A power amplification circuit, a power amplifier and a chip

Abstract

The application discloses a power amplification circuit, a power amplifier and a chip. The circuit comprises a load, a driving module, a low-voltage domain current output module, a high-voltage domain current output module and a current adjusting module. The driving module is used for simultaneously outputting a first driving signal and a second driving signal. When the voltage of the load does not reach a target voltage, the low-voltage domain current output module outputs a first current, and the first current is increased with the increase of the voltage of the load; when the voltage of the load reaches the target voltage, the high-voltage domain current output module outputs a second current, and the size of the second current is gradually increased with the further increase of the voltage of the load, and meanwhile, the current adjusting module gradually reduces the size of the first current. Compared with the scheme of taking power from a low-voltage domain power tube alone, the application can provide a larger output swing; compared with the scheme of taking power from a high-voltage domain power tube alone, the power consumption of the overall circuit is reduced. Therefore, the application has the characteristics of low power consumption and high output swing.

Description

Technical Field

[0001] This invention relates to the field of audio signal processing technology, specifically to a power amplifier circuit, a power amplifier, and a chip. Background Technology

[0002] In the field of audio applications, in order to reduce power consumption, the existing technical solution is to operate the output power transistor of the power amplifier in the low voltage domain. On the one hand, the power consumption of the overall circuit can be effectively reduced by the buck driving method. On the other hand, the power transistor is a low voltage transistor. Since the low voltage transistor is generally small in area, a large driving capability can be achieved in a small area.

[0003] However, low-voltage power amplifiers also limit the maximum swing they can output, thus limiting the maximum volume they can output. Summary of the Invention

[0004] One objective of this invention is to provide a power amplifier circuit, power amplifier, and chip that addresses the problem that existing power amplifiers cannot simultaneously achieve low power consumption and high output swing.

[0005] In a first aspect, embodiments of the present invention provide a power amplifier circuit, comprising:

[0006] The drive module is used to output a synchronized first drive signal and a second drive signal;

[0007] A current regulation module is used to receive a first current and output the first current to the load, and when the voltage of the load reaches the target voltage, the magnitude of the first current is gradually reduced as the voltage of the load increases;

[0008] A low-voltage current output module, electrically connected to the drive module and the current regulation module, is used to receive a low-voltage supply voltage, output the first current according to the first drive signal, and gradually increase the first current as the load voltage increases when the load voltage does not reach the target voltage; and

[0009] The high-voltage current output module is electrically connected to the drive module and is used to connect to the high-voltage power supply voltage. When the voltage of the load reaches the target voltage, it outputs a second current to the load according to the second drive signal, and the magnitude of the second current gradually increases as the voltage of the load increases.

[0010] Optionally, the driving module includes:

[0011] Signal generation unit, used to generate reference voltage signal;

[0012] The first conversion unit is electrically connected to both the signal generation unit and the low-voltage domain current output module, and is used to acquire the reference voltage signal, convert the reference voltage signal into a first driving signal, and output the first driving voltage signal to the low-voltage domain current output module; and

[0013] The second conversion unit is electrically connected to the signal generation unit and the high-voltage domain current output module, respectively, and is used to acquire the reference voltage signal, convert the reference voltage signal into a second driving signal, and output the second driving voltage signal to the high-voltage domain current output module.

[0014] The voltage of the second driving signal is greater than the voltage of the first driving signal.

[0015] Optionally, the current regulation module includes:

[0016] A current regulation drive unit is used to output a third drive signal; and

[0017] The first current regulation unit is electrically connected to the low-voltage domain current output module, the current regulation drive unit and the load, respectively. It is used to output the first current to the load according to the third drive signal, and gradually reduce the magnitude of the first current as the voltage of the load increases when the voltage of the load reaches the target voltage.

[0018] Optionally, the current regulation drive unit includes:

[0019] A first current source, the positive terminal of which is connected to the supply voltage, and the negative terminal of which is connected to the current regulating unit; and

[0020] The first resistor has one end connected to the negative terminal of the first current source and the other end grounded.

[0021] Optionally, the first current regulating unit includes:

[0022] A first transistor, the drain of which is connected to the low-voltage current output module, the source of which is connected to one end of the load, and the gate of which is connected to the current regulation drive unit; and

[0023] The second transistor has its source connected to the low-voltage current output module, its drain connected to the other end of the load, and its gate connected to the current regulation drive unit.

[0024] Optionally, the current regulation module is further configured to disconnect the first current output to the load when the voltage of the load exceeds the reference voltage.

[0025] Optionally, the current regulation module includes:

[0026] A reference voltage generation unit is used to generate the reference voltage;

[0027] A comparison unit, electrically connected to both the reference voltage generation unit and the load, is used to compare the reference voltage with the load voltage, and output a fourth drive signal when the load voltage is less than the reference voltage, and output a fifth drive signal when the load voltage reaches or exceeds the reference voltage; and

[0028] The second current regulation unit is electrically connected to the low-voltage current output module, the comparison unit, and the load, respectively. It is used to output the first current to the load according to the fourth drive signal, reduce the magnitude of the first current as the voltage of the load increases, and disconnect the first current output to the load according to the fifth drive signal.

[0029] Optionally, the reference voltage generation unit includes:

[0030] A second current source, the positive terminal of which is connected to the supply voltage, and the negative terminal of which is connected to the comparison unit; and

[0031] The second resistor has one end connected to the negative terminal of the second current source and the other end grounded.

[0032] Optionally, the comparison unit includes:

[0033] A first comparator, wherein the negative input terminal of the first comparator is connected to one end of the load, the non-inverting input terminal of the first comparator is connected to the reference voltage generation unit, and the output terminal of the first comparator is connected to the second current regulation unit; and

[0034] The second comparator has its negative input connected to the other end of the load, its positive input connected to the reference voltage generation unit, and its output connected to the second current regulation unit.

[0035] Optionally, the second current regulating unit includes:

[0036] A third transistor, the drain of which is connected to the low-voltage current output module, the source of which is connected to one end of the load, and the gate of which is connected to the comparator unit; and

[0037] The fourth transistor has its source connected to the low-voltage current output module, its drain connected to the other end of the load, and its gate connected to the comparator unit.

[0038] In a second aspect, embodiments of this application provide a power amplifier, including the power amplifier circuit as described in any of the preceding claims.

[0039] In a second aspect, embodiments of this application provide a chip including the power amplifier circuit as described in any of the preceding claims.

[0040] Compared with existing technologies, the power amplifier circuit of the present invention includes a low-voltage domain current output module and a high-voltage domain current output module, which respectively supply current to the load to output an amplified audio signal through the load. The low-voltage domain current output module operates in the low-voltage domain, and the high-voltage domain current output module operates in the high-voltage domain, outputting a first current and a second current respectively based on the first and second drive signals output by the drive module. When the load voltage has not reached the target voltage, the low-voltage domain current output module gradually increases the magnitude of the first current as the load voltage increases; when the load voltage reaches the target voltage, the high-voltage domain current output module outputs the second current, and as the load voltage further increases, the magnitude of the second current slowly increases, while the current regulation module gradually decreases the magnitude of the first current.

[0041] As can be seen, compared to solutions that draw power solely from the low-voltage domain power transistor, this invention provides a larger output swing. With the increased swing, the current supply to the low-voltage domain power transistor is reduced, allowing the load to draw power from the high-voltage domain power transistor, thereby saving current. Compared to solutions that draw power solely from the high-voltage domain power transistor, this invention's high-voltage domain current output module outputs a second current after the load voltage reaches the target voltage, and this second current increases slowly as the load voltage further increases, which helps save circuit power consumption. Therefore, the power amplifier circuit of this invention features both low power consumption and a high output swing. Attached Figure Description

[0042] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0043] Figure 1 This is a schematic diagram of a power amplifier circuit in the prior art;

[0044] Figure 2 This is a first principle block diagram of the power amplifier circuit according to an embodiment of the present invention;

[0045] Figure 3This is a first schematic diagram of the power amplifier circuit according to an embodiment of the present invention;

[0046] Figure 4 This is a second principle block diagram of the power amplifier circuit according to an embodiment of the present invention;

[0047] Figure 5 This is a third principle block diagram of the power amplifier circuit according to an embodiment of the present invention;

[0048] Figure 6 This is a schematic diagram of the current regulation drive unit according to an embodiment of the present invention;

[0049] Figure 7 This is a fourth principle block diagram of the power amplifier circuit according to an embodiment of the present invention;

[0050] Figure 8 This is a schematic diagram of the comparison unit and the reference voltage generation unit according to an embodiment of the present invention;

[0051] Figure 9 This is a second schematic diagram of the power amplifier circuit according to an embodiment of the present invention;

[0052] Figure 10 This is a schematic diagram of the driving module according to an embodiment of the present invention. Detailed Implementation

[0053] To facilitate understanding of this disclosure, a more detailed description is provided below with reference to the accompanying drawings and specific embodiments. It should be noted that when an element is described as being "fixed to" another element, it can be directly on the other element, or one or more intermediate elements may exist between them. When an element is described as being "electrically connected" to another element, it can be directly connected to the other element, or one or more intermediate elements may exist between them. The terms "upper," "lower," "inner," "outer," "bottom," etc., used in this specification indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this disclosure. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0054] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. The terminology used in this disclosure is for the purpose of describing particular embodiments only and is not intended to limit the disclosure. The term "and / or" as used in this specification includes any and all combinations of one or more of the associated listed items. Furthermore, the technical features involved in the different embodiments of this disclosure described below may be combined with each other as long as they do not conflict with each other.

[0055] To better illustrate the technical solution of this embodiment, please refer to... Figure 1 , Figure 1 This is a current-technology power amplifier circuit in which power transistors M0, M1, M7, and M8 are all located in the low-voltage domain and output current to the load. This existing power amplifier circuit is limited in its output swing, preventing it from outputting a larger volume. Furthermore, to achieve the same signal-to-noise ratio, the noise floor requirement becomes higher. Other methods of voltage expansion through current starvation require a larger voltage domain; however, this method, in the positive feedback loop, causes a portion of the output signal to be amplified and fed back to the input, resulting in uncontrollable oscillations and leading to positive feedback lock-up, rendering the circuit malfunction. It also increases the area and power consumption costs of the circuit structure. Additionally, voltage expansion using the current starvation method requires a heavy load to achieve, which places demands on the load.

[0056] This embodiment provides a power amplifier circuit for amplifying audio signals. By amplifying low-level audio signals to a suitable power level, a larger volume is output through a load (such as a speaker, loudspeaker, etc.).

[0057] Please refer to Figure 2The power amplifier circuit 100 of this embodiment includes a drive module 50, a low-voltage current output module 10, a high-voltage current output module 20, and a current regulation module 30. The drive module outputs a synchronized first drive signal and a second drive signal. The current regulation module receives a first current and outputs it to the load. When the load voltage reaches the target voltage, the magnitude of the first current gradually decreases as the load voltage increases. The low-voltage current output module is electrically connected to the drive module and the current regulation module. It receives a low-voltage supply voltage, outputs the first current according to the first drive signal, and gradually increases the first current as the load voltage increases when the load voltage does not reach the target voltage. The high-voltage current output module is electrically connected to the drive module. It receives a high-voltage supply voltage, outputs a second current to the load according to the second drive signal when the load voltage reaches the target voltage, and gradually increases the magnitude of the second current as the load voltage increases.

[0058] The working principle of the power amplifier circuit 100 in this embodiment is as follows:

[0059] When no volume is output, the low-voltage current output module 10 and the high-voltage current output module 20 do not output current to the load 40.

[0060] When the output amplitude is small, due to the small load voltage, the voltage flowing through the load is mainly provided by the first current from the low-voltage domain current output module. The high-voltage domain current output module does not provide a second current, or the output second current is extremely small compared to the first current. The load 40 outputs volume after receiving the first current.

[0061] As the output amplitude gradually increases, i.e. the voltage of the load 40 gradually increases, when the target voltage is reached, the high voltage domain current output module outputs a second current, and the current regulation module 30, which is located between the low voltage domain current output module 10 and the load 40, reduces the output of the first current so that the operating current of the load 40 is provided more by the high voltage domain current output module 20.

[0062] Optionally, the current regulation module 30 may regulate the first current in response to voltage changes in the load 40 in a linear or non-linear manner, and in some embodiments, it may also be regulated according to a preset rule.

[0063] It is understandable that the power amplifier circuit 100 in this embodiment uses a low-voltage domain current output module 10 and a high-voltage domain current output module 20. It is not simply a matter of selecting a power transistor in one voltage domain to output current to the load 40 during a certain power supply period of the load 40. When the output amplitude is small, the required power supply current of the load 40 is basically provided by the low-voltage domain current output module 10. As the voltage of the load 40 gradually rises and reaches the target voltage, the current regulation module 30 gradually reduces the output of the first current, and the operating current of the load 40 is gradually provided by the high-voltage domain current output module 20. The current output transition during the power supply process is smooth, and a higher output swing is obtained.

[0064] The power amplifier circuit 100 of this embodiment offers several advantages. First, compared to a scheme that draws power solely from the low-voltage power transistor, it provides a larger output swing. Second, compared to a scheme that draws power solely from the high-voltage power transistor, the high-voltage current output module outputs a second current after the load voltage reaches the target voltage, and this second current increases slowly as the load voltage further increases. This helps save circuit power consumption and reduces the area of ​​the power transistor. Therefore, the power amplifier circuit 100 of this embodiment combines low power consumption with a high output swing.

[0065] It should be noted that the "low voltage" and "high voltage" described in this embodiment are two voltages in relative terms, and are not descriptions of a specific voltage value or voltage range.

[0066] In some embodiments, please refer to Figure 3 The low-voltage current output module 10 includes a first power transistor PM0, a first grounding transistor NM1, a second power transistor PM1, and a second grounding transistor NM2. The gate of the first power transistor PM0 is connected to the driving module 50, the source of the first power transistor PM0 is used to connect to the low-voltage supply voltage, and the drain of the first power transistor PM0 is connected to the current regulation module 30, and is connected to one end VOUTP of the load 40 through the current regulation module 30.

[0067] The gate of the first grounding tube NM1 is connected to the driving module 50, the drain of the first grounding tube NM1 is connected to the drain of the first power tube PM0, and the source of the first grounding tube NM1 is grounded.

[0068] The gate of the second power transistor PM1 is connected to the drive module 50. The source of the first power transistor PM0 is used to connect to the low-voltage power supply voltage. The drain of the second power transistor PM1 is connected to the current regulation module 30 and connected to the other end VOUTN of the load 40 through the current regulation module 30.

[0069] The gate of the second grounding tube NM2 is connected to the driving module 50, the drain of the second grounding tube NM2 is connected to the drain of the second power tube PM1, and the source of the second grounding tube NM2 is grounded.

[0070] The high-voltage current output module 20 includes a third power transistor PM2 and a fourth power transistor PM3. The gate of the third power transistor PM2 is connected to the drive module 50, the source of the third power transistor PM2 is connected to the high-voltage supply voltage, and the drain of the third power transistor PM2 is connected to one end VOUTP of the load 40.

[0071] The gate of the fourth power transistor PM3 is connected to the drive module 50, the source of the fourth power transistor PM3 is used to connect to the high voltage supply voltage, and the drain of the fourth power transistor PM3 is connected to the other end VOUTN of the load 40.

[0072] It is understood that in this embodiment, the first drive signal (Pg1, Pg2) and the second drive signal (pgh1, pgh2) are both differential input signals. Each power transistor module is provided with an output power transistor corresponding to each end of the load 40. The first power transistor PM0 and the second power transistor PM1 are connected to the low-voltage supply voltage VDDPA and the first drive signal (Pg1, Pg2), and operate in the low-voltage domain, outputting a first current according to the first drive signal. The third power transistor PM2 and the fourth power transistor PM3 are connected to the high-voltage supply voltage AVDD and the second drive signal (pgh1, pgh2), and operate in the high-voltage domain, outputting a second current according to the second drive signal. The first grounding transistor NM1 and the second grounding transistor NM2 are switching devices set at the grounding terminal, and their drive signals can also be provided by the drive module 50 respectively.

[0073] In this embodiment, the first power transistor PM0 and the second power transistor PM1 are both P-channel low-voltage power transistors, the third power transistor PM2 and the fourth power transistor PM3 are both P-channel high-voltage power transistors, and the first grounding transistor NM1 and the second grounding transistor NM2 are both N-channel low-voltage power transistors.

[0074] In some embodiments, please refer to Figure 4 The driving module includes a signal generation unit 510, a first conversion unit 520, and a second conversion unit 530. The signal generation unit 510 generates a reference voltage signal. The first conversion unit 520 is electrically connected to both the signal generation unit 510 and the low-voltage domain current output module, and is used to acquire the reference voltage signal, convert it into a first driving signal, and output the first driving voltage signal to the low-voltage domain current output module. The second conversion unit 530 is electrically connected to both the signal generation unit 510 and the high-voltage domain current output module, and is used to acquire the reference voltage signal, convert it into a second driving signal, and output the second driving voltage signal to the high-voltage domain current output module.

[0075] Specifically, the drive module uses DC-DC level conversion to obtain a first drive signal and a second drive signal from the reference voltage signal, thereby synchronizing the first and second drive signals. The first conversion unit 520 is connected to the gate of the first power transistor PM0 and the gate of the second power transistor PM1, respectively. The second conversion unit 530 is connected to the gate of the third power transistor PM2 and the gate of the fourth power transistor PM3, respectively. The voltage of the second drive signal is greater than the voltage of the first drive signal.

[0076] When no volume is output, the static bias current of the third power transistor PM2 and the fourth power transistor PM3, which operate in the high voltage domain, is much smaller than the static bias current of the first power transistor PM0 and the second power transistor PM1, which operate in the low voltage domain. This results in the transconductance of the third power transistor PM2 and the fourth power transistor PM3 being much smaller than the transconductance of the first power transistor PM0.

[0077] When the output amplitude is small, the current regulation module 30 does not regulate the first current output by the low-voltage domain current output module 10. At this time, since the voltage changes of the first drive signal and the second drive signal are equal, and the transconductance of the third power transistor PM2 and the fourth power transistor PM3 is much smaller than that of the first power transistor PM0 and the second power transistor PM1, the operating current of the load 40 is mainly provided by the first current output by the first power transistor PM0 and the second power transistor PM1, while the second current obtained from the third power transistor PM2 and the fourth power transistor PM3 is relatively small.

[0078] As the output amplitude increases and the target voltage is reached, the current regulation module 30 reduces the output of the first current. The operating current of the load 40 is mainly provided by the second current output by the third power transistor PM2 and the fourth power transistor PM3, thereby widening the output swing and saving the first current of the low-voltage domain current output module 10.

[0079] Understandably, in this embodiment, the power amplifier circuit 100 draws more power from the low-voltage current output module 10 in the low-voltage domain when the output amplitude is small, which can meet the lower power consumption requirements. As the output amplitude gradually increases, the supply of the first current is reduced, and the operating current of the load 40 is mainly provided by the high-voltage current output module 20, thereby achieving higher power output.

[0080] In one embodiment, please refer to Figure 5A circuit structure for a current regulation module 30 is provided. The current regulation module 30 includes a current regulation drive unit 320 and a first current regulation unit 310. The current regulation drive unit 320 is used to output a third drive signal. The first current regulation unit 310 is electrically connected to a low-voltage current output module 10, the current regulation drive unit 320, and a load 40, respectively. It is used to output a first current to the load 40 according to the third drive signal, and to decrease the magnitude of the first current as the voltage of the load 40 increases.

[0081] Understandably, in the current regulation module 30 of this embodiment, the current regulation drive unit 320 generates a third drive signal to drive the first current regulation unit 310. The first current regulation unit 310 is located between the low-voltage domain current output module 10 and the load 40. It starts working according to the third drive signal and outputs a first current to the load 40. Furthermore, as the voltage of the load 40 gradually increases, the first current regulation unit 310 gradually reduces the output of the first current, so that the operating current of the load 40 is mainly provided by the high-voltage domain current output module 20.

[0082] Optional, please refer to Figure 6 The current regulation drive unit 320 includes a first current source I1 and a first resistor R1. The positive terminal of the first current source I1 is connected to the power supply voltage, and the negative terminal of the first current source I1 is connected to the current regulation unit. One end of the first resistor R1 is connected to the negative terminal of the first current source I1, and the other end of the first resistor R1 is grounded.

[0083] Understandably, this embodiment uses a current source and a resistor to form a bias circuit, and outputs a bias voltage as the third drive signal Vcas1 based on the supply voltage. The first resistor R1 can be an adjustable resistor to provide the voltage regulation function of the third drive signal Vcas1.

[0084] Optional, please refer to Figure 3The first current regulation unit 310 includes a first transistor Ms1 and a second transistor Ms2. The drain of the first transistor Ms1 is connected to the low-voltage domain current output module 10, the source of the first transistor Ms1 is connected to one end VOUTP of the load 40, and the gate of the first transistor Ms1 is connected to the current regulation drive unit 320. The gate of the first transistor Ms1 is connected to the negative terminal of the first current source I1 and one end of the first resistor R1, and the drain of the first transistor Ms1 is connected to the drain of the first power transistor PM0 and the drain of the first grounding transistor NM1. The source of the second transistor Ms2 is connected to the low-voltage domain current output module 10, the drain of the second transistor Ms2 is connected to the other end VOUTN of the load 40, and the gate of the second transistor Ms2 is connected to the current regulation drive unit 320. The gate of the second transistor Ms2 is connected to the negative terminal of the first current source I1 and one end of the first resistor R1, and the source of the second transistor Ms2 is connected to the drain of the second power transistor PM1 and the drain of the second grounding transistor NM2.

[0085] Understandably, both the first transistor Ms1 and the second transistor Ms2 are turned on according to the third drive signal Vcas1, so that the first current output by the low-voltage domain current output module 10 is output to the load 40. When there is no volume output in the static state, the first transistor Ms1 and the second transistor Ms2 have no current output. When the output amplitude is small, the first transistor Ms1 and the second transistor Ms2 are turned on and in the linear region, and the first current flows through the first transistor Ms1 and the second transistor Ms2 before being output to the load 40. As the voltage of the load 40 increases, the impedance of the first transistor Ms1 and the second transistor Ms2 gradually increases, and the current flowing through the first transistor Ms1 and the second transistor Ms2 gradually decreases. The first transistor Ms1 and the second transistor Ms2 gradually enter the saturation region until they are turned off, so that the operating current of the load 40 is mainly provided by the third power transistor PM2 and the fourth power transistor PM3. In addition, the first transistor Ms1 and the second transistor Ms2 in this embodiment can automatically cut off the low-voltage domain path under large output, thereby preventing overvoltage of the first grounding transistor NM1 and the second grounding transistor NM2.

[0086] In this embodiment, both the first transistor Ms1 and the second transistor Ms2 are N-channel field-effect transistors.

[0087] In another embodiment, please refer to Figure 7 Alternatively, another circuit structure for a current regulation module 30 is provided, which is also used to disconnect the first current output to the load 40 when the voltage of the load 40 exceeds the reference voltage.

[0088] Understandably, compared to the circuit structure of the aforementioned current regulation module 30, the current regulation module 30 of this embodiment directly disconnects the first current output by the low-voltage domain current output module 10 when the load 40 voltage reaches or exceeds the reference voltage. This allows the operating current of the load 40 to be entirely provided by the high-voltage domain current module, thereby achieving voltage expansion of the load 40 and saving the first current of the low-voltage domain current output module 10. Furthermore, the current regulation module 30 of this embodiment, by isolating the low-voltage path between the low-voltage domain current output module 10 and the load 40 when the load 40 voltage reaches or exceeds the reference voltage, also helps to avoid overvoltage of the low-voltage power transistor in the low-voltage domain current output module 10.

[0089] Optionally, the current regulation module 30 in this embodiment includes a reference voltage generation unit 350, a comparison unit 340, and a second current regulation unit 330. The reference voltage generation unit 350 generates a reference voltage. The comparison unit 340 is electrically connected to the reference voltage generation unit 350 and the load 40, respectively, and is used to compare the reference voltage with the voltage of the load 40, outputting a fourth drive signal when the voltage of the load 40 is less than the reference voltage, and outputting a fifth drive signal when the voltage of the load 40 reaches or exceeds the reference voltage. The second current regulation unit 330 is electrically connected to the low-voltage domain current output module 10, the comparison unit 340, and the load 40, respectively, and is used to output a first current to the load 40 according to the fourth drive signal, decrease the magnitude of the first current as the voltage of the load 40 increases, and disconnect the first current output to the load 40 according to the fifth drive signal.

[0090] In the current regulation module 30 of this embodiment, the reference voltage generation unit outputs a reference voltage, the comparison unit 340 compares the reference voltage with the load 40 voltage, and outputs a fourth drive signal or a fifth drive signal according to the comparison result. The second current regulation unit 330 adjusts the first current output by the low-voltage domain current output module 10 according to the fourth drive signal or the fifth signal. Specifically, when the voltage of the load 40 is less than the reference voltage, the comparison unit 340 outputs the fourth drive signal, and the second current regulation unit 330 outputs the first current to the load 40 according to the fourth drive signal, and decreases the magnitude of the first current as the voltage of the load 40 increases; when the voltage of the load 40 reaches or exceeds the reference voltage, the comparison unit outputs the fourth drive signal, and the second current regulation unit 330 disconnects the first current output to the load 40 according to the fifth drive signal.

[0091] Understandably, this embodiment provides a reference voltage as a reference voltage. The comparison unit 340 monitors the voltage of the load 40 and compares the voltage of the load 40 with the reference voltage. Based on different comparison results, the second current adjustment unit 330 is driven to perform corresponding current adjustment actions to achieve precise and controllable adjustment of the first current.

[0092] Optional, please refer to Figure 8 The reference voltage generation unit includes a second current source I2 and a second resistor R2. The positive terminal of the second current source I2 is connected to the supply voltage, and the negative terminal of the second current source I2 is connected to the comparator unit 340. One end of the second resistor R2 is connected to the negative terminal of the second current source I2, and the other end of the second resistor R2 is grounded.

[0093] Understandably, this embodiment adopts a structure similar to the current-driven adjustment unit. A bias circuit is formed by a current source and a resistor. The bias voltage is output as a reference voltage Vcas2 based on the supply voltage. The second resistor R2 can be an adjustable resistor to provide voltage regulation function for the reference voltage.

[0094] Optional, please continue to refer to Figure 8 The comparison unit 340 includes a first comparator U1 and a second comparator U2. The negative input terminal of the first comparator U1 is connected to one end VOUTP of the load 40, the positive input terminal of the first comparator U1 is connected to the reference voltage generation unit, and the output terminal of the first comparator U1 is connected to the second current adjustment unit 330. The negative input terminal of the second comparator U2 is connected to the other end VOUTN of the load 40, the positive input terminal of the second comparator U2 is connected to the reference voltage generation unit, and the output terminal of the first comparator U1 is connected to the second current adjustment unit 330.

[0095] Understandably, in this embodiment, the negative phase of the first comparator U1 is connected to the voltage at one end of the load 40, and its positive phase is connected to the reference voltage output by the reference voltage generation unit 350. After comparing the voltage at one end of the load 40 with the reference voltage, a fourth drive signal or a fifth drive signal is output to the second current adjustment unit 330 based on the comparison result. Correspondingly, in this embodiment, the negative phase of the second comparator U2 is connected to the voltage at the other end of the load 40, and its positive phase is connected to the reference voltage output by the reference voltage generation unit 350. After comparing the voltage at the other end of the load 40 with the reference voltage, a fourth drive signal or a fifth drive signal is output to the second current adjustment unit 330 based on the comparison result. The positive input terminal of the first comparator U1 is connected to the negative terminal of the second current source I2 and one end of the second resistor R2, respectively. The positive input terminal of the second comparator U2 is connected to the negative terminal of the second current source I2 and one end of the second resistor R2, respectively. This embodiment uses the first comparator U1 and the second comparator U2 to achieve precise and controllable high-low voltage switching during the supply of current to the load 40.

[0096] Optional, please refer to Figure 9The second current regulation unit 330 includes a third transistor Ms3 and a fourth transistor Ms4. The drain of the third transistor Ms3 is connected to the low-voltage current output module 10, the source of the third transistor Ms3 is connected to one end VOUTP of the load 40, and the gate of the third transistor Ms3 is connected to the comparator unit 340. The gate of the third transistor Ms3 is connected to the output terminal of the first comparator U1, and the drain of the third transistor Ms3 is connected to the drain of the first power transistor PM0 and the drain of the first ground transistor NM1. The source of the fourth transistor Ms4 is connected to the low-voltage current output module 10, the drain of the fourth transistor Ms4 is connected to the other end VOUTN of the load 40, and the gate of the fourth transistor Ms4 is connected to the comparator unit 340. The gate of the fourth transistor Ms4 is connected to the output terminal of the second comparator U2, and the source of the fourth transistor Ms4 is connected to the drain of the second power transistor PM1 and the drain of the second ground transistor NM2.

[0097] Understandably, both the third transistor Ms3 and the fourth transistor Ms4 are turned on according to the fourth drive signal, so that the first current output by the low-voltage current output module 10 is output to the load 40. Both the third transistor Ms3 and the fourth transistor Ms4 are turned off according to the fifth drive signal, so as to block the first current output by the low-voltage current output module 10. When there is no volume output in a static state, the third transistor Ms3 and the fourth transistor Ms4 have no current output. When the output amplitude is small, the third transistor Ms3 and the fourth transistor Ms4 receive the fourth drive signal output by the comparator unit 340 and are turned on, operating in the linear region. The first current flows through the third transistor Ms3 and the fourth transistor Ms4 and is then output to the load 40. As the voltage of load 40 increases, the impedance of the third transistor Ms3 and the fourth transistor Ms4 gradually increases, and the current flowing through the third transistor Ms3 and the fourth transistor Ms4 gradually decreases. When the voltage of load 40 reaches the reference voltage, the third transistor Ms3 and the fourth transistor Ms4 receive the fifth drive signal output by the comparator unit 340 and turn off, so that the operating current of load 40 is completely provided by the third power transistor PM2 and the fourth power transistor PM3. In addition, the third transistor Ms3 and the fourth transistor Ms4 in this embodiment can prevent the first grounding tube NM1 and the second grounding tube NM2 from being over-voltaged, and can also automatically cut off the path of the low voltage domain under large output.

[0098] In this embodiment, both the third transistor Ms3 and the fourth transistor Ms4 are N-channel field-effect transistors.

[0099] For example, please refer to Figure 10In the driving module, taking the reference voltage signal ng1, the first driving signal Pg1, and the second driving signal phg1 as examples, the signal generation unit 510 includes a fifth transistor Q1. The first conversion unit 520 includes a sixth transistor Q2, a seventh transistor Q3, and an eighth transistor Q4. The second conversion unit 530 includes a ninth transistor Q5, a tenth transistor Q6, and an eleventh transistor Q7.

[0100] The source of the fifth transistor Q1 is grounded. The drain of the sixth transistor Q2 is connected to the drain of the fifth transistor Q1, and the source of the sixth transistor Q2 is connected to node D.

[0101] The source of the seventh transistor Q3 is connected to the drain of the fifth transistor Q1, and the drain of the seventh transistor Q3 is connected to node D.

[0102] The source of the eighth transistor Q4 is connected to the supply voltage, and the drain of the eighth transistor Q4 is connected to node D.

[0103] Correspondingly, the drain of the ninth transistor Q5 is connected to the drain of the fifth transistor Q1, and the source of the ninth transistor Q5 is connected to node E.

[0104] The source of the tenth transistor Q6 is connected to the drain of the fifth transistor Q1, and the drain of the tenth transistor Q6 is connected to node E.

[0105] The source of the eleventh transistor Q7 is connected to the supply voltage, and the drain of the tenth transistor Q6 is connected to node E.

[0106] In this circuit, the drain of the fifth transistor Q1 is used to output a reference voltage signal ng1, which is the output signal of the fifth transistor Q1 and can be output to the first grounding transistor to drive it. Node D is used to output the first drive signal Pg1, and node E is used to output the second drive signal pgh1. When the circuit is working, the fifth transistor Q1 to the eleventh transistor Q7 (Q1~Q7) are each connected to their corresponding drive signals (IN1~IN7). The fifth transistor Q1, the eighth transistor Q4, and the eleventh transistor Q7 are all regarded as current sources, so that the output signal ng1 of the fifth transistor Q1 and the output signal Pg1 of the eighth transistor Q4 form a DC bias, thereby realizing level conversion; correspondingly, the output signal ng1 of the fifth transistor Q1 and the output signal pgh1 of the eleventh transistor Q7 form a DC bias, thereby realizing level conversion.

[0107] Furthermore, the signal generation unit 510, the first conversion unit 520, and the second conversion unit 530 in this embodiment also include another circuit structure that is the same as described above. That is, the same circuit structure is used to convert the reference voltage signal ng2 to DC level to obtain the first driving signal Pg2 and the second driving signal pgh2. Please refer to the circuit structure described above for related details, which will not be repeated here.

[0108] This embodiment also provides a power amplifier, including the power amplifier circuit 100 described above, for amplifying audio signals and outputting them through a load 40.

[0109] Furthermore, this embodiment also provides a chip including the power amplifier circuit 100 described above, used to receive audio signals, perform analog-to-digital conversion, signal pre-amplification, power amplification and other processing on the audio signals, and output them through the load 40.

[0110] It is understood that the power amplifier and chip in this embodiment can achieve a higher output amplitude while ensuring lower power consumption compared to the prior art.

[0111] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this disclosure, and not to limit them; under the concept of this disclosure, the technical features of the above embodiments or different embodiments can also be combined, the steps can be implemented in any order, and there are many other variations of different aspects of this disclosure as described above, which are not provided in detail for the sake of brevity; although this disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this disclosure.

Claims

1. A power amplifier circuit, characterized in that, include: The driver module is used to output synchronized first and second drive signals; A current regulation module is used to receive a first current and output the first current to the load, and when the voltage of the load reaches the target voltage, the magnitude of the first current is gradually reduced as the voltage of the load increases; A low-voltage current output module, electrically connected to the drive module and the current regulation module, is used to receive a low-voltage supply voltage, output the first current according to the first drive signal, and gradually increase the first current as the load voltage increases when the load voltage does not reach the target voltage; and The high-voltage current output module is electrically connected to the drive module and is used to connect to the high-voltage power supply voltage. When the voltage of the load reaches the target voltage, it outputs a second current to the load according to the second drive signal, and gradually increases the magnitude of the second current as the voltage of the load increases. The current regulation module includes: a current regulation drive unit and a first current regulation unit; The current regulation drive unit is used to output a third drive signal, and includes: a first current source, the positive terminal of the first current source is connected to the power supply voltage, the negative terminal of the first current source is connected to the first current regulation unit; and a first resistor, one end of the first resistor is connected to the negative terminal of the first current source, and the other end of the first resistor is grounded. The first current regulation unit, electrically connected to the low-voltage domain current output module, the current regulation drive unit, and the load, is used to output the first current to the load according to the third drive signal, and gradually decrease the magnitude of the first current as the voltage of the load increases when the voltage of the load reaches the target voltage. It includes: a first transistor, the drain of which is connected to the low-voltage domain current output module, the source of which is connected to one end of the load, and the gate of which is connected to the current regulation drive unit; and a second transistor, the source of which is connected to the low-voltage domain current output module, the drain of which is connected to the other end of the load, and the gate of which is connected to the current regulation drive unit.

2. The power amplifier circuit according to claim 1, characterized in that, The driving module includes: Signal generation unit, used to generate reference voltage signal; A first conversion unit, electrically connected to both the signal generation unit and the low-voltage domain current output module, is used to acquire the reference voltage signal, convert the reference voltage signal into a first drive signal, and output the first drive signal to the low-voltage domain current output module; and The second conversion unit is electrically connected to both the signal generation unit and the high-voltage domain current output module. It is used to acquire the reference voltage signal, convert the reference voltage signal into a second driving signal, and output the second driving signal to the high-voltage domain current output module. The voltage of the second driving signal is greater than the voltage of the first driving signal.

3. The power amplifier circuit according to claim 1, characterized in that, The current regulation module is also used to disconnect the first current output to the load when the voltage of the load exceeds the reference voltage.

4. The power amplifier circuit according to claim 3, characterized in that, The current regulation module includes: A reference voltage generation unit is used to generate the reference voltage; A comparison unit, electrically connected to both the reference voltage generation unit and the load, is used to compare the reference voltage with the load voltage, and output a fourth drive signal when the load voltage is less than the reference voltage, and output a fifth drive signal when the load voltage reaches or exceeds the reference voltage; and The second current regulation unit is electrically connected to the low-voltage current output module, the comparison unit, and the load, respectively. It is used to output the first current to the load according to the fourth drive signal, reduce the magnitude of the first current as the voltage of the load increases, and disconnect the first current output to the load according to the fifth drive signal.

5. The power amplifier circuit according to claim 4, characterized in that, The reference voltage generation unit includes: A second current source, the positive terminal of which is connected to the supply voltage, and the negative terminal of which is connected to the comparison unit; and The second resistor has one end connected to the negative terminal of the second current source and the other end grounded.

6. The power amplifier circuit according to claim 4, characterized in that, The comparison unit includes: A first comparator, wherein the negative input terminal of the first comparator is connected to one end of the load, the non-inverting input terminal of the first comparator is connected to the reference voltage generation unit, and the output terminal of the first comparator is connected to the second current regulation unit; and The second comparator has its negative input connected to the other end of the load, its positive input connected to the reference voltage generation unit, and its output connected to the second current regulation unit.

7. The power amplifier circuit according to claim 4, characterized in that, The second current regulating unit includes: A third transistor, the drain of which is connected to the low-voltage current output module, the source of which is connected to one end of the load, and the gate of which is connected to the comparator unit; and The fourth transistor has its source connected to the low-voltage current output module, its drain connected to the other end of the load, and its gate connected to the comparator unit.

8. A power amplifier, characterized in that, Includes the power amplifier circuit as described in any one of claims 1 to 7.

9. A chip, characterized in that, Includes the power amplifier circuit as described in any one of claims 1 to 7.

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