A current power amplifier

Abstract

The application relates to a current power amplifier, a driving signal providing module for processing and amplifying an input signal, outputting an upper arm driving signal and a lower arm driving signal; a current power amplification module for outputting a current power amplification signal under the action of the upper arm driving signal and the lower arm driving signal; a current sampling module for current sampling the current power amplification signal, outputting a current feedback signal and a current output signal; a current feedback module for amplifying the current feedback signal and feeding back the amplified current feedback signal to the driving signal providing module; and an output filtering module for filtering the current output signal and then outputting the same; thus, the current feedback signal is amplified by the current feedback module and then fed back to the driving signal providing module, so that the current power amplification module does not need to output a current power amplification signal with a high current value and a high power supply voltage, thereby significantly reducing the dissipation power.

Description

Technical Field

[0001] This invention relates to the field of integrated circuit technology, and more specifically to a current power amplifier. Background Technology

[0002] Current power amplifiers are used to increase the current power of input signals, such as... Figure 1 As shown, Figure 1 As an example of a current power amplifier, when power transistor Q1-1 is turned on and power transistor Q1-2 is turned off, the current loop in the current power amplifier is as follows: Figure 2 As shown in (a), the load resistance RL1 of the current power amplifier is often very small, or even short-circuited, so the power supply is mainly consumed through the power transistor Q2-1. Similarly, as Figure 2 As shown in (b), when the power transistor Q1-2 is turned on, the power supply is mainly consumed through the power transistor Q1-2.

[0003] Current power amplifiers generally require a certain load-driving capacity, meaning they must be able to guarantee the maximum current output when the load resistance RL is a constant value. Currently, to ensure this load-driving capacity, the power transistors in current power amplifiers typically require a high power supply voltage, and the power dissipation of these transistors is also high. This necessitates a large heat dissipation system to prevent the power transistors from being damaged by high temperatures, ultimately resulting in current power amplifiers being bulky and heavy.

[0004] In summary, to adapt to the trend of miniaturization and lightweight design, there is a certain demand for current power amplifiers with lower power supply voltage and lower maximum output current. Summary of the Invention

[0005] The main technical problem addressed by this invention is how to reduce the maximum power dissipation of a current power amplifier.

[0006] According to a first aspect, one embodiment provides a current power amplifier, comprising:

[0007] The drive signal providing module is used to condition and amplify the input signal to obtain the amplified signal, and divide the amplified signal into two drive signals. One drive signal is amplified to generate the upper arm drive signal, and the other drive signal is amplified to generate the lower arm drive signal.

[0008] The current power amplifier module is used to output a current power amplification signal under the action of the upper arm drive signal and the lower arm drive signal;

[0009] The current sampling module is used to sample the current power amplification signal to obtain a current sampling signal, and to divide the current sampling signal into a current feedback signal and a current output signal.

[0010] A current feedback module is used to amplify the current feedback signal and feed the amplified current feedback signal back to the drive signal providing module to adjust the upper arm drive signal and lower arm drive signal output by the drive signal providing module.

[0011] The output filtering module is used to filter the current output signal before outputting it.

[0012] The current power amplifier according to the above embodiment includes a drive signal providing module, a current power amplification module, a current sampling module, a current feedback module, and an output filtering module. The drive signal providing module conditions and amplifies the input signal, outputting an upper arm drive signal and a lower arm drive signal. The current power amplification module outputs a current power amplification signal under the action of the upper arm drive signal and the lower arm drive signal. The current sampling module samples the current power amplification signal, outputting a current feedback signal and a current output signal. The current feedback module amplifies the current feedback signal and feeds the amplified current feedback signal back to the drive signal providing module. The output filtering module filters the current output signal before outputting it. Therefore, by amplifying the current feedback signal through the current feedback module and then feeding it back to the drive signal providing module, the current power amplification module does not need to output a high-current-value current power amplification signal, nor does it require a high power supply voltage, thus significantly reducing the power dissipation of the power transistors in the current power amplification module.

[0013] In addition, the drive signal supply module and the current sampling module have the same reference ground, which means that the current sampling signal sampled by the current sampling module is only related to the sampling resistor being close to the output terminal. The feedback loop in the current feedback module can be approximated as voltage feedback, which significantly improves the output accuracy of the current power amplifier. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the structure of an existing current power amplifier;

[0015] Figure 2 This is a schematic diagram illustrating the working principle of an existing current power amplifier.

[0016] Figure 3 This is a schematic diagram of the structure of a current power amplifier according to one embodiment;

[0017] Figure 4 A circuit diagram of a drive signal providing module for one embodiment;

[0018] Figure 5 A partial circuit diagram of a current power amplifier according to one embodiment;

[0019] Figure 6 This is a circuit diagram of a current feedback module according to one embodiment;

[0020] Figure 7 This is a circuit diagram of an existing current feedback module;

[0021] Figure 8 This is a circuit diagram of a current feedback module according to another embodiment. Detailed Implementation

[0022] The present invention will now be described in further detail with reference to specific embodiments and accompanying drawings. Similar elements in different embodiments are referred to by associated similar element reference numerals. In the following embodiments, many details are described to facilitate a better understanding of this application. However, those skilled in the art will readily recognize that some features may be omitted in different situations, or may be replaced by other elements, materials, or methods. In some cases, certain operations related to this application are not shown or described in the specification. This is to avoid obscuring the core parts of this application with excessive description. For those skilled in the art, detailed description of these related operations is not necessary; they can fully understand the related operations based on the description in the specification and general technical knowledge in the art.

[0023] Furthermore, the features, operations, or characteristics described in the specification can be combined in any suitable manner to form various embodiments. At the same time, the steps or actions in the method description can be rearranged or adjusted in a manner obvious to those skilled in the art. Therefore, the various orders in the specification and drawings are only for the clear description of a particular embodiment and do not imply a necessary order, unless otherwise stated that a particular order must be followed.

[0024] The serial numbers assigned to components in this document, such as "first" and "second," are used only to distinguish the described objects and have no sequential or technical meaning. The terms "connection" and "linkage" used in this application, unless otherwise specified, include both direct and indirect connections (linkages).

[0025] Please refer to Figure 2In an example of a current power amplifier based on microprocessor-based relay protection, when the load resistance RL is 0.5 ohms and the maximum output AC current is 30A, the power consumption of the current power amplifier is mainly on the load resistance RL. However, to maintain the power supply voltage at no less than 21.2V, a margin of 1-2V is usually left according to the characteristics of the power transistor, i.e., the power supply voltage is no less than ±23V. But when the load resistance RL is 0 ohms, i.e., the output is short-circuited, all the power is applied to the power transistor, and its power dissipation is as high as 450VA. A huge heat dissipation system is required to ensure that the power amplifier is not damaged due to high temperature. Therefore, current power amplifiers based on microprocessor-based relay protection have the disadvantages of being large in size and heavy in weight.

[0026] To address the aforementioned issues, in this embodiment of the invention, firstly, the current feedback module does not directly feed the current feedback signal back to the drive signal providing module via a resistor. Instead, it amplifies the current feedback signal before feeding it back to the drive signal providing module. This makes the equivalent sampling resistor the product of the amplification factor of the current feedback signal and the actual sampling resistor. The output current of the current power amplifier is the ratio of the voltage to the current across the sampling resistor. Thus, increasing the value of the equivalent sampling resistor reduces the output current, thereby lowering the maximum power dissipation of the current power amplifier. Secondly, the drive signal providing module and the current sampling module share the same reference ground, ensuring that the current sampling signal sampled by the current sampling module is only related to the proximity of the sampling resistor to the output terminal. The feedback loop in the current feedback module can be approximated as voltage feedback, significantly improving the output accuracy of the current power amplifier.

[0027] Please refer to Figure 3 , Figure 3 This is a schematic diagram of the structure of a current power amplifier according to one embodiment. The current power amplifier includes: a drive signal providing module 101, a current power amplification module 102, a current sampling module 103, a current feedback module 104, and an output filtering module 105. The input terminal of the drive signal providing module 101 is used to receive an input signal. The input terminal of the current power amplification module 102 is connected to the output terminal of the drive signal providing module 101. The input terminal of the current sampling module 103 is connected to the output terminal of the current power amplification module 102. The output terminal of the current sampling module 103 is connected to the input terminal of the current feedback module 104 and the input terminal of the output filtering module 105.

[0028] The drive signal providing module 101 is used to condition and amplify the input signal to obtain an amplified signal, and then divides the amplified signal into two drive signals. One drive signal is amplified to generate an upper arm drive signal, and the other drive signal is amplified to generate a lower arm drive signal. In this embodiment, the input signal can be a small sinusoidal signal or other combined waveform small signals. Since the input signal is a small signal and contains some interference signals, it is necessary to condition and amplify the input signal first to suppress interference and ensure that the current value of the amplified signal has a fixed proportional relationship with the current value of the input signal. Furthermore, as those skilled in the art know, the circuit power amplification module 102 includes an upper arm power transistor and a lower arm power transistor, which require two drive signals to drive them separately. The drive signal providing module 101 provided in this embodiment divides the amplified signal into two drive signals. One drive signal generates an upper arm drive signal to provide the drive voltage and bias voltage for the upper arm power transistor, and the other drive signal generates a lower arm drive signal to provide the drive voltage and bias voltage for the lower arm power transistor.

[0029] The current power amplifier module 102 is used to output a current power amplification signal under the action of the upper arm drive signal and the lower arm drive signal. The current power amplifier module 102 includes an upper arm power transistor and a lower arm power transistor, which are driven to conduct or turn off by the upper arm drive signal and the lower arm drive signal, respectively. By alternately turning on the upper arm power transistor and the lower arm power transistor, a current power amplification signal with a constant current value is output.

[0030] The current sampling module 103 is used to sample the current power amplification signal to obtain a current sampling signal, which is then divided into a current feedback signal and a current output signal. After sampling the current power amplification signal output by the current power amplification module 102, the current sampling module 103 obtains a current sampling signal, which is divided into two paths: one as a current feedback signal and the other as a current output signal. In this embodiment, current sampling can be performed using a sampling resistor.

[0031] The current feedback module 104 is used to amplify the current feedback signal and feed the amplified current feedback signal back to the drive signal providing module 101 to adjust the upper arm drive signal and lower arm drive signal output by the drive signal providing module.

[0032] The output filtering module 105 is used to filter the current output signal before outputting it.

[0033] It should be noted that the drive signal providing module 101, the current sampling module 103 and the current feedback module 104 all have a first reference ground (GNDR); the current power amplification module 102 and the output filtering module 105 all have a second reference ground (GNDA).

[0034] The following is a detailed description of each of the above functional modules.

[0035] Please refer to Figure 4 The drive signal providing module 101 includes an input signal conditioning unit 1011 and a signal amplification and biasing unit 1012.

[0036] The input signal conditioning unit 1011 is used to perform differential amplification and inverting proportional amplification on the input signal to obtain a conditioned signal. The current amplitude of the conditioned signal has a preset proportional relationship with the current amplitude of the input signal.

[0037] The signal amplification and biasing unit 1012 is used to amplify the conditioned signal to obtain the amplified signal, and divide the amplified signal into two drive signals. One drive signal is amplified by a fixed voltage value to generate the upper arm drive signal, and the other drive signal is amplified by a fixed voltage value to generate the lower arm drive signal.

[0038] In one embodiment, the input signal conditioning unit 1011 includes a differential amplifier circuit and an inverting amplifier circuit.

[0039] The differential amplifier circuit includes an operational amplifier U1A, resistors R1, R2, R3, and R4. The non-inverting input of operational amplifier U1A receives the input signal CR_SIG through resistor R1. The non-inverting input of operational amplifier U1A is also connected to the first reference ground GNDR through resistor R3. The inverting input of operational amplifier U1A is connected to the second reference ground GNDA through resistor R2. The inverting input of operational amplifier U1A is also connected to the output of operational amplifier U1A through resistor R4. Operational amplifier U1A, resistors R1, R2, R3, and R4 constitute the structure of the differential amplifier circuit, which can differentially amplify the input signal CR_SIG, thereby amplifying the differential-mode signal of the input signal CR_SIG and canceling the common-mode signal. As can be seen from the structure of the differential amplifier circuit, the reference ground of operational amplifier U1A is the first reference ground GNDR, and the reference ground of operational amplifier U1A is the second reference ground GNDA. These are not the same ground. In this embodiment, the signal input reference ground (the second reference ground GNDA) can be used as the signal input terminal.

[0040] The inverting amplifier circuit includes: operational amplifier U1B, resistors R5, R6, and R7, and capacitor C1. The inverting input of operational amplifier U1B is connected to the output of differential amplifier U1A through resistor R5, and the inverting input of operational amplifier U1B is connected to its output through resistor R6. Capacitor C1 is connected in parallel across resistor R6. The non-inverting input of operational amplifier U1B is connected to the first reference ground GNDR through resistor R7. The output of operational amplifier U1B is used to output the conditioned signal. Operational amplifier U1B, along with resistors R5, R6, R7, and capacitor C1, constitutes an inverting amplifier. Furthermore, capacitor C1 can perform low-pass filtering on the signal input to operational amplifier U1B. Thus, by further inverting and amplifying the signal output from the differential amplifier circuit, the ratio between the conditioned signal output by operational amplifier U1B and the input signal can be adjusted, ensuring a fixed proportional relationship between the final output current signal and the input signal CR_SIG.

[0041] As can be foreseen by those skilled in the art, operational amplifier U1A and operational amplifier U1B can be two independent operational amplifier devices, or they can be two operational amplifier functional modules with the same function contained in the same package.

[0042] In one embodiment, the signal amplification and biasing unit 1012 includes: a signal amplification circuit, an upper arm biasing circuit, and a lower arm biasing circuit.

[0043] The signal amplification circuit includes: operational amplifier U2B, potentiometer VR1, resistors R8, R9, R10, and R15, capacitors C2 and C4. The inverting input of operational amplifier U2B receives the conditioned signal through resistor R8. The inverting input of operational amplifier U2B is also connected to its output through capacitor C4. The non-inverting input of operational amplifier U2B is connected to the sliding contact of potentiometer VR1 through resistor R9. One end of potentiometer VR1 is connected to the first voltage supply terminal REF_P6V, and the other end is connected to the second voltage supply terminal REF_N6V. The non-inverting input of operational amplifier U2B is also connected to the first reference ground GNDR through resistor R10. Capacitor C2 is connected in parallel across resistor R10. The output of operational amplifier U2B outputs the amplified signal through resistor R15. Potentiometer VR1 is used to adjust the zero bias of the final output current signal, and capacitor C4 filters out high-frequency interference signals. The signal output from the operational amplifier U2B is split into two paths by resistor R15, which are used to drive the upper arm bias circuit and the lower arm bias circuit respectively.

[0044] The upper arm bias circuit includes: operational amplifier U3A, resistors R16, R18, R20, and R21, capacitors C5 and C7. The inverting input of operational amplifier U3A receives the amplified signal through resistor R16. The inverting input of operational amplifier U3A is also connected to the output of operational amplifier U3A through resistor R18. Capacitor C5 is connected in parallel across resistor R18. The non-inverting input of operational amplifier U3A is connected to the first voltage supply terminal REF_P6V through resistor R20. The non-inverting input of operational amplifier U3A is also connected to the first reference ground GNDR through resistor R21. Capacitor C7 is connected in parallel across resistor R21. The output of operational amplifier U3A is used to output the upper arm drive signal. The upper arm bias circuit is the driving and biasing circuit for the upper arm power transistor in the current power amplifier module 102. The non-inverting input terminal of the operational amplifier U3A is connected to a voltage divider network consisting of resistors R20 and R21 and capacitor C7. The voltage divider network is powered by a +6V (REF_P6V) reference voltage. That is, the non-inverting input terminal of the operational amplifier U3A is a fixed reference voltage obtained by dividing REF_P6V, so that the amplitude of the upper arm driving signal is increased by a fixed value based on the driving signal, avoiding the switching voltage of the upper arm power transistor, so that the waveform of the circuit power amplification signal output by the current power amplifier module 102 is continuous.

[0045] The lower arm bias circuit includes: operational amplifier U3B, resistors R17, R19, R22, R23, capacitors C6 and C8. The inverting input of operational amplifier U3B receives the amplified signal through resistor R17. The inverting input of operational amplifier U3B is also connected to the output of operational amplifier U3B through resistor R19. Capacitor C6 is connected in parallel across resistor R19. The non-inverting input of operational amplifier U3B is connected to the first voltage supply terminal REF_P6V through resistor R22. The non-inverting input of operational amplifier U3B is also connected to the first reference ground GNDR through resistor R23. Capacitor C8 is connected in parallel across resistor R23. The output of operational amplifier U3B is used to output the lower arm drive signal. The lower arm bias circuit is the drive and bias circuit for the lower arm power transistor in the current power amplifier module 102. Its working principle is the same as that of the upper arm bias circuit, and will not be described again here.

[0046] Please refer to Figure 5 In one embodiment, the current power amplification module 102 includes an upper arm power amplification unit 1021 and a lower arm power amplification unit 1022.

[0047] The upper arm power amplifier unit 1021 is used to output an upper arm current power amplification signal under the action of the upper arm drive signal.

[0048] The lower arm power amplifier unit 1022 is used to output the lower arm current power amplification signal under the action of the lower arm drive signal.

[0049] The current power amplification signal includes the upper arm current power amplification signal and the lower arm current power amplification signal.

[0050] The upper arm power amplifier unit 1021 and the lower arm power amplifier unit 1022 include power transistors Q1 and Q2, and resistors R24, R25, R26, R27, R28, R29, R30, and R31. Power transistor Q1 is an N-channel MOSFET, and power transistor Q2 is a P-channel MOSFET. Resistors R24 and R25 are connected to the gates of power transistors Q1 and Q2, respectively, for current limiting. The drain of power transistor Q1 is connected to the positive power supply +6V_P of the power amplifier; the source of power transistor Q1 is connected to the source of power transistor Q2, and the drain of power transistor Q2 is connected to the negative power supply -6V_P of the power amplifier. It should be noted that the reference ground of the power amplifier power supply in this embodiment is the second reference ground GNDA. The connection between the sources of power transistors Q1 and Q2 serves as the output terminal of the current power amplifier module 102. Resistors R26, R27, and R30 form the bleeder resistor for power transistor Q1. Due to manufacturing process limitations, the junction capacitance of MOSFETs is often larger than that of transistors. Therefore, an additional bleeder resistor provides a discharge path for the junction capacitance, thereby improving the operating speed of the MOSFET. Similarly, resistors R28, R29, and R31 are the bleeder resistors for power transistor Q2.

[0051] The current sampling module 103 includes a sampling resistor RS; one end of the sampling resistor RS is used to acquire a current power amplification signal, and the other end of the sampling resistor RS is used to output a current feedback signal and a current output signal. Furthermore, in this embodiment, the end of the sampling resistor RS used to acquire the current power amplification signal is also connected to a first reference ground GNDR, and the end of the sampling resistor RS used to output the current feedback signal and the current output signal is connected to the current feedback module 104 and the output filtering module 105.

[0052] The sampling resistor RS used in this embodiment is a 4-wire high-precision shunt sampling resistor. The selected resistance value is 0.02 ohms. Those skilled in the art will foresee that the resistance value of the sampling resistor RS is not limited to 0.02 ohms.

[0053] Please refer to Figure 6 , Figure 6 The circuit structure diagram of the current feedback module 104 provided in an embodiment of the present invention is shown. The current feedback module 104 includes an operational amplifier unit. The operational amplifier unit is used to proportionally amplify the current feedback signal to obtain an amplified current feedback signal.

[0054] The operational amplifier unit includes: operational amplifier U2A, resistors R11, R12, R13, R14, and capacitor C3. The non-inverting input of operational amplifier U2A receives the current feedback signal CURR_SENS through resistor R12. The inverting input of operational amplifier U2A is connected to the first reference ground GNDR through resistor R11. The inverting input of operational amplifier U2A is connected to the output of operational amplifier U2A through resistor R13. Resistor C3 is connected in parallel across resistor R13. The output of operational amplifier U2A is connected to the inverting input of operational amplifier U2B through resistor R14. The output of operational amplifier U2A outputs the amplified current feedback signal CURR_A through resistor R14. In this embodiment, the current feedback signal shunted from the sampling resistor RS is connected to the non-inverting input of operational amplifier U2A via resistor R12. The inverting input of operational amplifier U2A is connected to the first reference ground GNDR via resistor R11. The first reference ground GNDR can be considered as one end of the sampling resistor RS connected to the first reference ground GNDR. The output of operational amplifier U2A is connected to the inverting input via a parallel resistor R13 and capacitor C3. The circuit of this operational amplifier unit can be regarded as an I / V conversion circuit for the current feedback signal.

[0055] In one embodiment, the output filtering module 105 includes an inductor L1, a resistor R32, and a capacitor C9. One end of the inductor L1 is connected to the output terminal of the sampling resistor RS, and the other end is connected to the output terminal of the current power amplifier. One end of the resistor R32 is connected to the second reference ground GNDA through the capacitor C9, and the other end of the resistor R32 is connected to the output terminal of the current power amplifier.

[0056] Please refer to Figure 7 , Figure 7 An example of a current feedback module is shown. It should be noted that, in order to better illustrate the working principle of existing current feedback modules, Figure 7 The circuit structure shown contains a current power amplifier, which is a simplified version of an existing current power amplifier circuit structure. It includes resistors R2-1, R2-2, R2-3, and R2-4, operational amplifier A2-1, power transistors Q2-1 and Q2-2, resistor RS2, and load resistor RL2. This embodiment analyzes the existing current feedback module and finds that, in this current feedback module, resistors R2-1 = R2-2 = R2-3 = R2-4. Then, the current IL on the load resistor RL2 is IL = VS / RS2, where VS is the voltage of the input signal. However, this type of differential balanced feedback requires resistors R2-1 to R2-4 to have high precision to ensure output accuracy. Therefore, the existing current feedback module is prone to output current changes when under load due to the imbalance of resistors R2-1 to R2-4.

[0057] Please refer to Figure 8 , Figure 8 A schematic diagram of the current feedback module 104 in this embodiment is shown. It should be noted that... Figure 8 The circuit structure of the current power amplifier shown is a simplified circuit structure of the current power amplifier provided in the embodiment of the present invention. It includes: resistors R3-1, R3-2, R3-3, R3-4, R3-5, R3-6, and R3-7; a sampling resistor RS3; a load resistor RL3; operational amplifiers A3-1 and A3-2; ​​and a potentiometer VR3. Since the first reference ground GNDR connected to resistor R3-3 and the first reference ground GNDR connected to sampling resistor RS3 are the same reference ground, that is, one end of resistor R3-3 connected to the first reference ground GNDR can be equivalent to the end of sampling resistor RS3 connected to the first reference ground GNDR (dashed line connection). Those skilled in the art will understand that… Figure 8 The current feedback module 104 shown is somewhat similar in circuit structure to existing current feedback modules, but there are still two differences and the resulting technical effects.

[0058] First, one end of the current feedback signal output from the sampling resistor RS3 is not directly connected to the non-inverting input of the driving operational amplifier A3-2 via resistor R3-2. Instead, it is amplified by operational amplifier A3-2 and then connected to the non-inverting input of the driving operational amplifier A3-1 via resistor R3-2. Therefore, the sampled current signal is amplified and fed back to the driving end. The equivalent sampling resistor becomes the product of the amplification factor of A3-2 and RS3, and is no longer RS3.

[0059] Second, the first reference ground GNDR of operational amplifier A3-1 is different from the second reference ground GNDA; it is a separately powered floating ground GNDR. Therefore, the current signal output is only related to the end of the sampling resistor RS3 closest to its output signal, and the current feedback module 104 can be approximated as voltage feedback, thus greatly improving accuracy.

[0060] It should be noted that the power supply voltage of the current power amplifier module 102 in this embodiment of the invention is not limited to ±6V. Depending on the adjustment of the device parameters in the circuit, the power supply voltage can be varied.

[0061] The above examples illustrate the present invention only to aid in understanding it and are not intended to limit the scope of the invention. Those skilled in the art can make various simple deductions, modifications, or substitutions based on the principles of this invention.

Claims

1. A current power amplifier, characterized in that, include: The drive signal providing module is used to condition and amplify the input signal to obtain the amplified signal, and divide the amplified signal into two drive signals. One drive signal is amplified to generate the upper arm drive signal, and the other drive signal is amplified to generate the lower arm drive signal. The current power amplifier module is used to output a current power amplification signal under the action of the upper arm drive signal and the lower arm drive signal; The current sampling module is used to sample the current power amplification signal to obtain a current sampling signal, and to divide the current sampling signal into a current feedback signal and a current output signal. A current feedback module is used to amplify the current feedback signal and feed the amplified current feedback signal back to the drive signal providing module to adjust the upper arm drive signal and lower arm drive signal output by the drive signal providing module. An output filtering module is used to filter the current output signal before outputting it. The current sampling module includes: a sampling resistor RS; One end of the sampling resistor RS is used to acquire the current power amplification signal, and the other end of the sampling resistor RS is used to output a current feedback signal and a current output signal; the end of the sampling resistor RS used to acquire the current power amplification signal is also connected to a first reference ground. The drive signal providing module includes: An input signal conditioning unit is used to perform differential amplification and inverting proportional amplification on the input signal to obtain a conditioned signal, wherein the current amplitude of the conditioned signal has a preset proportional relationship with the current amplitude of the input signal. The signal amplification and bias unit is used to amplify the conditioned signal to obtain an amplified signal, and divide the amplified signal into two driving signals. One driving signal is amplified by a fixed voltage value to generate an upper arm driving signal, and the other driving signal is amplified by a fixed voltage value to generate a lower arm driving signal. The current feedback signal is amplified and fed back to the drive signal providing module, so that the equivalent sampling resistor is the product of the amplification factor of the current feedback signal and the sampling resistor; thus, increasing the resistance value of the equivalent sampling resistor reduces the output current value, thereby reducing the maximum power dissipation of the current power amplifier.

2. The current power amplifier as described in claim 1, characterized in that, The drive signal providing module, the current sampling module, and the current feedback module all have a first reference ground; Both the current power amplifier module and the output filter module have a second reference ground.

3. The current power amplifier as described in claim 1, characterized in that, The current power amplifier module includes: The upper arm power amplifier unit is used to output an upper arm current power amplification signal under the action of the upper arm drive signal; The lower arm power amplifier unit is used to output a lower arm current power amplification signal under the action of the lower arm drive signal; The current power amplification signal includes the upper arm current power amplification signal and the lower arm current power amplification signal.

4. The current power amplifier as described in claim 1, characterized in that, The current feedback module includes: The operational amplifier unit is used to proportionally amplify the current feedback signal to obtain an amplified current feedback signal.

5. The current power amplifier as described in claim 1, characterized in that, The input signal conditioning unit includes: a differential amplifier circuit and an inverting amplifier circuit; The differential amplifier circuit includes: operational amplifier U1A, resistors R1, R2, R3, and R4. The non-inverting input terminal of operational amplifier U1A receives the input signal through resistor R1. The non-inverting input terminal of operational amplifier U1A is also connected to a first reference ground through resistor R3. The inverting input terminal of operational amplifier U1A is connected to a second reference ground through resistor R2. The inverting input terminal of operational amplifier U1A is also connected to the output terminal of operational amplifier U1A through resistor R4. The inverting amplifier circuit includes: operational amplifier U1B, resistors R5, R6, and R7, and capacitor C1. The inverting input terminal of operational amplifier U1B is connected to the output terminal of differential amplifier U1A through resistor R5. The inverting input terminal of operational amplifier U1B is connected to the output terminal of operational amplifier U1B through resistor R6. Capacitor C1 is connected in parallel across resistor R6. The non-inverting input terminal of operational amplifier U1B is connected to a first reference ground through resistor R7. The output terminal of operational amplifier U1B is used to output the conditioned signal.

6. The current power amplifier as described in claim 1, characterized in that, The signal amplification and biasing unit includes: Signal amplification circuit, upper arm bias circuit, and lower arm bias circuit; The signal amplification circuit includes: operational amplifier U2B, potentiometer VR1, resistors R8, R9, R10, and R15, capacitors C2 and C4. The inverting input of operational amplifier U2B receives the conditioned signal through resistor R8. The inverting input of operational amplifier U2B is also connected to the output of operational amplifier U2B through capacitor C4. The non-inverting input of operational amplifier U2B is connected to the sliding contact of potentiometer VR1 through resistor R9. One end of potentiometer VR1 is connected to a first voltage supply terminal, and the other end of potentiometer VR1 is connected to a second voltage supply terminal. The non-inverting input of operational amplifier U2B is also connected to a first reference ground through resistor R10. Capacitor C2 is connected in parallel across resistor R10. The output of operational amplifier U2B outputs the amplified signal through resistor R15. The upper arm bias circuit includes: operational amplifier U3A, resistors R16, R18, R20, and R21, capacitors C5 and C7. The inverting input of operational amplifier U3A receives the amplified signal through resistor R16. The inverting input of operational amplifier U3A is also connected to the output of operational amplifier U3A through resistor R18. Capacitor C5 is connected in parallel across resistor R18. The non-inverting input of operational amplifier U3A is connected to the first voltage supply terminal through resistor R20. The non-inverting input of operational amplifier U3A is also connected to the first reference ground through resistor R21. Capacitor C7 is connected in parallel across resistor R21. The output of operational amplifier U3A is used to output the upper arm drive signal. The lower arm bias circuit includes: operational amplifier U3B, resistors R17, R19, R22, R23, capacitors C6 and C8. The inverting input of operational amplifier U3B receives the amplified signal through resistor R17. The inverting input of operational amplifier U3B is also connected to the output of operational amplifier U3B through resistor R19. Capacitor C6 is connected in parallel across resistor R19. The non-inverting input of operational amplifier U3B is connected to the first voltage supply terminal through resistor R22. The non-inverting input of operational amplifier U3B is also connected to the first reference ground through resistor R23. Capacitor C8 is connected in parallel across resistor R23. The output of operational amplifier U3B is used to output the lower arm drive signal.

7. The current power amplifier as described in claim 6, characterized in that, The operational amplifier unit includes: operational amplifier U2A, resistors R11, R12, and R13, and capacitor C3. The non-inverting input of operational amplifier U2A receives the current feedback signal through resistor R12, the inverting input of operational amplifier U2A is connected to the first reference ground through resistor R11, the inverting input of operational amplifier U2A is connected to the output of operational amplifier U2A through resistor R13, and resistor C3 is connected in parallel across resistor R13. The output of operational amplifier U2A is connected to the inverting input of operational amplifier U2B through feedback resistor R14.

8. The current power amplifier as described in claim 1, characterized in that, The sampling resistor RS is a 4-line high-precision shunt sampling resistor.

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