Power amplification circuit and control method thereof

Abstract

The invention discloses a power amplification circuit and a control method thereof. The power amplification circuit comprises an output stage switch network; the output stage switching network comprises at least two pull-up modules; the pull-up module comprises a first power supply input end, a first signal input end, an enabling end and a first output end; the pull-up module is configured to connect or disconnect the first power supply input end and the first output end according to a signal of the first signal input end when the enable end is enabled; wherein the first output ends of different pull-up modules are electrically connected, and the voltages input by at least two first power input ends are different. The loss of the power amplification circuit can be reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of power amplification, and in particular to a power amplification circuit and a control method thereof. Background Art

[0002] Power amplifier circuits have important applications in modern electronic technology. Among the many types of power amplifier circuits, some power amplifier circuits that use switching power tubes in the output stage have lower losses than linear power amplifier circuits, and are therefore widely used.

[0003] However, the power amplifier circuit using a switching power tube in the output stage still has relatively high losses. Therefore, how to further reduce the losses of the power amplifier circuit has become an urgent problem to be solved. Summary of the invention

[0004] The invention provides a power amplifier circuit and a control method thereof to reduce the loss of the power amplifier circuit.

[0005] According to one aspect of the present invention, a power amplifier circuit is provided, the power amplifier circuit comprising an output stage switch network; the output stage switch network comprises at least two pull-up modules;

[0006] The pull-up module comprises a first power input terminal, a first signal input terminal, an enable terminal and a first output terminal; the pull-up module is configured to turn on or off the first power input terminal and the first output terminal according to a signal of the first signal input terminal when the enable terminal is enabled;

[0007] The first output ends of different pull-up modules are electrically connected, and the voltages input to at least two of the first power input ends are different.

[0008] Optionally, the at least two pull-up modules include a first pull-up module and at least one second pull-up module; a voltage input to the first power input terminal corresponding to the first pull-up module is greater than a voltage input to the first power input terminal corresponding to the second pull-up module;

[0009] The second pull-up module includes an anti-backflow unit, and the anti-backflow unit is used to prevent a first power input terminal corresponding to the first pull-up module from being short-circuited with a first power input terminal corresponding to the second pull-up module.

[0010] Optionally, the first pull-up module includes a first switch unit, a first end of the first switch unit is electrically connected to a first power input end of the first pull-up module, and a second end of the first switch unit is electrically connected to a first output end of the first pull-up module;

[0011] The second pull-up module further includes a second switch unit; the second switch unit and the backflow prevention unit are connected in series between the first power input terminal of the second pull-up module and the first output terminal of the second pull-up module.

[0012] Optionally, the backflow prevention unit includes a third switch unit; the control end of the third switch unit is electrically connected to the enable end of the second pull-up module; the control end of the second switch unit is electrically connected to the signal input end of the second pull-up module.

[0013] Optionally, the backflow prevention unit includes a unidirectional conduction unit, and the unidirectional conduction unit and the second switch unit are connected in series between the first power input end of the second pull-up module and the first output end of the second pull-up module;

[0014] The second pull-up module also includes a first logic unit, a first input end of the first logic unit is electrically connected to the enable end of the second pull-up module, a second input end of the first logic unit is electrically connected to the signal input end of the second pull-up module, and an output end of the first logic unit is electrically connected to the control end of the second switch unit; the first logic unit is configured to output the signal of its second input end to its output end when its first input end is enabled.

[0015] Optionally, the first pull-up module also includes a second logic unit, a first input end of the second logic unit is electrically connected to the enable end of the first pull-up module, a second input end of the second logic unit is electrically connected to the signal input end of the first pull-up module, and an output end of the second logic unit is electrically connected to the control end of the first switch unit; the second logic unit is configured to output the signal of its second input end to its output end when its first input end is enabled.

[0016] Optionally, the power amplifier circuit further includes a control module, the control module including a control terminal and at least two enable output terminals electrically connected to the enable terminals of the at least two pull-up modules in a one-to-one correspondence;

[0017] The control module is configured to output an enable signal from the enable output terminal according to a control signal from the control terminal.

[0018] Optionally, the at least two pull-up modules include a first pull-up module and a second pull-up module; the control module includes: a first rising edge delay unit, a first logic AND unit, a first level conversion unit, an inverter unit, a second rising edge delay unit, a second logic AND unit and a second level conversion unit;

[0019] The first end of the first rising edge delay unit is electrically connected to the control end of the control module, the second end of the first rising edge delay unit is electrically connected to the first input end of the first logic and unit; the second input end of the first logic and unit is electrically connected to the control end of the control module, the output end of the first logic and unit is electrically connected to the input end of the first level conversion unit; the output end of the first level conversion unit is electrically connected to the enable end corresponding to the first pull-up module;

[0020] The input end of the inverter unit is electrically connected to the control end of the control module, the first end of the second rising edge delay unit is electrically connected to the output end of the inverter unit, the second end of the second rising edge delay unit is electrically connected to the first input end of the second logic AND unit; the second input end of the second logic AND unit is electrically connected to the output end of the inverter unit, the output end of the second logic AND unit is electrically connected to the input end of the second level conversion unit; the output end of the second level conversion unit is electrically connected to the enable end corresponding to the second pull-up module.

[0021] Optionally, the output stage switch network further includes at least two pull-down modules corresponding one-to-one to the at least two pull-up modules;

[0022] The pull-down module comprises a second power input terminal, a second signal input terminal and a second output terminal; the pull-down module is configured to connect or disconnect the second power input terminal and the second output terminal according to a signal of the second signal input terminal;

[0023] Wherein, the second output terminal of the pull-down module is electrically connected to the first output terminal of the pull-up module. Optionally, the power amplifier circuit further includes a filtering module, a triangular wave generating module and a comparing module;

[0024] The first input end of the comparison module is electrically connected to the triangle wave generation module, the second input end of the comparison module is used to access the signal to be amplified, and the output end of the comparison module is electrically connected to the first signal input end of the pull-up module;

[0025] The input end of the filter module is electrically connected to the first output end of the pull-up module, and the output end of the filter module is electrically connected to the output end of the power amplifier circuit.

[0026] According to another aspect of the present invention, a control method for a power amplifier circuit is provided, which is applied to the power amplifier circuit as described above. The control method for the power amplifier circuit includes:

[0027] Obtaining a target strength of an output signal of a power amplifier circuit;

[0028] An enable terminal of a preset pull-up module is enabled according to the target strength.

[0029] The technical solution of the embodiment of the present invention adopts a power amplifier circuit including an output stage switch network; the output stage switch network includes at least two pull-up modules; the pull-up module includes a first power input terminal, a first signal input terminal, an enable terminal and a first output terminal; the pull-up module is configured to turn on or off the first power input terminal and the first output terminal according to the signal of the first signal input terminal when the enable terminal is enabled; wherein the first output terminals of different pull-up modules are electrically connected, and the voltages input to at least two first power input terminals are different. By setting at least two pull-up modules, and inputting different voltages (i.e., working voltages) to the corresponding first power input terminals, the corresponding pull-up module can be selected to be enabled as needed during operation, and then in some cases, a smaller working voltage can be selected to power the output terminal of the output stage switch network, so that the loss of the parasitic capacitor can be reduced, that is, the loss of the power amplifier circuit can be reduced.

[0030] It should be understood that the contents described in this section are not intended to identify the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0032] Figure 1 A schematic diagram of a circuit structure of a power amplifier circuit provided by an embodiment of the present invention;

[0033] Figure 2 A schematic diagram of the overall circuit structure of a power amplifier circuit provided by an embodiment of the present invention;

[0034] Figure 3 A schematic diagram of the circuit structure of another power amplifier circuit provided by an embodiment of the present invention;

[0035] Figure 4 A schematic diagram of the circuit structure of another power amplifier circuit provided by an embodiment of the present invention;

[0036] Figure 5 A schematic diagram of the circuit structure of another power amplifier circuit provided by an embodiment of the present invention;

[0037] Figure 6 A schematic diagram of the circuit structure of another power amplifier circuit provided by an embodiment of the present invention;

[0038] Figure 7 A schematic diagram of the circuit structure of another power amplifier circuit provided by an embodiment of the present invention;

[0039] Figure 8 A schematic diagram of the circuit structure of another power amplifier circuit provided by an embodiment of the present invention;

[0040] Fig. 9 A schematic diagram of the circuit structure of another power amplifier circuit provided by an embodiment of the present invention;

[0041] Fig.10 A schematic diagram of the circuit structure of another power amplifier circuit provided by an embodiment of the present invention;

[0042] Fig.11 A schematic diagram of the circuit structure of another power amplifier circuit provided by an embodiment of the present invention;

[0043] Fig.12 A schematic diagram of a circuit structure of a control module provided in an embodiment of the present invention;

[0044] Fig.13 for Fig.11 Timing diagram of

[0045] Fig.14 A timing diagram of a power amplifier circuit provided by an embodiment of the present invention;

[0046] Fig.15 The present invention provides a flow chart of a method for controlling a power amplifier circuit according to an embodiment of the present invention. DETAILED DESCRIPTION

[0047] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0048] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0049] As the power amplifier circuit in the related art has the problem of high loss, the inventor found through extensive research that the reason for this technical problem is that for the power amplifier circuit with a power switch tube at the output stage, there is parasitic capacitance at the output stage, and the parasitic capacitance charge and discharge loss is an important source of loss in the power amplifier circuit. The loss formula of parasitic capacitance is: 0.5*C out *V PP 2 , where C out is the capacitance value of the parasitic capacitor, V pp is the power supply of the power switch tube. From the loss formula, it can be seen that the loss is proportional to the square of the power supply, and in the related technology, the power supply is large, which also makes the loss of the power amplifier circuit large.

[0050] In view of the above technical problems, the present invention proposes the following solutions:

[0051] Figure 1 A schematic diagram of a circuit structure of a power amplifier circuit provided by an embodiment of the present invention, referring to Figure 1 The power amplifier circuit includes an output stage switch network; the output stage switch network includes at least two pull-up modules 11; the pull-up module 11 includes a first power input terminal V, a first signal input terminal IN, an enable terminal EN and a first output terminal; the pull-up module 11 is configured to turn on or off the first power input terminal V and the first output terminal according to the signal of the first signal input terminal IN when the enable terminal EN is enabled; wherein the first output terminals of different pull-up modules 11 are electrically connected, and the voltages input to at least two first power input terminals V are different.

[0052] Specifically, the power amplifier circuit in this embodiment is a power amplifier circuit whose output stage includes a power switch tube, such as a class D power amplifier circuit. For ease of understanding, the overall structure of a class D power amplifier circuit is briefly introduced first. Figure 2 As shown, Figure 2The overall circuit structure diagram of a power amplifier circuit provided by an embodiment of the present invention includes a triangular wave generating module 3, a comparing module 2, an output stage switch network 1 and a filtering module 13. The output end of the triangular wave generating module 3 is electrically connected to the first input end of the comparing module 2, and the second input end Vin of the comparing module 2 inputs the signal to be amplified. The output end of the comparing module 2 is electrically connected to the signal input end of the output stage switch network 1, the output end of the output stage switch network 1 is electrically connected to the input end of the filtering module 13, and the output end of the filtering module 13 is electrically connected to the output end Vout of the power amplifier circuit. The comparing module 2 is equivalent to using a triangular wave to sample the signal to be amplified. According to the sampling result, the switch in the output stage switch network 1 is turned on or off, thereby generating a pulse width modulation signal, that is, a pulse width modulation signal is generated at the output end VPWM of the output stage switch network 1. After filtering by the filtering module 13, a waveform amplified by a certain multiple relative to the signal to be amplified is obtained, and is output from the output end Vout of the power amplifier circuit.

[0053] In this embodiment, the output stage switch network 1 includes at least two pull-up modules 11, such as Figure 1As shown, the output stage switch network 1 exemplarily includes a first pull-up module 11 (1) to an nth pull-up module 11 (n), a total of n pull-up modules 11, n ≥ 2. Each pull-up module 11 has a first power input terminal V, a first signal input terminal IN and an enable terminal EN, and the first signal input terminals IN of different pull-up modules 11 can be electrically connected to the output terminal of the comparison module 2. When the enable terminal EN of a certain pull-up module 11 is enabled, the pull-up module 11 can be turned on or off according to the output signal of the comparison module 2. When the pull-up module 11 is turned on, the corresponding first power input terminal V is turned on with the output terminal VPWM of the output stage switch network 1, so that the output signal of the output stage switch network 1 is a high level. When the pull-up module 11 is turned off, the output signal of the output stage switch network 1 is a low level. The loss of the parasitic capacitance of the output stage switch module 1 is proportional to the square of the working voltage of the first power input terminal V input. In this embodiment, since at least two pull-up modules 11 are provided, and the voltages of at least two first power input terminals V input are different, it is preferred that the voltage of each first power input terminal V input is different. During the operation of the power amplifier circuit, the corresponding pull-up module 11 can be enabled according to the specific situation, so that different working voltages are used in different situations, which can ensure that the power amplifier circuit can normally amplify the signal to be amplified, and the loss of the power amplifier circuit can be reduced. For example, in the case of a large signal (the output signal of the power amplifier circuit is large), the pull-up module 11 with a larger working voltage of the first power input terminal V input is selected to be enabled, so that the output signal of the power amplifier circuit can reach the corresponding strength. In the case of a small signal (the output signal of the power amplifier circuit is small), the pull-up module 11 with a smaller working voltage of the first power input terminal V input is selected to be enabled, which can ensure that the output signal of the power amplifier circuit can reach the corresponding strength, and according to the loss formula of the parasitic capacitance, the loss can be reduced compared to using a larger working voltage. Therefore, the power amplifier circuit of this embodiment can amplify the signal to be amplified normally and have a small loss.

[0054] In addition, in some embodiments, the corresponding pull-up module 11 can be selected and enabled according to the target strength of the output signal of the power amplifier circuit. Specifically, the pull-up module corresponding to the working voltage greater than the target strength of the output signal and closest to the target strength can be selected and enabled, thereby ensuring that the signal to be amplified can be amplified normally and with less loss.

[0055] The technical solution of this embodiment adopts a power amplifier circuit including an output stage switch network; the output stage switch network includes at least two pull-up modules; the pull-up module includes a first power input terminal, a first signal input terminal, an enable terminal and a first output terminal; the pull-up module is configured to turn on or off the first power input terminal and the first output terminal according to the signal of the first signal input terminal when the enable terminal is enabled; wherein the first output terminals of different pull-up modules are electrically connected, and the voltages input to at least two first power input terminals are different. By setting at least two pull-up modules, and inputting different voltages (i.e., working voltages) to the corresponding first power input terminals, the corresponding pull-up module can be selected to be enabled as needed during operation, and then in some cases, a smaller working voltage can be selected to power the output terminal of the output stage switch network, so that the loss of the parasitic capacitor can be reduced, that is, the loss of the power amplifier circuit can be reduced.

[0056] The above is the core idea of ​​the present invention, and several specific implementation methods of the present invention will be introduced below.

[0057] Optionally, Figure 3 A schematic diagram of a circuit structure of another power amplifier circuit provided by an embodiment of the present invention, referring to Figure 3 The at least two pull-up modules 11 include a first pull-up module 11A and at least one second pull-up module 11B; the voltage input to the first power input terminal corresponding to the first pull-up module 11A is greater than the voltage input to the first power input terminal corresponding to the second pull-up module. The second pull-up module 11B includes an anti-backflow unit 112B, which is used to prevent the first power input terminal corresponding to the first pull-up module 11A from short-circuiting with the first power input terminal corresponding to the second pull-up module 11B.

[0058] Specifically, among the first power input terminals corresponding to all the pull-up modules of the power amplifier circuit, the voltage input to the first power input terminal of the first pull-up module 11A is the largest. When the first power input terminal VPP of the first pull-up module 11A is turned on with the first output terminal, and the first power input terminal VDD of the second pull-up module 11A is turned off with the first output terminal, the voltage difference between the voltage of the first power input terminal VPP corresponding to the first pull-up module 11A and the voltage of the first power input terminal VDD corresponding to the second pull-up module 11B may cause the parasitic diode in the second pull-up module 11B to be turned on, thereby causing the first power input terminal VPP of the first pull-up module 11A to be short-circuited with the first power input terminal VDD of the second pull-up module 11B. Alternatively, when there is a competition risk between the enable signals corresponding to the enable terminals of any two pull-up modules, so that the two pull-up modules are turned on at the same time, there is a voltage difference between the voltages of the first power input terminals corresponding to the two pull-up modules, which may still cause the parasitic diode in the pull-up module with a smaller voltage at the first power input terminal to be turned on, thereby causing the first power input terminals of the two pull-up modules to be short-circuited. In this embodiment, by setting an anti-backflow unit 112B in the second pull-up module 11B, there is an anti-backflow unit 112B between any two first power input terminals with a voltage difference, which can prevent current from being generated between the first power input terminal with a large voltage and the first power input terminal with a small voltage, causing the two first power input terminals to short-circuit.

[0059] Optionally, continue to refer to Figure 3 The first pull-up module 11A includes a first switch unit 111A, a first end of the first switch unit 111A is electrically connected to a first power input end of the first pull-up module 11A, and a second end of the first switch unit 111A is electrically connected to a first output end of the first pull-up module 11A. The second pull-up module 11B includes a second switch unit 111B and an anti-backflow unit 112B; the second switch unit 111B and the anti-backflow unit 112B are connected in series between a first power input end of the second pull-up module 11B and a first output end of the second pull-up module 11B.

[0060] Specifically, in this embodiment, the n pull-up modules 11 include a first pull-up module 11A and n-1 second pull-up modules 11B. The voltage input to the first power input terminal corresponding to the first pull-up module 11A is the highest. For easy distinction, the first power input terminal of the first pull-up module 11A is marked as the first first power input terminal VPP, and the first power input terminal of the second pull-up module 11B is marked as the second first power input terminal VDD. The voltage of the first first power input terminal VPP is greater than the voltage of any second first power input terminal VDD. When the first pull-up module 11A is enabled, the first first power input terminal VPP will be short-circuited with the second first power input terminal VDD through the parasitic diode of the second switch unit 111B, and by setting the anti-backflow module 112B, the anti-backflow module 112B is unidirectionally cut off between the first first power input terminal VPP and the second first power input terminal VDD when the corresponding second pull-up module 11B is not enabled, so as to prevent the first first power input terminal VPP from being short-circuited with the second first power input terminal VDD.

[0061] Optionally, in some embodiments, Figure 3 As shown, the first end of the anti-backflow module 112B is electrically connected to the second first power input terminal VDD, the second end of the anti-backflow module 112B is electrically connected to the first end of the second switch unit 111B, and the second end of the second switch unit 111B is electrically connected to the first output end of the second pull-up module 11B. When the corresponding second pull-up module of the anti-backflow module 112B is not enabled, the current direction flowing from the second end to the first end is cut off.

[0062] Optionally, in some other embodiments, the first end of the second switch unit 111B may be electrically connected to the second first power input terminal VDD, the second end of the second switch unit 111B may be electrically connected to the first end of the anti-backflow unit 112B, and the second end of the anti-backflow unit 112B may be electrically connected to the first output end of the second pull-up module 11B. When the corresponding second pull-up module of the anti-backflow module 112B is not enabled, the current direction flowing from the second end to the first end is cut off.

[0063] Further optionally, Figure 4 A schematic diagram of a circuit structure of another power amplifier circuit provided by an embodiment of the present invention, referring to Figure 4 The backflow prevention unit includes a third switch unit 1121B; a control end of the third switch unit 1121B is electrically connected to an enable end of the second pull-up module 11B, and a control end of the second switch unit 111B is electrically connected to a signal input end of the second pull-up module 11B.

[0064] Specifically, in this embodiment, the third switch unit 1121B is used to realize the function of the backflow prevention unit, and can also control the connection state between the second first power input terminal VDD and the first output terminal of the second pull-up module, thereby determining whether the second pull-up module is enabled. In this embodiment, the unidirectional conduction characteristic of the parasitic diode of the third switch unit 1121B is used to block the current flowing from the first first power input terminal VPP to the second first power input terminal VDD. Therefore, the anode of the parasitic diode of the third switch unit 1121B is connected to the second first power input terminal VDD, and the cathode is connected to the first first power input terminal VPP.

[0065] For example, in Figure 4 In the illustrated embodiment, a first end of the third switch unit 1121B is electrically connected to the second first power input terminal VDD, a second end of the third switch unit 1121B is electrically connected to a first end of the second switch unit 111B, and a second end of the second switch unit 111B is electrically connected to a first output terminal of the second pull-up module.

[0066] Further optionally, if Figure 5 As shown, Figure 5 A schematic diagram of the circuit structure of another power amplifier circuit provided by an embodiment of the present invention. Figure 5 Only one second pull-up module is illustrated. In this embodiment, the first switch unit 111A includes a first transistor T1, the drain of the first transistor T1 is electrically connected to the first first power input terminal VPP, the source of the first transistor T1 is electrically connected to the output terminal of the first pull-up module, and the control electrode of the first transistor T1 serves as the control terminal of the first switch unit 111A. The second switch unit 111B includes a second transistor T2, the drain of the second transistor T2 serves as the first terminal of the second switch unit 111B, the source of the second transistor T2 serves as the second terminal of the second switch unit 111B, and the gate of the second transistor T2 serves as the control terminal of the second switch unit 111B. The third switch unit 1121B includes a third transistor T3, the source of the third transistor T3 serves as the second terminal of the third switch unit 1121B, and the gate of the third transistor T3 serves as the control terminal of the third switch unit 1121B. Each of the above transistors can be an N-type transistor or a P-type transistor.

[0067] Optionally, refer to Figures 3 to 5, the gate of each transistor can be electrically connected to the corresponding enable terminal or signal input terminal through the driving unit 90. The driving unit 90 includes a driving circuit 901, which can modulate the enable signal inputted from the enable terminal EN into a signal capable of driving the transistor to work. And the driving circuit 901 can modulate the signal inputted from the signal input terminal IN into a signal capable of driving the transistor to work. The types of driving circuits 901 are various, and their specific circuit structures and implementation methods are well known to those skilled in the art, and will not be described in detail here.

[0068] Further, continue to refer to Figure 5 Each driving circuit 901 includes a power supply terminal and a ground terminal. The power supply terminal of each driving circuit 901 is electrically connected to a second first power supply input terminal VDD, and the ground terminal of the driving circuit 901 can be connected to the first output terminal of the pull-up module, or to the ground, or to the third power supply input terminal VCP.

[0069] Further, continue to refer to Figure 5 The power amplifier circuit further includes a bootstrap capacitor Cboot, a first end of the bootstrap capacitor Cboot is electrically connected to a second first power input terminal VDD through a diode, and a second end of the bootstrap capacitor Cboot is electrically connected to a first output terminal of the pull-up module. The functions of the bootstrap capacitor Cboot and the diode are well known to those skilled in the art and will not be described in detail herein.

[0070] Optionally, refer to Figures 3 to 5 The first pull-up module 11A further includes a second logic unit 112A, a first input terminal of the second logic unit 112A is electrically connected to the enable terminal EN(1) of the first pull-up module, a second input terminal of the second logic unit 112A is electrically connected to the signal input terminal IN(1) of the first pull-up module, and an output terminal of the second logic unit 112A is electrically connected to the control terminal of the first switch unit 111A, and specifically can be electrically connected to the control terminal of the first switch unit 111A via a driving unit 90. The second logic unit 112A is configured to output the signal of its second input terminal to its output terminal when its first input terminal is enabled.

[0071] Specifically, when the first switch unit 111A uses an N-type transistor, the second logic unit 112A is implemented by a second AND gate AN2, and the effective level of the enable signal is a high level. When the enable signal is a high level, the signal input by the signal input terminal IN(1) can be output to the control terminal of the first switch unit 111A, thereby controlling the first switch unit 111A to be turned on or off.

[0072] When the first switch unit 111A adopts a P-type transistor, the second logic unit 112A can be implemented by an OR gate, and the effective level of the enable signal is a low level. When the enable signal is a low level, the signal input by the signal input terminal IN(1) can be output to the control terminal of the first switch unit 111A, thereby controlling the first switch unit 111A to be turned on or off.

[0073] Alternatively, if Figure 6 As shown, Figure 6 A schematic diagram of the circuit structure of another power amplifier circuit provided by an embodiment of the present invention. Figure 5 The structure shown is different in that Figure 6 Two second pull-up modules 11B are schematically shown. The two second pull-up modules are, for example, respectively defined as a first second pull-up module 11B(1) and a second second pull-up module 11B(2), and the corresponding first power input terminals are respectively marked as the second first power input terminal VDD(1) and the second second first power input terminal VDD(2). Different second pull-up modules 11B have the same specific circuit structure, and the corresponding first power input terminals VDD are connected to different voltages. When the target strength of the output signal of the power amplifier circuit is different, the corresponding pull-up module can be selected to be turned on as needed. For example, the voltage of the second second first power input terminal VDD(2) is less than the voltage of the second first power input terminal VDD(1). When the target strength of the output signal is less than the voltage of the second second first power input terminal VDD(2), the second second first pull-up module 11B(2) can be controlled to be enabled, and the other pull-up modules can be disabled. When the target strength of the output signal is greater than the voltage of the second first power input terminal VDD(2) and less than the voltage of the second first power input terminal VDD(1), the second first pull-up module 11B(1) can be controlled to be enabled, and other pull-up modules can be disabled. When the target strength of the output signal is greater than the voltage of the second first power input terminal VDD(1) and less than the voltage of the first first power input terminal VPP, the first first pull-up module 11A can be controlled to be enabled, and other pull-up modules can be disabled.

[0074] Furthermore, if Figure 6 As shown, each driving circuit 901 includes a power supply terminal and a ground terminal. The power supply terminal of each driving circuit 901 is electrically connected to a second first power input terminal VDD (such as the second first power input terminal VDD(1) or the second second first power input terminal VDD(2)), and the ground terminal of the driving circuit 901 can be connected to the first output terminal of the pull-up module, or to the ground, or to the third power input terminal VCP.

[0075] Alternatively, in some other embodiments, such as Figure 7 As shown, Figure 7A schematic diagram of the circuit structure of another power amplifier circuit provided by an embodiment of the present invention. In this embodiment, the first end of the second switch unit 111B is electrically connected to the second first power input terminal VDD, the second end of the second switch unit 111B is electrically connected to the first end of the third switch unit 1121B, and the second end of the third switch unit 1121B is electrically connected to the first output end of the second pull-up module. Figure 8 As shown, Figure 8 A schematic diagram of the circuit structure of another power amplifier circuit provided by an embodiment of the present invention. In this embodiment, each switch unit is implemented by a specific transistor. Of course, it can be understood that Figure 8 In the example, a second pull-up module is included. In other embodiments, similar Figure 6 The structure includes at least two second pull-up modules.

[0076] In the above embodiments, the backflow prevention units are all implemented in the form of switch units, which has the effect of simple circuit structure.

[0077] Alternatively, in some other embodiments, Fig. 9 A circuit structure diagram of another power amplifier circuit provided by an embodiment of the present invention, Fig.10 A schematic diagram of a circuit structure of another power amplifier circuit provided by an embodiment of the present invention, referring to Fig. 9 and Fig.10 . In this embodiment, the backflow prevention unit includes a unidirectional conduction unit 1122B, and the unidirectional conduction unit 1122B and the second switch unit 111B are connected in series between the second first power input terminal VDD and the first output terminal of the second pull-up module. The second pull-up module also includes a first logic unit 1123B, the first input terminal of the first logic unit 1123B is electrically connected to the enable terminal of the second pull-up module, the second input terminal of the first logic unit 1123B is electrically connected to the signal input terminal of the second pull-up module, and the output terminal of the first logic unit 1123B is electrically connected to the control terminal of the second switch unit 111B; the first logic unit 1123B is configured to output the signal of its second input terminal to its output terminal when its first input terminal is enabled.

[0078] Specifically, in this embodiment, the anti-backflow unit is implemented in the form of a unidirectional conduction unit 1122B. The unidirectional single-pass unit 1122B has a unidirectional conduction function and can only be conducted in the direction from the end connected to the second first power input terminal VDD to the end connected to the first output terminal of the second pull-up module. Further, in order to enable the second pull-up module 11B, a first logic unit 1123B is set. Similar to the second logic unit 112A, when the second switch unit 111B adopts an N-type transistor, the first logic unit 1123B is implemented by a first AND gate AN1, and the effective level of the enable signal is a high level. When the enable signal is a high level, the signal input by the signal input terminal IN can be output to the control terminal of the second switch unit 111B, thereby controlling the second switch unit 111B to be turned on or off.

[0079] When the second switch unit 111B uses a P-type transistor, the first logic unit 1123B can be implemented by an OR gate, and the effective level of the enable signal is a low level. When the enable signal is a low level, the signal input by the signal input terminal IN can be output to the control terminal of the second switch unit 111B, thereby controlling the second switch unit 111B to be turned on or off.

[0080] Optionally, continue to refer to Fig.10 In this embodiment, the unidirectional conductive unit 1122B includes an inverter F1. Fig.10 As shown, the first end of the one-way conducting unit 1122B is electrically connected to the second first power input terminal VDD, the second end of the one-way conducting unit 1122B is electrically connected to the first end of the second switch unit 111B, and the second end of the second switch unit 111B is electrically connected to the first output terminal of the second pull-up module. In some other embodiments, the first end of the second switch unit 111B can also be electrically connected to the second first power input terminal VDD, the second end of the second switch unit 111B is electrically connected to the first end of the one-way conducting unit 1122B, and the second end of the one-way conducting unit 1122B is electrically connected to the first output terminal of the second pull-up module. Of course, Fig.10 The embodiment of the present invention may include a second pull-up module. In some other embodiments, the embodiment of the present invention may include at least two second pull-up modules.

[0081] Optionally, refer to Figure 5 , Figure 6 , Figure 8 and Fig.10The output stage switch network further includes at least two pull-down modules corresponding to the at least two pull-up modules 11. The at least two pull-down modules 12 include a first pull-down module 12A corresponding to the first pull-up module 11A, and a second pull-down module 12B corresponding to the second pull-up module 11B. The pull-down module includes a second power input terminal, a second signal input terminal and a second output terminal; the pull-down module is configured to turn on or off the second power input terminal and the second output terminal according to a signal at the second signal input terminal; the second output terminal of the pull-down module is electrically connected to the first output terminal of the pull-up module.

[0082] Specifically, in the present embodiment, the pull-down module provides a low level for the output terminal VPWM of the output stage switch network, and the second power supply input terminal is grounded, for example. When the pull-down module is turned on, the output terminal VPWM of the output stage switch network is pulled low. The signal input terminal of the pull-down module can be electrically connected to the signal input terminal of the corresponding pull-up module. The pull-down module may include a fourth switch unit, wherein the fourth switch unit in the first pull-down module 12A is marked as the first fourth switch unit 121A, and the fourth switch unit in the second pull-down module is marked as the second fourth switch unit 121B. The fourth switch unit may include a transistor, which may be a P-type transistor or an N-type transistor. It should be noted that, Figure 6 As shown, each second pull-up module corresponds to a second pull-down module 12B.

[0083] Optionally, Fig.11 A schematic diagram of a circuit structure of another power amplifier circuit provided by an embodiment of the present invention, referring to Fig.11 The power amplifier circuit further includes a control module 30, which includes a control terminal CTRL and at least two enable output terminals electrically connected to the enable terminals of at least two pull-up modules in a one-to-one correspondence. The control module 30 is configured to output an enable signal from the enable output terminal according to a control signal from the control terminal.

[0084] Specifically, the control signal can be output by a controller electrically connected to the power amplifier circuit, and the control module 30 enables one of the pull-up modules according to the control signal when working. Specifically, the pull-up module corresponding to the working voltage that is greater than the target strength of the output signal and closest to the target strength can be selected to be enabled, thereby ensuring that the signal to be amplified can be amplified normally and with less loss.

[0085] Optional, Fig.12 A schematic diagram of a circuit structure of a control module provided in an embodiment of the present invention, referring to Fig.12In this embodiment, the power amplifier circuit includes two pull-up modules, a first pull-up module and a second pull-up module. In this case, the control module 30 may include: a first rising edge delay unit 301, a first logic AND unit 302, a first level conversion unit 303, an inverter unit 304, a second rising edge delay unit 305, a second logic AND unit 306, and a second level conversion unit 307.

[0086] The first end of the first rising edge delay unit 301 is electrically connected to the control end CTRL of the control module 30, and the second end of the first rising edge delay unit 301 is electrically connected to the first input end of the first logic AND unit 302; the second input end of the first logic AND unit 302 is electrically connected to the control end CTRL of the control module 30, and the output end of the first logic AND unit 302 is electrically connected to the input end of the first level conversion unit 303; the output end of the first level conversion unit is electrically connected to the enable end of the corresponding first pull-up module;

[0087] The input end of the inverter unit 304 is electrically connected to the control end CTRL of the control module 30, the first end of the second rising edge delay unit 305 is electrically connected to the output end of the inverter unit 304, the second end of the second rising edge delay unit 305 is electrically connected to the first input end of the second logic AND unit 306; the second input end of the second logic AND unit 306 is electrically connected to the output end of the inverter unit 304, the output end of the second logic AND unit 306 is electrically connected to the input end of the second level conversion unit 307; the output end of the second level conversion unit 307 is electrically connected to the enable end of the corresponding second pull-up module. The above-mentioned level conversion unit can convert the level of the power supply end into the level required by the enable signal, such as an amplitude modulation circuit.

[0088] Specifically, Fig.13 for Fig.12 For the timing diagram, refer to Fig.12 and Fig.13 When the control terminal CTRL is at a low level, the two input terminals of the first logic AND unit 302 are both at a low level, then the input terminal of the first level conversion unit 303 is at a low level, and the output terminal is also at a low level, wherein the output terminal of the first level conversion unit 303 is electrically connected to the enable terminal of the first pull-up module; and the two input terminals of the second logic AND unit 306 are both at a high level, thus the input terminal of the second level conversion unit 307 is at a high level, and the output terminal is also at a high level, wherein the output terminal of the second level conversion unit 303 is electrically connected to the enable terminal of the second pull-up module.

[0089] When the rising edge of the control terminal CTRL arrives, the input terminal of the second logic AND unit 306 will immediately jump to a low level, but due to the delay effect of the first rising edge delay unit 301, the first input terminal of the first logic AND unit 302 will jump to a high level after a certain delay, so the output terminal of the first logic AND unit 302 will jump to a high level after a certain delay, so that the output of the first level conversion unit 303 is a high level.

[0090] When the falling edge of the control terminal CTRL arrives, the input terminal of the first logic AND unit 302 will immediately jump to a low level, but due to the delay effect of the second rising edge delay unit 305, the first input terminal of the second logic AND unit 306 will jump to a high level after a certain delay, so the output terminal of the second logic AND unit 306 will jump to a high level after a certain delay, so that the output of the second level conversion unit 307 is a high level.

[0091] It can be seen that the enable signals of the control module, the first pull-up module and the second pull-up module of this embodiment will not change at the same time, thereby reducing the risk of competition and risk. It can also ensure that at any time there is a pull-up module in the enabled state, avoiding the situation where the output end of the power amplifier circuit is unstable.

[0092] Optionally, refer to Fig.12 The power supply terminal of the first level conversion unit 303 is electrically connected to the first first power supply input terminal VPP, and the ground terminal is electrically connected to the output terminal VPWM of the output stage switch network. The power supply terminal of the second level conversion unit 307 is electrically connected to a second first power supply input terminal VDD, and the ground terminal is electrically connected to the third power supply input terminal VCP.

[0093] Optionally, continue to refer to Figure 5 , Figure 8 and Fig.10 The filter module 13 includes a filter inductor 132 and a filter resistor 131. The filter inductor 132 and the filter resistor 131 are connected to form a low-pass filter. Of course, the filter module 13 can also be a low-pass filter of other circuit types.

[0094] For example, Fig.14 A timing diagram of a power amplifier circuit provided by an embodiment of the present invention, comprising Fig.14 It can be obtained that before time t0, the second pull-up module is enabled, and the output voltage of the output terminal Vout of the power amplifier circuit is less than the voltage of the second first power input terminal VDD, and there is a small loss at this time. After time t0, the first pull-up module is enabled, and the output voltage of the output terminal Vout of the power amplifier circuit is greater than the voltage of the second first power input terminal VDD and less than the voltage of the first first power input terminal VPP, ensuring that the power amplifier circuit can amplify the signal to be amplified to the target strength.

[0095] The present invention also provides a control method for a power amplifier circuit, which is used to control the power amplifier circuit provided by any embodiment of the present invention. Fig.15 As shown, Fig.15 A flow chart of a control method for a power amplifier circuit provided by an embodiment of the present invention, the control method comprising:

[0096] Step S501, obtaining a target strength of an output signal of a power amplifier circuit;

[0097] Specifically, the target intensity is, for example, a target amplitude at the next moment, which can be obtained by prediction. The specific prediction method is well known to those skilled in the art and will not be described in detail here.

[0098] Step S502: enabling an enable terminal of a preset pull-up module according to a target strength.

[0099] Specifically, after obtaining the target strength, the pull-up module corresponding to the working voltage that is greater than the target strength of the output signal and closest to the target strength may be selected and enabled, thereby ensuring that the signal to be amplified can be amplified normally with less loss.

[0100] The control method provided by the embodiment of the present invention enables the power amplifier circuit to amplify the signal to be amplified normally while having a smaller loss.

[0101] It should be understood that the various forms of processes shown above can be used to reorder, add or delete steps. For example, the steps described in the present invention can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of the present invention can be achieved, and this document does not limit this.

[0102] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A power amplifier circuit, characterized in that: The power amplifier circuit includes an output stage switch network; the output stage switch network includes at least two pull-up modules; The pull-up module comprises a first power input terminal, a first signal input terminal, an enable terminal and a first output terminal; the pull-up module is configured to turn on or off the first power input terminal and the first output terminal according to a signal of the first signal input terminal when the enable terminal is enabled; The first output ends of different pull-up modules are electrically connected, and the voltages input to at least two of the first power input ends are different.

2. The power amplifier circuit according to claim 1, characterized in that: The at least two pull-up modules include a first pull-up module and at least one second pull-up module; the voltage input to the first power input terminal corresponding to the first pull-up module is greater than the voltage input to the first power input terminal corresponding to the second pull-up module; The second pull-up module includes an anti-backflow unit, and the anti-backflow unit is used to prevent a first power input terminal corresponding to the first pull-up module from being short-circuited with a first power input terminal corresponding to the second pull-up module.

3. The power amplifier circuit according to claim 2, characterized in that: The first pull-up module comprises a first switch unit, a first end of the first switch unit is electrically connected to a first power input end of the first pull-up module, and a second end of the first switch unit is electrically connected to a first output end of the first pull-up module; The second pull-up module further includes a second switch unit; the second switch unit and the backflow prevention unit are connected in series between the first power input terminal of the second pull-up module and the first output terminal of the second pull-up module.

4. The power amplifier circuit according to claim 3, characterized in that: The backflow prevention unit includes a third switch unit; a control end of the third switch unit is electrically connected to an enable end of the second pull-up module; and a control end of the second switch unit is electrically connected to a signal input end of the second pull-up module.

5. The power amplifier circuit according to claim 3, characterized in that: The anti-backflow unit includes a unidirectional conduction unit, and the unidirectional conduction unit and the second switch unit are connected in series between the first power input end of the second pull-up module and the first output end of the second pull-up module; The second pull-up module also includes a first logic unit, a first input end of the first logic unit is electrically connected to the enable end of the second pull-up module, a second input end of the first logic unit is electrically connected to the signal input end of the second pull-up module, and an output end of the first logic unit is electrically connected to the control end of the second switch unit; the first logic unit is configured to output the signal of its second input end to its output end when its first input end is enabled.

6. The power amplifier circuit according to claim 3, characterized in that: The first pull-up module also includes a second logic unit, a first input end of the second logic unit is electrically connected to the enable end of the first pull-up module, a second input end of the second logic unit is electrically connected to the signal input end of the first pull-up module, and an output end of the second logic unit is electrically connected to the control end of the first switch unit; the second logic unit is configured to output the signal of its second input end to its output end when its first input end is enabled.

7. The power amplifier circuit according to claim 1, characterized in that: The power amplifier circuit further includes a control module, the control module including a control terminal and at least two enable output terminals electrically connected to the enable terminals of the at least two pull-up modules in a one-to-one correspondence; The control module is configured to output an enable signal from the enable output terminal according to a control signal from the control terminal.

8. The power amplifier circuit according to claim 7, characterized in that: The at least two pull-up modules include a first pull-up module and a second pull-up module; the control module includes: a first rising edge delay unit, a first logic AND unit, a first level conversion unit, an inverter unit, a second rising edge delay unit, a second logic AND unit and a second level conversion unit; The first end of the first rising edge delay unit is electrically connected to the control end of the control module, the second end of the first rising edge delay unit is electrically connected to the first input end of the first logic and unit; the second input end of the first logic and unit is electrically connected to the control end of the control module, the output end of the first logic and unit is electrically connected to the input end of the first level conversion unit; the output end of the first level conversion unit is electrically connected to the enable end corresponding to the first pull-up module; The input end of the inverter unit is electrically connected to the control end of the control module, the first end of the second rising edge delay unit is electrically connected to the output end of the inverter unit, the second end of the second rising edge delay unit is electrically connected to the first input end of the second logic AND unit; the second input end of the second logic AND unit is electrically connected to the output end of the inverter unit, the output end of the second logic AND unit is electrically connected to the input end of the second level conversion unit; the output end of the second level conversion unit is electrically connected to the enable end corresponding to the second pull-up module.

9. The power amplifier circuit according to claim 1, characterized in that: The output stage switch network further includes at least two pull-down modules corresponding one-to-one to the at least two pull-up modules; The pull-down module comprises a second power input terminal, a second signal input terminal and a second output terminal; the pull-down module is configured to connect or disconnect the second power input terminal and the second output terminal according to a signal of the second signal input terminal; Wherein, the second output end of the pull-down module is electrically connected to the first output end of the pull-up module; And / or, the power amplifier circuit further includes a filtering module, a triangular wave generating module and a comparing module; The first input end of the comparison module is electrically connected to the triangle wave generation module, the second input end of the comparison module is used to access the signal to be amplified, and the output end of the comparison module is electrically connected to the first signal input end of the pull-up module; The input end of the filter module is electrically connected to the first output end of the pull-up module, and the output end of the filter module is electrically connected to the output end of the power amplifier circuit.

10. A control method for a power amplifier circuit, applied to the power amplifier circuit according to any one of claims 1 to 9, characterized in that: The control method of the power amplifier circuit comprises: Obtaining a target strength of an output signal of a power amplifier circuit; An enable terminal of a preset pull-up module is enabled according to the target strength.

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