Power amplifier

Abstract

The embodiment of the invention provides a power amplifier which comprises a main amplifying circuit and an auxiliary amplifying circuit, and the phase difference between an output signal of the main amplifying circuit and an output signal of the auxiliary amplifying circuit is 180 degrees. The combiner circuit is connected with the main circuit amplifying circuit and the auxiliary circuit amplifying circuit; and the combiner circuit is used for carrying out voltage combination on the main circuit amplifying circuit and the auxiliary circuit amplifying circuit.

Description

Technical Field

[0001] The present disclosure relates to the field of electronic technology, and relates to but is not limited to a power amplifier. Background Art

[0002] With the development of mobile communications, low-power amplifiers are becoming more and more popular. Low-power amplifiers usually have relatively low voltages, but low voltages can lead to poor performance consistency at different frequencies of the power amplifier, large insertion loss, and affect amplifier performance. Summary of the invention

[0003] In view of this, an embodiment of the present disclosure provides a power amplifier, including:

[0004] A main amplifier circuit and an auxiliary amplifier circuit, wherein the phase difference between the output signal of the main amplifier circuit and the output signal of the auxiliary amplifier circuit is 180 degrees;

[0005] A combiner circuit, wherein the combiner circuit connects the main amplifier circuit and the auxiliary amplifier circuit; the combiner circuit is used to combine the voltage of the main amplifier circuit and the auxiliary amplifier circuit.

[0006] In some embodiments, the combiner circuit includes a balun.

[0007] In some embodiments, the balun is further configured to adjust the combined impedance to the transmission impedance.

[0008] In some embodiments, the balun includes a primary coil, a secondary coil, a first capacitor and / or a second capacitor; wherein,

[0009] The first end of the primary coil is connected to the output end of the main amplifier circuit, the second end of the primary coil is connected to the output end of the auxiliary amplifier circuit, the first end of the secondary coil is connected to the load, the first capacitor is connected between the first end of the primary coil and the second end of the primary coil, and the second capacitor is connected between the second end of the secondary coil and the ground.

[0010] In some embodiments, the combined impedance of the main amplifier circuit and the auxiliary amplifier circuit is 4 to 10 ohms; and / or the impedance transformation ratio of the balun is 1:4 to 1:8.

[0011] In some embodiments, the power amplifier further includes a power supply, which is connected to the balun and feeds the main amplifier circuit and the auxiliary amplifier circuit through the balun.

[0012] In some embodiments, the main path amplification circuit includes a main path amplifier;

[0013] The auxiliary path amplification circuit comprises an auxiliary path amplifier;

[0014] The main amplifier circuit further includes a first matching circuit, which is connected between the main amplifier and the combiner circuit; the first matching circuit includes a first resonant circuit, which is used to suppress harmonics of the output signal of the main amplifier;

[0015] And / or, the auxiliary amplifier circuit also includes a second matching circuit, which is connected between the auxiliary amplifier and the combiner circuit; the second matching circuit includes a second resonant circuit, which is used to suppress harmonics of the output signal of the auxiliary amplifier.

[0016] In some embodiments, the second matching circuit is further used for phase shifting to shift the output signal of the auxiliary amplifier.

[0017] In some embodiments, the second matching circuit includes at least one first-stage impedance matching circuit and at least one first filter inductor, and each of the first filter inductors is respectively connected to a capacitor in the first-stage impedance matching circuit so that the capacitor is grounded through the first filter inductor to form the second resonant circuit.

[0018] In some embodiments, the second matching circuit includes a secondary impedance matching circuit; the secondary impedance matching circuit includes a first inductor, a third capacitor, a second inductor and a fourth capacitor; wherein,

[0019] The output end of the auxiliary amplifier is connected to the first end of the first inductor, the second end of the first inductor is connected to the first end of the third capacitor and the first end of the second inductor, and the second end of the second inductor and the first end of the fourth capacitor are connected to the first input end of the combiner circuit;

[0020] The second end of the third capacitor is grounded through the first filter inductor; and / or the second end of the fourth capacitor is grounded through the first filter inductor.

[0021] In some embodiments, the second matching circuit also includes a fifth capacitor; the first end of the fifth capacitor is connected to the output end of the auxiliary amplifier, and the second end of the fifth capacitor is grounded; the fifth capacitor is also used as a charging and discharging capacitor of the auxiliary amplifier to enable the auxiliary amplifier to operate in Class E.

[0022] In some embodiments, the second matching circuit further includes a second filtering inductor, and the fifth capacitor is grounded through the second filtering inductor.

[0023] In some embodiments, the first resonant circuit includes a sixth capacitor and a third filtering inductor;

[0024] The output end of the main amplifier is connected to the first end of the sixth capacitor and the second input end of the combiner circuit, the first end of the third filter inductor is connected to the second end of the sixth capacitor, and the second end of the third filter inductor is grounded.

[0025] In some embodiments, the sixth capacitor is also used as a charging and discharging capacitor of the main amplifier, so that the main amplifier operates in Class E;

[0026] or,

[0027] The main amplifier operates in class AB.

[0028] In some embodiments, the main amplifier circuit further includes:

[0029] A third matching circuit is connected between the power divider circuit and the main amplifier;

[0030] The auxiliary amplifier circuit also includes:

[0031] The fourth matching circuit is connected between the power divider circuit and the auxiliary amplifier; the phase difference between the output signal of the third matching circuit and the output signal of the fourth matching circuit is 90 degrees.

[0032] In the disclosed embodiment, the phase difference between the output signal of the main amplifier circuit and the output signal of the auxiliary amplifier circuit is 180 degrees, and the combiner circuit is used to directly combine the voltage of the main amplifier circuit and the auxiliary amplifier circuit. In this way, on the one hand, the Doherty architecture can make the amplifier still have high efficiency under deep power back-off; on the other hand, the combiner circuit improves the output impedance and combined impedance by voltage combining and differential structure combining, thereby increasing the bandwidth and reducing the sensitivity of low-impedance combining and mass production fluctuations. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 A schematic diagram of a power amplifier provided by the present disclosure;

[0034] Figure 2 A schematic diagram of a balun in a power amplifier provided by the present disclosure;

[0035] Figure 3 A schematic diagram of a main amplifier circuit and an auxiliary amplifier circuit in a power amplifier provided by the present disclosure;

[0036] Figure 4 A schematic diagram of a second matching circuit in a power amplifier provided by the present disclosure;

[0037] Figure 5 A circuit diagram of a second matching circuit in a power amplifier provided by the present disclosure;

[0038] Figure 6 Another circuit diagram of a second matching circuit in a power amplifier provided by the present disclosure;

[0039] Figure 7 A circuit diagram of a first matching circuit in a power amplifier provided by the present disclosure;

[0040] Figure 8 A circuit diagram of a power amplifier provided by the present disclosure;

[0041] Fig. 9 A circuit diagram of another power amplifier provided by the present disclosure. DETAILED DESCRIPTION

[0042] In order to facilitate the understanding of the present disclosure, the exemplary embodiments of the present disclosure will be described in more detail below with reference to the relevant drawings. Although the exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the specific embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0043] In the following description, a large number of specific details are given to provide a more thorough understanding of the present disclosure. However, it is obvious to those skilled in the art that the present disclosure can be implemented without one or more of these details. In some embodiments, in order to avoid confusion with the present disclosure, some technical features known in the art are not described; that is, all features of the actual embodiment may not be described here, and well-known functions and structures may not be described in detail.

[0044] Generally, terms can be understood at least in part from their use in context. For example, depending at least in part on the context, the term "one or more" as used herein can be used to describe any feature, structure or characteristic in a singular sense, or can be used to describe a combination of features, structures or characteristics in a plural sense. Similarly, terms such as "one" or "the" can also be understood to convey singular usage or to convey plural usage, depending at least in part on the context. In addition, the term "based on" can be understood to not necessarily be intended to convey an exclusive set of factors, and can alternatively allow for the presence of additional factors that are not necessarily explicitly described, which also depends at least in part on the context.

[0045] Unless otherwise defined, the purpose of the terms used herein is only to describe specific embodiments and is not intended to limit the present disclosure. When used herein, the singular forms "one", "an" and "said / the" are also intended to include plural forms, unless the context clearly indicates another way. It should also be understood that the terms "consisting of" and / or "comprising", when used in this specification, determine the presence of the features, integers, steps, operations, elements and / or parts, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, parts and / or groups. When used herein, the term "and / or" includes any and all combinations of the relevant listed items.

[0046] In order to thoroughly understand the present disclosure, detailed steps and detailed structures will be presented in the following description to illustrate the technical solution of the present disclosure. The preferred embodiments of the present disclosure are described in detail below, but in addition to these detailed descriptions, the present disclosure may also have other implementations. It should be understood that in order to make each structure clearly shown in the drawings, the size ratio relationship of each structure may not be consistent with the actual structure.

[0047] The impedance of the combining node of a conventional Doherty power amplifier is low, which will introduce more sensitivity problems and increase the bandwidth and insertion loss requirements of the main matching circuit and impedance transformation circuit.

[0048] like Figure 1 As shown, an embodiment of the present disclosure provides a power amplifier 100, including: a main amplifier circuit 110 and an auxiliary amplifier circuit 120, the phase difference between the output signal of the main amplifier circuit 110 and the output signal of the auxiliary amplifier circuit 120 is 180 degrees; a combiner circuit 130, the combiner circuit 130 connects the main amplifier circuit 110 and the auxiliary amplifier circuit 120; the combiner circuit 130 is used to combine the voltage of the main amplifier circuit 110 and the auxiliary amplifier circuit 120.

[0049] In some embodiments, the power amplifier 100 can be configured as a 2-way, 3-way or more Doherty power amplifier according to actual needs. Here, a 2-way Doherty power amplifier is used as an example for description. The power amplifier 100 also includes a power divider circuit ( Figure 1 The power divider circuit divides the input signal into two paths. In other embodiments, the power divider circuit may be omitted, and the input signal is distributed through other circuits.

[0050] In some embodiments, the main amplifier circuit 110 includes a main input matching circuit, a main amplifier, and a main output matching circuit, and the auxiliary amplifier circuit 120 includes an auxiliary input matching circuit, an auxiliary amplifier, and an auxiliary output matching circuit. Among them, at least one of the main input matching circuit, the main output matching circuit, the auxiliary input matching circuit, and the auxiliary output matching circuit can be omitted as needed. For example, the main amplifier circuit 110 includes a main input matching circuit and a main amplifier, and the auxiliary amplifier circuit 120 includes an auxiliary amplifier and an auxiliary output matching circuit, which will not be described in detail in this application.

[0051] In some embodiments, the main amplifier can work in class AB or class E, and the auxiliary amplifier can work in class C or class E; in other embodiments, the main amplifier and / or the auxiliary amplifier can also work in inverse class E. For example, the main amplifier works in class AB and the auxiliary amplifier works in class E, so that the power amplifier 100 has higher efficiency while taking into account the removal of harmonics; for another example, the main amplifier and the auxiliary amplifier both work in class E; for another example, the main amplifier works in class AB and the auxiliary amplifier works in class C, etc.

[0052] In some embodiments, the phases of the output signals of the main amplifier circuit 110 and the auxiliary amplifier circuit 120 are adjusted by any one of the power divider circuit, the main input matching circuit, the main output matching circuit, the auxiliary input matching circuit and the auxiliary output matching circuit, or multiple circuits, so that the phase difference between the output signal of the main amplifier circuit 110 and the output signal of the auxiliary amplifier circuit 120 is 180 degrees, so that the combiner circuit 130 can directly perform voltage combining. For example, the power divider circuit makes the phase difference of the signals input to the two paths 90 degrees (such as 90 degrees for the auxiliary path and no change in phase for the main path), the main path input matching circuit, the auxiliary path input matching circuit, and the main path output matching circuit keep the phase unchanged, and the auxiliary path output matching circuit is used to shift the phase by 90 degrees; for another example, the power divider circuit makes the phase of the signals input to the two paths the same, the main path input matching circuit and the main path output matching circuit are not used for phase shifting, and the auxiliary path input matching circuit and the auxiliary path output matching circuit are used to shift the phase by 90 degrees respectively; for another example, the power divider circuit makes the auxiliary path input signal phase adjusted by 90 degrees, the main path input signal remains unchanged, the main path input matching circuit and the main path output matching circuit keep the phase unchanged, the auxiliary path input matching circuit is used to shift the phase by 45 degrees, and the auxiliary path output matching circuit is used to shift the phase by 45 degrees. It should be noted that the above circuit structure that keeps the phase unchanged can also be omitted according to actual needs.

[0053] Compared with traditional amplifiers, the power amplifier 100 improves the output impedance and the combined impedance by voltage combining and differential structure combining, thereby increasing the bandwidth and effectively reducing the sensitivity of low-impedance combining and mass production fluctuations.

[0054] In some embodiments, combiner circuit 130 includes a balun.

[0055] In the embodiment of the present disclosure, the combiner circuit 130 includes a balun, and the balun includes a primary coil, a secondary coil, and a capacitor. Since the combiner circuit 130 uses the balun to achieve impedance transformation, the system bandwidth is further improved.

[0056] In some embodiments, the balun is also used to adjust the combined impedance to the transmission impedance.

[0057] In the disclosed embodiment, the balun adjusts the combined impedance of the main amplifier circuit 110 and the auxiliary amplifier circuit 120 to the transmission impedance. Exemplarily, the transmission impedance is 50 ohms, and the combined impedance is 4 to 10 ohms, for example, 8 ohms, 9 ohms, 5 ohms, and 6 ohms. In this embodiment, the combined impedance of the two paths is directly raised to the transmission impedance through the balun, and only one impedance change is required, which can not only simplify the design, but also reduce insertion loss and improve bandwidth.

[0058] In some embodiments, Figure 2 As shown, the balun includes a primary coil Lpc, a secondary coil Lsc, a first capacitor C1, and a second capacitor C2; wherein, the first end of the primary coil Lpc is connected to the output end of the main amplifier circuit 110, the second end of the primary coil Lpc is connected to the output end of the auxiliary amplifier circuit 120, the first end of the secondary coil Lsc is connected to the load 140, the first capacitor C1 is connected between the first end of the primary coil Lpc and the second end of the primary coil Lpc, and the second capacitor C2 is connected between the second end of the secondary coil Lsc and the ground end.

[0059] In the disclosed embodiment, the impedance transformation ratio of the balun is 1:4 to 1:8, for example, 1:5, 1:6, 1:7, etc. The first capacitor C1 and the second capacitor C2 are used for impedance tuning. The first end and the second end of the primary coil Lpc are connected to the output ends of the main amplifier circuit 110 and the auxiliary amplifier circuit 120, respectively.

[0060] In some embodiments, the first capacitor C1 and / or the second capacitor C2 can be set as variable capacitors, so that they can adjust the impedance transformation according to different radio frequency signals, for example, adjusting the impedance transformation of signals in different frequency bands; or adjusting different modes.

[0061] By performing voltage combining and impedance transformation through the balun, the loss can be reduced and the bandwidth can be further improved. Moreover, the power amplifier 100 still has a high efficiency after high power back-off.

[0062] In some embodiments, Figure 2As shown, the power amplifier 100 further includes a power supply Vcc, which is connected to a balun and feeds power to the main amplifier circuit 110 and the auxiliary amplifier circuit 120 through the balun.

[0063] In some embodiments, the power supply Vcc is connected to the primary coil Lpc of the balun, and feeds power to the main amplifier circuit 110 and the auxiliary amplifier circuit 120 through the primary coil Lpc. Among them, the power supply Vcc divides the primary coil Lpc into two parts, and the two parts of the coil are used as the choke inductor of the main amplifier and the choke inductor of the auxiliary amplifier, that is, the inductance in the balun is reused, which is used as both a combiner and a choke inductor to avoid interference of the radio frequency signal to the power supply Vcc. It should be noted that the inductance values ​​of the two parts of the coil can be the same or different. In some embodiments, the primary coil can be set with multiple connection points, and each connection point makes the two choke inductors have different inductance values, so that the power supply can be connected to one of the connection points as needed. In addition, the power supply Vcc can also reuse other inductors in the balun except the primary coil Lpc, and the present disclosure does not limit this.

[0064] In some embodiments, Figure 3 As shown, the main amplifier circuit 110 includes a main amplifier 111; the auxiliary amplifier circuit 120 includes an auxiliary amplifier 121; the main amplifier circuit 110 also includes a first matching circuit 112, the first matching circuit 112 is connected between the main amplifier 111 and the combiner circuit 130; the first matching circuit 112 includes a first resonant circuit 113, the first resonant circuit 113 is used to suppress the harmonics of the output signal of the main amplifier 111; and / or, the auxiliary amplifier circuit 120 also includes: a second matching circuit 122, the second matching circuit 122 is connected between the auxiliary amplifier 121 and the combiner circuit 130; the second matching circuit 122 includes a second resonant circuit 123, the second resonant circuit 123 is used to suppress the harmonics of the output signal of the auxiliary amplifier 121.

[0065] In some embodiments, the main amplifier circuit 110 includes a first matching circuit 112, and the auxiliary amplifier circuit 120 includes a second matching circuit 122. The first matching circuit and the second matching circuit have a first resonant circuit and a second resonant circuit, respectively. In other embodiments, the main amplifier circuit 110 includes the first matching circuit 112, which has a first resonant circuit, and the auxiliary amplifier circuit 120 omits the second matching circuit and does not have a second resonant circuit; or, the auxiliary amplifier circuit 120 includes the second matching circuit 122, which has a second resonant circuit, and the main amplifier circuit 110 omits the first matching circuit and does not have a first resonant circuit. It can be understood that the first matching circuit 112 serves as a main output matching circuit of the main amplifier circuit 110, and the second matching circuit 122 serves as an auxiliary output matching circuit of the auxiliary amplifier circuit 120.

[0066] In some embodiments, the matching circuit of any one of the first matching circuit 112 and the second matching circuit 122 includes a multi-stage impedance matching circuit, and each stage of the impedance matching circuit may be L-type, π-type, or T-type.

[0067] In some embodiments, the first resonant circuit 113 is used to suppress odd waves and / or even waves. For example, the first resonant circuit is used to suppress the second harmonic or the third harmonic. For another example, the first resonant circuit is used to suppress the second harmonic and the third harmonic. For another example, the first resonant circuit is used to suppress at least one of the second harmonic, the third harmonic, and other higher harmonics.

[0068] In some embodiments, the second resonant circuit is used to suppress odd waves and / or even waves. For example, the second resonant circuit is used to suppress second harmonics or third harmonics. For another example, the second resonant circuit is used to suppress second harmonics and third harmonics. For another example, the second resonant circuit is used to suppress at least one of second harmonics, third harmonics, and other higher harmonics.

[0069] The first resonant circuit 113 and / or the second resonant circuit 123 can effectively suppress harmonics in the power amplifier 100 , thereby reducing harmonic power and loss, and further improving the efficiency of the power amplifier 100 .

[0070] In some embodiments, the first resonant circuit and / or the second resonant circuit includes a multi-stage LC circuit, and the multi-stage LC circuit is used to suppress different harmonics respectively.

[0071] In some embodiments, the second matching circuit 122 includes at least one first impedance matching circuit and at least one first filter inductor L11, and each first filter inductor L11 is respectively connected to the capacitor in the first impedance matching circuit so that the capacitor is grounded through the first filter inductor to form a second resonant circuit 123.

[0072] In some embodiments, Figure 4 As shown, the first filter inductor and the capacitor in the matching circuit form a resonant circuit. When there are multiple first filter inductors and the second resonant circuit has multiple stages, the multiple stages are used to suppress different harmonics respectively.

[0073] In the embodiments of the present disclosure, reference Figure 4The second matching circuit 122 includes n-stage impedance matching circuits (n is a positive integer), each stage of the impedance matching circuit is L-type, π-type or T-type, and the present application does not limit it. Here, the L-type is used as an example for explanation. The second matching circuit 122 may also include m first filter inductors L11 (m is a positive integer), wherein each first filter inductor L11 may be respectively connected to a capacitor in a first-stage impedance matching circuit, so that the capacitor is grounded through the first filter inductor L11 to form a resonant circuit. The first filter inductor and the corresponding capacitor in the second matching circuit 122 constitute a second resonant circuit 123.

[0074] It is understandable that the present disclosure reuses the capacitors in the second matching circuit 122, that is, the capacitors in the second matching circuit 122 can be used for impedance matching and forming the second resonant circuit 123. It should be noted that the first filter inductor L11 may not correspond one-to-one to each stage of the impedance matching circuit. In some embodiments, part of the impedance matching circuit may not be grounded through the first filter inductor L11, that is, no harmonics are processed. In other embodiments, a first-level impedance matching circuit may be grounded through multiple first filter inductors L11 connected in series, wherein the multiple first filter inductors may not only select the first inductor to work as needed, but also work simultaneously. The present disclosure may set the first filter inductor L11 according to actual needs, and no excessive restrictions are made here.

[0075] In some embodiments, Figure 5 As shown, the second matching circuit 122 includes a secondary impedance matching circuit; the secondary impedance matching circuit includes a first inductor L1, a third capacitor C3, a second inductor L2 and a fourth capacitor C4; wherein, the output end of the auxiliary amplifier 121 is connected to the first end of the first inductor L1, the second end of the first inductor L1 and the first end of the third capacitor C3 and the first end of the second inductor L2 are all connected, the second end of the second inductor L2 and the first end of the fourth capacitor C4 are both connected to the first input end of the combiner circuit; the second end of the third capacitor C3 is grounded through the first filter inductor L11; and / or, the second end of the fourth capacitor C4 is grounded through the first filter inductor L11.

[0076] Figure 5 In the embodiment, the third capacitor C3 and the fourth capacitor C4 are grounded through a first filter inductor L11 respectively. In other embodiments, the first filter inductor connected to the fourth capacitor C4 can also be omitted, and the third capacitor C3 is grounded through the first filter inductor L11; the first filter inductor connected to the third capacitor C3 can also be omitted, and the fourth capacitor C4 is grounded through the first filter inductor L11. In this way, the second resonant circuit in the second matching circuit 122 includes at least one stage to suppress the second harmonic and / or other higher harmonics. When the third capacitor and the fourth capacitor are both connected to a first filter inductor, the second resonant circuit includes two stages, and the two stages can be used to filter different harmonics.

[0077] In some embodiments, Figure 6 As shown, the second matching circuit 122 includes a fifth capacitor C5; the first end of the fifth capacitor C5 is connected to the output end of the auxiliary amplifier 121, and the second end of the fifth capacitor C5 is grounded; the fifth capacitor C5 is also used as a charging and discharging capacitor of the auxiliary amplifier 121, so that the auxiliary amplifier 121 operates in Class E.

[0078] In the disclosed embodiment, the fifth capacitor C5 is used to present a large capacitance at the baseband, so as to serve as a charging and discharging capacitor of the auxiliary amplifier 121 , thereby making the auxiliary amplifier 121 operate in Class E to improve the efficiency of the amplifier.

[0079] In some embodiments, the fifth capacitor may be one or more, or the fifth capacitor is a variable capacitor. When there are multiple fifth capacitors, multiple fifth capacitors are arranged in parallel; when the fifth capacitor is a variable capacitor, it can be selected according to the frequency band, power, mode, etc. of the input signal.

[0080] In some embodiments, the second matching circuit 122 further includes a second filtering inductor L12, and the fifth capacitor C5 is grounded via the second filtering inductor L12. The fifth capacitor C5 and the second filtering inductor L12 form a second resonant circuit to further suppress harmonics.

[0081] It should be noted that the connection method and quantity of the second filter inductor and the fifth capacitor are the same as those of the first filter inductor in various embodiments, and will not be repeated here. The second resonant circuit may include the first filter inductor and / or the second filter inductor.

[0082] In some embodiments, the second matching circuit 122 is further used for phase shifting to adjust the phase of the output signal of the auxiliary amplifier 121 by 90 degrees.

[0083] In some embodiments, Figure 5 , Figure 6 As shown, the first stage matching circuit composed of the first inductor L1 and the third capacitor C3 is used for phase shifting 45 degrees, and the second stage matching circuit 122 composed of the second inductor L2 and the fourth capacitor C4 is used for phase shifting 45 degrees, thereby adjusting the phase by 90 degrees in total. It should be noted that the phase adjusted by each stage impedance matching circuit of the second stage matching circuit 122 in the present disclosure is not limited to 45 degrees, and can be flexibly designed according to actual needs. For example, the first stage matching phase shifts 60 degrees, and the second stage matching phase shifts 30 degrees.

[0084] In some embodiments, the second matching circuit cooperates with the auxiliary input matching circuit to shift the phase of the output signal of the auxiliary amplifier circuit by 90 degrees. For example, the second matching circuit shifts the phase by 45 degrees, and the auxiliary input matching circuit shifts the phase by 45 degrees; for another example, the second matching circuit shifts the phase by 60 degrees, and the auxiliary input matching circuit shifts the phase by 30 degrees; for another example, the second matching circuit shifts the phase by 30 degrees, and the auxiliary input matching circuit shifts the phase by 60 degrees.

[0085] In some embodiments, the fifth capacitor C5 can also cooperate with the following two-stage impedance matching circuit (i.e., the two-stage impedance matching circuit composed of the first inductor L1, the third capacitor C3, the second inductor L2 and the fourth capacitor C4) to perform phase adjustment. At this time, the third capacitor C3 and the fourth capacitor C4 can have smaller capacitance values.

[0086] In some embodiments, the fifth capacitor C5 can utilize the parasitic capacitance of the auxiliary amplifier 121 , thereby reducing the area of ​​the fifth capacitor C5 .

[0087] In some embodiments, Figure 6 As shown, the second matching circuit 122 may further include a third inductor L3, a first end of the third inductor L3 is connected to the output end of the auxiliary amplifier 121, and a second end of the third inductor L3 is connected to the power supply Vcc. Thus, the third inductor L3 is used for impedance matching and isolating RF signals.

[0088] In some embodiments, Figure 7 As shown, the first resonant circuit 113 includes a sixth capacitor C6 and a third filter inductor L13; the output end of the main amplifier 111 is connected to the first end of the sixth capacitor C6 and the second input end of the combiner circuit, the first end of the third filter inductor L13 is connected to the second end of the sixth capacitor C6, and the second end of the third filter inductor L13 is grounded.

[0089] Similar to the second matching circuit and the second resonant circuit, the first matching circuit and the first resonant circuit may be the same as the above-mentioned embodiments. For example, in some embodiments, the first matching circuit 112 may include one or more impedance matching circuits, and one or more third filter inductors, wherein each third filter inductor may be respectively connected to a capacitor in a first impedance matching circuit, so that the capacitor is grounded through the third filter inductor to form a first resonant circuit. All third filter inductors and corresponding capacitors in the first matching circuit constitute the first resonant circuit. It should be noted that the third filter inductor may not correspond to each impedance matching circuit one by one. For another example, in some embodiments, part of the impedance matching circuit may not be grounded through the third filter inductor, that is, it does not constitute the first resonant circuit. For another example, in some other embodiments, part of the impedance matching circuit may be grounded through multiple third filter inductors connected in series. It will not be repeated here, and reference may be made to the relevant content of the second matching circuit in the above-mentioned embodiments.

[0090] In some embodiments, Figure 7 As shown, the sixth capacitor C6 is also used as a charging and discharging capacitor of the main amplifier 111, so that the main amplifier 111 works in class E; or, the main amplifier 111 works in class AB.

[0091] In the disclosed embodiment, a portion of the sixth capacitor C6 and the third filter inductor L13 form a first resonant circuit, and another portion serves as a charging and discharging capacitor of the main amplifier 111, so that the main amplifier 111 operates in Class E.

[0092] The sixth capacitor C6 can also be used only to form a first resonant circuit with the third filter inductor L13, that is, not used as a charging and discharging capacitor of the main amplifier 111. At this time, the main amplifier 111 works in class AB. Since the sixth capacitor C6 is only used to form the first resonant circuit, the sixth capacitor C6 can have a smaller area at this time.

[0093] In some embodiments, Figure 7 As shown, the first matching circuit 112 may further include a fourth inductor L4, a first end of the fourth inductor L4 is connected to the output end of the main amplifier 111, and a second end of the fourth inductor L4 is connected to the power supply Vcc. Thus, the fourth inductor L4 is used for impedance matching and isolating RF signals.

[0094] In some embodiments, Figure 8 As shown, the power amplifier 100 also includes a power divider circuit 150, which is used to divide the input signal into two paths, and the two signals are transmitted to the main amplifier circuit 110 and the auxiliary amplifier circuit 120 respectively. Among them, there is a phase difference between the two input signals output by the power divider circuit 150, such as the phase difference between the two input signals can be 90 degrees, 45 degrees, 270 degrees, 180 degrees, etc. It should be noted that the phase of the input signal transmitted to the main amplifier circuit through the power divider circuit 150 can be changed or remain unchanged; similarly, the phase of the input signal transmitted to the auxiliary amplifier circuit can be changed or remain unchanged, and this application does not limit it. For example, the phase of the main input signal remains unchanged, and the phase of the auxiliary input signal is 90 degrees; for another example, the phase of the main input signal is 45 degrees, and the phase of the auxiliary input signal is -45 degrees; for another example, the phase of the main input signal is 90 degrees, and the auxiliary remains unchanged.

[0095] In some embodiments, Figure 8 As shown, the main amplifier circuit 110 further includes: a third matching circuit 114 connected between the power divider circuit 150 and the main amplifier 111 ; the auxiliary amplifier circuit 120 further includes: a fourth matching circuit 124 connected between the power divider circuit 150 and the auxiliary amplifier 121 .

[0096] Any one of the third matching circuit 114 and the fourth matching circuit 124 may include one or more impedance matching circuits, and each impedance matching circuit may be L-type, π-type, or T-type. Figure 8 As shown, the third matching circuit 114 and the fourth matching circuit 124 both include a first-stage T-type matching circuit. It is understandable that the third matching circuit 114 serves as a main input matching circuit of the main amplifier circuit 110 , and the fourth matching circuit 124 serves as an auxiliary input matching circuit of the auxiliary amplifier circuit 120 .

[0097] In some embodiments, the third matching circuit 114 and the fourth matching circuit 124 keep the input phase unchanged. In other embodiments, the third matching circuit 114 and the fourth matching circuit 124 can also change the phase of the signal. For example, when the phase of the two signals output by the power divider circuit 150 remains unchanged, the third matching circuit 114 shifts the phase by -45 degrees and the fourth matching circuit 124 shifts the phase by 45 degrees; or, the third matching circuit 114 shifts the phase by -30 degrees and the fourth matching circuit 124 shifts the phase by 60 degrees. When the phase difference between the two signals output by the power divider circuit 150 is 30 degrees, the third matching circuit 114 shifts the phase by 30 degrees and the fourth matching circuit 124 shifts the phase by 90 degrees.

[0098] It should be noted that the power divider circuit 150, the first matching circuit 112, the second matching circuit 122, the third matching circuit 114 and the fourth matching circuit 124 cooperate with each other to make the phase difference between the output signal of the main amplifier circuit 110 and the output signal of the auxiliary amplifier circuit 120 180 degrees, wherein the phase shift adjustment of each circuit can be flexibly designed according to actual needs, and the present disclosure does not impose too many restrictions. For example, the phase difference between the two signals output by the power divider circuit 150 is 90 degrees (45 degrees for the auxiliary path and -45 degrees for the main path), the first matching circuit 112 and the third matching circuit 114 do not change the phase, the second matching circuit 122 shifts the phase by 45 degrees, and the fourth matching circuit 124 shifts the phase by 45 degrees; for another example, the phase difference between the two signals output by the power divider circuit 150 is 90 degrees (90 degrees for the auxiliary path and 0 degrees for the main path), the first matching circuit 112 shifts the phase by 45 degrees, the third matching circuit 114 shifts the phase by 45 degrees, the second matching circuit 122 shifts the phase by 90 degrees, and the fourth matching circuit 124 shifts the phase by 90 degrees; for another example, the phase difference between the two signals output by the power divider circuit 150 is 0, the first matching circuit 112 shifts the phase by -45 degrees, the third matching circuit 114 shifts the phase by -45 degrees, the second matching circuit 122 shifts the phase by 45 degrees, and the fourth matching circuit 124 shifts the phase by 45 degrees.

[0099] Figure 8 and Fig. 9 The following are two exemplary circuit diagrams of the power amplifier 100 provided in the present disclosure. Figure 8The second filter inductor L12 and the fifth capacitor C5 of the second matching circuit 122 form a second resonant circuit; Fig. 9 The first filter inductor L11 and the third capacitor C3 of the second matching circuit 122 form a second resonant circuit. At this time, the first inductor L1 can be reused, that is, the first inductor L1 is used for both impedance matching and harmonic suppression. It can be understood that the present disclosure can form a harmonic circuit by setting one or more filter inductors at different positions, and flexibly configure the harmonic suppression point to simultaneously suppress the second harmonic, the third harmonic, etc. In addition, Figure 8 The power source Vcc feeds the main amplifier 111 and the auxiliary amplifier 121 through the fourth inductor L4 and the third inductor L3 respectively. The fourth inductor L4 and the third inductor L3 are used for impedance matching and also as choke inductors. Fig. 9 The power supply Vcc is fed to the main amplifier 111 and the auxiliary amplifier 121 through the primary coil Lpc of the balun, that is, the primary coil Lpc of the balun is reused and used as a choke inductor to avoid interference of the RF signal on the power supply Vcc, thereby eliminating the need for additional choke inductors and reducing the circuit area.

[0100] In some embodiments, reference Figure 8 , the first capacitor C1, the third capacitor C3, the fourth capacitor C4, the fifth capacitor C5 and the sixth capacitor C6 can be integrated on the chip; the third inductor L3, the fourth inductor L4, the third filter inductor L13, the second filter inductor L12, the primary coil Lpc and the secondary coil Lsc in the balun are formed on the substrate by winding, and finally there is only the second capacitor C2, a surface mount (Surface Mount Device, SMD) capacitor, on the substrate, which effectively reduces the chip area and material cost.

[0101] The present disclosure also provides an electronic device, including any power amplifier in the above embodiments. The electronic device includes but is not limited to a mobile phone, a tablet computer, a smart wearable device, etc.

[0102] It should be noted that the features disclosed in several method or device embodiments provided in the present disclosure can be arbitrarily combined without conflict to obtain new method embodiments or device embodiments.

[0103] The above is only a specific embodiment of the present disclosure, but the protection scope of the present disclosure is not limited thereto. Any person skilled in the art who is familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present disclosure, which should be included in the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure should be based on the protection scope of the claims.

Claims

1. A power amplifier, characterized in that: include: A main amplifier circuit and an auxiliary amplifier circuit, wherein the phase difference between the output signal of the main amplifier circuit and the output signal of the auxiliary amplifier circuit is 180 degrees; A combiner circuit, wherein the combiner circuit connects the main amplifier circuit and the auxiliary amplifier circuit; the combiner circuit is used to combine the voltage of the main amplifier circuit and the auxiliary amplifier circuit.

2. The power amplifier according to claim 1, characterized in that: The combiner circuit includes a balun.

3. The power amplifier according to claim 2, characterized in that: The balun is also used to adjust the combined impedance to the transmission impedance.

4. The power amplifier according to claim 2, characterized in that: The balun includes a primary coil, a secondary coil, a first capacitor and / or a second capacitor; wherein, The first end of the primary coil is connected to the output end of the main amplifier circuit, the second end of the primary coil is connected to the output end of the auxiliary amplifier circuit, and the first end of the secondary coil is connected to the load. The first capacitor is connected between the first end of the primary coil and the second end of the primary coil, The second capacitor is connected between the second end of the secondary coil and a ground terminal.

5. The power amplifier according to claim 2, characterized in that: The combined impedance of the main amplifier circuit and the auxiliary amplifier circuit is 4 to 10 ohms; And / or, the impedance transformation ratio of the balun is 1:4 to 1:

8.

6. The power amplifier according to claim 2, characterized in that: The power amplifier also includes a power supply, which is connected to the balun and feeds the main amplifier circuit and the auxiliary amplifier circuit through the balun.

7. The power amplifier according to claim 1, characterized in that: The main path amplification circuit comprises a main path amplifier; The auxiliary path amplification circuit comprises an auxiliary path amplifier; The main amplifier circuit further includes a first matching circuit, which is connected between the main amplifier and the combiner circuit; the first matching circuit includes a first resonant circuit, which is used to suppress harmonics of the output signal of the main amplifier; And / or, the auxiliary amplifier circuit also includes a second matching circuit, which is connected between the auxiliary amplifier and the combiner circuit; the second matching circuit includes a second resonant circuit, which is used to suppress harmonics of the output signal of the auxiliary amplifier.

8. The power amplifier according to claim 7, characterized in that: The second matching circuit is also used for phase shifting, so as to shift the phase of the output signal of the auxiliary amplifier.

9. The power amplifier according to claim 7, characterized in that: The second matching circuit includes at least one first-stage impedance matching circuit and at least one first filter inductor, and each of the first filter inductors is respectively connected to a capacitor in the first-stage impedance matching circuit so that the capacitor is grounded through the first filter inductor to form the second resonant circuit.

10. The power amplifier according to claim 9, characterized in that: The second matching circuit includes a secondary impedance matching circuit; the secondary impedance matching circuit includes a first inductor, a third capacitor, a second inductor and a fourth capacitor; wherein, The output end of the auxiliary amplifier is connected to the first end of the first inductor, the second end of the first inductor is connected to the first end of the third capacitor and the first end of the second inductor, and the second end of the second inductor and the first end of the fourth capacitor are connected to the first input end of the combiner circuit; The second end of the third capacitor is grounded through the first filter inductor; and / or the second end of the fourth capacitor is grounded through the first filter inductor.

11. The power amplifier according to claim 7, characterized in that: The second matching circuit also includes a fifth capacitor; the first end of the fifth capacitor is connected to the output end of the auxiliary amplifier, and the second end of the fifth capacitor is grounded; the fifth capacitor is also used as a charging and discharging capacitor of the auxiliary amplifier to enable the auxiliary amplifier to operate in Class E.

12. The power amplifier according to claim 11, characterized in that: The second matching circuit also includes a second filtering inductor, and the fifth capacitor is grounded through the second filtering inductor to form the second resonant circuit.

13. The power amplifier according to claim 7, characterized in that: The first resonant circuit includes a sixth capacitor and a third filtering inductor; The output end of the main amplifier is connected to the first end of the sixth capacitor and the second input end of the combiner circuit, the first end of the third filter inductor is connected to the second end of the sixth capacitor, and the second end of the third filter inductor is grounded.

14. The power amplifier according to claim 13, characterized in that: The sixth capacitor is also used as a charging and discharging capacitor of the main amplifier, so that the main amplifier works in Class E; or, The main amplifier operates in class AB.

15. The power amplifier according to claim 1, characterized in that: The main amplifier circuit also includes: A third matching circuit is connected between the power divider circuit and the main amplifier; The auxiliary amplifier circuit also includes: The fourth matching circuit is connected between the power divider circuit and the auxiliary amplifier; the phase difference between the output signal of the third matching circuit and the output signal of the fourth matching circuit is 90 degrees.

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