Power amplifier, chip, radio frequency front-end module and transformer structure

Abstract

The application discloses a power amplifier, a chip, a radio frequency front-end module and a transformer structure, wherein the power amplifier comprises a first power amplification circuit, a second power amplification circuit and a balun, and the first power amplification circuit and the second power amplification circuit are connected with the balun respectively; the balun comprises a primary coupling line, the primary coupling line comprising a first input end and a second input end; a secondary coupling line, the secondary coupling line comprising a first output end and a second output end; wherein a first wire path of the primary coupling line follows a second wire path of the secondary coupling line, the first wire path being a wire path from the first input end to the second input end, and the second wire path being a wire path from the first output end to the second output end. The balun in the power amplifier of the application has better coupling degree due to the fact that the primary coupling line and the secondary coupling line follow each other, and the shape and position of the primary coupling line and the secondary coupling line can be flexibly adjusted, thereby facilitating the miniaturization design of the radio frequency front-end module.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of radio frequency technology, and in particular to a power amplifier, a chip, a radio frequency front-end module and a transformer structure. BACKGROUND

[0002] Radio frequency power amplifiers are widely used in the fields of communication, broadcasting, radar, industrial processing, medical instruments and scientific research. At present, with the development of 5G communication systems, higher requirements are put forward for radio frequency power amplifiers, such as meeting higher frequencies and higher order QAM modulation.

[0003] In a radio frequency power amplifier, impedance matching is a very important part, and a transformer is usually used to match the input or output impedance of the radio frequency power amplifier. However, the traditional transformer structure usually occupies a large area, which is not conducive to the miniaturization design of the radio frequency front-end module. SUMMARY

[0004] The present application provides a power amplifier, a chip, a radio frequency front-end module and a transformer structure, which can reduce the area occupied by the power amplifier and is conducive to the miniaturization design of the radio frequency front-end module.

[0005] In a first aspect, an embodiment of the present application provides a power amplifier, comprising a first power amplification circuit, a second power amplification circuit and a balun, the first power amplification circuit and the second power amplification circuit are connected with the balun respectively; the balun comprises: a primary coupling line, the primary coupling line comprises a first input end and a second input end; a secondary coupling line, the secondary coupling line comprises a first output end and a second output end; wherein a first trace path of the primary coupling line follows a second trace path of the secondary coupling line, the first trace path is a trace path from the first input end to the second input end, and the second trace path is a trace path from the first output end to the second output end.

[0006] In a second aspect, an embodiment of the present application provides a chip, comprising at least one power amplifier, the power amplifier comprises a first power amplification circuit, a second power amplification circuit and a balun, the first power amplification circuit and the second power amplification circuit are connected with the balun respectively; the balun comprises: a primary coupling line, the primary coupling line comprises a first input end and a second input end; a secondary coupling line, the secondary coupling line comprises a first output end and a second output end; wherein a first trace path of the primary coupling line follows a second trace path of the secondary coupling line, the first trace path is a trace path from the first input end to the second input end, and the second trace path is a trace path from the first output end to the second output end.

[0007] In a third aspect, the embodiments of the present application provide a radio frequency front-end module, comprising: a substrate; a power amplifier chip disposed on the substrate; and a balun disposed on the substrate and connected with the power amplifier chip, the balun comprising: a primary coupling line comprising a first input end and a second input end; and a secondary coupling line comprising a first output end and a second output end; wherein a first trace path of the primary coupling line follows a second trace path of the secondary coupling line, the first trace path being a trace path from the first input end to the second input end, and the second trace path being a trace path from the first output end to the second output end.

[0008] In a third aspect, the embodiments of the present application provide a transformer structure, comprising: a primary coupling line comprising a first input end and a second input end; and a secondary coupling line comprising a first output end and a second output end; wherein a first trace path of the primary coupling line follows a second trace path of the secondary coupling line, the first trace path being a trace path from the first input end to the second input end, and the second trace path being a trace path from the first output end to the second output end.

[0009] In the embodiments of the present application, since the primary coupling line 201 and the secondary coupling line 202 of the balun / transformer structure follow each other from the starting point to the ending point, each segment of the primary coupling line can be coupled with the corresponding segment of the secondary coupling line, and vice versa, so that the coupling degree is better. Moreover, the shape and layout position of the primary coupling line 201 and the secondary coupling line 202 of the transformer structure / balun can be flexibly set to adapt to the layout of other circuits in the power amplifier, so that the overall structure of the power amplifier is more compact, thereby reducing the area occupied by the power amplifier and facilitating the miniaturization design of the radio frequency front-end module. BRIEF DESCRIPTION OF DRAWINGS

[0010] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative effort.

[0011] Figure 1 A schematic diagram of a transformer structure provided by the related art is shown.

[0012] Figure 2 A schematic diagram of a transformer structure provided by an embodiment of the present application is shown.

[0013] Figure 3A schematic diagram of a transformer structure is shown.

[0014] Figure 4 A schematic diagram of a transformer structure is shown.

[0015] Figure 5 A schematic diagram of a transformer structure is shown.

[0016] Figure 6 A schematic diagram of a transformer structure is shown.

[0017] Figure 7 A schematic diagram of a power amplifier is shown.

[0018] Figure 8 A schematic diagram of a power amplifier is shown.

[0019] Figure 9 A schematic diagram of a power amplifier is shown.

[0020] Figure 10 A schematic diagram of a power amplifier is shown.

[0021] Figure 11 A schematic diagram of a primary coupling line and a secondary coupling line is shown.

[0022] Figure 12 A schematic diagram of a primary coupling line and a secondary coupling line is shown.

[0023] Figure 13 A schematic diagram of a power amplifier is shown.

[0024] Figure 14 A schematic diagram of a power amplifier is shown.

[0025] Figure 15 A schematic diagram of a power amplifier is shown.

[0026] Figure 16 A schematic diagram of a power amplifier is shown.

[0027] Figure 17 A schematic diagram of a power amplifier is shown.

[0028] Figure 18 A schematic diagram of a power amplifier is shown.

[0029] Figure 19 A chip structure diagram provided by an embodiment of the present application is shown.

[0030] Figure 20 A chip structure diagram provided by another embodiment of the present application is shown.

[0031] Figure 21 A chip structure diagram provided by yet another embodiment of the present application is shown.

[0032] Figure 22 A structure diagram of a radio frequency front end module provided by an embodiment of the present application is shown. DETAILED DESCRIPTION

[0033] In order to make personnel in the art better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, but not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0034] The terms “first”, “second”, and the like in the present application are used to distinguish different objects, and are not used to describe a specific order. In addition, the terms “include” and “have” and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device including a series of steps or units is not limited to the listed steps or units, but can optionally include other steps or units not listed or can optionally include other steps or units inherent to the process, method, product or device.

[0035] In this document, reference to “an embodiment” means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the application. The appearances of the phrase in various places in the specification are not necessarily all referring to the same embodiment, nor are they necessarily mutually exclusive of one another. It is explicitly contemplated that embodiments described herein can be combined with each other.

[0036] A transformer is a device that uses electromagnetic induction to change the voltage of alternating current, usually having a primary coil and a secondary coil. In power amplifiers, transformers can also be used for impedance matching. In the related art, such as Figure 1As shown, the primary coil has two input ports in1 and in2, and the secondary coil has two output ports out1 and out2. The input ports in1 and in2 of the primary coil are usually arranged close to the pre-stage circuit, and the output ports out1 and out2 of the secondary coil are arranged close to the post-stage circuit, so as to facilitate the connection of the primary coil with the pre-stage circuit and the connection of the secondary coil with the post-stage circuit. The related art usually takes a position between the pre-stage circuit and the post-stage circuit as the center, and takes one input port or output port as the starting point and the other input port or output port as the ending point, and respectively winds the primary coil and the secondary coil, so that the overall shape of the transformer formed is a nearly closed ring. Since the internal space of the ring is insufficient to place the pre-stage circuit or the post-stage circuit, the pre-stage circuit and the post-stage circuit can only be arranged on the two sides of the transformer, and the internal space of the ring is wasted, resulting in that the power amplifier occupies a large area, which is not conducive to the miniaturization design of the radio frequency front-end module. In addition, the gap between the two input ports in1 and in2 of the primary coil cannot be coupled with the secondary coil, and the gap between the two output ports out1 and out2 of the secondary coil cannot be coupled with the primary coil, so that the coupling degree of the transformer structure is affected.

[0037] Therefore, an embodiment of the present application provides a transformer structure, a power amplifier and a radio frequency front-end module, which can reduce the area occupied by the power amplifier and facilitate the miniaturization design of the radio frequency front-end module.

[0038] Please refer to Figure 2 , Figure 2 A transformer structure provided by an embodiment of the present application is shown. As shown in Figure 2 , the transformer structure 20 includes a primary coupling line 201 and a secondary coupling line 202. The primary coupling line 201 includes a first input end In1 and a second input end In2, and the secondary coupling line 202 includes a first output end Out1 and a second output end Out2. The primary coupling line 201 is an input stage of the transformer structure 20, and is used to receive a radio frequency input signal from a pre-stage circuit. The secondary coupling line 202 is an output stage of the transformer structure 20, and is used to be coupled with the primary coupling line 201 to generate a radio frequency signal, and output the generated radio frequency signal to a post-stage circuit.

[0039] In the embodiments of the present application, the routing path of the primary coupling line 201 from the first input end In1 to the second input end In2 is referred to as a first routing path, and the routing path of the secondary coupling line 202 from the first output end Out1 to the second output end Out2 is referred to as a second routing path, wherein the first routing path follows the second routing path. In other words, if the first input end In1 is taken as the starting point of the primary coupling line 201, the second input end In2 is taken as the ending point of the primary coupling line 201, the first output end Out1 is taken as the starting point of the secondary coupling line 202, and the second output end Out2 is taken as the ending point of the secondary coupling line 202, the primary coupling line 201 and the secondary coupling line 202 each have a substantially same shape and a substantially same trend from the starting point to the ending point.

[0040] In the embodiments of the present application, "follows" means that each segment of the primary coupling line is substantially parallel to the corresponding segment of the secondary coupling line. For example, if the primary coupling line 201 and the secondary coupling line 202 are both straight or arc-shaped, the primary coupling line and the secondary coupling line are parallel to each other as a whole. If the primary coupling line 201 and the secondary coupling line 202 each include one or more bends, the primary coupling line 201 and the secondary coupling line 202 can be divided into multiple segments by taking each bend point as a boundary, and each segment of the primary coupling line 201 is substantially parallel to the corresponding segment of the secondary coupling line 202.

[0041] Since the paths of the primary coupling line 201 and the secondary coupling line 202 from the starting point to the ending point follow each other, each segment of the primary coupling line can be coupled with the corresponding segment of the secondary coupling line, and vice versa. Compared with the structure shown in FIG. 1, the structure shown in FIG. 2 has a better coupling degree. Figure 1

[0042] On the other hand, since the primary coupling line 201 and the secondary coupling line 202 are coupled with each other, the distance therebetween is small, and they follow each other, the starting points of the primary coupling line 201 and the secondary coupling line 202 are adjacent to each other, and the ending points of the primary coupling line 201 and the secondary coupling line 202 are also adjacent to each other. In other words, the first input end In1 of the primary coupling line 201 and the first output end Out1 of the secondary coupling line 202 are arranged adjacent to each other, and the second input end In2 of the primary coupling line 201 and the second output end Out2 of the secondary coupling line 202 are arranged adjacent to each other.

[0043] Based on this, the primary coupling line 201 and the secondary coupling line 202 of the transformer structure as a whole have a line structure, and the shape and layout position thereof can be flexibly set to adapt to the layout of other circuits in the power amplifier, so that the overall structure of the power amplifier is more compact, thereby reducing the area occupied by the power amplifier and facilitating the miniaturization design of the radio frequency front-end module.

[0044] Exemplarily, as shown in FIG. 3, the primary coupling line 201 and the secondary coupling line 202 are arranged on the same plane.​Figure 3 As shown in (a), both the primary coupling line 201 and the secondary coupling line 202 are laid out in a straight line. Therefore, the overall transformer structure presents a narrow, elongated shape, eliminating any unusable enclosed space and resulting in a very small overall footprint. In this configuration, the preamplifier and power amplifier circuits can be positioned on opposite sides of the transformer structure. The distance between the preamplifier and power amplifier circuits only needs to be slightly greater than the width of the transformer structure, making the overall layout of the power amplifier and RF front-end module compact and neat.

[0045] For example, such as Figure 3 As shown in (b), both the primary coupling line 201 and the secondary coupling line 202 are arranged in a zigzag pattern. This results in a narrow, strip-shaped structure with one or more bends, allowing for flexible bending to accommodate the relative positions of the preceding and following circuits, thus making the layout of the preceding, following, and transformer structures more compact. The bending pattern of the primary coupling line 201 and the secondary coupling line 202 can be designed according to the layout requirements of the preceding and following circuits. For example, when a gap is required between the preceding and following circuits, the primary coupling line 201 and the secondary coupling line 202 can be bent as follows: Figure 3 As shown in (b), the primary coupling line 201 and the secondary coupling line 202 are interspersed between the pre-amplifier circuit and the post-amplifier circuit to make the overall layout more compact. When the pre-amplifier circuit and the post-amplifier circuit need to be placed close together, the primary coupling line 201 and the secondary coupling line 202 can be bent in other ways, such as by wrapping around / semi-wrapping around the pre-amplifier circuit and / or the post-amplifier circuit, so that the pre-amplifier circuit and the post-amplifier circuit can be close together, and the space inside the bend of the transformer structure can be utilized, thereby making the layout of the power amplifier and the RF front-end module more compact and occupying less area.

[0046] For example, such as Figure 4 As shown, both the primary coupling line 201 and the secondary coupling line 202 are roughly L-shaped. The transformer structure as a whole is L-shaped. The inner side of the bend of the L-shaped structure can be used to lay out at least some circuit elements in the pre-stage circuit and / or the post-stage circuit. That is, the transformer structure can be set to semi-encircle the pre-stage circuit or the post-stage circuit or both, so as to utilize the space at the bend of the L-shaped structure, thereby making the layout of the power amplifier and the RF front-end module more compact and occupying less area.

[0047] Optionally, when a relatively wide gap is required between the preceding stage circuit and the following stage circuit, it can be as follows: Figure 4 As shown in (a), one of the front-end circuit and the other of the rear-end circuit are positioned inside the bend of the L-shaped structure, and the other is positioned outside the bend of the L-shaped transformer structure. When the front-end circuit and the rear-end circuit need to be positioned close together, they can be arranged as follows: Figure 4As shown in (b), both are placed inside the bend of the L-shaped transformer structure so that the front-end circuit and the back-end circuit can be close together, and the space inside the L-shaped bend can be utilized, thereby making the layout of the power amplifier and the RF front-end module more compact and occupying less area.

[0048] For example, such as Figure 5 As shown, both the primary coupling line 201 and the secondary coupling line 202 are arranged in a U-shape, and the overall transformer structure is U-shaped. The inner side of the U-shaped structure can be used to arrange at least some circuit elements in the front-end circuit and / or the back-end circuit, so that the space inside the U-shaped structure can be used reasonably, thereby making the layout of the power amplifier and the RF front-end module more compact and occupying less area.

[0049] Optionally, when a relatively wide gap is required between the preceding and following stage circuits, one of the preceding and following stage circuits can be placed inside the U-shaped transformer structure, and the other outside the U-shaped structure. When the preceding and following stage circuits need to be placed close together, they can be arranged as follows: Figure 5 As shown in (a) or (b), both are placed inside the U-shaped transformer structure so that the front-end circuit and the back-end circuit can be close together, and the space inside the U-shaped structure can be utilized, thereby making the layout of the power amplifier and RF front-end module more compact and occupying less area.

[0050] In one implementation, in the above-described straight, broken-line, L-shaped, or U-shaped examples, the length of the primary coupling line 201 is equal to the length of the secondary coupling line 202 to increase the coupling area between the primary coupling line 201 and the secondary coupling line 202, thereby improving the coupling degree of the transformer structure. Specifically, for broken-line, L-shaped, or U-shaped transformer structures, the length of the primary coupling line 201 and the secondary coupling line 202 can be made equal by adjusting the position of the bend. Taking an L-shaped transformer structure as an example, the primary coupling line 201 and the secondary coupling line 202 of the L-shaped transformer structure each consist of two line segments connected at a second angle. By changing the inner and outer positional relationship of the primary coupling line 201 and the secondary coupling line 202 at the bend, such that one segment of the primary coupling line 201 is outside the secondary coupling line 202 and the other segment is inside the secondary coupling line 202, the lengths of the primary coupling line 201 and the secondary coupling line 202 can be made equal or approximately equal. The U-shaped transformer structure or other zigzag transformer structures are similar. By changing the internal and external positional relationship between the primary coupling line 201 and the secondary coupling line 202 at at least one bend, the length of the primary coupling line 201 and the length of the secondary coupling line 202 can be made equal. Specific details will not be elaborated here.

[0051] It should be understood that, for the transformer structure of the zigzag shape, the L shape or the U shape, in order to avoid the sudden change of the current direction on the primary coupling line and the secondary coupling line, the bending part of the primary coupling line and the secondary coupling line of the zigzag shape or the L shape can also be designed as a circular arc shape, so that the current direction change is buffered, the loss of the radio frequency signal is reduced, and the radio frequency signal transmission efficiency is improved.

[0052] Exemplarily, as shown in Figure 6 The primary coupling line 201 and the secondary coupling line 202 are both arranged in an arc shape. Since the primary coupling line 201 and the secondary coupling line 202 follow each other and both are not closed arc shapes, the transformer structure formed thereby also presents an open arc structure, and at least part of the circuit elements in the pre-stage circuit or the post-stage circuit can be arranged on the inner side of the arc structure, so that the space on the inner side of the arc is effectively utilized, the area waste is reduced, the layout of the power amplifier and the radio frequency front-end module is more compact, and the occupied area is smaller. Moreover, the current direction change in the arc coupling line is relatively slow, which can reduce the loss of the radio frequency signal and improve the radio frequency signal transmission efficiency.

[0053] Optionally, the central angle of the arc formed by the primary coupling line 201 and the secondary coupling line 202 is less than or equal to 270°, that is, the arc formed by the primary coupling line 201 and the secondary coupling line 202 is less than or equal to 3 / 4 of a circle, so that the arc of the transformer structure presents an opening greater than or equal to 1 / 4 of a circle, thereby facilitating the layout of at least part of the circuit elements of the pre-stage circuit or the post-stage circuit on the inner side of the arc structure.

[0054] Optionally, the central angle of the arc formed by the primary coupling line 201 and the secondary coupling line 202 is less than or equal to 180°, that is, the arc formed by the primary coupling line 201 and the secondary coupling line 202 is less than or equal to a semicircle, so that the arc of the transformer structure presents an opening greater than or equal to a semicircle, thereby facilitating the layout of more circuit elements on the inner side of the arc structure.

[0055] Optionally, the central angle of the arc formed by the primary coupling line 201 and the secondary coupling line 202 is greater than or equal to 90°, that is, the arc formed by the primary coupling line 201 and the secondary coupling line 202 is greater than or equal to 1 / 4 of a circle, so that the primary coupling line 201 and the secondary coupling line 202 have a certain length, thereby meeting the inductance required for impedance matching.

[0056] As an implementation, when the primary coupling line 201 and the secondary coupling line 202 adopt an arc structure, the radius and the central angle of the arc structure can be determined according to the circuit area of the front-stage circuit or the back-stage circuit and the inductance required for impedance matching. The radius of the arc structure can be positively correlated with the inductance required for impedance matching and the circuit area required to be arranged inside the arc structure. Thus, under the same central angle, the greater the radius, the greater the space inside the arc structure, the more circuit elements can be laid out, and the longer the wire, the greater the inductance can be provided. In addition, the central angle of the arc structure can be negatively correlated with the circuit area required to be arranged inside the arc structure, that is, the greater the circuit area required to be laid out inside, the smaller the central angle of the arc structure, and the greater the opening, to facilitate the layout of the circuit elements.

[0057] In the above examples, the front-stage circuit refers to the circuit connected to the primary coupling line 201, and the output signal of the front-stage circuit is the input signal of the transformer structure. The back-stage circuit refers to the circuit connected to the secondary coupling line 202, and the signal output by the secondary coupling line 202 is the input signal of the back-stage circuit.

[0058] For example, the primary coupling line 201 of the transformer structure can be used to receive a radio frequency signal to be amplified, and the secondary coupling line 202 can be used to connect the input end of the power amplification circuit, so that the radio frequency signal to be amplified is input impedance matched by the transformer structure and then power amplified by the power amplification circuit.

[0059] For example, when the transformer structure is used as an inter-stage impedance matching circuit in a multi-stage power amplifier, the front-stage circuit and the back-stage circuit of the transformer structure can be power amplification circuits of different stages in the multi-stage power amplifier. Taking a two-stage power amplifier as an example, the primary coupling line 201 of the transformer structure can be used to connect the output end of the first-stage power amplifier to receive the radio frequency signal output by the first-stage power amplification circuit, and the secondary coupling line 202 can be used to connect the input end of the second-stage power amplification circuit to input the radio frequency signal that has been impedance matched to the second-stage power amplification circuit for second-stage power amplification.

[0060] For example, when the transformer structure is used as an output impedance matching circuit in a power amplifier, the front-stage circuit of the transformer structure can include a power amplification circuit. The primary coupling line 201 of the transformer structure can be used to receive the radio frequency signal of the power amplification circuit, and the secondary coupling line 202 can output the radio frequency signal that has been impedance matched to other modules in the radio frequency front-end module, such as a radio frequency switch module.

[0061] It should be understood that in some radio frequency front-end modules, multiple impedance matching circuits are provided simultaneously, and the transformer structure can be applied to one or more impedance matching circuits in the radio frequency front-end module. When multiple impedance matching circuits all adopt the transformer structure described above, for some transformer structures, the power amplification circuit is the front-stage circuit, and for some other transformer structures, the power amplification circuit is the back-stage circuit.

[0062] In the embodiments of the present application, the transformer structure can be integrated in a chip or provided on a substrate, and the specific arrangement can be determined according to application requirements. For example, the substrate can provide a larger wiring space than the chip, thereby achieving a larger inductance. Therefore, when the primary coupling line and the secondary coupling line of the transformer need to have a larger inductance, the transformer structure can be provided on the substrate; when the inductance requirement of the primary coupling line and the secondary coupling line is relatively low, the transformer structure can be integrated in the chip, and can be specifically integrated in the chip where the power amplifier is located. For another example, when the transformer structure is used as an inter-stage impedance matching circuit of the power amplifier, the transformer structure needs to be connected to multiple power amplification circuits of the power amplifier respectively, and the inductance requirement of the primary coupling line and the secondary coupling line is not high, so the transformer structure can be integrated in the chip where the power amplifier is located, so as to facilitate circuit connection.

[0063] In the embodiments of the present application, since the primary coupling line and the secondary coupling line are arranged following each other, the length of each coupling line is substantially the same, and 1 primary coupling line and 1 secondary coupling line can achieve an inductance ratio of about 1:1. In some application scenarios, if an inductance ratio different from 1:1 is required, the number of the primary coupling line 201 and / or the secondary coupling line 202 can be set to multiple, and the inductance ratio different from 1:1 can be achieved by series connection between multiple primary coupling lines and / or series connection between multiple secondary coupling lines. For example, when an inductance ratio of 2:1 is required, 2 primary coupling lines and 1 secondary coupling line can be provided, and the 2 primary coupling lines are connected in series to have an inductance about twice that of the secondary coupling line, thereby achieving an inductance ratio of 2:1. At this time, in order to improve the coupling degree between the primary coupling line and the secondary coupling line, the secondary coupling line can be arranged between the 2 primary coupling lines, so that the secondary coupling line can be coupled with both of the 2 primary coupling lines, thereby improving the coupling degree of the transformer structure. Similarly, when an inductance ratio of 1:2 is required, 1 primary coupling line and 2 secondary coupling lines can be provided, and the 2 secondary coupling lines are connected in series to have an inductance about twice that of the primary coupling line, thereby achieving an inductance ratio of 1:2. At this time, in order to improve the coupling degree between the primary coupling line and the secondary coupling line, the primary coupling line can be arranged between the 2 secondary coupling lines, so that both of the 2 secondary coupling lines can be well coupled with the primary coupling line.

[0064] In at least one embodiment, in order to improve the coupling degree between the primary coupling lines and the secondary coupling lines, at least one primary coupling line can be split into two parallel coupling lines, and the secondary coupling line is arranged between the two split primary coupling lines, so as to strengthen the coupling degree between the primary coupling lines and the secondary coupling lines. For example, the line width of each primary coupling line can be slightly smaller than the line width of the secondary coupling line, or remains substantially the same as the line width of the secondary coupling line, so that the coupling degree of the transformer structure is better. Alternatively, at least one secondary coupling line can be split into two parallel coupling lines, and the primary coupling line is arranged between the two split secondary coupling lines, so as to strengthen the coupling degree between the primary coupling lines and the secondary coupling lines. Optionally, the line width of each secondary coupling line after splitting can be slightly smaller than the line width of the primary coupling line, or remains substantially the same as the line width of the primary coupling line, further improving the coupling degree of the transformer structure.

[0065] In at least one embodiment, the primary coupling lines or the secondary coupling lines can also be split into more lines, and the primary coupling lines and the secondary coupling lines are arranged alternately, so as to further increase the coupling area of the primary coupling lines and the secondary coupling lines, and improve the coupling degree of the transformer structure.

[0066] Optionally, when the number of primary coupling lines and secondary coupling lines is multiple and located in the same plane, in order to ensure the balance of the primary coupling lines and the secondary coupling lines, the coupling lines on both sides can be the same type of coupling lines, for example, both sides are primary coupling lines or both sides are secondary coupling lines, then the difference between the number of primary coupling lines and the number of secondary coupling lines needs to be 1. For example, the transformer structure can include N primary coupling lines and M secondary coupling lines, and the N primary coupling lines and the M secondary coupling lines are arranged alternately; wherein N and M are positive integers, and N=M+1 or N=M-1. For example, when the number of primary coupling lines is 1 more than the number of secondary coupling lines, that is, N=M+1, the primary coupling lines and the secondary coupling lines are arranged alternately in the order of primary→secondary→…→primary; when the number of secondary coupling lines is 1 more than the number of primary coupling lines, that is, N=M-1, the primary coupling lines and the secondary coupling lines are arranged alternately in the order of secondary→primary→…→secondary. In this way, the coupling degree of the transformer structure can be improved while ensuring the balance of the transformer structure.

[0067] According to the above embodiments, the number of the primary coupling lines 201 and the secondary coupling lines 202 can be one or more, respectively. When there are multiple primary coupling lines 201, the multiple primary coupling lines 201 can be connected in series or in parallel; when there are multiple secondary coupling lines 202, the multiple secondary coupling lines 202 can be connected in series or in parallel. The number of the primary coupling lines 201 and the secondary coupling lines 202, the connection relationship between the multiple primary coupling lines 201, and the connection relationship between the multiple secondary coupling lines 202 can be set according to the required ratio of inductance and the coupling degree.

[0068] In some embodiments, when the number of the primary coupling lines and the secondary coupling lines is one, the primary coupling line and the secondary coupling line are located in the same plane; when the number of the primary coupling lines or the secondary coupling lines is multiple, at least one primary coupling line and at least one secondary coupling line are located in the same plane. By setting at least one primary coupling line and at least one secondary coupling line in the same plane, they can be prepared in the same metal layer of a chip or a substrate, thereby reducing the number of metal layers occupied by the balun and reducing the cost. Moreover, being prepared in the same metal layer can make the thickness of the primary coupling line the same as the thickness of the secondary coupling line, and the coupling degree of the balun is better.

[0069] The embodiments of the present application also provide a power amplifier, as shown in the following table: Figure 7 As shown in the table, the power amplifier 70 can include a first power amplification circuit 701, a second power amplification circuit 702, and a balun 703, and the first power amplification circuit 701 and the second power amplification circuit 702 are connected with the balun 703. The balun 703 includes a primary coupling line 7031 and a secondary coupling line 7032, the primary coupling line 7031 includes a first input end In1 and a second input end In2, and the secondary coupling line 7032 includes a first output end Out1 and a second output end Out1.

[0070] In the embodiments of the present application, the power amplifier 70 includes at least one differential power amplification circuit, for example, the first power amplification circuit 701 and the second power amplification circuit 702 can constitute one differential power amplification circuit. Alternatively, the power amplifier 70 can be a push-pull power amplifier or a balanced power amplifier, or a combination of at least one single-ended power amplification circuit and at least one differential power amplification circuit.

[0071] Alternatively, the balun 703 is used to realize the input impedance matching or the output impedance matching of the differential power amplification circuit, and when the power amplifier is a multi-stage power amplifier, it can also be used to realize the inter-stage impedance matching of the multi-stage power amplifier.

[0072] As an implementation, the balun 703 can be used for output impedance matching of the differential power amplification circuit, and realize balanced-unbalanced conversion of the radio frequency signal, i.e., convert the balanced radio frequency signal amplified and output by the first power amplification circuit 701 and the second power amplification circuit 702 into an unbalanced radio frequency signal for output, for example, to a switch circuit at the back end of the power amplifier, and the unbalanced radio frequency signal is selectively output to an antenna port by the switch circuit.

[0073] As another implementation, the balun 703 can be used for input impedance matching or inter-stage impedance matching of the differential power amplification circuit, when the input radio frequency signal of the differential power amplification circuit is an unbalanced signal, or when a single-ended power amplification circuit is further provided at the front end of the first power amplification circuit 701 and the second power amplification circuit 702, the balun 703 is also used to realize unbalanced-balanced conversion of the radio frequency signal, i.e., convert the unbalanced radio frequency input signal into a balanced radio frequency signal, and the first power amplification circuit 701 and the second power amplification circuit 702 perform power amplification on the balanced radio frequency signal.

[0074] In the embodiments of the present application, the path of the primary coupling line 7031 from the first input end In1 to the second input end In2 is referred to as the first path, and the path of the secondary coupling line 7032 from the first output end Out1 to the second output end Out2 is referred to as the second path, wherein the first path follows the second path. In other words, if the first input end In1 is taken as the starting point of the primary coupling line 7031, the second input end In2 is taken as the terminal point of the primary coupling line 7031, the first output end Out1 is taken as the starting point of the secondary coupling line 7032, and the second output end Out2 is taken as the terminal point of the secondary coupling line 7032, the primary coupling line 7031 and the secondary coupling line 7032 each have the same path from the starting point to the terminal point, and have the same shape.

[0075] Since the paths of the primary coupling line 7031 and the secondary coupling line 7032 from the starting point to the terminal point follow each other, each segment of the primary coupling line can be coupled with the corresponding segment of the secondary coupling line, and vice versa, each segment of the secondary coupling line can be coupled with the corresponding segment of the primary coupling line. Compared with the structure shown in the prior art, the structure has better coupling degree. Figure 1

[0076] ​On the other hand, since the primary coupling line 7031 and the secondary coupling line 7032 are coupled to each other, the distance between the two is small, and they follow each other, so the starting points of the primary coupling line 7031 and the secondary coupling line 7032 are close to each other, and the ending points are also close to each other. In other words, the first input end In1 of the primary coupling line 7031 and the first output end Out1 of the secondary coupling line 7032 are arranged close to each other, and the second input end In2 of the primary coupling line 7031 and the second output end Out2 of the secondary coupling line 7032 are arranged close to each other.

[0077] Based on this, the primary coupling line 7031 and the secondary coupling line 7032 of the transformer structure as a whole present a line-shaped structure, which can be flexibly arranged in shape and layout position to adapt to the layout of other circuits in the power amplifier, make the overall structure of the power amplifier more compact, thereby reducing the area occupied by the power amplifier, and facilitating the miniaturization design of the radio frequency front-end module.

[0078] In some embodiments, the balun 703 can adopt the same structure as the transformer structure 20 of any of the foregoing embodiments, for example, the primary coupling line and the secondary coupling line can be arranged in a straight line shape, a broken line shape, an arc shape, a U shape, an L shape, etc. For details, please refer to the description of the foregoing embodiments, which will not be repeated here.

[0079] In some embodiments, as shown in Figure 8 The primary coupling line 7031 includes a first primary coupling line 7031a and a second primary coupling line 7031b, and the first primary coupling line 7031a and the second primary coupling line 7031b have first input ends In1a and In1b and second input ends In2a and In2b, respectively. The wiring path of the first primary coupling line 7031a from the first input end In1a to the second input end In2a and the wiring path of the second primary coupling line 7031b from the first input end In1b to the second input end In2b are both referred to as a first wiring path, and the first wiring path of the first primary coupling line 7031a and the second primary coupling line 7031b both follow the second wiring path of the secondary coupling line 7032. In the embodiment of the application, the secondary coupling line 7032 is arranged between the first primary coupling line 7031a and the second primary coupling line 7031b, so as to have a high coupling degree with the first primary coupling line 7031a and the second primary coupling line 7031b, and improve the coupling coefficient of the balun 703.

[0080] Optionally, the first primary coupling line 7031a and the second primary coupling line 7031b can be connected in series or in parallel. The inductance of the coupling line is mainly related to the length of the line. When two coupling lines are connected in series, the length of the coupling line is increased, and the inductance is also increased. When two coupling lines with the same length are connected in parallel, the width of the coupling line is increased, but the length of the line is unchanged, and the inductance is less affected. Therefore, in some embodiments, the ratio of the inductance of the primary and the secondary can be adjusted by increasing the number of primary / secondary coupling lines and connecting multiple primary / secondary coupling lines in series.

[0081] As an embodiment, the balun 703 is used for output impedance matching of the power amplifier. When the first primary coupling line 7031a and the second primary coupling line 7031b are connected in parallel, the input end of the balun 703 is connected to the output end of the first power amplifier circuit 701 and the second power amplifier circuit 702. Specifically, as shown in FIG. 7, the first input end In1a of the first primary coupling line 7031a and the first input end In1b of the second primary coupling line 7031b are respectively connected to the output end of the first power amplifier circuit 701, and the second input end In2a of the first primary coupling line 7031a and the second input end In2b of the second primary coupling line 7031b are respectively connected to the output end of the second power amplifier circuit 702. The first output end Out1 of the secondary coupling line 7032 is used to connect the signal transmission end 704, and the second output end Out2 of the secondary coupling line 7032 is used to ground. Figure 8

[0082] In this embodiment, the balun 703 is a balanced-unbalanced balun, which can convert the balanced (differential) signal received by the input end into an unbalanced (single-ended) signal, so as to be received by the single-ended circuit (such as a radio frequency switch) in the subsequent stage. For example, the first output end Out1 of the balun 703 can be connected to a radio frequency switch in a radio frequency front-end module, so as to transmit the amplified radio frequency signal to an antenna port connected to the radio frequency switch when the radio frequency switch is turned on, and then emit the radio frequency signal through an antenna connected to the antenna port. At this time, the balun 703 serves as an output balun of the power amplifier, which is connected between the power amplifier and the subsequent circuit, so as to match the output impedance of the power amplifier with the input impedance of the subsequent circuit, thereby reducing the loss of the radio frequency signal in the transmission process.

[0083] In this embodiment, the primary coupling line 7031 is split into two parallel coupling lines 7031a and 7031b, and the secondary coupling line 7032 is clamped between the two primary coupling lines 7031a and 7031b, so as to improve the coupling degree of the balun.

[0084] ​Since the two primary coupling lines 7031a and 7031b are connected in parallel, their impact on the inductance is relatively small. When the lengths of the two primary coupling lines 7031a and 7031b are the same as those of the secondary coupling line 7032, the ratio of the inductances between the primary and secondary windings of the balun structure is approximately 1:1. Optionally, the widths of the first and second primary coupling lines can be made slightly smaller than the width of the secondary coupling line, or kept approximately the same as the width of the secondary coupling line, to improve the coupling of the balun 703.

[0085] In one implementation, the balun 703 is used for output impedance matching of a power amplifier. When the first primary coupling line 7031a and the second primary coupling line 7031b are connected in series, the input terminal of the balun 703 is connected to the output terminals of the first power amplifier circuit 701 and the second power amplifier circuit 702. Specifically, as... Figure 9 As shown, the first input terminal In1a of the first primary coupling line 7031a is used to connect to the output terminal of the first power amplifier circuit 701, and the second input terminal In2a of the first primary coupling line 7031a is used to ground; the first input terminal In1b of the second primary coupling line 7031b is used to ground, and the second input terminal In2b of the second primary coupling line 7031b is used to connect to the output terminal of the second power amplifier circuit 702; the first output terminal Out1 of the secondary coupling line 7032 is used to connect to the signal transmission terminal, and the second output terminal Out2 of the secondary coupling line 7032 is used to ground.

[0086] In this embodiment, since the second input terminal In2a of the first primary coupling line 7031a and the first input terminal In1b of the second primary coupling line 7031b are both grounded, the first primary coupling line 7031a and the second primary coupling line 7031b are equivalent to being connected in series between the output terminal of the first power amplifier circuit 701 and the output terminal of the second power amplifier circuit 702, thereby receiving the balanced signal output by the differential power amplifier circuit including the first power amplifier circuit 701 and the second power amplifier circuit 702. One end of the secondary coupling line 703 is grounded, and the other end serves as the output, thereby converting the balanced signal received by the primary stage into an unbalanced signal for output. Similar to the aforementioned embodiments, the balun 703 can also be used to achieve impedance matching between the front-end circuit and the back-end circuit to reduce signal loss during transmission.

[0087] In this design, the first primary coupling line 7031a, the second primary coupling line 7031b, and the secondary coupling line 703 are of the same length to increase the coupling coefficient of the balun. Since the first primary coupling line 7031a and the second primary coupling line 7031b are connected in series, the length of the primary coupling line is effectively doubled, becoming twice the length of the secondary coupling line. Therefore, the balun 703 can achieve an inductance ratio of 2:1.

[0088] This embodiment splits the primary coupling line 7031 into two coupling lines 7031a and 7031b, and the secondary coupling line 7032 can be sandwiched between the two primary coupling lines 7031a and 7031b, thereby improving the coupling degree of the balun. Furthermore, by connecting the two coupling lines 7031a and 7031b in series, the inductance of the primary coupling line can be increased without increasing the length of a single coupling line, thereby adjusting the ratio of the balun inductance and meeting the needs of applications with large inductance requirements with a smaller area.

[0089] In one implementation, the balun 703 is used for input impedance or interstage impedance matching of a power amplifier. When the first primary coupling line 7031a and the second primary coupling line 7031b are connected in parallel, the output terminal of the balun 703 is connected to the input terminals of the first power amplifier circuit 701 and the second power amplifier circuit 702. Specifically, as shown... Figure 10 As shown, the first input terminal In1a of the first primary coupling line 7031a and the first input terminal In1b of the second primary coupling line 7031b are used to receive the radio frequency input signal RF-in, respectively. The second input terminal In2a of the first primary coupling coil 7031a and the second input terminal In2b of the second primary coupling line 7031b are used to ground, respectively. The first output terminal Out1 of the secondary coupling line 7032 is connected to the input terminal of the first power amplifier circuit 701, and the second output terminal Out2 of the secondary coupling line 7032 is connected to the input terminal of the second power amplifier circuit 702.

[0090] In this embodiment, the balun 703 is an unbalanced-to-balanced balun, capable of converting the unbalanced RF input signal RF-in received from the input terminal of the power amplifier or the output terminal of the preceding single-ended power amplifier circuit into a balanced RF signal, facilitating reception and processing by the subsequent differential power amplifier circuit. When the balun 703 is used as the input balun of the power amplifier, connected between the input terminals of the preceding circuit and the differential power amplifier circuit, it can convert the single-ended signal output from the preceding stage into a differential signal and match the output impedance of the preceding circuit with the input impedance of the differential power amplifier circuit, thereby reducing RF signal loss during transmission. When the balun 703 is used as an inter-stage matching balun of the power amplifier, the power amplifier includes at least one single-ended amplifier circuit and at least one differential amplifier circuit, with the single-ended amplifier circuit preceding the differential amplifier circuit. The balun 703 is connected between two adjacent single-ended amplifier circuits and differential amplifier circuits to convert the single-ended RF signal output from the previous single-ended amplifier circuit into a differential RF signal, and to match the output impedance of the previous single-ended amplifier circuit with the input impedance of the subsequent differential amplifier circuit, thereby reducing the loss of RF signal during transmission from the previous amplifier circuit to the subsequent amplifier circuit.

[0091] The embodiment can clamp the secondary coupling line 7032 between the two primary coupling lines 7031a and 7031b, thereby improving the coupling degree of the balun without affecting the ratio of the inductance of the balun.

[0092] Alternatively, the first primary coupling line 7031a, the second primary coupling line 7031b and the secondary coupling line 7032 can be provided in a straight line shape, a broken line shape, an arc shape, a U shape, an L shape, etc. according to requirements, to adapt to the layout of the first power amplification circuit 701, the second power amplification circuit 702 and other circuits.

[0093] In some embodiments, when the balun 703 has at least one bending section, if the extension directions of the first section and the last section of the balun 703 are different, the first primary coupling line, the second primary coupling line and the secondary coupling line can cross each other at the at least one bending section, so that the overall lengths of the first primary coupling line, the second primary coupling line and the secondary coupling line are substantially equal, thereby improving the coupling degree of the balun 703. The extension direction of the first section of the balun refers to the direction of extension along the coupling lines from the first input ports In1a and In1b and the first output port Out1, and the extension direction of the last section refers to the direction of extension along the coupling lines to the second input ports In2a and In2b and the second output port Out2.

[0094] Specifically, the crossing manner of the first primary coupling line, the second primary coupling line and the secondary coupling line can be that the outermost coupling line exchanges the inner-outer relationship with the outer coupling line. For example, if the first primary coupling line is outside the secondary coupling line and the second primary coupling line is inside the secondary coupling line at the first section of the bending, the inner-outer relationship of the first primary coupling line and the second primary coupling line is exchanged at the second section of the bending, and the first primary coupling line is adjusted to be inside the secondary coupling line and the second primary coupling line is adjusted to be outside the secondary coupling line.

[0095] Exemplarily, when the meander-shaped (including L-shaped) structure is adopted, the balun 703 comprises at least one bending segment, at which the first primary coupling line 7031a comprises a first line segment and a second line segment connected at a first angle, the secondary coupling line 7032 comprises a third line segment and a fourth line segment connected at a first angle, and the second primary coupling line 7031b comprises a fifth line segment and a sixth line segment connected at a first angle. Wherein, when the number of the bending segments of the balun 703 is odd, at all or part of the odd bending segments, the first line segment, the third line segment and the fifth line segment are parallel to each other and the lengths thereof are sequentially increased; and the second line segment, the fourth line segment and the sixth line segment are parallel to each other and the lengths thereof are sequentially decreased. In this way, the sum of the first line segment and the second line segment, the sum of the third line segment and the fourth line segment, and the sum of the fifth line segment and the sixth line segment can be equal or approximately equal, so that the lengths of the first primary coupling line 7031a, the second primary coupling line 7031b and the secondary coupling line 7032 are equal or approximately equal, thereby increasing the coupling area of the first primary coupling line 7031a, the second primary coupling line 7031b and the secondary coupling line 7032 and improving the coupling degree of the balun.

[0096] Exemplarily, as shown in Figure 11 the lengths of the first line segment, the second line segment, the third line segment, the fourth line segment, the fifth line segment and the sixth line segment are respectively denoted as S1, S2, S3, S4, S5 and S6, the difference between the length of the third line segment and the length of the first line segment (S3-S1), the difference between the length of the fifth line segment and the length of the third line segment (S5-S3), the difference between the length of the second line segment and the length of the fourth line segment (S2-S4), and the difference between the length of the fourth line segment and the length of the sixth line segment (S4-S6) are equal and are all a first value d, i.e. S3-S1=S5-S3=S2-S4=S4-S6=d1, then S1+S2=S3+S4=S5+S6, in this way, the lengths of the first primary coupling line 7031a, the second primary coupling line 7031b and the secondary coupling line 7032 are equal, thereby maximizing the coupling degree of the balun.

[0097] Optionally, the first angle is greater than or equal to 90°, so that the direction of the current flowing through each coupling line does not change sharply at the bending segment, thereby reducing the loss of the radio frequency signal and improving the transmission efficiency of the radio frequency signal. When the first angle is 90°, the gap between the third line segment and the first line segment and the gap between the fourth line segment and the second line segment are equal, and the lengths of the first primary coupling line 7031a, the second primary coupling line 7031b and the secondary coupling line 7032 are equal, thereby maximizing the coupling degree and the impedance matching effect of the balun.

[0098] In some embodiments, as Figure 12As shown, when the balun 703 has at least two bending sections, if the first section and the last section of the balun 703 have the same extension direction, the first primary coupling line, the second primary coupling line and the secondary coupling line can keep parallel without crossing at each bending section of the balun 703, and the lengths of the coupling lines in the balun 703 are still equal or approximately equal, and the balun 703 still has a high coupling degree.

[0099] In some embodiments, the secondary coupling line 7032 of the balun 703 includes a first secondary coupling line 7032a and a second secondary coupling line 7032b, each of the first secondary coupling line 7032a and the second secondary coupling line 7032b has a first output end and a second output end, the wiring path of the first secondary coupling line 7032a from the first output end to the second output end and the wiring path of the second secondary coupling line 7032b from the first output end to the second output end are both referred to as a second wiring path, and the first wiring path of the primary coupling line 7031 and the second wiring path of the first secondary coupling line 7032a and the second secondary coupling line 7032b follow each other.

[0100] In the embodiments of the present application, the primary coupling line 7031 is arranged between the first secondary coupling line 7032a and the second secondary coupling line 7032b, so that the first secondary coupling line 7032a and the second secondary coupling line 7032b can be coupled with the primary coupling line 7031, thereby improving the coupling degree of the balun 703.

[0101] Optionally, the first secondary coupling line 7032a and the second secondary coupling line 7032b can be connected in series or in parallel.

[0102] As an implementation, the balun 703 is used as an output balun of a power amplifier, for output impedance matching of the power amplifier, and the first secondary coupling line 7032a and the second secondary coupling line 7032b can be connected in parallel. As shown, Figure 13 As shown, the first input end In1 of the primary coupling line 7031 is connected with the output end of the first power amplification circuit 701, and the second input end In2 of the primary coupling line 7031 is connected with the output end of the second power amplification circuit 702; the first output end Out1a of the first secondary coupling line 7032a and the first output end Out1b of the second secondary coupling line 7032b are both used for connecting the signal transmission end 704, and the second output end Out2a of the first secondary coupling line 7032a and the second output end Out2b of the second secondary coupling line 7032b are both used for grounding. The balun 703 of the present embodiment is a balanced-unbalanced balun, which can convert the input differential radio frequency signal into a single-ended radio frequency signal output, and realize impedance matching between the output ends of the power amplifier (i.e. the output end of the first power amplification circuit 701 and the output end of the second power amplification circuit 702) and the input ends of the subsequent circuit.

[0103] To maximize the coupling between the primary and secondary coupling lines, the lengths of the first secondary coupling line 7032a, the second secondary coupling line 7032b, and the primary coupling line 7031 can be made the same. In this case, since the first secondary coupling line 7032a and the second secondary coupling line 7032b are connected in parallel, their impact on the inductance is relatively small. Therefore, the ratio of the inductance between the primary and secondary windings of the balun 703 is approximately 1:1.

[0104] Optionally, the width of the first-stage coupling line 7032a and the width of the second-stage coupling line 7032b can be set to be slightly smaller than the width of the primary coupling line 7031, or kept to be approximately the same as the line width of the primary coupling line 7031, so as to improve the coupling of the balun 703.

[0105] In one implementation, the balun 703 is used for input impedance matching or inter-stage impedance matching of a power amplifier. When the first-stage coupling line 7032a and the second-stage coupling line 7032b are connected in parallel, such as... Figure 14 As shown, the first input terminal In1 of the primary coupling line 7031 is used to receive the input radio frequency signal RF_in, and the first input terminal In2 of the primary coupling line 7031 is used for grounding. The first output terminal Out1a of the first primary coupling line 7032a and the first output terminal Out1b of the second primary coupling line 7032b are both connected to the input terminal of the first power amplifier circuit 701, and the second output terminal Out2a of the first primary coupling line 7032a and the second output terminal Out2b of the second primary coupling line 7032b are both connected to the input terminal of the second power amplifier circuit 702.

[0106] In this embodiment, the balun 703 is an unbalanced-balanced balun, which can convert the input single-ended RF signal into a differential RF signal and output the differential RF signal to a differential power amplifier circuit including a first power amplifier circuit and a second power amplifier circuit for power amplification. The balun 703 can also achieve impedance matching between the output terminal of the preamplifier circuit and the input terminal of the differential power amplifier circuit (i.e., the input terminal of the first power amplifier circuit 701 and the input terminal of the second power amplifier circuit 702).

[0107] To maximize the coupling between the primary and secondary coupling lines, the lengths of the first secondary coupling line 7032a, the second secondary coupling line 7032b, and the primary coupling line 7031 can be made the same. In this case, the ratio of the inductance between the primary and secondary sides of the balun 703 is approximately 1:1.

[0108] Optionally, the width of the first secondary coupling line 7032a and the width of the second secondary coupling line 7032b can be set slightly smaller than the width of the primary coupling line 7031 or remain substantially the same as the line width of the primary coupling line 7031, which can further improve the coupling degree of the balun 703.

[0109] As an implementation, the balun 703 is used for input impedance matching or inter-stage impedance matching of a power amplifier. When the first secondary coupling line 7032a and the second secondary coupling line 7032b are connected in series, as shown in FIG. 7B, the first input end In1 of the primary coupling line 7031 is used to receive an input radio frequency signal RF_in, and the first input end In2 of the primary coupling line 7031 is used for grounding. The first output end Out1a of the first secondary coupling line 7032a is connected to the input end of the first power amplifier circuit 701, and the first output end Out1b of the second secondary coupling line 7032b is connected to the input end of the second power amplifier circuit 702. In this implementation, the balun 703 is an unbalanced-balanced balun, and its function can refer to the foregoing embodiments, which will not be described here. Figure 15

[0110] Similarly, in order to maximize the coupling degree between the primary coupling line and the secondary coupling line, the first secondary coupling line 7032a and the second secondary coupling line 7032b can be made to have the same length as the primary coupling line 7031. Since the two secondary coupling lines are connected in series, the length of the secondary coupling line is increased, and the inductance of the secondary coupling line is approximately doubled, so that an inductance ratio of approximately 1:2 can be achieved.

[0111] Optionally, in the above embodiments, the first secondary coupling line 7032a, the second secondary coupling line 7032b, and the primary coupling line 7031 can be set to be straight, zigzag, arc-shaped, U-shaped, L-shaped, etc. according to the layout of the first power amplifier circuit 701, the second power amplifier circuit 702, and other circuits.

[0112] In some embodiments, when the balun 703 has at least one bending segment, if the extension directions of the first segment and the last segment of the balun 703 are different, the first secondary coupling line 7032a, the second secondary coupling line 7032b, and the primary coupling line 7031 can cross each other at the at least one bending segment, so that the overall lengths of the first secondary coupling line 7032a, the second secondary coupling line 7032b, and the primary coupling line 7031 are substantially equal, thereby improving the coupling degree of the balun 703. The extension direction of the first segment of the balun refers to the extension direction along the coupling lines from the first input port In1 and the first output port Out1a, Out1b, and the extension direction of the last segment refers to the extension direction along the coupling lines to the second input port In2 and the second output port Out2a, Out2b. ​

[0113] Specifically, the crossing method of the first-level coupling line 7032a, the second-level coupling line 7032b, and the primary coupling line 7031 can be such that the inner and outer relationships of the outermost coupling line are exchanged. For example, if in the first segment at the bend, the first-level coupling line is outside the primary coupling line and the second-level coupling line is inside the primary coupling line, then in the second segment at the bend, the inner and outer relationships of the first-level and second-level coupling lines are reversed, adjusted so that the first-level coupling line is inside the primary coupling line and the second-level coupling line is outside the primary coupling line.

[0114] For example, when a polygonal (including L-shaped) structure is adopted, the balun 703 includes at least one bend segment. At this bend segment, the first-level coupling line 7032a includes a seventh and eighth segment connected at a second angle, the primary coupling line 7031 includes a ninth and tenth segment connected at a second angle, and the second-level coupling line 7032b includes an eleventh and twelfth segment connected at a second angle. Wherein, when the number of bend segments in the balun 703 is odd, at all or part of the odd-numbered bend segments, the seventh, ninth, and eleventh segments are parallel to each other and their lengths increase sequentially; the eighth, tenth, and twelfth segments are parallel to each other and their lengths decrease sequentially. In this way, the sum of the seventh and eighth line segments, the sum of the ninth and tenth line segments, and the sum of the eleventh and twelfth line segments can be equal or approximately equal, so that the lengths of the first-level coupling line 7032a, the second-level coupling line 7032b, and the primary coupling line 7031 are equal or approximately equal, thereby increasing the coupling area of ​​the first-level coupling line 7032a, the second-level coupling line 7032b, and the primary coupling line 7031 and improving the coupling degree of the balun.

[0115] For example, such as Figure 11 As shown, the lengths of the seventh, eighth, ninth, tenth, eleventh, and twelfth line segments are denoted as S7, S8, S9, S10, S11, and S12, respectively. The differences in length between the ninth and seventh line segments (S9-S7), the eleventh and ninth line segments (S11-S9), the eighth and tenth line segments (S8-S10), and the twelfth and tenth line segments (S10-S12) are equal and all have the second value d2. That is, S9-S7=S11-S9=S8-S10=S10-S12=d2, then S7+S8=S9+S10=S11+S12. In this way, the lengths of the first-level coupling line 7032a, the second-level coupling line 7032b, and the primary coupling line 7031 are equal, thereby maximizing the coupling degree of the balun.

[0116] Optionally, the second angle is greater than or equal to 90°, so that the current direction through each coupling line does not change sharply at the bending position, thereby reducing the loss of radio frequency signals and improving the transmission efficiency of radio frequency signals. When the second angle is 90°, the gap between the ninth line segment and the seventh line segment, and the gap between the eleventh line segment and the tenth line segment are equal to the gap between the eighth line segment and the twelfth line segment, so that the lengths of the first secondary coupling line 7032a, the second secondary coupling line 7032b and the primary coupling line 7031 are equal, thereby maximizing the coupling degree and impedance matching effect of the balun.

[0117] It should be noted that in the embodiments of the present application, each coupling line of the same metal layer is always spaced apart from each other and not connected. The intersection points of different coupling lines presented in the above-mentioned various figures are the intersection points of the projections of different coupling lines on a certain plane, rather than the intersection of the coupling lines themselves. In fact, near the intersection point of any two coupling lines, one of the coupling lines can be jumpered to another metal layer through a conductive via, across the intersection point and then jumpered back to the layout metal layer, so as to avoid the physical connection of the two coupling lines.

[0118] In some embodiments, as shown in Figure 12 When the balun 703 has at least two bending segments, if the first segment and the last segment of the balun 703 have the same extension direction, the first secondary coupling line 7032a, the second secondary coupling line 7032b and the primary coupling line 7031 can remain parallel without crossing at each bending segment of the balun 703, and in this case, the lengths of the coupling lines in the balun 703 are still equal or approximately equal, and the balun 703 still has a high coupling degree.

[0119] In some embodiments, as shown in Figure 16 , Figure 17 The primary coupling line 7031 includes a first primary coupling line 7031a and a second primary coupling line 7031b, and the secondary coupling line 7032 includes a first secondary coupling line 7032a and a second secondary coupling line 7032b. The first secondary coupling line 7032a and the second secondary coupling line 7032b are arranged between the first primary coupling line 7031a and the second primary coupling line 7031b, so as to enhance the coupling degree between the primary coupling line and the secondary coupling line.

[0120] As an embodiment, when the balun 703 is used as an output balun of a power amplifier, the first primary coupling line 7031a and the second primary coupling line 7031b can be connected in series or in parallel between the output end of the first power amplification circuit 701 and the output end of the second power amplification circuit 702. For example, the first primary coupling line 7031a and the second primary coupling line 7031b can be connected in series as shown in Figure 16In the embodiment, the balun 703 is a balanced-unbalanced balun, and the function of the balun 703 can refer to the description of the related part in the foregoing embodiment, and details are not described herein. Figure 16 In the embodiment, the balun 703 is a balanced-unbalanced balun, and the function of the balun 703 can refer to the description of the related part in the foregoing embodiment, and details are not described herein.

[0121] As an embodiment, when the balun 703 is used as an input balun or an inter-stage matching balun of the power amplifier, optionally, the first secondary coupling line 7032a and the second secondary coupling line 7032b can be connected in series or in parallel between the input end of the first power amplifier circuit 701 and the input end of the second power amplifier circuit 702. For example, the first secondary coupling line 7032a and the second secondary coupling line 7032b can be connected in series between the input end of the first power amplifier circuit 701 and the input end of the second power amplifier circuit 702 as shown in (a) of FIG. 7B; or the first secondary coupling line 7032a and the second secondary coupling line 7032b can be connected in parallel between the input end of the first power amplifier circuit 701 and the input end of the second power amplifier circuit 702 as shown in (b) of FIG. 7B. Figure 17 In the embodiment, the balun 703 is a balanced-unbalanced balun, and the function of the balun 703 can refer to the description of the related part in the foregoing embodiment, and details are not described herein. Figure 17 In the embodiment, the balun 703 is a balanced-unbalanced balun, and the function of the balun 703 can refer to the description of the related part in the foregoing embodiment, and details are not described herein.

[0122] In at least one embodiment, the primary coupling lines and the secondary coupling lines can be respectively composed of a plurality of coupling lines connected in parallel, and the primary coupling lines and the secondary coupling lines are staggered on the same metal layer, so as to further increase the coupling area of the primary coupling lines and the secondary coupling lines and improve the coupling degree of the transformer structure.

[0123] Optionally, when the number of the primary coupling lines and the secondary coupling lines is plural and they are located on the same plane, the primary coupling lines and the secondary coupling lines can be arranged in a staggered manner as shown in (a) of FIG. 8B. Figure 18As shown, in order to ensure the balance of the primary coupling lines and the secondary coupling lines, the coupling lines on both sides can be of the same type, for example, both sides are primary coupling lines or both sides are secondary coupling lines, and then the difference between the number of primary coupling lines and the number of secondary coupling lines needs to be 1. Exemplarily, the transformer structure can include N primary coupling lines and M secondary coupling lines, and the N primary coupling lines and the M secondary coupling lines are staggered arranged; wherein N and M are positive integers, and N=M+1 or N=M-1. For example, when the number of primary coupling lines is 1 more than the number of secondary coupling lines, that is, N=M+1, the primary coupling lines and the secondary coupling lines are staggered arranged in the order of primary→secondary→…→primary; when the number of secondary coupling lines is 1 more than the number of primary coupling lines, that is, N=M-1, the primary coupling lines and the secondary coupling lines are staggered arranged in the order of secondary→primary→…→secondary. In this way, the coupling degree of the transformer structure can be improved while the balance of the transformer structure is ensured.

[0124] As an implementation manner, the balun 703 is integrated with the first power amplification circuit 701 and the second power amplification circuit 702 in a chip. Exemplarily, the first primary coupling line 7031a, the second primary coupling line 7031b, the first secondary coupling line 7032a and the second secondary coupling line 7032b can all be linearly arranged. Compared with the case where there is only one primary coupling line and one secondary coupling line respectively, four coupling lines can increase the overall width of the balun, and when integrated in a chip, the length of the chip is closer to the width. For example, the first power amplification circuit 701 and the second power amplification circuit 702 can be arranged on the same side of the linear balun 703. The first power amplification circuit 701 and the second power amplification circuit 702 each include a plurality of parallel amplification transistors, and the plurality of transistors in each power amplification circuit can be arranged in an array along the extension direction of the coupling lines of the balun 703. At this time, when the first power amplification circuit 701, the second power amplification circuit 702 and the balun 703 are integrated in a chip, the length and width of the chip are less different, which can avoid the chip from being formed into a long strip structure due to the excessive length of the balun, reduce the risk of chip breakage, and be more beautiful.

[0125] The amplification transistors in the first power amplification circuit 701 and the second power amplification circuit 702 can be MOS (Metal-Oxide-Semiconductor) field effect transistors or HBT (Heterojunction Bipolar Transistor).

[0126] In the above embodiments, the first power amplifier circuit 701 and the second power amplifier circuit 702 can be integrated within the chip. Optionally, the balun 703 can be integrated within the chip together with the first power amplifier circuit 701 and the second power amplifier circuit 702, or it can be disposed outside the chip and connected to the chip.

[0127] This application also provides a chip, such as... Figure 19 As shown, the chip 19 includes at least one power amplifier, which includes a first power amplifier circuit 191, a second power amplifier circuit 192, and a balun 193. The first power amplifier circuit 191 and the second power amplifier circuit 192 are respectively connected to the balun 193. The balun 193 includes a primary coupling line 1931 and a secondary coupling line 1932. The primary coupling line 1931 includes a first input terminal and a second input terminal. The secondary coupling line 1932 includes a first output terminal and a second output terminal. The first routing path of the primary coupling line follows the second routing path of the secondary coupling line. The first routing path is the routing path from the first input terminal to the second input terminal, and the second routing path is the routing path from the first output terminal to the second output terminal.

[0128] In this embodiment, since the paths of the primary coupling line 1931 and the secondary coupling line 1932 follow each other from the starting point to the ending point, each segment of the primary coupling line 1931 can couple with the corresponding segment of the secondary coupling line 1932, and vice versa. Compared to Figure 1 The structure shown has better coupling.

[0129] In some embodiments, the balun 193 may adopt the same structure as the transformer structure 20 in any of the foregoing embodiments. For example, it may be arranged in a straight line, a broken line, an arc, a U-shape, an L-shape, etc. For details, please refer to the description of the foregoing embodiments, which will not be repeated here.

[0130] In some embodiments, the power amplifier may be implemented in the same or similar manner as the power amplifier 70 in any of the foregoing embodiments, which will not be described in detail here.

[0131] In some embodiments, the first power amplifier circuit 191 includes a plurality of first amplifying transistors connected in parallel, and the second power amplifier circuit includes a plurality of second amplifying transistors connected in parallel; both the primary coupling line and the secondary coupling line are arranged in a straight line, and the plurality of first amplifying transistors and the plurality of second amplifying transistors are arranged side by side on one side of the balun along the extension direction of the primary coupling line and the secondary coupling line.

[0132] Optionally, the first amplification transistor and the second amplification transistor can be MOS (Metal-Oxide-Semiconductor) field effect transistors or HBT (Heterojunction Bipolar Transistor) transistors.

[0133] As an implementation form, the power amplifier can be a differential power amplifier circuit, and the first amplification transistor and the second amplification transistor are transistors of opposite types. For example, the first amplification transistor is a P-type MOS transistor / PNP-type HBT, and the second amplification transistor is an N-type MOS transistor / NPN-type HBT; or the first amplification transistor is an N-type MOS transistor / NPN-type HBT, and the second amplification transistor is a P-type MOS transistor / PNP-type HBT.

[0134] In some embodiments, as shown in Figure 20 Fig. 19, the chip 19 includes at least two power amplifiers 190, each power amplifier is arranged side by side along a preset arrangement direction (x direction), and the baluns in each power amplifier extend along the same direction (y direction). Wherein, the arrangement direction (x direction) of each power amplifier is perpendicular to the extension direction (y direction) of any balun. In this way, when the lengths of the primary coupling line and the secondary coupling line are relatively long, by arranging multiple power amplifiers side by side, the length and the width of the chip are closer, which can avoid the chip from being formed into a long strip structure due to the overlong balun, reduce the risk of chip breakage, and be more beautiful.

[0135] In some embodiments, as shown in Figure 21 (a) and Figure 21 (b), the primary coupling line and the secondary coupling line are both arranged in an L shape; the first power amplifier circuit 191 includes a plurality of first amplification transistors connected in parallel, and the plurality of first amplification transistors are arranged side by side along one side of the L shape; the second power amplifier circuit 192 includes a plurality of second amplification transistors connected in parallel, and the plurality of second amplification transistors are arranged side by side along the other side of the L shape. Optionally, the first power amplifier circuit 191 and the second power amplifier circuit 192 can be arranged on the inner side of the balun, so as to reasonably utilize the space on the inner side of the L-shaped structure, so that the overall layout of the chip is more compact and the area is smaller.

[0136] By arranging the primary coupling line and the secondary coupling line in an L shape, the length of each coupling line can be lengthened compared with a straight line type, so as to realize a larger inductance, which can be applicable to scenarios with higher requirements for inductance. Moreover, the L-shaped balun can extend along the edge of the chip, so as to leave the space inside the chip for other circuit layout.

[0137] In some embodiments, the chip comprises at least one metal layer, when the number of primary coupling lines and secondary coupling lines is one, the primary coupling line and the secondary coupling line can be located in the same metal layer. When the number of primary coupling lines or secondary coupling lines is greater than one, at least one primary coupling line and at least one secondary coupling line can be located in the same metal layer. By arranging at least one primary coupling line and at least one secondary coupling line in the same layer, the number of metal layers occupied by the balun can be reduced, the manufacturing process of the chip can be simplified, and the cost can be reduced.

[0138] As an implementation, the chip comprises a first metal layer and a second metal layer, and the first metal layer and the second metal layer are respectively provided with two primary coupling lines and one secondary coupling line. Taking the balun as an output balun of a power amplifier as an example, the two primary coupling lines in the same metal layer are respectively connected to different power amplification circuits and are coupled to each other with the secondary coupling line in the same metal layer. For example, the primary coupling lines comprise a first primary coupling line and a second primary coupling line arranged in the first metal layer, and a third primary coupling line and a fourth primary coupling line arranged in the second metal layer; the secondary coupling line comprises a first secondary coupling line arranged in the first metal layer and a second secondary coupling line arranged in the second metal layer, wherein the first primary coupling line and the second primary coupling line are respectively coupled to the first secondary coupling line, the third primary coupling line and the fourth primary coupling line are respectively coupled to the second secondary coupling line, and the first primary coupling line and the third primary coupling line are both connected to a first power amplification circuit, and the second primary coupling line and the fourth primary coupling line are both connected to a second power amplification circuit. Optionally, the length of the first primary coupling line is the same as the length of the fourth primary coupling line, and the length of the second primary coupling line is the same as the length of the third primary coupling line. In this way, the sum of the first primary coupling line and the third primary coupling line is equal to the sum of the second primary coupling line and the fourth primary coupling line, that is, the total length of the primary coupling line connected to the first power amplification circuit is equal to the total length of the primary coupling line connected to the second power amplification circuit, so that the power amplifier can maintain a good balance even if the lengths of the first primary coupling line and the second primary coupling line in the same metal layer are different. In other words, when the balun has one or more bending segments, the two primary coupling lines and the secondary coupling line in the same metal layer can not cross at the bending segment in order to maintain the same length, thereby avoiding the loss caused by the crossing of the coupling lines and improving the efficiency of the power amplifier.

[0139] As an implementation, the chip includes a first metal layer and a second metal layer, and each of the first metal layer and the second metal layer is provided with one primary coupling line and two secondary coupling lines. Taking a balun as an input balun of a power amplifier as an example, the two secondary coupling lines in the same metal layer are respectively connected to different power amplification circuits and are coupled to each other with the primary coupling line in the same metal layer. For example, the secondary coupling lines include a first secondary coupling line and a second secondary coupling line arranged in the first metal layer, and a third secondary coupling line and a fourth secondary coupling line arranged in the second metal layer; the primary coupling line includes a first primary coupling line arranged in the first metal layer and a second primary coupling line arranged in the second metal layer, wherein the first secondary coupling line and the second secondary coupling line are respectively coupled to the first primary coupling line, the third secondary coupling line and the fourth secondary coupling line are respectively coupled to the second primary coupling line, and the first secondary coupling line and the third secondary coupling line are both connected to a first power amplification circuit, and the second secondary coupling line and the fourth secondary coupling line are both connected to a second power amplification circuit. Optionally, the length of the first secondary coupling line is the same as the length of the fourth secondary coupling line, and the length of the second secondary coupling line is the same as the length of the third secondary coupling line. In this way, the sum of the first secondary coupling line and the third secondary coupling line is equal to the sum of the second secondary coupling line and the fourth secondary coupling line, that is, the total length of the secondary coupling lines connected to the first power amplification circuit is equal to the total length of the secondary coupling lines connected to the second power amplification circuit, so that the power amplifier can maintain a good balance even if the lengths of the first secondary coupling line and the second secondary coupling line in the same metal layer are different. In other words, when the balun has one or more bending segments, the two secondary coupling lines and the primary coupling line in the same metal layer can not cross at the bending segment in order to maintain the same length, thereby avoiding the loss caused by the crossing of the coupling lines and improving the efficiency of the power amplifier.

[0140] The embodiments of the present application also provide a radio frequency front-end module, as shown in the drawings. Figure 22 The radio frequency front-end module 22 includes a substrate 221, a power amplification chip 222 and a balun 223, wherein the power amplification chip 222 and the balun 223 are arranged on the substrate, and the power amplification chip 222 and the balun 223 can be connected through metal traces on the substrate. The balun 223 includes a primary coupling line 2231 and a secondary coupling line 2232, the primary coupling line 2231 includes a first input end In1 and a second input end In2, and the secondary coupling line 2232 includes a first output end Out1 and a second output end Out2; wherein the first trace path of the primary coupling line 2231 follows the second trace path of the secondary coupling line 2232, the first trace path is a trace path from the first input end In1 to the second input end In2, and the second trace path is a trace path from the first output end Out1 to the second output end Out2.

[0141] In the embodiments of the present application, since the paths of the primary coupling line 2231 and the secondary coupling line 2232 from the starting point to the ending point follow each other, each segment of the primary coupling line can be coupled with the corresponding segment of the secondary coupling line, and vice versa. Compared with the structure shown in FIG. 1, the structure shown in FIG. 2 has better coupling degree. Figure 1 The structure shown in FIG. 2 has better coupling degree.

[0142] In some embodiments, the balun 223 can have the same structure as the transformer structure 20 of any of the foregoing embodiments, for example, can be arranged in a straight line shape, a broken line shape, an arc shape, a U shape, an L shape, etc. For details, reference can be made to the description of the foregoing embodiments, which will not be repeated here.

[0143] Optionally, the balun 223 can be an output balun or an input balun or an inter-stage matching balun of the power amplification chip 222.

[0144] In some embodiments, the first power amplification circuit 2221 and the second power amplification circuit 2222 are integrated in the power amplification chip 222, the output end of the first power amplification circuit 2221 and the output end of the second power amplification circuit 2222 are connected with the primary coupling line 2231 of the balun 223 respectively, and the secondary coupling line 2232 of the balun is connected with the signal transmission end. At this time, the balun 223 serves as an output balun of the power amplification chip 222, can convert the differential radio frequency signal output by the power amplification chip 222 into a single-ended radio frequency signal, so as to facilitate the processing of the subsequent circuit, and match the output impedance of the power amplification chip with the input impedance of the subsequent circuit, thereby reducing the loss of the radio frequency signal in the transmission process.

[0145] In some embodiments, the first power amplification circuit 2221 and the second power amplification circuit 2222 are integrated in the power amplification chip 222, the output end of the first power amplification circuit 2221 and the output end of the second power amplification circuit 2222 are connected with the primary coupling line 2231 of the balun 223 respectively, and the secondary coupling line 2232 of the balun is connected with the signal transmission end. At this time, the balun 223 serves as an output balun of the power amplification chip 222, can convert the differential radio frequency signal output by the power amplification chip 222 into a single-ended radio frequency signal, so as to facilitate the processing of the subsequent circuit, and match the output impedance of the power amplification chip with the input impedance of the subsequent circuit, thereby reducing the loss of the radio frequency signal in the transmission process.

[0146] Optionally, the overall shape of the balun 223 can be a strip shape, a broken line shape, a U shape, a C shape, an L shape or other shapes, so as to be connected with the power amplification chip 222 or make the layout of the balun 223 and the power amplification chip 222 more compact, thereby reducing the area occupied by the radio frequency front end module.

[0147] Exemplarily, when the required inductance is small, the balun 223 can be in a bar shape and arranged on one side of the power amplification chip 222.

[0148] Exemplarily, when the required inductance is large, the balun 223 can be in a C shape or a U shape or an L shape or a zigzag shape and arranged around the power amplification chip 222, i.e., the power amplification chip 222 can be arranged in the internal space formed by the C shape or the U shape or the L shape, so that the layout of the balun 223 and the power amplification chip 222 is more compact.

[0149] Exemplarily, when the balun 223 is an output balun of the power amplification chip 222 and other circuit devices need to be arranged between the output end of the power amplification chip 222 and the rear circuit (e.g., a radio frequency switch) of the balun 223, the balun 223 can be in a zigzag shape or an irregular line shape to avoid other circuit devices on the substrate.

[0150] In the embodiments of the present application, the shape and layout position of the balun 223 can be flexibly set to adapt to the layout of the power amplification chip 222 and other circuits on the substrate, so that the overall structure of the radio frequency front-end module is more compact, which is beneficial to the miniaturization design of the radio frequency front-end module.

[0151] In some embodiments, the substrate includes at least one metal layer. When the number of the primary coupling line and the secondary coupling line is one, the primary coupling line and the secondary coupling line can be located on the same metal layer. When the number of the primary coupling line or the secondary coupling line is greater than one, at least one primary coupling line and at least one secondary coupling line can be located on the same metal layer. Arranging at least one primary coupling line and at least one secondary coupling line on the same layer can reduce the number of metal layers occupied by the balun, simplify the manufacturing process of the radio frequency front-end module, and reduce the cost.

[0152] As an implementation, the substrate includes a first metal layer and a second metal layer, and each of the first metal layer and the second metal layer is provided with two primary coupling lines and one secondary coupling line. Taking a balun as an output balun of a power amplifier as an example, the two primary coupling lines in the same metal layer are respectively connected to different power amplification circuits, and are coupled to each other with the secondary coupling line in the same metal layer. For example, the primary coupling lines include a first primary coupling line and a second primary coupling line provided in the first metal layer, and a third primary coupling line and a fourth primary coupling line provided in the second metal layer; the secondary coupling line includes a first secondary coupling line provided in the first metal layer and a second secondary coupling line provided in the second metal layer, wherein the first primary coupling line and the second primary coupling line are respectively coupled to the first secondary coupling line, the third primary coupling line and the fourth primary coupling line are respectively coupled to the second secondary coupling line, and the first primary coupling line and the third primary coupling line are both connected to a first power amplification circuit, and the second primary coupling line and the fourth primary coupling line are both connected to a second power amplification circuit. Optionally, the length of the first primary coupling line is the same as the length of the fourth primary coupling line, and the length of the second primary coupling line is the same as the length of the third primary coupling line. In this way, the sum of the first primary coupling line and the third primary coupling line is equal to the sum of the second primary coupling line and the fourth primary coupling line, that is, the total length of the primary coupling line connected to the first power amplification circuit is equal to the total length of the primary coupling line connected to the second power amplification circuit, so that the power amplifier can maintain a good balance even if the lengths of the first primary coupling line and the second primary coupling line in the same metal layer are different. In other words, when the balun has one or more bending segments, the two primary coupling lines and the secondary coupling line in the same metal layer can not cross at the bending segments in order to maintain the same length, thereby avoiding the loss caused by the crossing of the coupling lines and improving the efficiency of the power amplifier.

[0153] As an implementation, the substrate comprises a first metal layer and a second metal layer, and the first metal layer and the second metal layer are respectively provided with one primary coupling line and two secondary coupling lines. Taking a balun as an input balun of a power amplifier as an example, the two secondary coupling lines in the same metal layer are respectively connected to different power amplification circuits and are coupled to each other with the primary coupling line in the same metal layer. For example, the secondary coupling lines comprise a first secondary coupling line and a second secondary coupling line provided in the first metal layer, and a third secondary coupling line and a fourth secondary coupling line provided in the second metal layer; the primary coupling line comprises a first primary coupling line provided in the first metal layer and a second primary coupling line provided in the second metal layer, wherein the first secondary coupling line and the second secondary coupling line are respectively coupled to the first primary coupling line, the third secondary coupling line and the fourth secondary coupling line are respectively coupled to the second primary coupling line, and the first secondary coupling line and the third secondary coupling line are both connected to a first power amplification circuit, and the second secondary coupling line and the fourth secondary coupling line are both connected to a second power amplification circuit. Optionally, the length of the first secondary coupling line is the same as the length of the fourth secondary coupling line, and the length of the second secondary coupling line is the same as the length of the third secondary coupling line. In this way, the sum of the first secondary coupling line and the third secondary coupling line is equal to the sum of the second secondary coupling line and the fourth secondary coupling line, that is, the total length of the secondary coupling line connected to the first power amplification circuit is equal to the total length of the secondary coupling line connected to the second power amplification circuit, so that the power amplifier can maintain a good balance even if the lengths of the first secondary coupling line and the second secondary coupling line in the same metal layer are different. In other words, when the balun has one or more bending segments, the two secondary coupling lines and the primary coupling line in the same metal layer can not cross at the bending segment in order to maintain the same length, thereby avoiding the loss caused by the crossing of the coupling lines and improving the efficiency of the power amplifier.

[0154] The above embodiments are only used to illustrate the technical solutions of the present application, but not limit the same; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that the technical solutions recorded in the foregoing embodiments can be modified, or some technical features can be replaced by equivalent ones; and these modifications or replacements do not drive the essence of the corresponding technical solutions out of the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A power amplifier, characterized by, The balun comprises a first power amplifier circuit and a second power amplifier circuit, and the first power amplifier circuit and the second power amplifier circuit are connected with the balun respectively; The balun comprises: A primary coupling line, the primary coupling line comprises a first input end and a second input end; A secondary coupling line, the secondary coupling line comprises a first output end and a second output end; The first trace path of the primary coupling line follows the second trace path of the secondary coupling line, the first trace path is from the first input end to the second input end, and the second trace path is from the first output end to the second output end; wherein: The primary coupling line comprises a first primary coupling line and a second primary coupling line, and the secondary coupling line is arranged between the first primary coupling line and the second primary coupling line; The first input end of the first primary coupling line and the first input end of the second primary coupling line are connected with the output end of the first power amplifier circuit respectively, and the second input end of the first primary coupling line and the second input end of the second primary coupling line are connected with the output end of the second power amplifier circuit respectively; The first output end of the secondary coupling line is used for connecting a signal transmission end, and the second output end of the secondary coupling line is used for grounding; Or, The primary coupling line comprises a first primary coupling line and a second primary coupling line, and the secondary coupling line is arranged between the first primary coupling line and the second primary coupling line; The first input end of the first primary coupling line and the first input end of the second primary coupling line are used for receiving radio frequency input signals respectively, and the second input end of the first primary coupling line and the second input end of the second primary coupling line are used for grounding respectively; The first output end of the secondary coupling line is connected with the input end of the first power amplifier circuit, and the second output end of the secondary coupling line is connected with the input end of the second power amplifier circuit; Or, The secondary coupling line comprises a first secondary coupling line and a second secondary coupling line, and the primary coupling line is arranged between the first secondary coupling line and the second secondary coupling line; The first input end of the primary coupling line is used for receiving a radio frequency input signal, and the second input end of the primary coupling line is used for grounding; The first output end of the first secondary coupling line and the first output end of the second secondary coupling line are connected with the input end of the first power amplifier respectively, and the second output end of the first secondary coupling line and the second output end of the second secondary coupling line are connected with the input end of the second power amplifier respectively.

2. The power amplifier of claim 1, wherein, The balun comprises an odd number of bending sections, at the bending sections, if the primary coupling line comprises a first primary coupling line and a second primary coupling line, the first primary coupling line comprises a first line segment and a second line segment connected at a first angle, the secondary coupling line comprises a third line segment and a fourth line segment connected at a first angle, and the second primary coupling line comprises a fifth line segment and a sixth line segment connected at a first angle, wherein at the odd number of bending sections: The first line segment, the third line segment and the fifth line segment are arranged in sequence and have lengths that increase in sequence; The second line segment, the fourth line segment and the sixth line segment are arranged in sequence and have lengths that decrease in sequence.

3. The power amplifier of claim 2, wherein, The difference between the length of the third line segment and the length of the first line segment, the difference between the length of the fifth line segment and the length of the third line segment, the difference between the length of the second line segment and the length of the fourth line segment, and the difference between the length of the fourth line segment and the length of the sixth line segment are all first values.

4. The power amplifier of any of claims 1-3, It is characterized in that; The length of the first primary coupling line, the length of the second primary coupling line and the length of the secondary coupling line are the same.

5. The power amplifier of claim 1, wherein, The balun includes N primary coupling lines and M secondary coupling lines, and the N primary coupling lines and the M secondary coupling lines are arranged in an interleaved manner on the same metal layer; wherein N and M are both positive integers, and N=M+1 or N=M-1.

6. The power amplifier of claim 1, wherein, The balun includes an odd number of bending segments, at the bending segments, if the secondary coupling line includes a first secondary coupling line and a second secondary coupling line, the first secondary coupling line includes a seventh line segment and an eighth line segment connected at a second angle, the primary coupling line includes a ninth line segment and a tenth line segment connected at a second angle, and the second secondary coupling line includes an eleventh line segment and a twelfth line segment connected at a second angle, wherein at the odd number of bending segments: The seventh line segment, the ninth line segment and the eleventh line segment are parallel to each other and have lengths that increase in sequence; The eighth line segment, the tenth line segment and the twelfth line segment are parallel to each other and have lengths that decrease in sequence.

7. The power amplifier of claim 6, characterized in that, The difference between the length of the ninth line segment and the length of the seventh line segment is equal to the difference between the length of the eleventh line segment and the length of the ninth line segment, and the difference between the length of the eighth line segment and the length of the tenth line segment is equal to the difference between the length of the tenth line segment and the length of the twelfth line segment.

8. The power amplifier of any one of claims 1, 6, 7, wherein, If the secondary coupling line includes a first secondary coupling line and a second secondary coupling line, the length of the first secondary coupling line, the length of the second secondary coupling line and the length of the primary coupling line are the same.

9. The power amplifier of any one of claims 1, 6, 7, wherein, The first input end of the primary coupling line is connected to the output end of the first power amplification circuit, and the second input end of the primary coupling line is connected to the output end of the second power amplification circuit. If the secondary coupling line includes a first secondary coupling line and a second secondary coupling line, the first output end of the first secondary coupling line and the first output end of the second secondary coupling line are respectively used to connect signal transmission ends, and the second output end of the first secondary coupling line and the second output end of the second secondary coupling line are respectively used for grounding.

10. The power amplifier of claim 1, wherein, The primary coupling line and the secondary coupling line are arranged in a straight line type, a broken line type, an L shape, a U shape or an arc shape.

11. A chip, characterized by The power amplifier includes at least one power amplifier, the power amplifier includes a first power amplification circuit, a second power amplification circuit and a balun, and the first power amplification circuit and the second power amplification circuit are respectively connected to the balun. The balun includes: A primary coupling line, the primary coupling line includes a first input end and a second input end; A secondary coupling line, the secondary coupling line includes a first output end and a second output end; The first routing path of the primary coupling line follows the second routing path of the secondary coupling line, the first routing path is from the first input end to the second input end, and the second routing path is from the first output end to the second output end. The first power amplifier circuit includes a plurality of first amplification transistors connected in parallel, and the second power amplifier circuit includes a plurality of second amplification transistors connected in parallel. The plurality of first amplification transistors and the plurality of second amplification transistors are arranged side by side along the extension direction of the primary coupling line and the secondary coupling line on one side of the balun.

12. The chip of claim 11, wherein, The primary coupling line and the secondary coupling line are linear, zigzag, L-shaped, U-shaped or arc-shaped in the chip.

13. The chip of claim 11, wherein, The chip includes at least two power amplifiers, each of which is arranged side by side along a predetermined arrangement direction, and the balun in each of the power amplifiers extends in the same direction, wherein the arrangement direction is perpendicular to the extension direction of any balun.

14. The chip according to any of claims 11-13, characterized by The chip includes at least one metal layer, and the primary coupling line and the secondary coupling line are located in the same metal layer; or when the primary coupling line or the secondary coupling line includes a plurality of lines, at least one of the primary coupling lines and at least one of the secondary coupling lines are located in the same metal layer.

15. A radio frequency front end module, comprising: Comprising: a substrate, a power amplifier chip arranged on the substrate, the power amplifier chip integrated with a first power amplifier circuit and a second power amplifier circuit; a balun arranged on the substrate and connected with the power amplifier chip, the balun comprising: a primary coupling line including a first input end and a second input end; a secondary coupling line including a first output end and a second output end; The first routing path of the primary coupling line follows the second routing path of the secondary coupling line, the first routing path is from the first input end to the second input end, and the second routing path is from the first output end to the second output end. The primary coupling line includes a first primary coupling line and a second primary coupling line, and the secondary coupling line is arranged between the first primary coupling line and the second primary coupling line. The first input end of the first primary coupling line and the first input end of the second primary coupling line are respectively connected with the output end of the first power amplifier circuit, and the second input end of the first primary coupling line and the second input end of the second primary coupling line are respectively connected with the output end of the second power amplifier circuit. The first output end of the secondary coupling line is used for connecting a signal transmission end, and the second output end of the secondary coupling line is used for grounding. Or, The primary coupling line includes a first primary coupling line and a second primary coupling line, and the secondary coupling line is arranged between the first primary coupling line and the second primary coupling line. The first input end of the first primary coupling line and the first input end of the second primary coupling line are respectively used for receiving a radio frequency input signal, and the second input end of the first primary coupling line and the second input end of the second primary coupling line are respectively used for grounding; The first output end of the secondary coupling line is connected with the input end of the first power amplifier circuit, and the second output end of the secondary coupling line is connected with the input end of the second power amplifier circuit; Or, The secondary coupling line includes a first secondary coupling line and a second secondary coupling line, and the primary coupling line is arranged between the first secondary coupling line and the second secondary coupling line; The first input end of the primary coupling line is used for receiving a radio frequency input signal, and the second input end of the primary coupling line is used for grounding; The first output end of the first secondary coupling line and the first output end of the second secondary coupling line are respectively connected with the input end of the first power amplifier, and the second output end of the first secondary coupling line and the second output end of the second secondary coupling line are respectively connected with the input end of the second power amplifier.

16. The radio frequency front end module of claim 15, wherein, The primary coupling line and the secondary coupling line are arranged in a straight line type, a broken line type, an L shape, a U shape or an arc shape on the substrate.

17. The radio frequency front end module of claim 15, wherein, The substrate includes at least one metal layer, and the primary coupling line and the secondary coupling line are located in the same metal layer; or when the primary coupling line or the secondary coupling line includes a plurality of lines, at least one of the primary coupling lines and at least one of the secondary coupling lines are located in the same metal layer.

18. A transformer structure, characterized by Comprise: The primary coupling line includes a first input end and a second input end; The secondary coupling line includes a first output end and a second output end; The first trace path of the primary coupling line follows the second trace path of the secondary coupling line, and the first trace path is from the first input end to the second input end, and the second trace path is from the first output end to the second output end; wherein: The primary coupling line includes a first primary coupling line and a second primary coupling line, and the secondary coupling line is arranged between the first primary coupling line and the second primary coupling line; The first input end of the first primary coupling line and the first input end of the second primary coupling line are respectively connected with the output end of the first power amplifier circuit, and the second input end of the first primary coupling line and the second input end of the second primary coupling line are respectively connected with the output end of the second power amplifier circuit; The first output end of the secondary coupling line is used for connecting a signal transmission end, and the second output end of the secondary coupling line is used for grounding; Or, The primary coupling line includes a first primary coupling line and a second primary coupling line, and the secondary coupling line is arranged between the first primary coupling line and the second primary coupling line; The first input end of the first primary coupling line and the first input end of the second primary coupling line are respectively used for receiving a radio frequency input signal, and the second input end of the first primary coupling line and the second input end of the second primary coupling line are respectively used for grounding; The first output end of the secondary coupling line is used for connecting with the input end of the first power amplifier circuit, and the second output end of the secondary coupling line is used for connecting with the input end of the second power amplifier circuit. Alternatively, The secondary coupling line comprises a first secondary coupling line and a second secondary coupling line, and the primary coupling line is arranged between the first secondary coupling line and the second secondary coupling line. The first input end of the primary coupling line is used for receiving a radio frequency input signal, and the second input end of the primary coupling line is used for grounding. The first output end of the first secondary coupling line and the first output end of the second secondary coupling line are respectively used for connecting with the input end of the first power amplifier, and the second output end of the first secondary coupling line and the second output end of the second secondary coupling line are respectively used for connecting with the input end of the second power amplifier.

19. The transformer structure of claim 18, wherein, The primary coupling line and the secondary coupling line are both arranged in a straight line or a zigzag line.

20. The transformer structure of claim 18, wherein, The primary coupling line and the secondary coupling line are both arranged in an L shape.

21. The transformer structure of claim 18, wherein, The primary coupling line and the secondary coupling line are both arranged in a U shape.

22. The transformer structure of claim 18, wherein, The length of the primary coupling line is equal to the length of the secondary coupling line.

23. The transformer structure of claim 18, wherein, The primary coupling line and the secondary coupling line are both arranged in an arc shape.

24. The transformer structure of claim 23, wherein, The central angle of the arc of the primary coupling line and the secondary coupling line is less than or equal to 270°.

25. The transformer structure of claim 24, wherein, The central angle of the arc of the primary coupling line and the secondary coupling line is less than or equal to 180°.

26. The transformer structure according to any of claims 18-25, characterized by The primary coupling line and the secondary coupling line are located in the same plane; or, when the primary coupling line or the secondary coupling line comprises a plurality of lines, at least one of the primary coupling lines and at least one of the secondary coupling lines are located in the same plane.

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