Class-D power amplifier circuit, class-D power amplifier and audio equipment
By introducing a flow leakage circuit and energy storage circuit into the Class D power amplifier circuit, the energy loss problem caused by reverse current during the alternating conduction of Class D power amplifier circuit is solved, and the reuse of electrical energy is realized and the accumulation of heat is reduced. and improve equipment performance.
Patent Information
- Application Number
- CN202411327805.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-23
- Publication Date
- 2024-12-27
AI Technical Summary
Class D power amplifier circuits generate reverse current during the alternating conduction process, resulting in large energy loss and heat accumulation. In the prior art, diodes are used to leak flow, but there are still energy loss problems.
Design a Class D power amplifier circuit, including amplifier circuit, current leakage circuit and energy storage circuit. The amplifier circuit alternately conducts and cuts off to generate pulse current. The current leakage circuit is used to discharge reverse current. The energy storage circuit stores and reuses electrical energy. , reduce energy loss.
By reusing electrical energy, the energy loss of audio equipment is reduced, the heat accumulation is reduced, and the performance and service life of Class D power amplifiers are improved.
Smart Images
Figure CN119210371A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of power amplification, and in particular to a class D power amplifier circuit, a class D power amplifier and an audio device. Background Art
[0002] With the continuous advancement of Class D audio amplifier technology, its output power has been significantly improved and the operating frequency has also been increasing. However, the inductor current cannot change instantaneously. When the power tube is alternately turned on, the current in the inductor tries to maintain continuity, thus forming a reverse current in a short time. This phenomenon not only causes additional energy loss in the circuit, but also generates unnecessary heat accumulation.
[0003] Currently, diodes are used in circuits to discharge reverse currents to reduce the impact of reverse currents on the circuits. However, the class D power amplifier circuits in the prior art have the problem of large energy loss. Summary of the invention
[0004] The main purpose of the present invention is to provide a class D power amplifier circuit, a class D power amplifier and an audio device, aiming to reduce the energy loss of the audio device.
[0005] To achieve the above object, the present invention provides a class D power amplifier circuit, the class D power amplifier circuit comprising:
[0006] First inductor;
[0007] an amplifier circuit, the amplifier circuit being connected to the first end of the first inductor, the amplifier circuit being alternately turned on and off within a preset frequency to generate a pulse current, the pulse current flowing to the first inductor;
[0008] A leakage circuit, the leakage circuit being arranged in parallel with the amplifying circuit; the leakage circuit being used to discharge the current flowing through the amplifying circuit after the amplifying circuit is cut off;
[0009] An energy storage circuit is electrically connected to the leakage circuit and the amplifier circuit, and is used to receive and store the electric energy output by the leakage circuit.
[0010] Optionally, the energy storage circuit is also used to release the electric energy; when the amplifying circuit is in an on state, the energy storage circuit releases the electric energy so that the electric energy is at least a part of the pulse current and flows to the first inductor.
[0011] Optionally, the amplifier circuit includes a first power tube and a second power tube, the source of the first power tube and the drain of the second power tube are connected to the first end of the first inductor; the drain of the first power tube is connected to the energy storage circuit, and the source of the second power tube is connected to the energy storage circuit.
[0012] Optionally, the leakage circuit includes:
[0013] a first fast recovery diode, arranged in parallel with the first power tube, wherein the cathode of the first fast recovery diode is connected to the drain of the first power tube, and the anode of the first fast recovery diode is connected to the source of the first power tube;
[0014] A second fast recovery diode is arranged in parallel with the second power tube, an anode of the second fast recovery diode is connected to the drain of the second power tube, and a cathode of the first fast recovery diode is connected to the source of the second power tube.
[0015] Optionally, the first power tube and / or the second power tube is a gallium nitride power tube;
[0016] And / or, the first fast recovery diode and / or the second fast recovery diode is a silicon carbide diode.
[0017] Optionally, the energy storage circuit includes:
[0018] A first energy storage capacitor, wherein a first end of the first energy storage capacitor is connected to a drain of the first power tube;
[0019] A second energy storage capacitor, wherein a first end of the second energy storage capacitor is connected to a source of the second power tube;
[0020] The second ends of the first energy storage capacitor and the second energy storage capacitor are grounded.
[0021] Optionally, the class D power amplifier circuit further includes a first power supply terminal and a second power supply terminal, and the amplifier circuit includes a first power tube, a second power tube and a controller;
[0022] The gates of the first power tube and the second power tube are connected to the controller; the source of the first power tube and the drain of the second power tube are connected to the first end of the first inductor; the drain of the first power tube is connected to the first power supply end, and the source of the second power tube is connected to the second power supply end.
[0023] Optionally, the class D power amplifier circuit further includes a third energy storage capacitor, one end of the third energy storage capacitor is connected to the second end of the first inductor, and the other end of the third energy storage capacitor is grounded;
[0024] The third energy storage capacitor is used to receive and store at least a portion of the electric energy output from the second end of the first inductor.
[0025] The present invention further provides a class D power amplifier, which includes the class D power amplifier circuit as described above.
[0026] The present invention further provides an audio device, comprising:
[0027] A class D amplifier circuit as described above; or
[0028] A class D power amplifier as described above.
[0029] The solution proposed in the present invention is to reduce the energy loss of audio equipment, and discloses a class D power amplifier circuit, which includes a first inductor, an amplifier circuit, a leakage circuit and an energy storage circuit; wherein the amplifier circuit and the leakage circuit are connected in parallel and are respectively connected to the first inductor and the energy storage circuit. When the amplifier circuit is working, the first transistor and the second transistor of the amplifier circuit are alternately turned on and off, and the inductor forms a reverse current in a short time; the reverse current flows into the energy storage circuit through the leakage circuit, and the energy storage circuit stores the electrical energy of the reverse current and reuses the electrical energy. In this way, the electrical energy of the class D power amplifier circuit of the present invention can be reused to reduce energy loss. BRIEF DESCRIPTION OF THE DRAWINGS
[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the prior art description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.
[0031] Figure 1 A schematic diagram of an embodiment of a class D power amplifier circuit provided by the present invention;
[0032] Figure 2 A schematic diagram of an embodiment of a first state of a class D power amplifier circuit provided by the present invention;
[0033] Figure 3 A schematic diagram of an embodiment of a second state of a class D power amplifier circuit provided by the present invention;
[0034] Figure 4 A schematic diagram of a third state of an embodiment of a class D power amplifier circuit provided by the present invention;
[0035] Figure 5 It is a schematic diagram of an embodiment of a fourth state of a class D power amplifier circuit provided by the present invention.
[0036] Description of Figure Numbers:
[0037] 100. Class D power amplifier circuit; 1. Amplification circuit; 2. Current leakage circuit; 3. Energy storage circuit.
[0038] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION
[0039] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0040] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.
[0041] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.
[0042] With the continuous advancement of Class D audio amplifier technology, its output power has been significantly improved and the operating frequency has also been increasing. However, the inductor current cannot change instantaneously. When the power tube is alternately turned on, the current in the inductor tries to maintain continuity, thus forming a reverse current in a short time. This phenomenon not only causes additional energy loss in the circuit, but also generates unnecessary heat accumulation.
[0043] Currently, diodes are used in circuits to discharge reverse currents to reduce the impact of reverse currents on the circuits. However, the class D power amplifier circuits in the prior art have the problem of large energy loss.
[0044] In order to reduce the energy loss of a class D power amplifier, the present invention provides a class D power amplifier circuit 100, which can be used for a class D power amplifier or for an audio device; in this embodiment, Figure 1As shown, the class D power amplifier circuit 100 includes a first inductor L, an amplifier circuit 1, a leakage circuit 2 and an energy storage circuit 3. The amplifier circuit 1 is connected to the first end of the first inductor L, and the amplifier circuit 1 is alternately turned on and off within a preset frequency to generate a pulse current, and the pulse current flows to the first inductor L; the leakage circuit 2 is arranged in parallel with the amplifier circuit 1; the leakage circuit 2 is used to discharge the current flowing through the amplifier circuit 1 after the amplifier circuit 1 is turned off; the energy storage circuit 3 is electrically connected to the leakage circuit 2 and the amplifier circuit 1, and is used to receive and store the electric energy output by the leakage circuit.
[0045] It can be understood that after the amplifier circuit 1 is connected to the first end of the first inductor L, the amplifier circuit 1 is responsible for generating a signal, and the power tubes (which can be MOSFETs or other types of transistors) in the amplifier circuit 1 are alternately turned on and off at a preset frequency. When turned on, they allow current to flow from the power supply to the load and pass through the first inductor L; the role of the inductor is to smooth the current pulse, reduce high-frequency noise, and store magnetic field energy.
[0046] In addition, the above preset frequency refers to the frequency of the PWM (pulse width modulation) signal, which is the basis for the Class D amplifier to control the conduction and cutoff of the power tube. By adjusting the length of conduction time in each cycle, the output power can be changed, thereby controlling the volume of the speaker.
[0047] It is understandable that when the power tube switches from the on state to the off state, the magnetic field energy stored in the first inductor L will try to keep the current flowing, and the reverse current generated by the first inductor L can flow through the leakage circuit 2.
[0048] The leakage circuit 2 may be a parasitic diode located in the power tube, or may be an additional circuit connected in parallel with the amplifying circuit 1 .
[0049] It is understandable that the leakage circuit 2 is used to provide a channel for the reverse current in the first inductor L when the power tube is turned off, so as to avoid voltage spikes caused by sudden current interruption, as well as the resulting energy loss and circuit damage. Specifically, when the power tube of the class D amplifier switches from the on state to the off state under the control of the PWM signal, the current in the inductor will not stop immediately because the inductor has the characteristic of preventing sudden current changes. At this time, if there is no leakage circuit 2, the current in the inductor will be forced to be suddenly interrupted, which will generate a very high voltage spike in the circuit and may cause damage to the power tube. The leakage circuit 2 provides a low impedance path for the current, allowing the current in the inductor to flow back to the power supply or to the energy storage circuit 3 through the diode when the power tube is turned off, thereby avoiding the formation of voltage spikes.
[0050] It is understandable that the energy storage circuit 3 can be composed of capacitors. When the current flows to the energy storage circuit 3 through the leakage circuit 2, the capacitors will be charged to store the energy that would otherwise be wasted. When the amplifier circuit 1 is turned on again, these capacitors can release the previously stored energy to assist the main power supply in supplying current, thereby improving the efficiency of the entire system.
[0051] The combined use of the leakage circuit 2 and the energy storage circuit 3 can, on the one hand, discharge the reverse current through the leakage circuit 2 to avoid the reverse current from being unable to be released and damaging the power tube, thereby ensuring the service life of the class D power amplifier circuit 100; on the other hand, the reverse current output by the leakage circuit 2 can be reused through the energy storage circuit 3 to reduce the energy loss of the class D power amplifier circuit 100.
[0052] In practical applications, when the power tube in the amplifier circuit 1 is turned on under the control of the PWM signal, the current flows from the positive electrode of the power supply to the power tube, and then passes through the first inductor L. During this process, the first inductor L stores magnetic field energy; finally, the current reaches the load (such as a speaker) to complete the path of the forward working current. When the power tube switches from the on state to the off state under the control of the PWM signal, the magnetic field energy in the first inductor L attempts to maintain the continuity of the current. At this time, since the power tube has been turned off, the current cannot flow directly, so a reverse voltage is generated. The reverse current flows through the leakage circuit 2 to the energy storage circuit 3, which receives and passes through the diode or resistor from the leakage circuit 2. In this way, the entire circuit reduces energy loss, reduces heat generation, and improves the performance and service life of the Class D amplifier.
[0053] In summary, the solution proposed by the present invention is to reduce the energy loss of audio equipment, and discloses a class D power amplifier circuit 100, which includes a first inductor L, an amplifier circuit 1, a leakage circuit 2 and an energy storage circuit 3; when the amplifier circuit 1 is working, the transistor of the amplifier circuit 1 is alternately turned on and off, and the first inductor L forms a reverse current in a short time; the reverse current flows into the energy storage circuit 3 through the leakage circuit 2, and the energy storage circuit 3 stores the electric energy of the reverse current and reuses the electric energy. In this way, the electric energy of the class D power amplifier circuit 100 of the present invention can be reused to reduce energy loss, and at the same time, a path is provided for the reverse current to prevent the reverse current from damaging the power tube, thereby improving the service life of the class D power amplifier circuit 100.
[0054] Optionally, the energy storage circuit 3 is also used to release the electric energy; when the amplifier circuit 1 is in the on state, the energy storage circuit 3 releases the electric energy, so that the electric energy is at least a part of the pulse current and flows to the first inductor L.
[0055] It is understandable that when the leakage circuit 2 is turned on, the reverse current in the first inductor L will flow to the capacitor in the energy storage circuit 3, and the capacitor will start to charge and store this part of energy. When the power tube is turned on again and is ready to generate a new pulse current, the capacitor in the energy storage circuit 3 begins to release the previously stored energy. This part of energy, together with the energy provided by the power supply, constitutes a part of the pulse current flowing to the first inductor L. In other words, when the power tube is turned on, the capacitor acts as an auxiliary power supply to release the previously stored energy and enhance the current supply capacity of the main power supply. In this way, through such a design, the energy that may have been wasted in the power tube switching process is recovered and reused. The energy released by the capacitor can reduce the burden on the main power supply, reduce the overall power demand, thereby reducing energy loss and improving the efficiency of the circuit.
[0056] Optional, such as Figures 2 to 5 As shown, the amplifier circuit 1 includes a first power tube Q1 and a second power tube Q2, the source of the first power tube Q1 and the drain of the second power tube Q2 are connected to the first end of the first inductor L; the drain of the first power tube Q1 is connected to the energy storage circuit 3, and the source of the second power tube Q2 is connected to the energy storage circuit 3.
[0057] The first power tube Q1 and the second power tube Q2 can be MOSFET or BJT. The power tubes are alternately turned on and off in the circuit to form a pulse width modulation (PWM) signal to transmit the audio signal.
[0058] Optional, such as Figures 2 to 5 As shown, the leakage circuit 2 includes: a first fast recovery diode Q3 and a second fast recovery diode Q4, the first fast recovery diode Q3 is arranged in parallel with the first power tube Q1, the cathode of the first fast recovery diode Q3 is connected to the drain of the first power tube Q1, and the anode of the first fast recovery diode Q3 is connected to the source of the first power tube Q1; the second fast recovery diode Q4 is arranged in parallel with the second power tube Q2, the anode of the second fast recovery diode Q4 is connected to the drain of the second power tube Q2, and the cathode of the first fast recovery diode Q3 is connected to the source of the second power tube Q2.
[0059] Fast recovery diodes are diodes specially designed for high-frequency switching applications. They can recover from the forward conduction state to the reverse cutoff state in a very short time. Their purpose is to handle the reverse current generated at the moment of power tube (such as MOSFET) switching to avoid voltage spikes and energy loss.
[0060] Optionally, the first power tube Q1 and / or the second power tube Q2 is a gallium nitride (GaN) power tube; it can be understood that gallium nitride is a wide bandgap semiconductor material with high electron mobility and high breakdown electric field strength, which enables the gallium nitride power tube to withstand high voltage and large current while maintaining low on-resistance and fast switching speed.
[0061] When the power tube is GaN, the GaN power tube has extremely low on-resistance RDS(ON), tiny parasitic capacitance, low on-voltage and excellent thermal conductivity, which enables the amplifier to operate stably at a high switching frequency, reducing the physical size and capacitance of the required energy storage elements, thereby promoting the compactness and lightweight of the overall design.
[0062] Optionally, the first fast recovery diode Q3 and / or the second fast recovery diode Q4 is a silicon carbide diode. It is understandable that SiC is also a wide bandgap semiconductor material with a high critical breakdown electric field, high thermal conductivity, and high saturation electron drift velocity. This enables the SiC diode to switch quickly while withstanding high voltage and high current, and almost no loss is generated during the reverse recovery process.
[0063] When the diode is SiC, the SiC fast recovery diode has good reverse recovery characteristics and low forward conduction voltage reduction, which can quickly and effectively discharge the reverse current in the circuit, significantly reducing switching losses and alleviating the burden on the GaN power tube; more importantly, due to the reduction in the reverse recovery current of the SiC diode, the electromagnetic interference (EMI) generated by the amplifier during operation is significantly reduced, effectively reducing mutual interference between circuits; and this characteristic of the SiC diode can also suppress the overshoot of the PWM drive voltage, avoiding the generation of high-frequency noise and audio distortion, thereby optimizing the auditory experience of the amplifier and ensuring the purity and fidelity of the audio signal.
[0064] When GaN power tubes and SiC diodes are combined, the overall efficiency can be improved. GaN power tubes have high switching speeds and low on-resistance, which requires that the diodes used with them must also have fast switching capabilities. SiC diodes just meet this requirement. Their fast reverse recovery characteristics and low reverse recovery current enable them to quickly respond to the switching action of the GaN power tube, reduce switching losses, and improve overall efficiency.
[0065] Optional, such as Figures 2 to 5 As shown, the energy storage circuit 3 includes a first energy storage capacitor C1 and a second energy storage capacitor C2; the first end of the first energy storage capacitor C1 is connected to the drain of the first power tube Q1; the first end of the second energy storage capacitor C2 is connected to the source of the second power tube Q2; the second ends of the first energy storage capacitor C1 and the second energy storage capacitor C2 are grounded.
[0066] It can be understood that the first energy storage capacitor C1 and the second energy storage capacitor C2 receive and store the reverse current from the first inductor L. When the power tube is turned on again, the first energy storage capacitor C1 and the second energy storage capacitor C2 will release the previously stored energy, assist the main power supply to supply current, and enhance the current supply capacity of the main power supply, which can reduce the burden of the main power supply and reduce the overall power demand, thereby reducing energy loss and improving the efficiency of the circuit. At the same time, the first energy storage capacitor C1 and the second energy storage capacitor C2 can also smooth the fluctuations of the power supply voltage and provide a stable voltage platform, which is essential for maintaining the stable output of the amplifier.
[0067] Optionally, the Class D power amplifier circuit 100 also includes a first power supply terminal V1 and a second power supply terminal V2, and the amplifier circuit 1 includes a first power tube Q1, a second power tube Q2 and a controller U1; the gates of the first power tube Q1 and the second power tube Q2 are connected to the controller U1; the source of the first power tube Q1 and the drain of the second power tube Q2 are connected to the first end of the first inductor L; the drain of the first power tube Q1 is connected to the first power supply terminal V1, and the source of the second power tube Q2 is connected to the second power supply terminal V2.
[0068] The controller U1 is used to generate a PWM signal. By adjusting the duty cycle of the signal (i.e., the ratio of the on-time of the signal in each cycle to the total time), the controller U1 can finely control the power level output to the load. The controller U1 controls the gates of the first power tube Q1 and the second power tube Q2 through the PWM signal, thereby determining their on and off states. When the controller U1 sends a high-level signal to the gate of the power tube, the first power tube Q1 or the second power tube Q2 is turned on; when a low-level signal is sent, the first power tube Q1 and the second power tube Q2 are turned off.
[0069] Optional, such as Figures 2 to 5 As shown, the class D power amplifier circuit 100 also includes a third energy storage capacitor C3, one end of the third energy storage capacitor C3 is connected to the second end of the first inductor L, and the other end of the third energy storage capacitor C3 is grounded; the third energy storage capacitor C3 is used to receive and store at least part of the electric energy output from the second end of the first inductor L.
[0070] Optionally, the class D power amplifier circuit 100 further includes a first resistor R1 , one end of which is connected to the third energy storage capacitor R3 and the first inductor L, and the other end of which is grounded.
[0071] It can be understood that the present class D power amplifier circuit 100 includes four working states; first state: the first power tube Q1 is turned on, and the second power tube Q2 is turned off. Second state: the first power tube Q1 and the second power tube Q2 are both turned off. Third state: the second power tube Q2 is turned on, and the first power tube Q1 is turned off. Fourth state: the first power tube Q1 and the second power tube Q2 are both turned off.
[0072] The above four working states are a cycle, that is, from the first state to the second state to the third state to the fourth state and then back to the first state; and so on.
[0073] For the first state, Figure 2 As shown, the current passes through the first power tube Q1, then flows through the first inductor L, and then through the first energy storage capacitor C1 and the third energy storage capacitor C3, and finally reaches the ground. At this time, the first inductor L starts to store energy.
[0074] For the second state, Figure 3 As shown, when the first power tube Q1 turns from on to off, and the second power tube Q2 is not yet on, there will be a short dead time. During this time, the first power tube Q1 and the second power tube Q2 are both in the off state. Since the current of the first inductor L cannot drop to zero immediately, the current will flow back to the first inductor L through a path provided by the second fast recovery diode Q4, avoiding the voltage spike caused by the sudden interruption of the current. That is, the current forms a loop, and the current in the circuit flows from the first inductor L through the third energy storage capacitor C3 to the ground, and then returns to the first inductor L through the second fast recovery diode Q4.
[0075] For the third state, Figure 4 As shown, when the second power tube Q2 is turned on, the current starts from the third energy storage capacitor C3, passes through the first inductor L, and then flows to the ground through the second power tube Q2. The first inductor L continues to store energy, and the third energy storage capacitor C3 acts as an energy buffer to assist the continuity of the current.
[0076] For the fourth state, Figure 5 As shown, similar to the first dead time, when the second power tube Q2 changes from on to off, and the first power tube Q1 is not yet on, the current in the first inductor L cannot stop immediately. At this time, the current flows back to the power supply through the first fast recovery diode Q3, realizing energy recovery. This process reduces energy waste and improves the efficiency of the overall circuit.
[0077] Once the first power tube Q1 is turned on again and the second power tube Q2 is turned off, the circuit returns to the initial state, and the current flows from the positive pole of the power supply through the first power tube Q1, the first inductor L, R1, and the third energy storage capacitor C3 to the ground, completing a complete cycle. In this way, the Class D amplifier utilizes the low on-resistance and high switching speed of the GaN power tube and the low reverse recovery current and high efficiency of the SiC fast recovery diode to achieve efficient current transmission and effective energy recovery, while reducing switching losses and electromagnetic interference (EMI), optimizing the quality of the audio signal and the thermal management of the circuit. This design not only improves the performance of the audio amplifier, but also conforms to the trend of environmental protection and energy saving.
[0078] It should be noted that, in each state, the working states of the first energy storage capacitor C1 , the second energy storage capacitor C2 and the third energy storage capacitor C3 are also different.
[0079] For the energy storage capacitor in the first state, before the first power tube Q1 is turned on, the first energy storage capacitor C1 may have been partially or completely charged. When the first power tube Q1 is turned on, the first energy storage capacitor C1 acts as an auxiliary power source to release the previously stored energy and help provide additional current; then when the current passes through the third energy storage capacitor C3, the third energy storage capacitor C3 begins to store energy. At this time, the second energy storage capacitor C2 does not directly participate in the flow of current. For the energy storage capacitor in the second state, the first energy storage capacitor C1 does not directly participate in the flow of current; the second energy storage capacitor C2 and the second power supply end release energy, through the second fast recovery diode Q4, then to the first inductor L, and finally to the third energy storage capacitor C3, and the third energy storage capacitor C3 begins to store energy. For the energy storage capacitor in the third state, a reverse current is generated, and the third energy storage capacitor C3 releases energy, which flows into the second energy storage capacitor C2 through the second power tube Q2 together with the reverse current, and the second energy storage capacitor C2 begins to store energy. For the energy storage capacitor in the fourth state, reverse current continues to be generated, the third energy storage capacitor C3 releases energy, and flows back to the first energy storage capacitor C1 through the first fast recovery diode Q3, and the first energy storage capacitor C1 starts to store energy. In this way, the current in the class D power amplifier circuit 100 can be recycled for many times, reducing unnecessary losses.
[0080] The present invention further proposes a class D power amplifier, which includes a class D power amplifier circuit 100. The specific structure of the class D power amplifier circuit 100 refers to the above embodiment. Since the class D power amplifier adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described one by one here.
[0081] The present invention further proposes an audio device, which includes a class D power amplifier circuit 100 or a class D power amplifier. The specific structures of the class D power amplifier circuit 100 and the class D power amplifier refer to the above embodiments. Since the audio device adopts all the technical solutions of all the above embodiments, it has at least all the beneficial effects brought by the technical solutions of the above embodiments, which will not be described one by one here.
[0082] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.
Claims
1. A class D power amplifier circuit, characterized in that: The class D power amplifier circuit comprises: First inductor; an amplifier circuit, the amplifier circuit being connected to the first end of the first inductor, the amplifier circuit being alternately turned on and off within a preset frequency to generate a pulse current, the pulse current flowing to the first inductor; A leakage circuit, the leakage circuit being arranged in parallel with the amplifying circuit; the leakage circuit being used to discharge the current flowing through the amplifying circuit after the amplifying circuit is cut off; An energy storage circuit is electrically connected to the leakage circuit and the amplifier circuit, and is used to receive and store the electric energy output by the leakage circuit.
2. The class D power amplifier circuit according to claim 1, characterized in that: The energy storage circuit is also used to release the electric energy; when the amplifying circuit is in the on state, the energy storage circuit releases the electric energy so that the electric energy is at least a part of the pulse current and flows to the first inductor.
3. The class D power amplifier circuit according to claim 1, characterized in that: The amplifier circuit includes a first power tube and a second power tube, the source of the first power tube and the drain of the second power tube are connected to the first end of the first inductor; the drain of the first power tube is connected to the energy storage circuit, and the source of the second power tube is connected to the energy storage circuit.
4. The class D power amplifier circuit as claimed in claim 3, characterized in that: The leakage circuit comprises: a first fast recovery diode, arranged in parallel with the first power tube, wherein the cathode of the first fast recovery diode is connected to the drain of the first power tube, and the anode of the first fast recovery diode is connected to the source of the first power tube; A second fast recovery diode is arranged in parallel with the second power tube, an anode of the second fast recovery diode is connected to the drain of the second power tube, and a cathode of the first fast recovery diode is connected to the source of the second power tube.
5. The class D power amplifier circuit as claimed in claim 4, characterized in that: The first power tube and / or the second power tube is a gallium nitride power tube; And / or, the first fast recovery diode and / or the second fast recovery diode is a silicon carbide diode.
6. The class D power amplifier circuit as claimed in claim 3, characterized in that: The energy storage circuit comprises: A first energy storage capacitor, wherein a first end of the first energy storage capacitor is connected to a drain of the first power tube; A second energy storage capacitor, wherein a first end of the second energy storage capacitor is connected to a source of the second power tube; The second ends of the first energy storage capacitor and the second energy storage capacitor are grounded.
7. The class D power amplifier circuit according to claim 1, characterized in that: The class D power amplifier circuit also includes a first power supply terminal and a second power supply terminal, and the amplifier circuit includes a first power tube, a second power tube and a controller; The gates of the first power tube and the second power tube are connected to the controller; the source of the first power tube and the drain of the second power tube are connected to the first end of the first inductor; the drain of the first power tube is connected to the first power supply end, and the source of the second power tube is connected to the second power supply end.
8. The class D power amplifier circuit according to any one of claims 1 to 7, characterized in that: The class D power amplifier circuit further includes a third energy storage capacitor, one end of the third energy storage capacitor is connected to the second end of the first inductor, and the other end of the third energy storage capacitor is grounded; The third energy storage capacitor is used to receive and store at least a portion of the electric energy output from the second end of the first inductor.
9. A class D power amplifier, characterized in that: The class D power amplifier comprises the class D power amplifier circuit as described in any one of claims 1-8.
10. An audio device, characterized in that: The audio device comprises: The class D power amplifier circuit according to any one of claims 1 to 8; or The class D power amplifier as claimed in claim 9.