditional BD modulation mode waveform;

[0048] Figure 6 This is a waveform diagram of the fully differential output modulation mode of a low-power, high-performance Class D power amplifier modulation circuit in one embodiment. Detailed Implementation

[0049] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0050] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0051] It should be noted that, in this document, the reference to "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of the invention. The presentation of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art will understand that the embodiments described herein can be combined with other embodiments. The term "and / or" as used herein refers to any combination of one or more of the associated listed items, and all possible combinations, including such combinations.

[0052] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0053] In one embodiment, such as Figure 1 As shown, a low-power, high-performance Class D power amplifier modulation method is provided, which may include the following processing steps 100 to 102:

[0054] Step 100: Separate the pair of BD-modulated signals output by the PWM modulation module in the Class D audio power amplifier circuit into common-mode and differential-mode components, and output the common-mode and differential-mode components.

[0055] Specifically, this method is an improvement on the traditional Class D power amplifier modulation scheme, which includes: a differential input module, a PWM modulation module, a power amplification module, and an output terminal; the feedback path from the output of the power amplification module to the differential input module forms a feedback loop.

[0056] The pair of BD-modulated signals output by the PWM modulation module are differential audio signals that have been amplified in two stages by the differential input module and then PWM-modulated to obtain PWM signals, which include PWM_P and PWM_N signals.

[0057] A logic combination circuit is used to separate the PWM_P signal and the PWM_N signal into common-mode component and differential-mode component, and output the common-mode component and differential-mode component.

[0058] Step 101: The common-mode component and the differential-mode component are fed back to the differential input terminal through the common-mode feedback link and the differential-mode feedback link, respectively; the common-mode component and the common-mode feedback link are completely integrated inside the chip; the differential-mode component and the differential-mode feedback link are implemented by the power MOSFET integrated inside the chip or by an external power MOSFET.

[0059] Specifically, the common-mode feedback link and differential-mode feedback link are separated throughout the signal chain. The common-mode output and feedback links are entirely integrated within the chip; the differential-mode output and feedback are implemented using power MOSFETs integrated within the chip or external power MOSFETs. This new approach offers three advantages (significant improvements over current mainstream products in the industry in the following three key parameters of Class D audio amplifiers):

[0060] (1) Since the losses of Class D audio power amplifier circuit mainly come from the switching and conduction losses on the power MOSFET, as well as the losses caused by the output current and its ripple current in the peripheral LC filter, separating the two feedback links will prevent the common-mode part from causing power consumption in the output stage, thereby greatly improving the overall efficiency.

[0061] (2) When there is zero input, the power stage does not need to maintain the output, the two ends of the speaker are shorted, and the differential output is 0. Therefore, extremely low noise floor (<5uVrms) can be achieved, resulting in a better listening experience. The noise floor of mainstream products is about 30~200uVrms, and some high-performance products can reach 10~20uVrms.

[0062] (3) Elimination of power-on "pop" noise. In previous similar products, due to the small bias voltage between the P and N terminals, during the establishment of the common-mode voltage across the speaker after power-on, this bias leads to the generation of differential-mode signals, which manifests as "pop" noise at the speaker output. The solution proposed in this invention eliminates the common-mode component in the speaker output, thus completely eliminating the common "pop" noise caused by the differential bias of the audio power amplifier.

[0063] Step 102: The differential mode component is output to the object to be driven through the power output stage.

[0064] Specifically, the object to be driven is typically a loudspeaker. The power output stage is commonly composed of MOSFETs.

[0065] The aforementioned low-power, high-performance Class D power amplifier modulation method includes: separating a pair of BD-modulated signals output from the PWM modulation module in a Class D audio power amplifier circuit into common-mode and differential-mode components, outputting common-mode and differential-mode components; feeding the common-mode and differential-mode components back to the differential input terminal via common-mode and differential-mode feedback links, respectively; wherein the common-mode component and common-mode feedback link are entirely integrated within the chip; the differential-mode component and differential-mode feedback link are implemented using integrated power MOSFETs or external power MOSFETs; and outputting the differential-mode component to the driven object through a power output stage. By separating the two feedback links, this method ensures that in a zero-input mute state, no common-mode signal is sent to the output stage for amplification, thus preventing power consumption at the output stage and significantly improving overall efficiency; simultaneously, it almost eliminates static noise.

[0066] In one embodiment, the pair of BD-modulated signals output by the PWM modulation module in the Class D audio power amplifier circuit includes: a PWM_P signal and a PWM_N signal; Step 100 includes: processing the PWM_P signal and the PWM_N signal through an XOR gate and then performing a logical AND operation with the PWM_P signal and the PWM_N signal respectively to output a differential-mode component; performing a logical AND operation with the PWM_P signal and the PWM_N signal to output a common-mode component.

[0067] In one embodiment, the common-mode feedback link includes two common-mode feedback loops; wherein the common-mode feedback loop includes a complementary push-pull circuit composed of MOSFETs and a first resistor; the complementary push-pull circuit composed of MOSFETs is used to amplify the common-mode components; the common-mode components include PWM_P_CM components and PWM_N_CM components; step 101, feeding the common-mode components back to the differential input terminal through the common-mode feedback link, includes: feeding the PWM_P_CM components and PWM_N_CM components back to the non-inverting input terminal and the inverting input terminal of the differential input terminal through the first common-mode feedback loop and the second common-mode feedback loop, respectively.

[0068] In one embodiment, the differential feedback link includes two differential feedback loops; wherein the differential feedback loop includes a power amplifier circuit and a second resistor; the differential components include PWM_P_DIFF components and PWM_N_DIFF components; step 101, feeding the differential components to the differential input terminal through the differential feedback link, includes: feeding the PWM_P_DIFF components and PWM_N_DIFF components to the non-inverting input terminal and the inverting input terminal of the differential input terminal through the first differential feedback loop and the second differential feedback loop, respectively.

[0069] It should be understood that, although the above Figure 1 The steps are shown sequentially as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise explicitly stated in this document, there is no strict order in which these steps are executed; they can be performed in other orders. Furthermore, the above... Figure 1 At least some of the steps may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least some of the sub-steps or stages of other steps.

[0070] In one embodiment, such as Figure 2 As shown, a low-power, high-performance Class D power amplifier modulation circuit is also provided, comprising:

[0071] The differential input module is used to amplify, filter, and adjust the gain of the differential audio signal at the input terminal of the differential input module to obtain an intermediate signal in differential form; and transmit the intermediate signal to the PWM modulation module.

[0072] The PWM modulation module is used to perform PWM modulation on the received intermediate signal to obtain the PWM_P signal and the PWM_N signal.

[0073] The PWM logic processing module is used to separate the PWM_P signal and the PWM_N signal into common-mode component and differential-mode component using combinational logic circuits, and output the common-mode component and differential-mode component.

[0074] The common-mode feedback link is used to amplify the common-mode component and feed it back to the input of the differential input module; the common-mode component and the common-mode feedback link are completely integrated inside the chip.

[0075] The differential-mode feedback link is used to amplify the differential-mode component and feed it back to the input terminal of the differential input module; the differential-mode component and differential-mode feedback link are implemented using power MOSFETs integrated inside the chip or external power MOSFETs.

[0076] The power output stage is used to amplify and filter the differential-mode components and transmit the processed audio signal to the object to be driven.

[0077] In one embodiment, the PWM logic processing module includes: three AND gates and one XOR gate; the common-mode components include: PWM_P_CM signal and PWM_N_CM signal; the differential-mode components include: PWM_P_DIFF signal and PWM_N_DIFF signal.

[0078] The two inputs of the XOR gate receive the PWM_P and PWM_N signals, respectively. The output of the XOR gate is input to one input of the second AND gate and the third AND gate, respectively. The other input of the second AND gate and the third AND gate receive the PWM_P and PWM_N signals, respectively. The outputs of the second AND gate and the third AND gate output the PWM_P_DIFF and PWM_N_DIFF signals, respectively.

[0079] The two inputs of the first AND gate receive the PWM_P signal and the PWM_N signal, and the output of the first AND gate outputs the PWM_P_CM signal and the PWM_N_CM signal.

[0080] Specifically, the PWM logic processing module separates the common-mode and differential-mode components of the BD-modulated signals PWM_P and PWM_N output from the PWM modulator, outputting the common-mode components PWM_P_CM and PWM_N_CM, and the differential-mode components PWM_P_DIFF and PWM_N_DIFF. This module is entirely implemented using combinational logic; one specific implementation is as follows: Figure 3The input signals PWM_P and PWM_N are XORed by gate XOR1 to obtain the differential-mode components. These components are then ANDed with the input signals PWM_P and PWM_N through AND gates AND2 and AND3 respectively, achieving the effect of retaining only the differential-mode components in the original signals and outputting them. Simultaneously, the input signals PWM_P and PWM_N are ANDed by gate AND1 to obtain the common-mode components, which are then output. Here, PWM_P_CM and PWM_N_CM are identical signals.

[0081] In one embodiment, the common-mode feedback link includes two common-mode feedback loops; wherein each common-mode feedback loop includes a common-mode drive module and a first resistor; the common-mode drive module includes a complementary push-pull circuit composed of MOS transistors; in the first common-mode feedback loop: the PWM_P_CM signal is amplified by the common-mode drive module U1 and then fed back to the non-inverting input terminal of the differential input module after passing through the first resistor R1; in the second common-mode feedback loop: the PWM_N_CM signal is amplified by the common-mode drive module U2 and then fed back to the inverting input terminal of the differential input module after passing through the first resistor R2.

[0082] In one embodiment, the differential feedback link includes two differential feedback loops; each differential feedback loop includes a power amplifier module and a second resistor; the power amplifier module includes a complementary push-pull circuit composed of MOSFETs; in the first differential feedback loop: the PWM_P_DIFF signal is amplified by the power amplifier module U3 and then fed back to the non-inverting input terminal of the differential input module after passing through the second resistor R3; in the second differential feedback loop: the PWM_N_DIFF signal is amplified by the power amplifier module U4 and then fed back to the inverting input terminal of the differential input module after passing through the second resistor R4.

[0083] The power amplifier module is essentially a complementary push-pull MOSFET, providing voltage and current amplification. The feedback loop sends the amplified signal back to the analog signal input node through a feedback resistor network. This analog signal input node is located relatively early, at the modulator's entry point. The modulator's function is to convert the analog signal into PWM_P and PWM_N signals.

[0084] In addition, the feedback resistor networks for common mode and differential mode are exactly the same, and the amplification factor is consistent.

[0085] In one embodiment, the PWM modulation module includes a ramp generator and two comparators.

[0086] The ramp generator is used to generate a high-frequency triangular carrier wave, which is then transmitted to the inverting inputs of two comparators.

[0087] The differential input module outputs a differential intermediate signal, which is then input to the non-inverting inputs of the two comparators.

[0088] In one specific embodiment, the low-power, high-performance Class D power amplifier modulation circuit proposed in the application is combined with, as shown in the example... Figure 4 The traditional scheme shown is compared.

[0089] Figure 5 This is a traditional BD modulation waveform. OUT_BD is the output signal of the traditional BD modulation process, and OUTP_BD and OUTN_BD are the two ends of the differential output. It can be seen that regardless of the output amplitude, both ends always maintain PWM output, but the differential signal is output in a differential manner with a 50% duty cycle as the center.

[0090] Figure 6 The waveforms shown are those of the fully differential output modulation mode of the low-power, high-performance Class D power amplifier modulation circuit proposed in this application. OUTP and OUTN are the signals actually sent to the output stage, while OUTCMP and OUTCMN are internal common-mode biases and are not sent to the output stage. It can be seen that compared with the traditional BD modulation method, when there is an output signal OUT, the number of switches on the output stage is reduced by half. In the zero-input mute state, all switching actions are eliminated, which greatly reduces the switching losses of the power stage.

[0091] A Class D audio amplifier, comprising any of the aforementioned low-power, high-performance Class D amplifier modulation circuits.

[0092] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0093] The above embodiments are merely illustrative of several implementation methods of this application, and their descriptions are relatively specific and detailed. However, they should not be construed as limiting the scope of protection of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and all such modifications and improvements fall within the scope of protection of this application.

Claims

1. A low-power, high-performance Class D power amplifier modulation method, characterized in that, Including the following steps: In a Class D audio power amplifier circuit, the pair of BD-modulated signals output by the PWM modulation module are separated into common-mode and differential-mode components, and the common-mode and differential-mode components are output. The common-mode component and the differential-mode component are respectively fed back to the differential input terminal through the common-mode feedback link and the differential-mode feedback link; The common-mode component and the common-mode feedback link are entirely integrated inside the chip; the differential-mode component and the differential-mode feedback link are implemented using power MOSFETs integrated inside the chip or external power MOSFETs. The differential mode component is output to the object to be driven through the power output stage.

2. The low-power, high-performance Class D power amplifier modulation method according to claim 1, characterized in that, In a Class D audio power amplifier circuit, the pair of BD-modulated signals output by the PWM modulation module include: PWM_P signal and PWM_N signal; The pair of BD-modulated signals output from the PWM modulation module in the Class D audio power amplifier circuit are separated into common-mode and differential-mode components, and the common-mode and differential-mode components are output, including: The PWM_P and PWM_N signals are processed by an XOR gate and then logically ANDed with the PWM_P and PWM_N signals respectively to output the differential mode component. Perform a logical AND operation on the PWM_P and PWM_N signals to output the common-mode component.

3. The low-power, high-performance Class D power amplifier modulation method according to claim 1, characterized in that, The common-mode feedback link includes two common-mode feedback loops; wherein each common-mode feedback loop includes a complementary push-pull circuit composed of MOS transistors and a first resistor; the complementary push-pull circuit composed of MOS transistors is used to amplify the common-mode component; The common-mode components include PWM_P_CM components and PWM_N_CM components; Feeding the common-mode component back to the differential input via a common-mode feedback link includes: The PWM_P_CM component and the PWM_N_CM component are fed back to the non-inverting input and the inverting input of the differential input terminal through the first common-mode feedback loop and the second common-mode feedback loop, respectively.

4. The low-power, high-performance Class D power amplifier modulation method according to claim 1, characterized in that, The differential mode feedback link includes two differential mode feedback loops; wherein each differential mode feedback loop includes a power amplifier circuit and a second resistor; The differential mode components include PWM_P_DIFF components and PWM_N_DIFF components; The differential component is fed back to the differential input terminal via a differential feedback link, including: The PWM_P_DIFF component and the PWM_N_DIFF component are fed back to the non-inverting input and the inverting input of the differential input terminal through the first differential feedback loop and the second differential feedback loop, respectively.

5. A low-power, high-performance Class D power amplifier modulation circuit, characterized in that, include: The differential input module is used to amplify, filter, and adjust the gain of the differential audio signal at the input terminal of the differential input module to obtain an intermediate signal in differential form; and transmit the intermediate signal to the PWM modulation module. The PWM modulation module is used to perform PWM modulation on the received intermediate signal to obtain PWM_P signal and PWM_N signal; The PWM logic processing module is used to separate the PWM_P signal and the PWM_N signal into common-mode component and differential-mode component using combinational logic circuits, and output the common-mode component and differential-mode component. A common-mode feedback link is used to amplify the common-mode component and feed it back to the input terminal of the differential input module; the common-mode component and the common-mode feedback link are completely integrated inside the chip; A differential-mode feedback link is used to amplify the differential-mode component and feed it back to the input terminal of the differential input module; the differential-mode component and the differential-mode feedback link are implemented using a power MOSFET integrated inside the chip or an external power MOSFET; The power output stage is used to amplify and filter the differential-mode components and transmit the processed audio signal to the object to be driven.

6. The low-power, high-performance Class D power amplifier modulation circuit according to claim 5, characterized in that, The PWM logic processing module includes: three AND gates and one XOR gate; the common-mode components include: PWM_P_CM signal and PWM_N_CM signal; the differential-mode components include: PWM_P_DIFF signal and PWM_N_DIFF signal; The two input terminals of the XOR gate receive the PWM_P signal and the PWM_N signal, and the output of the XOR gate is respectively input to one input terminal of the second AND gate and the third AND gate. The other input terminal of the second AND gate and the third AND gate respectively receive the PWM_P signal and the PWM_N signal. The output terminals of the second AND gate and the third AND gate respectively output the PWM_P_DIFF signal and the PWM_N_DIFF signal. The two inputs of the first AND gate receive the PWM_P signal and the PWM_N signal, and the output of the first AND gate outputs the PWM_P_CM signal and the PWM_N_CM signal.

7. The low-power, high-performance Class D power amplifier modulation circuit according to claim 5, characterized in that, The common-mode feedback link includes two common-mode feedback loops; wherein each common-mode feedback loop includes a common-mode drive module and a first resistor; the common-mode drive module includes a complementary push-pull circuit composed of MOS transistors; In the first common-mode feedback loop: the PWM_P_CM signal is amplified by the common-mode drive module and then fed back to the non-inverting input terminal of the differential input module after passing through the first resistor; In the second common-mode feedback loop: the PWM_N_CM signal is amplified by the common-mode drive module and then fed back to the inverting input terminal of the differential input module after passing through the first resistor.

8. The low-power, high-performance Class D power amplifier modulation circuit according to claim 5, characterized in that, The differential mode feedback link includes two differential mode feedback loops; each differential mode feedback loop includes a power amplifier module and a second resistor; the power amplifier module includes a complementary push-pull circuit composed of MOSFETs. In the first differential feedback loop: the PWM_P_DIFF signal is amplified by the power amplifier module and then fed back to the inverting input terminal of the differential input module after passing through the second resistor; In the second differential feedback loop: the PWM_N_DIFF signal is amplified by the power amplifier module and then fed back to the inverting input terminal of the differential input module after passing through the second resistor.

9. The low-power, high-performance Class D power amplifier modulation circuit according to claim 5, characterized in that, The PWM modulation module includes: a ramp generator and two comparators; The ramp generator is used to generate a high-frequency triangular carrier wave and transmit it to the inverting inputs of two comparators; The differential input module outputs a differential intermediate signal, which is then input to the non-inverting inputs of the two comparators.

10. A Class D audio power amplifier, characterized in that, The Class D audio amplifier includes the low-power, high-performance Class D amplifier modulation circuit as described in any one of claims 5 to 9.

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