Low noise amplifier, radio frequency front end module and electronic device

Abstract

The application discloses a low-noise amplifier, a radio frequency front-end module and electronic equipment, wherein the low-noise amplifier comprises a radio frequency input end, a radio frequency output end and an amplification circuit connected between the radio frequency input end and the radio frequency output end, and the amplification circuit at least comprises a first amplification transistor; wherein the transconductance value of the first amplification transistor is greater than the transconductance value of at least one other transistor in the low-noise amplifier. The application improves the transconductance value of the amplification transistor for amplifying the radio frequency signal, so that the transconductance value is higher than that of at least one other transistor in the low-noise amplifier, thereby improving the gain of the low-noise amplifier and reducing the noise coefficient. Compared with improving the transconductance value of all transistors, the application only improves the transconductance value of part of the transistors, can reduce the process difficulty and production cost, and has stronger practicability.

Description

Technical Field

[0001] This application relates to the field of radio frequency technology, and in particular to a low-noise amplifier, a radio frequency front-end module, and an electronic device. Background Technology

[0002] Low-noise amplifiers are an important component of wireless transceiver systems. Their main function is to amplify the input radio frequency signal, and they have the characteristics of high gain and low noise.

[0003] Low-noise amplifiers are mainly composed of transistors, and the structural or electrical parameters of the transistors play a crucial role in the performance of the low-noise amplifier. Generally, the higher the transconductance of the transistor, the better the gain and noise performance of the low-noise amplifier, but correspondingly, its manufacturing difficulty and cost will also be higher.

[0004] In related technologies, all transistors in a low-noise amplifier have the same transconductance value. Increasing the transconductance value of the transistors to improve the performance of the low-noise amplifier would lead to a significant increase in cost; however, not increasing the transconductance value would hinder performance improvement. Therefore, how to improve the performance of a low-noise amplifier at low cost is a problem that urgently needs to be solved. Summary of the Invention

[0005] This application proposes a low-noise amplifier, an RF front-end module, and an electronic device, aiming to improve the performance of the low-noise amplifier at a low cost.

[0006] In a first aspect, embodiments of this application provide a low-noise amplifier, the low-noise amplifier including a radio frequency input terminal, a radio frequency output terminal, and an amplification circuit connected between the radio frequency input terminal and the radio frequency output terminal, the amplification circuit including at least a first amplification transistor;

[0007] Wherein, the transconductance value of the first amplifying transistor is greater than the transconductance value of at least one other transistor in the low-noise amplifier.

[0008] The aforementioned low-noise amplifier improves the gain and reduces the noise figure by specifically increasing the transconductance of the amplifying transistor used to amplify the radio frequency signal, making it higher than the transconductance of at least one other transistor in the low-noise amplifier. Furthermore, compared to related technologies that increase the transconductance of all transistors, this application only increases the transconductance of some transistors, which can reduce the process difficulty and production cost, and has greater practicality.

[0009] Secondly, embodiments of this application provide a low-noise amplifier, the low-noise amplifier including a radio frequency input terminal, a radio frequency output terminal, and an amplification circuit connected between the radio frequency input terminal and the radio frequency output terminal, the amplification circuit including at least a first transistor; wherein the transconductance value of the first amplification transistor is greater than or equal to 1.7 millisiemens / mm.

[0010] The aforementioned low-noise amplifier improves its performance by increasing the transconductance of at least one amplifying transistor in the amplification circuit to more than 1.7 millisiemens / mm, thereby increasing the gain of the low-noise amplifier and reducing its noise figure.

[0011] Thirdly, embodiments of this application provide a radio frequency front-end module, including a low-noise amplifier as described in the first or second aspect.

[0012] Fourthly, embodiments of this application provide an electronic device, including a low-noise amplifier as described in the first or second aspect, or including a radio frequency front-end module as described in the third aspect.

[0013] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit the disclosure of the embodiments of this application. Attached Figure Description

[0014] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0015] Figure 1 A schematic diagram of a low-noise amplifier provided in one embodiment of this application is shown.

[0016] Figure 2a A schematic diagram of a low-noise amplifier provided in another embodiment of this application is shown.

[0017] Figure 2b A schematic diagram of a low-noise amplifier provided in yet another embodiment of this application is shown.

[0018] Figure 3a A schematic diagram of a low-noise amplifier provided in yet another embodiment of this application is shown.

[0019] Figure 3b A schematic diagram of a low-noise amplifier provided in yet another embodiment of this application is shown.

[0020] Figure 4aA schematic diagram of a low-noise amplifier provided in yet another embodiment of this application is shown.

[0021] Figure 4b A schematic diagram of a low-noise amplifier provided in yet another embodiment of this application is shown.

[0022] Figure 4c A schematic diagram of a low-noise amplifier provided in yet another embodiment of this application is shown.

[0023] Figure 5a A schematic diagram of a low-noise amplifier provided in yet another embodiment of this application is shown.

[0024] Figure 5b A schematic diagram of a low-noise amplifier provided in yet another embodiment of this application is shown.

[0025] Figure 5c A schematic diagram of a low-noise amplifier provided in yet another embodiment of this application is shown.

[0026] Figure 5d A schematic diagram of a low-noise amplifier provided in yet another embodiment of this application is shown.

[0027] Figure 6 A schematic diagram of a low-noise amplifier provided in yet another embodiment of this application is shown.

[0028] Figure 7a A schematic diagram of a low-noise amplifier provided in yet another embodiment of this application is shown.

[0029] Figure 7b A schematic diagram of a low-noise amplifier provided in yet another embodiment of this application is shown.

[0030] Figure 8 A schematic diagram of a low-noise amplifier provided in yet another embodiment of this application is shown.

[0031] Figure 9 A schematic diagram of a low-noise amplifier provided in yet another embodiment of this application is shown.

[0032] Figure 10 A schematic diagram of a low-noise amplifier provided in yet another embodiment of this application is shown.

[0033] Figure 11 A schematic diagram of a radio frequency front-end module provided in an embodiment of this application is shown. Detailed Implementation

[0034] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of the present application, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without creative effort are within the scope of protection of the present application.

[0035] The terms "first," "second," etc., used in this application are used to distinguish different objects, not to describe a specific order. Unless otherwise specified, the term "multiple" refers to two or more. The term "and / or" refers to at least one of the listed multiple objects; for example, "A and / or B" can be any of the following three cases: including A but not B, including B but not A, or including both A and B.

[0036] Furthermore, the terms “comprising” and “having”, and any variations thereof, are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the steps or units listed, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such process, method, product, or apparatus.

[0037] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0038] In low-noise amplifiers (LNO) systems, the transconductance of the amplifying transistors is one of the key parameters determining their performance. A higher transconductance generally results in better amplifier gain and noise performance. Currently, in the fabrication of LNO amplifiers, all transistors utilize the same manufacturing process and have the same transconductance value. Increasing the transconductance value would lead to unnecessary cost increases; conversely, not increasing the transconductance value would hinder performance improvement. Therefore, how to improve the performance of LNO amplifiers at a low cost is a pressing issue that needs to be addressed.

[0039] To address the aforementioned issues, the inventors of this application, through extensive research, discovered that in low-noise amplifiers (LNAs), the transconductance values ​​of different transistors have varying degrees of impact on the LNA's performance. Specifically, the transconductance value of the transistor used to amplify radio frequency (RF) signals plays a crucial role in the LNA's gain, noise figure, and other performance indicators. However, even increasing the transconductance values ​​of other transistors has only a limited effect on improving these performance indicators. Therefore, this application proposes a novel LNA that specifically increases the transconductance value of the amplifying transistor used to amplify RF signals, making it higher than the transconductance value of at least one other transistor in the LNA. This improves the LNA's gain and reduces the noise figure. Furthermore, compared to related technologies that increase the transconductance value of all transistors, this application only increases the transconductance value of a subset of transistors, reducing manufacturing complexity and production costs, and thus offering greater practicality.

[0040] The technical solution of this application will be described below with reference to the accompanying drawings.

[0041] Please refer to Figure 1 , Figure 1 A schematic diagram of the circuit structure of a low-noise amplifier provided in this application is shown. Figure 1 As shown, the low-noise amplifier 100 includes an RF input terminal 110, an RF output terminal 120, and an amplifier circuit 130, wherein the amplifier circuit 130 is connected between the RF input terminal 110 and the RF output terminal 120, and the amplifier circuit 130 includes one or more amplifying transistors, such as a first amplifying transistor 131.

[0042] Optionally, the amplifier circuit 130 may contain one or more amplifying transistors 131.

[0043] As one implementation method, such as Figure 2a and Figure 2b As shown, the amplifier circuit 130 may include only the first amplifying transistor 131. Optionally, the first amplifying transistor 131 can be configured as follows: Figure 2a The common source method shown or through, as shown Figure 2b The common-gate configuration or other configuration shown is used to connect between the RF input terminal 110 and the RF output terminal 120.

[0044] For example, when the first amplifying transistor 131 is connected between the RF input terminal 110 and the RF output terminal 120 in a common-source configuration, the first terminal of the first amplifying transistor 131 is the input terminal of the amplification circuit 130, which can be connected to the RF input terminal 110 to receive the input RF signal; the second terminal of the first amplifying transistor 131 is the power supply terminal and the output terminal of the amplification circuit 130, which can be connected to the RF output terminal 120 to output the amplified RF signal, and connected to the power supply terminal of the low-noise amplifier 100 to receive the power supply voltage. The third terminal of the first amplifying transistor 131 is used for grounding.

[0045] As one implementation method, such as Figure 3a and Figure 3b As shown, the amplifier circuit 130 includes, in addition to the first amplifying transistor 131, at least one other amplifying transistor, such as the second amplifying transistor 132. Optionally, the first amplifying transistor 131 and the other amplifying transistors can be connected via, for example... Figure 3a The common source cascode configuration shown is used between the RF input terminal 110 and the RF output terminal 120. Alternatively, it can be connected via, as shown below... Figure 3b The distributed amplifier circuit shown is connected between the RF input terminal 110 and the RF output terminal 120 in the manner shown or in other ways. This application does not limit the circuit architecture adopted by the amplifier circuit 130.

[0046] For example, when the first amplifying transistor 131 and the second amplifying transistor 132 are connected between the RF input terminal 110 and the RF output terminal 120 in a common-source, common-gate configuration, the first terminal of the first amplifying transistor 131 is the input terminal of the amplifying circuit 130 and can be connected to the RF input terminal 110 to receive the input RF signal; the second terminal of the first amplifying transistor 131 is connected to the third terminal of the second amplifying transistor 132, and the third terminal of the first amplifying transistor 131 is used for grounding; the first terminal of the second amplifying transistor 132 can be used to receive the bias signal, and the second terminal of the second amplifying transistor 132 serves as the power supply terminal and output terminal of the amplifying circuit 130, and can be connected to the RF output terminal 120 to output the amplified RF signal, and connected to the power supply terminal of the low-noise amplifier 100 to receive the power supply voltage.

[0047] Among them, the first amplifying transistor 131 and the second amplifying transistor 132 can be field-effect transistors. Taking an N-channel field-effect transistor as an example, the first terminal of each transistor is the gate, the second terminal is the drain, and the third terminal is the source.

[0048] It should be noted that, unless otherwise specified, the term "connection" in this application can refer to a direct connection or an indirect connection. For example, the gate of the first amplifying transistor 131 can be directly connected to the RF input terminal 110, or it can be connected to the RF input terminal 110 through a capacitor. Similarly, the source of the first amplifying transistor 131 can be directly grounded, or it can be indirectly grounded through at least one component such as an inductor, capacitor, or resistor. Furthermore, the drain of the second amplifying transistor 132 can be directly connected to the power supply terminal Vdd, or it can be connected to the power supply terminal Vdd through a choke coil; the drain of the second amplifying transistor 132 can be directly connected to the RF output terminal 120, or it can be indirectly connected to the RF output terminal 120 through at least one component such as an inductor, capacitor, resistor, or switch.

[0049] It is understood that the low-noise amplifier 100 may include other circuit sections in addition to the amplification circuit 130, and these other circuit sections may include one or more transistors.

[0050] For example, the low-noise amplifier 100 may also include a bias circuit for providing bias to the amplifier circuit 130, and the bias circuit may include at least one bias transistor.

[0051] For example, the low-noise amplifier 100 may also include one or more switches, each of which may include one or more switching transistors.

[0052] Optionally, the number of RF input terminals 110 can be one or more. When there are multiple RF input terminals 110, and the RF signals input from multiple RF input terminals 110 need to be amplified by the same amplifier circuit 130, i.e., when the amplifier circuit 130 needs to be connected to multiple RF input terminals 110, the low-noise amplifier 100 may further include one or more input switches. Each input switch may correspond to one RF input terminal 110 and be connected between the amplifier circuit 130 and the corresponding RF input terminal 110. The low-noise amplifier 100 can switch the amplifier circuit 130 to amplify RF signals from different RF input terminals 110 by controlling the state (on or off) of each input switch. Accordingly, each input switch may include one or more switching transistors.

[0053] Optionally, the number of RF output terminals 120 can be one or more. When there are multiple RF output terminals 120, and different frequency band RF signals output by the same amplifier circuit 130 need to be output through different RF output terminals 120, i.e., when the amplifier circuit 130 needs to be connected to multiple RF output terminals 120, the low-noise amplifier 100 may further include one or more output switches. Each output switch may correspond to one RF output terminal 120 and be connected between the amplifier circuit 130 and the corresponding RF output terminal 120. The low-noise amplifier 100 can control the state (on or off) of each output switch to allow the amplifier circuit 130 to switch to different RF output terminals for output. Accordingly, each output switch may include one or more switching transistors.

[0054] For example, the low-noise amplifier 100 may also include a bypass circuit, which may include one or more bypass transistors. The bypass circuit is used to bypass the input radio frequency signal when the input power is high and further amplification is not required; that is, the input radio frequency signal is not amplified by the amplifier circuit 130.

[0055] It is understandable that, in addition to the input switches, output switches, and bypass circuits listed above, the low-noise amplifier 100 may also include other circuit parts with transistors, which will not be listed here.

[0056] In this embodiment, the transconductance of the first amplifying transistor 131 is greater than the transconductance of at least one other transistor in the low-noise amplifier 100. Since the first amplifying transistor 131 is a transistor in the amplifier circuit 130, it plays a key role in amplifying the radio frequency signal. By increasing the transconductance of the first amplifying transistor 131, the gain of the low-noise amplifier 100 can be improved and the noise figure of the low-noise amplifier 100 can be reduced, thereby improving the overall performance of the low-noise amplifier 100.

[0057] In one implementation, the transconductance of the first amplifying transistor 131 can be greater than the transconductance of at least one other amplifying transistor in the amplifying circuit 130, for example... Figure 3a In this embodiment, the transconductance of the first amplifying transistor 131 is greater than that of the second amplifying transistor 132. By selectively increasing the transconductance of some amplifying transistors in the amplifying circuit 130, the overall performance of the low-noise amplifier 100 can be improved while avoiding the cost increase caused by increasing the transconductance of all amplifying transistors, thereby achieving a low-cost performance improvement of the low-noise amplifier.

[0058] In one implementation, the transconductance of the first amplifying transistor 131 can be greater than the transconductance of at least one transistor in other circuit sections, for example, greater than the transconductance of at least one bias transistor; and / or, greater than the transconductance of at least one switching transistor; and / or, greater than the transconductance of at least one bypass transistor. In this embodiment, by selectively increasing the transconductance of the first amplifying transistor in the amplifying circuit 130 while not increasing the transconductance of at least one transistor in other circuit sections, the overall performance of the low-noise amplifier 100 can be improved while avoiding a significant increase in cost due to increasing the transconductance of all transistors, thereby achieving a low-cost performance improvement of the low-noise amplifier.

[0059] In one implementation, the transconductance of the first amplifying transistor 131 can be greater than the transconductance of at least one other amplifying transistor in the amplifying circuit 130, and also greater than the transconductance of at least one transistor in other circuit sections. In this embodiment, by selectively increasing the transconductance of the first amplifying transistor in the amplifying circuit 130, while not increasing the transconductance of at least one amplifying transistor in the amplifying circuit and at least one transistor in other circuit sections, the overall performance of the low-noise amplifier 100 can be improved while further reducing costs, thereby improving the performance of the low-noise amplifier at a lower cost.

[0060] In one implementation, some or all of the circuit elements in the low-noise amplifier of this application can be integrated into a chip. For example, the individual transistors in the low-noise amplifier, such as the amplifying transistor in the amplification circuit, the bias transistor in the bias circuit, the bypass transistor in the bypass circuit, and the switching transistor in the switch, can all be disposed in the chip.

[0061] In this embodiment, the transistors in the chip can be of the same type, such as field-effect transistors. Optionally, the transistors can be, but are not limited to, any of MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor), MESFET (Metal-Semiconductor Field-Effect Transistor), HEMT (High Electron Mobility Transistor), and pHEMT (Pseudo-morphological High Electron Mobility Transistor). Optionally, the substrate of the chip can be, but is not limited to, based on any of silicon (Si) substrate, silicon-on-insulator (SOI) substrate, gallium arsenide (GaAs) substrate, silicon carbide (SiC) substrate, and gallium nitride (GaN) substrate.

[0062] For example, the transistors in the low-noise amplifier 100 are integrated in a chip based on a Si substrate or an SOI substrate, and the transistor type is MOSFET or MESFET.

[0063] The following section uses MOSFETs based on Si or SOI substrates as examples to introduce methods for improving transistor transconductance.

[0064] As one implementation, the fabrication process of each transistor in the low-noise amplifier 100 of this application includes: fabricating a gate oxide layer on a Si substrate or an SOI substrate; fabricating a polysilicon layer on the gate oxide layer and etching the polysilicon layer to form a polysilicon gate; and doping the substrate of the source and drain regions and the polysilicon gate to form the source, drain and gate of the transistor.

[0065] The doping morphology of the polysilicon gate (hereinafter referred to as "gate doping") has a significant impact on the transconductance of the transistor. The inventors of this application have discovered that the higher the uniformity and thickness of the gate doping, the greater the transconductance of the transistor. Therefore, this application improves the fabrication process of the first amplifying transistor 131, making the gate doping uniformity of the first amplifying transistor 131 higher than that of at least one other transistor in the low-noise amplifier 100, or making the gate doping thickness of the first amplifying transistor 131 greater than that of at least one other transistor in the low-noise amplifier 100, or making both the gate doping thickness and gate doping uniformity of the first amplifying transistor 131 greater than those of at least one other transistor in the low-noise amplifier 100, thereby increasing the transconductance of the first amplifying transistor 131 and thus improving the gain and noise figure of the low-noise amplifier 100. Meanwhile, since the fabrication process of some transistors in the low-noise amplifier 100 remains unchanged, the implementation cost of this solution is low, enabling the performance of the low-noise amplifier 100 to be improved at a lower cost, and thus possessing strong practicality.

[0066] In related technologies, after forming the polysilicon gate, gate doping and source / drain region doping are usually performed simultaneously. On the one hand, since gate doping and source / drain region doping are performed in different regions and on different materials, simultaneous doping leads to low doping uniformity, which in turn reduces the transconductance of the transistor. On the other hand, since the source / drain regions require a relatively thin doping thickness, when the gate and source / drain regions are doped simultaneously, the gate doping thickness is often also very thin to meet the doping requirements of the source / drain regions, which further leads to a reduction in the transconductance of the transistor.

[0067] In this embodiment, as one implementation method, the source / drain doping and gate doping can be performed separately when fabricating the first amplifying transistor 131 and other transistors requiring increased transconductance. In other words, in this embodiment, at least the source / drain doping and gate doping of the first amplifying transistor 131 are performed sequentially, while the source / drain doping and gate doping of at least one other transistor (a transistor that does not require increased transconductance) in the low-noise amplifier 100 are performed simultaneously. This allows the gate doping process to be independently controlled, eliminating the need to reduce the gate doping thickness to meet the doping requirements of the source / drain regions, thereby increasing the gate doping thickness to improve the transconductance of the first amplifying transistor 131. Furthermore, performing gate doping separately also improves the uniformity of gate doping, reasonably balances doping thickness and doping punch-through, and improves the transconductance of the first amplifying transistor 131 while ensuring its reliability.

[0068] In another implementation, when fabricating the first amplifying transistor 131 and other transistors that require increased transconductance, the gate doping number can be increased to increase the gate doping thickness, thereby increasing the transconductance of the transistors. In other words, in this embodiment, at least the gate doping number of the first amplifying transistor 131 is greater than the gate doping number of at least one other transistor in the low-noise amplifier 100 (the transistor that does not require increased transconductance).

[0069] In another embodiment, when fabricating the first amplifying transistor 131 and other transistors requiring increased transconductance, the number of gate doping operations can be increased to increase the gate doping thickness, and at least one gate doping operation can be performed separately from the source / drain region doping, thereby further improving the transconductance of the transistors. In other words, in this embodiment, at least the number of gate doping operations of the first amplifying transistor 131 is greater than the number of gate doping operations of at least one other transistor in the low-noise amplifier 100 (the transistor that does not require increased transconductance); and at least the source / drain region doping and gate doping of the first amplifying transistor 131 are performed sequentially, while the source / drain region doping and gate doping of at least one other transistor in the low-noise amplifier 100 are performed simultaneously.

[0070] For example, for the first amplifying transistor 131 and other transistors requiring improved transconductance, source / drain region doping and the first gate doping can be performed simultaneously. Then, the source / drain regions are masked and at least one more gate doping is performed. This allows for increasing the gate doping thickness and uniformity without increasing the source / drain region doping thickness, reasonably balancing doping thickness and doping punch-through, and improving the transconductance of the first amplifying transistor 131 while ensuring its reliability. Furthermore, in this embodiment, the source / drain region doping and the first gate doping process of the first amplifying transistor 131 and other transistors requiring improved transconductance can be performed simultaneously with the source / drain region doping and gate doping of other transistors that do not require improved transconductance. This eliminates the need to change the source / drain region doping process flow and mask, helping to reduce process difficulty and save manufacturing costs. In addition, since the first amplifying transistor 131 and other transistors requiring improved transconductance already have a certain gate doping thickness after source / drain region doping, the gate doping time can be shortened in subsequent gate doping processes, improving overall fabrication efficiency.

[0071] In some embodiments of this application, the transconductance of the first amplifying transistor 131 is greater than or equal to 1.7 mS / mm, while the low-noise amplifier 100 also includes at least one other transistor with a transconductance less than or equal to 1.65 millisiemens / mm. For example, the bias circuit of the low-noise amplifier 100 may include at least one bias transistor with a transconductance less than or equal to 1.65 millisiemens / mm; and / or, the switch of the low-noise amplifier 100 may include at least one bias transistor with a transconductance less than or equal to 1.65 millisiemens / mm; and / or, the bypass circuit of the low-noise amplifier 100 may include at least one bypass transistor with a transconductance less than or equal to 1.65 millisiemens / mm; and / or, the amplifying circuit 130 of the low-noise amplifier 100 may include at least one amplifying transistor with a transconductance less than or equal to 1.65 millisiemens / mm.

[0072] In related technologies, the transconductance of transistors is typically below 1.65 mS / mm (millisiemens per millimeter). In this application embodiment, by improving the fabrication process of the first amplifying transistor, the transconductance value of the first amplifying transistor 131 can be increased to greater than or equal to 1.7 mS / mm, thereby increasing the gain coefficient of the low-noise amplifier 100 and reducing the noise figure of the low-noise amplifier 100.

[0073] Furthermore, the first amplifying transistor 131 can be integrated into a chip with an SOI substrate, and the transconductance of the first amplifying transistor 131 can be increased to greater than or equal to 1.8 mS / mm, thereby further improving the gain and noise figure of the low-noise amplifier.

[0074] In one implementation, the transconductance of the first amplifying transistor 131 is less than 2.0 mS / mm. By controlling the transconductance of the first amplifying transistor 131 to a range of less than 2.0 mS / mm, it is possible to better balance the doping thickness and doping punch-through, and while increasing the doping thickness, control the degree of doping punch-through, thereby improving the reliability of the first amplifying transistor 131.

[0075] In at least one embodiment, such as Figures 4a to 5d As shown, the low-noise amplifier 100 also includes a bias circuit 140 and a first capacitor C1. The bias circuit 140 provides a bias signal to the amplifier circuit 130, enabling the amplifier circuit 130 to operate and amplify the input radio frequency signal. The bias circuit 140 is connected at least to the first terminal of the first amplifying transistor 131, thereby providing bias to the first amplifying transistor 131. The first capacitor C1 is connected between the first terminal of the first amplifying transistor 131 and the radio frequency input terminal 110 to prevent the bias signal input to the first terminal of the first amplifying transistor 131 from leaking to the radio frequency input terminal 110.

[0076] The bias circuit 140 includes one or more bias transistors, at least one of which has a transconductance value lower than that of the first amplifying transistor 131. Optionally, the at least one bias transistor may be fabricated using a different process than that of the first amplifying transistor 131, thereby achieving a lower transconductance value than that of the first amplifying transistor 131. For example, the gate doping number of the at least one bias transistor may be less than that of the first amplifying transistor 131; and / or, the gate doping thickness of the at least one bias transistor may be less than that of the first amplifying transistor 131; and / or, the gate doping uniformity of the at least one bias transistor may be less than that of the first amplifying transistor 131.

[0077] Optionally, the amplifier circuit 130 can be biased by current or by voltage. Correspondingly, the bias circuit 140 can provide bias current or bias voltage for the amplifier circuit 130.

[0078] It should be noted that when the bias circuit 140 includes multiple bias transistors, depending on the biasing method, the transconductance value of the first amplifying transistor 131 can be greater than the transconductance values ​​of all bias transistors; it can also be greater than the transconductance values ​​of some bias transistors. In other words, some bias transistors in the bias circuit 140 may have the same transconductance value as the first amplifying transistor 131.

[0079] In one implementation, when the amplifier circuit 130 is current biased, at least one bias transistor in the bias circuit 140 is connected to at least one amplifying transistor in the amplifier circuit to form a current mirror, thereby enabling the amplifying transistor to mirror the output current of the bias transistor.

[0080] Specifically, such as Figure 5a As shown in Figure 5b, the bias circuit 140 includes a first bias transistor 141, which is connected to the first amplifying transistor 131 to form a current mirror. Specifically, the gate of the first bias transistor 141 is connected to the gate of the first amplifying transistor 131, and the sources of both the first bias transistor 141 and the first amplifying transistor 131 are grounded. The first bias transistor 141 and the first amplifying transistor 131 can be identical in at least one aspect, such as transconductance, gate doping thickness, gate doping uniformity, and gate doping order, thereby improving the matching degree between the first amplifying transistor 131 and the first bias transistor 141 and making the current mirror ratio more accurate. Specifically, the transconductance value of the first bias transistor 141 is the same as that of the first amplifying transistor 131; and / or, the gate doping thickness of the first bias transistor 141 is the same as that of the first amplifying transistor 131; and / or, the gate doping uniformity of the first bias transistor 141 is the same as that of the first amplifying transistor 131; and / or, the number of gate doping operations of the first bias transistor 141 is the same as that of the first amplifying transistor 131.

[0081] For example, the first bias transistor 141 can be fabricated using the same process as the first amplifying transistor 131, thereby having the same transconductance value, which can maximize the matching degree between the first amplifying transistor 131 and the first bias transistor 141.

[0082] In this embodiment, the transconductance values ​​of the first bias transistor 141 and the first amplification transistor 131 can be greater than the transconductance value of at least one other transistor in the low noise amplifier, thereby enabling the performance of the low noise amplifier 100 to be further improved at a lower cost.

[0083] In one implementation, when the amplifier circuit 130 uses a voltage biasing method, the bias transistors in the bias circuit 140 can generate a bias voltage through cascading. In this case, the connection relationship between the bias transistors and the amplifying transistors differs from that of the current mirror. Therefore, the transconductance value of at least one bias transistor can be less than the transconductance value of the first amplifying transistor 131, thereby reducing the cost of the low-noise amplifier. Optionally, the transconductance value of the first amplifying transistor 131 can be greater than the transconductance value of each bias transistor, or it can be greater than the transconductance values ​​of some of the bias transistors; this application does not limit this.

[0084] Specifically, the bias circuit 140 may include at least two voltage divider elements connected in series, for example, between the power supply terminal and the ground terminal, so that a voltage is generated at the connection node of every two adjacent voltage divider elements. A first amplifying transistor is connected to the connection node of two adjacent voltage divider elements to obtain a bias voltage. In this embodiment, at least some of the voltage divider elements are third bias transistors, and the transconductance value of the third bias transistor can be less than the transconductance value of the first amplifying transistor 131, thereby reducing the manufacturing cost of the third bias transistor.

[0085] Optionally, each voltage divider element is implemented through a third bias transistor; or, some voltage divider elements are third bias transistors, and other voltage divider elements can be resistors, which is not limited in this application.

[0086] For example, when the voltage divider element uses a third bias transistor, taking an N-channel transistor as an example, the gate and drain of the third bias transistor can be shorted. In this case, the third bias transistor is equivalent to a diode, so that there is a certain voltage drop between the source and drain when the third bias transistor is turned on, thereby better performing voltage division.

[0087] For example, the bias circuit 140 may include at least two third bias transistors connected in series and having at least two connection nodes, with the gate of the first amplifying transistor 131 connected to the connection node between two adjacent third bias transistors. At least some of the third bias transistors have a transconductance value less than that of the first amplifying transistor. For example, the transconductance value of each third bias transistor is less than that of the first amplifying transistor, thereby further reducing the cost of the low-noise amplifier 100.

[0088] In one implementation, the bias circuit 140 also includes a second bias transistor, which does not form a current mirror with the first amplifying transistor 131, and the transconductance value of the second bias transistor 142 can be less than or equal to the transconductance value of the first amplifying transistor 131.

[0089] The following section uses a common-source, common-gate amplifier architecture as an example to introduce the amplifier circuit and bias circuit of the low-noise amplifier 100.

[0090] In at least one embodiment, such as Figure 4b and Figure 4cAs shown, the amplifier circuit 130 includes a first amplifying transistor 131 and a second amplifying transistor 132. The gate of the first amplifying transistor 131 is connected to the RF input terminal 110 to receive the input RF signal. The source of the first amplifying transistor 131 is grounded. The drain of the first amplifying transistor 131 is connected to the source of the second amplifying transistor 132. The drain of the second amplifying transistor 132 serves as the power supply terminal and output terminal of the amplifier circuit 130. It is connected to the power supply terminal Vdd of the low noise amplifier 100 on one hand and to the RF output terminal 120 on the other hand to output the amplified RF signal.

[0091] In one implementation, the transconductance of the second amplifying transistor 132 can also be less than or equal to the transconductance of the first amplifying transistor 131 to reduce the manufacturing cost of the second amplifying transistor 132. Since the first amplifying transistor 131 is a common-source transistor and the second amplifying transistor 132 is a common-gate transistor, the inventors of this application have discovered through long-term research that in a common-source and common-gate amplifier circuit structure, the transconductance of the common-source transistor plays a decisive role in the gain and noise figure of the amplifier circuit, and its influence is far greater than that of the common-gate transistor. Therefore, this implementation, by increasing the transconductance of the first amplifying transistor 131 without increasing the transconductance of the second amplifying transistor 132, can effectively improve the performance of the low-noise amplifier at a lower cost.

[0092] In another implementation, the transconductance value of the second amplifying transistor 132 can also be the same as that of the first amplifying transistor 131, and both transconductance values ​​are greater than the transconductance value of at least one other transistor in the low-noise amplifier 100. This implementation can improve the performance of the low-noise amplifier to a greater extent by simultaneously increasing the transconductance values ​​of the common-source transistor and the common-gate transistor.

[0093] As one implementation method, such as Figure 4b and Figure 5b As shown, the second amplifying transistor 132 in the amplifying circuit 130 can be connected to the power supply terminal Vdd. Using the power supply voltage as a bias signal, the bias circuit 140 can be connected to the first amplifying transistor 131 but not to the second amplifying transistor 132. The bias circuit 140 provides a bias signal to the first amplifying transistor 131.

[0094] Specifically, the bias circuit 140 may include a first bias transistor 141, which is connected to the first amplifying transistor 131 to form a current mirror. Specifically, the gate of the first bias transistor 141 is connected to the gate of the first amplifying transistor 131, and the sources of both the first bias transistor 141 and the first amplifying transistor 131 are grounded. The first bias transistor 141 and the first amplifying transistor 131 can be identical in at least one aspect, such as transconductance, gate doping thickness, gate doping uniformity, and gate doping order, thereby improving the matching degree between the first amplifying transistor 131 and the first bias transistor 141 and making the current mirror ratio more accurate. Specifically, the transconductance value of the first bias transistor 141 is the same as that of the first amplifying transistor 131; and / or, the gate doping thickness of the first bias transistor 141 is the same as that of the first amplifying transistor 131; and / or, the gate doping uniformity of the first bias transistor 141 is the same as that of the first amplifying transistor 131; and / or, the number of gate doping operations of the first bias transistor 141 is the same as that of the first amplifying transistor 131.

[0095] For example, the first bias transistor 141 can be fabricated using the same process as the first amplifying transistor 131, thereby having the same transconductance value, which can maximize the matching degree between the first amplifying transistor 131 and the first bias transistor 141.

[0096] In this embodiment, the transconductance values ​​of the first bias transistor 141 and the first amplification transistor 131 can be greater than the transconductance value of at least one other transistor in the low noise amplifier, thereby enabling the performance of the low noise amplifier 100 to be further improved at a lower cost.

[0097] As one implementation method, such as Figure 4c and Figure 5c As shown, the bias circuit 140 can be connected to the first amplifying transistor 131 and the second amplifying transistor 132 in the amplifier circuit 130, and together provide bias current to the first amplifying transistor 131 and the second amplifying transistor 132 in the amplifier circuit 130.

[0098] Specifically, the bias circuit 140 includes a first bias transistor 141 and a second bias transistor 142, wherein the first terminal of the first bias transistor 141 is connected to the first terminal of the first amplifying transistor 131, and the first terminal of the second bias transistor 142 is connected to the first terminal of the second amplifying transistor 132.

[0099] For example, the gate of the first bias transistor 141 is connected to the gate of the first amplifying transistor 131, and both the source of the first bias transistor 141 and the source of the first amplifying transistor 131 are grounded. The gate of the second bias transistor 142 is connected to the gate of the second amplifying transistor 132, and the source of the second bias transistor 142 is connected to the drain and gate of the first bias transistor 141. The first bias transistor 141, the second bias transistor 142, the first amplifying transistor 131, and the second amplifying transistor 132 constitute a cascode current mirror.

[0100] The first bias transistor 141 and the first amplifying transistor 131 can be the same in at least one aspect, such as transconductance, gate doping thickness, gate doping uniformity, and gate doping number. The second bias transistor 142 and the second amplifying transistor 132 can be the same in at least one aspect, such as transconductance, gate doping thickness, gate doping uniformity, and gate doping number. This improves the matching degree between the first amplifying transistor 131 and the first bias transistor 141, as well as between the second amplifying transistor 132 and the second bias transistor 142, making the current mirror ratio more accurate.

[0101] Specifically, the transconductance value of the first bias transistor 141 is the same as that of the first amplifying transistor 131; and / or, the gate doping thickness of the first bias transistor 141 is the same as that of the first amplifying transistor 131; and / or, the gate doping uniformity of the first bias transistor 141 is the same as that of the first amplifying transistor 131; and / or, the number of gate doping operations of the first bias transistor 141 is the same as that of the first amplifying transistor 131.

[0102] Specifically, the transconductance value of the second bias transistor 142 is the same as that of the second amplifying transistor 132; and / or, the gate doping thickness of the second bias transistor 142 is the same as that of the second amplifying transistor 132; and / or, the gate doping uniformity of the second bias transistor 142 is the same as that of the second amplifying transistor 132; and / or, the number of gate doping operations of the second bias transistor 142 is the same as that of the second amplifying transistor 132.

[0103] For example, the transconductance value of the first bias transistor 141 is the same as that of the first amplifying transistor 131, and the transconductance value of the second bias transistor 142 is the same as that of the second amplifying transistor 132. For instance, the first bias transistor 141 can be fabricated using the same process as the first amplifying transistor 131, thus having the same transconductance value; the second bias transistor 142 can be fabricated using the same process as the second amplifying transistor 133, thus having the same transconductance value. This maximizes the matching degree of the cascode current mirror and improves the bias current accuracy of the low-noise amplifier.

[0104] In this embodiment, the transconductance values ​​of the first bias transistor 141 and the first amplifying transistor 131 can be greater than the transconductance values ​​of the second bias transistor 142 and the second amplifying transistor 132; alternatively, the first bias transistor 141, the first amplifying transistor 131, the second bias transistor 142, and the second amplifying transistor 132 can have the same transconductance value, which is greater than the transconductance value of at least one other transistor (such as a bypass transistor or a switching transistor) in the low-noise amplifier. This allows for further improvement of the performance of the low-noise amplifier 100 at a lower cost.

[0105] As one implementation, when the amplifier circuit 130 adopts a voltage biasing method, the bias transistors in the bias circuit 140 can generate a bias voltage by cascading. At this time, the connection relationship between the bias transistors and the amplifier transistors is different from the connection method of the current mirror. Therefore, the transconductance value of at least one bias transistor can be less than the transconductance value of the first amplifier transistor 131, so as to reduce the cost of the low noise amplifier.

[0106] Taking amplifier circuit 130 with a common-source, common-gate amplifier structure as an example, such as Figure 5d As shown, the bias circuit 140 includes at least three voltage divider elements, which are connected in series and have at least two connection nodes; the first terminal of the first amplifying transistor 131 and the first terminal of the second amplifying transistor 132 are respectively connected to different connection nodes; wherein, the at least three voltage divider elements include at least two third bias transistors 143 and at least one voltage divider resistor; or, each voltage divider element is a third bias transistor 143, that is, the at least three voltage divider elements are at least three third bias transistors 143.

[0107] In this embodiment, since the third bias transistor 143 does not form a current mirror with the first amplifying transistor 131 or the second amplifying transistor 132, the transconductance value of the third bias transistor 143 can be reduced or not increased, so that the transconductance value of the third bias transistor is less than the transconductance value of the first amplifying transistor 131, thereby further reducing the cost of the low-noise amplifier 100 without affecting the bias accuracy.

[0108] In one implementation, the bias circuit 140 may include at least one pull-down switch 144. One end of the pull-down switch 144 is connected to the output terminal of the bias circuit 140, and the other end is grounded. When the amplifier circuit 130 is not working, for example when the low noise amplifier 100 is in bypass mode, the pull-down switch 144 can be turned on to pull the bias signal output by the bias circuit 140 down to ground.

[0109] In this embodiment, the transconductance of the pull-down switch 144 can be less than the transconductance of the first amplifying transistor 131 to reduce the cost of the low-noise amplifier.

[0110] It should be noted that regardless of whether the amplifier circuit 130 adopts a voltage biasing method or a current biasing method, a pull-down switch 144 can be set, that is, the pull-down switch 144 can be applied to all biasing circuits mentioned in this application.

[0111] In at least one embodiment, such as Figure 6 As shown, the low-noise amplifier 100 may further include a bypass circuit 150 connected between the RF input terminal 110 and the RF output terminal 120. When the low-noise amplifier 100 operates in bypass mode, the RF signal input from the RF input terminal 110 will pass through the bypass circuit 150 and be output without passing through the amplification circuit 130. Specifically, the bypass circuit 150 includes at least one bypass transistor 151, and the transconductance value of the bypass transistor 151 is less than or equal to the transconductance value of the first amplification transistor 131.

[0112] In this embodiment, the low-noise amplifier 100 may operate in an amplification mode and a bypass mode. When the power of the radio frequency signal input from the radio frequency input terminal 110 is low, the low-noise amplifier 100 may operate in amplification mode, amplifying the weak received radio frequency signal before outputting it. When the power of the radio frequency signal input from the radio frequency input terminal 110 is high, the low-noise amplifier 100 may operate in bypass mode, thereby directly outputting the received radio frequency signal or outputting it after attenuation.

[0113] In one implementation, the bypass circuit 150 may include one or more bypass transistors 151 connected in series. Each bypass transistor 151 is connected in series between the RF input terminal 110 and the RF output terminal 120. When each bypass transistor 151 is turned on, the RF signal input from the RF input terminal 110 will be transmitted to the RF output terminal 120 through each turned-on bypass transistor 151 without being amplified by the amplifier circuit 130.

[0114] Understandably, in bypass mode, due to the large power of the input RF signal, the low noise amplifier 100 has lower gain requirements and a relatively higher tolerance for noise figure. Therefore, configuring the bypass transistor 151 as a transistor without transconductance enhancement, i.e., the transconductance value of the bypass transistor 151 is less than the transconductance value of the first amplifying transistor 131, can reduce the cost of the low noise amplifier 100 without affecting the performance of the low noise amplifier.

[0115] In one implementation, the bypass circuit 150 may further include one or more power attenuation elements for attenuating the power of the radio frequency signal passing through the bypass circuit 150. Optionally, at least one power attenuation element may be a resistor, and at least one resistor may be connected in series with the bypass transistor 151. Exemplarily, when the bypass circuit 150 includes multiple resistors, at least some of the resistors may be connected in series with the bypass transistor 151 to form a series branch, and at least some of the resistors may have one end connected to the series branch formed by the resistor and the bypass transistor 151, and the other end grounded to form a parallel branch.

[0116] In at least one embodiment, the low-noise amplifier 100 further includes one or more switching transistors, wherein the transconductance of at least one switching transistor is less than the transconductance of the first amplifying transistor. Optionally, the one or more switching transistors may include at least one first switching transistor 161 and / or at least one second switching transistor 162.

[0117] As one implementation method, such as Figure 7a As shown, the low-noise amplifier 100 includes a bypass circuit 150, and at least one first switching transistor 161 is connected in series between the output terminal of the bypass circuit 150 and the RF output terminal 120. When the low-noise amplifier 100 operates in bypass mode, the first switching transistor 161 is turned off to improve the isolation between the amplifier circuit 130 and the bypass circuit 150, preventing RF signals from leaking from the bypass circuit 150 to the amplifier circuit 130. When the low-noise amplifier 100 operates in amplification mode, the first switching transistor 161 is turned on, allowing the RF signal amplified by the amplifier circuit 130 to be transmitted to the RF output terminal 120 through the turned-on first switching transistor 161. The transconductance value of the first switching transistor 161 can be less than or equal to the transconductance value of the first amplification transistor 131.

[0118] As one implementation method, such as Figure 7bAs shown, the low-noise amplifier 100 includes a bypass circuit 150, and at least one second switching transistor 162 is connected in series between the input terminal of the bypass circuit 150 and the RF input terminal 110. When the low-noise amplifier 100 operates in bypass mode, the second switching transistor 162 is turned off to improve the isolation between the amplifier circuit 130 and the bypass circuit 150, preventing RF signals from leaking from the bypass circuit 150 to the amplifier circuit 130. When the low-noise amplifier 100 operates in amplification mode, the second switching transistor 162 is turned on, allowing the RF signal input from the RF input terminal 110 to be transmitted to the amplifier circuit 130 through the turned-on second switching transistor 162, where it is amplified. The transconductance value of the second switching transistor 162 can be less than or equal to the transconductance value of the first amplifying transistor 131.

[0119] In one implementation, the low-noise 100 includes a bypass circuit 150, at least one first switching transistor 161, and at least one second switching transistor 162. The at least one first switching transistor 161 is connected in series between the output terminal of the bypass circuit 150 and the RF output terminal 120, and the at least one second switching transistor 162 is connected in series between the input terminal of the bypass circuit 150 and the RF input terminal 110, which can further improve the isolation between the amplifier circuit 130 and the bypass circuit 150.

[0120] The transconductance of the first switching transistor 161 can be less than or equal to the transconductance of the first amplifying transistor 131, and the transconductance of the second switching transistor 162 can be less than or equal to the transconductance of the first amplifying transistor 131.

[0121] Understandably, in bypass mode, the radio frequency signal is primarily transmitted through the bypass circuit 150 without passing through the amplifier circuit 130 and the first switching transistor 161 and / or the second switching transistor 162 connected in series with the amplifier circuit 130. The transconductance values ​​of the first switching transistor 161 and / or the second switching transistor 162 have almost no impact on the performance of the low-noise amplifier 100 in bypass mode. Even in amplification mode, the radio frequency signal passes through the conducting first switching transistor 161 and / or the second switching transistor 162, but since the first switching transistor 161 and / or the second switching transistor 162 do not amplify the signal, their transconductance values ​​have very little impact on the performance of the low-noise amplifier 100 in amplification mode.

[0122] Therefore, by configuring the first switching transistor 161 and the second switching transistor 162 as transistors without transconductance enhancement, the transconductance values ​​of the first switching transistor 161 and the second switching transistor 162 are less than the transconductance value of the first amplifying transistor 131, which can reduce the cost of the low-noise amplifier 100 without affecting the performance of the low-noise amplifier.

[0123] Of course, one or both of the first switching transistor 161 and the second switching transistor 162 can be configured as transistors with the same transconductance value as the first amplifying transistor 131, while cost control can be achieved by configuring at least one other transistor in the low-noise amplifier 100 (such as a bias transistor, a bypass transistor, or at least one of other switching transistors) as transistors with smaller transconductance values.

[0124] As one implementation method, such as Figure 8 As shown, the low-noise amplifier 100 includes M radio frequency input terminals 110 and M first switch branches 163 corresponding to the M radio frequency input terminals. Each radio frequency input terminal is connected to the amplifier circuit through the corresponding first switch branch 163. Each first switch branch 163 includes at least one switching transistor, where M is a positive integer and M≥2.

[0125] The amplifier circuit 130 can amplify multiple radio frequency (RF) signals of different frequency bands. These signals are input from different RF input terminals 110, for example, each of the M RF input terminals 110 is used to input a RF signal of a corresponding frequency band. By configuring M first switch branches 163 in a one-to-one correspondence between the M RF input terminals 110 and the amplifier circuit 130, the RF signals input to the amplifier circuit 130 can be switched by controlling the switching states (e.g., on or off) of the M first switch branches 163. This allows the amplifier circuit 130 to amplify different RF signals at different times, thereby avoiding crosstalk between different RF signals.

[0126] In this embodiment, each first switching branch 163 includes at least one switching transistor, so the M first switching branches 163 include at least M switching transistors in total, wherein the transconductance value of at least one switching transistor may be less than the transconductance value of the first amplifying transistor 131.

[0127] It is understandable that, although in amplification mode, the RF signal passes through the switching transistor in the first switching branch 163 before being input to the amplification circuit 130, the switching transistor does not amplify the signal. Therefore, the transconductance value of the switching transistor in the first switching branch 163 has very little impact on the performance of the low-noise amplifier. Based on this, this embodiment, by configuring at least one switching transistor as a transistor without transconductance enhancement, making its transconductance value smaller than that of the first amplifying transistor 131, can reduce the cost of the low-noise amplifier 100 without affecting its performance.

[0128] Optionally, the transconductance values ​​of some switching transistors in each of the first switching branches 163 can be configured to be lower than the transconductance value of the first amplifying transistor 131, so as to reasonably control the cost of the low noise amplifier 100 without affecting the performance of the low noise amplifier; or the transconductance values ​​of all switching transistors in each of the first switching branches 163 can be configured to be lower than the transconductance value of the first amplifying transistor 131, so as to further reduce the cost of the low noise amplifier 100 without affecting the performance of the low noise amplifier.

[0129] For example, such as Figure 9 As shown, the amplifier circuit 130 may include multiple amplification branches, which are connected one-to-one to multiple radio frequency input terminals 110. For example, the amplifier circuit 130 may include M amplification branches, each of which corresponds to a switch branch 163 and a radio frequency input terminal 110. The M amplification branches are connected to the corresponding M radio frequency input terminals 110 (specifically 111 to 11M) through the corresponding switch branches 163 (specifically 1631 to 163M).

[0130] Optionally, each amplification branch includes one or more amplification transistors. When each amplification branch includes multiple amplification transistors, some transistors can be multiplexed across multiple amplification branches to reduce the number of transistors required in the amplifier circuit 130, which is beneficial for the miniaturization design of low-noise amplifiers. Taking a common-source, common-gate amplification structure as an example, such as... Figure 9 As shown, each of the M amplification branches can have a non-multiplexed common-source amplifier transistor (i.e., the first amplification transistor 131), and the M amplification branches can share a common-gate amplifier transistor (i.e., the second amplification transistor 132). In the common-source common-gate amplification structure, the common-source amplifier transistor has the greatest impact on the performance of the entire amplification circuit. By setting multiple amplification branches to share the common-gate amplifier transistor instead of the common-source amplifier transistor, the number of transistors in the low-noise amplifier 100 can be reduced while maintaining high performance, thereby reducing the area of ​​the low-noise amplifier 100 and lowering the cost.

[0131] In one implementation, when the amplifier circuit 130 includes a plurality of first amplifying transistors 131, the first amplifying transistors 131 in all amplifying branches can be configured to use the same fabrication process and have the same high transconductance value, so as to maximize the performance of the low noise amplifier 100.

[0132] As another implementation, when the amplifier circuit 130 includes a plurality of first amplifying transistors 131, the first amplifying transistors 131 in some amplifying branches can be configured to have higher transconductance values, while the first amplifying transistors 131 in other amplifying branches can have lower transconductance values, according to the frequency band and bandwidth of the radio frequency signals corresponding to different amplifying branches, or according to the different performance requirements of different amplifying branches. This improves the performance of some amplifying branches in the low-noise amplifier 100 at a lower cost.

[0133] As one implementation method, such as Figure 8 and Figure 9 As shown, the low-noise amplifier 100 includes N radio frequency output terminals 120 and N second switch branches 164 corresponding to the N radio frequency output terminals 120. Each radio frequency output terminal 120 is connected to the output terminal of the amplifier circuit through the corresponding second switch branch 164. Each second switch branch 164 includes at least one switching transistor, where N is a positive integer and N≥2.

[0134] In this embodiment, by controlling the switching states (e.g., on or off) of the N second switch branches 164, different frequency bands of RF signals output by the amplifier circuit 130 can be selectively output to different RF output terminals 120. It should be noted that the number of RF output terminals 120 may be less than the number of RF input terminals 110; that is, the relationship between the RF output terminals 120 and the frequency bands of the RF signals may not be one-to-one. One RF output terminal 120 can be used to output RF signals of one frequency band or multiple frequency bands.

[0135] In this embodiment, each second switching branch 164 includes at least one switching transistor, so the N second switching branches 164 include at least N switching transistors in total, wherein the transconductance value of at least one switching transistor may be less than the transconductance value of the first amplifying transistor 131.

[0136] It is understandable that, although in amplification mode, the amplified RF signal passes through the switching transistor in the conducting second switching branch 164 before being input to the RF output terminal 120, the switching transistor does not amplify the signal. Therefore, the transconductance value of the switching transistor in the second switching branch 164 has very little impact on the performance of the low-noise amplifier. Based on this, this embodiment, by configuring at least one switching transistor as a transistor without transconductance enhancement, making its transconductance value smaller than that of the first amplifying transistor 131, can reduce the cost of the low-noise amplifier 100 without affecting its performance.

[0137] Optionally, the transconductance values ​​of some switching transistors in each of the second switching branches 164 can be configured to be lower than the transconductance value of the first amplifying transistor 131, so as to reasonably control the cost of the low noise amplifier 100 without affecting the performance of the low noise amplifier; alternatively, the transconductance values ​​of all switching transistors in each of the second switching branches 164 can be configured to be lower than the transconductance value of the first amplifying transistor 131, so as to further reduce the cost of the low noise amplifier 100 without affecting the performance of the low noise amplifier.

[0138] In at least one embodiment, the low-noise amplifier further includes a power supply terminal and a ground terminal, and at least one of a first inductor L1, a second inductor L2, an input matching circuit 170, an output matching circuit 180, and a power discharge circuit 190.

[0139] For example, such as Figure 2b or Figure 3a As shown, the first inductor L1 is connected in series between the third terminal of the first amplifying transistor 131 and the ground terminal; the first inductor L1 can be used to increase the real part of the input impedance and improve the stability of the low-noise amplifier 100.

[0140] For example, such as Figure 2a or Figure 3a As shown, the second inductor L2 is connected in series between the power supply terminal and the output terminal of the amplifier circuit; the second inductor L2 can act as a choke to isolate signal interference between the DC power supply signal and the radio frequency signal, thereby improving the stability and reliability of the low-noise amplifier 100.

[0141] For example, such as Figure 10 As shown, the input matching circuit is connected to the RF input terminal and can be used to match the input impedance of the RF input terminal with the output impedance of the preamplifier circuit to reduce the loss of the RF signal during transmission from the preamplifier circuit to the RF input terminal. Optionally, the input matching circuit may include at least one third inductor L3, which is connected in series between the preamplifier circuit and the RF input terminal. For example, as... Figure 10As shown, when the low-noise amplifier 100 has multiple radio frequency input terminals 110, each radio frequency input terminal 110 is connected in series with one or more third inductors L3 to the corresponding pre-amplifier circuit. The inductance value of the third inductor L3 connected to each radio frequency input terminal 110 may be different depending on the frequency band of the input radio frequency signal.

[0142] The pre-amplifier circuit can be any circuit element between the antenna and the low-noise amplifier, such as a filter or a switching chip in the RF front-end module. When the low-noise amplifier 100 has multiple RF input terminals 110, different RF input terminals 110 can be connected to the output terminals of different filters or to different ports of the switching chip.

[0143] Optionally, the third inductor L3 in the input matching circuit can be integrated into the chip along with each transistor, or it can be disposed on the substrate and implemented through metal wiring of the substrate wiring layer or by using SMD devices. This application does not limit this.

[0144] For example, such as Figure 10 As shown, the output matching circuit 180 is connected between the output terminal of the amplifier circuit and the RF output terminal. The output matching circuit 180 can be used to match the output impedance of the amplifier circuit with the input impedance of the subsequent circuit to reduce the loss of the amplified RF signal during transmission from the RF output terminal 120 to the subsequent circuit. Optionally, the output matching circuit 180 may include at least one capacitor and / or inductor, and the specific circuit structure is not limited in this application.

[0145] For example, such as Figure 10 As shown, the low-noise amplifier 100 includes a power bleeder branch 190. One end of the power bleeder branch 190 is connected to the RF input terminal 110, and the other end is grounded. The power bleeder branch 190 includes a resistor R1 and a switch S1 connected in series. When the input power of the RF signal is too high, the low-noise amplifier 100 can control the switch S1 in the power bleeder branch 190 to be turned on, so that part of the input power is bleed to ground through the turned-on switch S1 and resistor R1, thereby reducing the input power of the amplifier circuit 130 and preventing the amplifier circuit 130 from experiencing gain compression due to excessive input power, thereby improving the linearity of the amplifier circuit 130.

[0146] Optionally, the number of power discharge branches 190 can be one or more. When the low-noise amplifier 100 includes multiple RF input terminals 110, the number of power discharge branches 190 can be less than or equal to the number of RF input terminals 110. Power discharge branches 190 can be provided only between some RF input terminals 110 and the ground terminal, or power discharge branches 190 can be provided between each RF input terminal 110 and the ground terminal. This application does not limit this.

[0147] In one implementation, the switch S1 in the power discharge branch 190 includes one or more switching transistors, the transconductance of which may be less than or equal to the transconductance of the first amplifying transistor. For example, the transconductance of the switching transistor being less than that of the first amplifying transistor can further reduce the cost of the low-noise amplifier 100 without affecting its performance.

[0148] In at least one embodiment, the low-noise amplifier is integrated within a chip having a silicon-on-insulator (SiI) substrate. Using SiI as the substrate not only helps to increase the transconductance of the first amplifying transistor, but also reduces the parasitic capacitance of each transistor and lowers the power consumption of the transistors, thus significantly improving the performance of the low-noise amplifier 100.

[0149] A second aspect of this application also provides a low-noise amplifier 100, which includes an RF input terminal 110, an RF output terminal 120, and an amplification circuit 130 connected between the RF input terminal and the RF output terminal. The amplification circuit 130 includes at least a first transistor, wherein the transconductance of the first amplification transistor is greater than or equal to 1.7 millisiemens / mm.

[0150] In one implementation, the transconductance of the first amplifying transistor is greater than or equal to 1.8 millisiemens / mm.

[0151] In one implementation, the low-noise amplifier also includes a bypass circuit 150, which includes at least one bypass transistor with a transconductance of less than or equal to 1.65 millisiemens / mm.

[0152] In one implementation, the low-noise amplifier also includes a bias circuit 140, which includes at least one bias transistor with a transconductance of less than or equal to 1.65 millisiemens / mm.

[0153] In one implementation, the low-noise amplifier also includes a switching circuit, which includes at least one switching transistor with a transconductance of less than or equal to 1.65 millisiemens / mm.

[0154] It should be noted that the specific circuit structure of the low-noise amplifier 100 in this embodiment, the relationship between the transconductance values ​​of different transistors, etc., are all based on the relevant description of the low-noise amplifier 100 provided in the first aspect, and will not be repeated here.

[0155] The embodiments of this application improve the overall performance of the low-noise amplifier 100 by increasing the transconductance of the first amplifying transistor in the low-noise amplifier 100 to 1.7 millisiemens / mm or more.

[0156] A third aspect of this application also provides a radio frequency front-end module 200, including the low-noise amplifier 100 shown in any of the above embodiments.

[0157] In some implementations, the RF front-end module may also include at least one RF switch, RF power amplifier, filter, duplexer, etc., which can be integrated into a single module to improve integration and performance and reduce size.

[0158] The RF front-end module can be selected to send RF signals to the antenna port or receive RF signals from the antenna port, thereby enabling amplification, filtering, and other processing of RF analog signals.

[0159] By enhancing the transconductance of at least some of the amplifying transistors in the low-noise amplifier 100 of the RF front-end module 200, the performance of the low-noise amplifier 100 can be significantly improved.

[0160] A fourth aspect of this application also provides an electronic device, including a low-noise amplifier 100 or a radio frequency front-end module 200 as shown in any of the above embodiments.

[0161] The electronic device can be a mobile phone, tablet computer, vehicle terminal or other communication device. Of course, it can also be other communication devices with communication functions. The embodiments of this application do not limit the specific types of electronic devices.

[0162] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A low-noise amplifier, characterized in that, The low-noise amplifier includes an RF input terminal, an RF output terminal, and an amplification circuit connected between the RF input terminal and the RF output terminal. The amplification circuit includes at least a first amplification transistor and a second amplification transistor. A first terminal of the first amplification transistor is connected to the RF input terminal, a second terminal of the first amplification transistor is connected to a third terminal of the second amplification transistor, and the third terminal of the first amplification transistor is grounded. A first terminal of the second amplification transistor is connected to the bias circuit or power supply terminal of the low-noise amplifier, and a second terminal of the second amplification transistor is connected to both the RF output terminal and the power supply terminal. The transconductance of the first amplifying transistor is greater than that of the second amplifying transistor.

2. The low-noise amplifier according to claim 1, characterized in that, The gate doping uniformity of the first amplifying transistor is higher than that of at least one other transistor in the low-noise amplifier; and / or The gate doping thickness of the first amplifying transistor is greater than the gate doping thickness of at least one other transistor in the low-noise amplifier.

3. The low-noise amplifier according to claim 1, characterized in that, The source / drain doping and gate doping of the first amplifying transistor are performed sequentially; the source / drain doping and gate doping of at least one other transistor in the low-noise amplifier are performed simultaneously; and / or The gate doping number of the first amplifying transistor is greater than the gate doping number of at least one other transistor in the low-noise amplifier.

4. The low-noise amplifier according to claim 1, characterized in that, The first amplifying transistor has a transconductance greater than or equal to 1.7 millisiemens / mm; the low-noise amplifier also includes at least one other transistor with a transconductance less than or equal to 1.65 millisiemens / mm.

5. The low-noise amplifier according to claim 4, characterized in that, The first amplifying transistor is integrated within a chip with an SOI substrate, and the transconductance of the first amplifying transistor is greater than or equal to 1.8 millisiemens / mm.

6. The low-noise amplifier according to claim 4, characterized in that, The transconductance of the first amplifying transistor is less than 2.0 millisiemens / mm.

7. The low-noise amplifier according to claim 1, characterized in that, The amplification circuit further includes a bias circuit and a first capacitor. The bias circuit is connected to the first terminal of the first amplification transistor, and the first terminal of the first amplification transistor is connected to the radio frequency input terminal through the first capacitor.

8. The low-noise amplifier according to claim 7, characterized in that, The bias circuit includes one or more bias transistors, wherein the transconductance of the first amplifying transistor is greater than the transconductance of at least one of the bias transistors.

9. The low-noise amplifier according to claim 7, characterized in that, The bias circuit includes a first bias transistor, which is connected to the first amplifying transistor to form a current mirror; Wherein, the transconductance value of the first bias transistor is the same as the transconductance value of the first amplifying transistor; and / or, the gate doping thickness of the first bias transistor is the same as the gate doping thickness of the first amplifying transistor; and / or, the gate doping uniformity of the first bias transistor is the same as the gate doping uniformity of the first amplifying transistor; and / or, the number of gate doping cycles of the first bias transistor is the same as the number of gate doping cycles of the first amplifying transistor.

10. The low-noise amplifier according to claim 7, characterized in that, The bias circuit includes a second bias transistor, which does not form a current mirror with the first amplifying transistor, and the transconductance of the second bias transistor is less than or equal to the transconductance of the first amplifying transistor.

11. The low-noise amplifier according to claim 9, characterized in that, The bias circuit includes at least two voltage divider elements connected in series, and the first amplifying transistor is connected to the connection node of two adjacent voltage divider elements. In this embodiment, at least a portion of the voltage divider elements are third bias transistors, and the transconductance of the third bias transistor is less than the transconductance of the first amplifying transistor.

12. The low-noise amplifier according to any one of claims 7-11, characterized in that, The second terminal of the first amplifying transistor is the power supply terminal and the output terminal of the amplifying circuit, and the third terminal of the first amplifying transistor is used for grounding.

13. The low-noise amplifier according to any one of claims 7-11, characterized in that, The bias circuit further includes a second bias transistor, the first terminal of which is connected to the first terminal of the second amplifying transistor, and the transconductance of the second bias transistor is the same as that of the second amplifying transistor.

14. The low-noise amplifier according to any one of claims 7-11, characterized in that, The bias circuit includes at least three voltage divider elements connected in series and having at least two connection nodes; the first terminal of the first amplifying transistor and the first terminal of the second amplifying transistor are respectively connected to different connection nodes. The at least three voltage divider elements include at least two third bias transistors and at least one voltage divider resistor; or, the at least three voltage divider elements are at least three third bias transistors.

15. The low-noise amplifier according to claim 1, characterized in that, The low-noise amplifier further includes a bypass circuit connected between the RF input terminal and the RF output terminal, and the bypass circuit includes at least one bypass transistor, the transconductance of which is less than or equal to the transconductance of the first amplifying transistor.

16. The low-noise amplifier according to claim 1, characterized in that, The low-noise amplifier further includes one or more switching transistors, wherein at least one of the switching transistors has a transconductance value less than that of the first amplifying transistor.

17. The low-noise amplifier according to claim 16, characterized in that, The low-noise amplifier includes M radio frequency input terminals and M switching branches corresponding to the M radio frequency input terminals. Each radio frequency input terminal is connected to the amplifier circuit through the corresponding switching branch. Each switching branch includes at least one switching transistor. M is a positive integer and M≥2.

18. The low-noise amplifier according to any one of claims 1-11 and 15-17, characterized in that, The transistors in the low-noise amplifier are field-effect transistors, with each transistor having a first terminal as the gate, a second terminal as the drain, and a third terminal as the source.

19. The low-noise amplifier according to claim 18, characterized in that, The low-noise amplifier is integrated into a chip, which has a silicon-on-insulator substrate.

20. A low-noise amplifier, characterized in that, The low-noise amplifier includes an RF input terminal, an RF output terminal, and an amplification circuit connected between the RF input terminal and the RF output terminal. The amplification circuit includes at least a first amplifying transistor and a second amplifying transistor. The second terminal of the first amplifying transistor is connected to the third terminal of the second amplifying transistor, and the third terminal of the first amplifying transistor is grounded. The first terminal of the second amplifying transistor is connected to the bias circuit or power supply terminal of the low-noise amplifier. The second terminal of the second amplifying transistor is connected to the RF output terminal and the power supply terminal. The transconductance of the first amplifying transistor is greater than or equal to 1.7 millisiemens / mm.

21. The low-noise amplifier according to claim 20, characterized in that, The transconductance of the first amplifying transistor is greater than or equal to 1.8 millisiemens / mm.

22. The low-noise amplifier according to claim 20, characterized in that, The transconductance of the first amplifying transistor is less than 2.0 millisiemens / mm.

23. The low-noise amplifier according to claim 20, characterized in that, The low-noise amplifier also includes a bypass circuit, which includes at least one bypass transistor with a transconductance of less than or equal to 1.65 millisiemens / mm. and / or The low-noise amplifier further includes a bias circuit comprising at least one bias transistor with a transconductance less than or equal to 1.65 millisiemens / mm; and / or The low-noise amplifier also includes a switching circuit, which includes at least one switching transistor with a transconductance of less than or equal to 1.65 millisiemens / mm.

24. A radio frequency front-end module, characterized in that, Including the low-noise amplifier as described in any one of claims 1-23.

25. An electronic device, characterized in that, Includes the low-noise amplifier as described in any one of claims 1-23 or the radio frequency front-end module as described in claim 24.

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