Low-noise amplifier, radio frequency front-end module and electronic equipment

Abstract

The invention discloses a low noise amplifier, a radio frequency front end module and electronic equipment, 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 transconductance value of the amplification transistor used for amplifying the radio-frequency signal is increased in a targeted mode to be higher than the transconductance value of at least one other transistor in the low-noise amplifier, so that the gain of the low-noise amplifier is increased, the noise coefficient is reduced, and compared with increasing of the transconductance values of all the transistors, the transconductance value of the amplification transistor is increased. The transconductance values of only part of transistors are increased, the process difficulty and the production cost can be reduced, and higher practicability is achieved.

Description

Technical Field

[0001] The present 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 Art

[0002] The low noise amplifier is one of the important components in the wireless transceiver system. Its main function is to amplify the input RF signal. It has the characteristics of high gain and low noise.

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

[0004] In the related art, all transistors of a low noise amplifier have the same transconductance value. If the transconductance value of the transistor is increased for the performance of the low noise amplifier, the cost will increase significantly; and if the transconductance value is not increased, it will not be conducive to the performance improvement of the low noise amplifier. Therefore, how to improve the performance of the low noise amplifier at a low cost is a problem that needs to be solved urgently. Summary of the invention

[0005] The present application proposes a low noise amplifier, a radio frequency 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, an embodiment of the present application provides a low noise amplifier, the low noise amplifier comprising a radio frequency input terminal, a radio frequency output terminal and an amplifier circuit connected between the radio frequency input terminal and the radio frequency output terminal, the amplifier circuit comprising at least a first amplifier transistor;

[0007] 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 above-mentioned low-noise amplifier improves the transconductance value of the amplifying transistor used to amplify the radio frequency signal in a targeted manner so that it is higher than the transconductance value of at least one other transistor in the low-noise amplifier, thereby improving the gain of the low-noise amplifier and reducing the noise factor. Moreover, compared with the related art in which the transconductance value of all transistors is improved, the present application only improves the transconductance value of some transistors, which can reduce the process difficulty and production cost and has stronger practicality.

[0009] In a second aspect, an embodiment of the present application provides a low-noise amplifier, which includes a radio frequency input terminal, a radio frequency output terminal, and an amplifier circuit connected between the radio frequency input terminal and the radio frequency output terminal, wherein the amplifier circuit includes at least a first transistor; wherein the transconductance value of the first amplifier transistor is greater than or equal to 1.7 millisiemens / mm.

[0010] The above-mentioned low noise amplifier can increase the gain of the low noise amplifier and reduce the noise factor by increasing the transconductance value of at least one amplifying transistor in the amplifying circuit to above 1.7 millisiemens / mm, thereby improving the performance of the low noise amplifier.

[0011] In a third aspect, an embodiment of the present application provides a radio frequency front-end module, comprising a low noise amplifier as described in the first aspect or the second aspect.

[0012] In a fourth aspect, an embodiment of the present application provides an electronic device, comprising a low noise amplifier as described in the first aspect or the second aspect, or comprising 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 merely exemplary and explanatory and cannot limit the disclosure of the embodiments of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those skilled in the art, other drawings can be obtained based on these drawings without creative work.

[0015] Figure 1 A schematic diagram of a low noise amplifier provided in an embodiment of the present application is shown.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

[0031] Fig. 9 A schematic diagram of a low noise amplifier provided in yet another embodiment of the present application is shown.

[0032] Fig.10 A schematic diagram of a low noise amplifier provided in yet another embodiment of the present application is shown.

[0033] Fig.11 A schematic diagram of a radio frequency front-end module provided in an embodiment of the present application is shown. DETAILED DESCRIPTION

[0034] In order 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 in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present application.

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

[0036] In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to these processes, methods, products or devices.

[0037] Reference to "embodiments" herein means that a particular feature, structure, or characteristic described in conjunction with the embodiments may be included in at least one embodiment of the present application. The appearance of the phrase in various locations in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0038] In a low-noise amplifier, the transconductance of the amplifying transistor is one of the key parameters that determine its performance. The larger the transconductance, the better the gain and noise performance of the amplifier. In the related art, when preparing a low-noise amplifier, all transistors use the same manufacturing process and have the same transconductance value. If the transconductance value is increased, it will lead to unnecessary cost increase; and if the transconductance value is not increased, it will not be conducive to the performance improvement of the low-noise amplifier. Therefore, how to improve the performance of the low-noise amplifier at a low cost is a problem that needs to be solved urgently.

[0039] In order to solve the above problems, the inventors of the present application have found after long-term research that in a low-noise amplifier, the transconductance values ​​of different transistors have different degrees of improvement on the performance of the low-noise amplifier. Among them, the transconductance value of the transistor used to amplify the radio frequency signal plays a key role in the performance indicators such as the gain and noise factor of the low-noise amplifier. Even if the transconductance values ​​of other transistors are improved, the degree of improvement on the performance indicators such as the gain and noise factor of the low-noise amplifier is very limited. Therefore, the present application proposes a new low-noise amplifier, which improves the gain of the low-noise amplifier and reduces the noise factor by specifically improving the transconductance value of the amplifying transistor used to amplify the radio frequency signal to make it higher than the transconductance value of at least one other transistor in the low-noise amplifier. Moreover, compared with the related art of improving the transconductance values ​​of all transistors, the present application only improves the transconductance values ​​of some transistors, which can reduce the process difficulty and production cost and has stronger practicality.

[0040] The technical solution of the present application will be described below in conjunction with the accompanying drawings.

[0041] Please refer to Figure 1 , Figure 1 FIG. 1 shows a circuit structure diagram of a low noise amplifier provided by the present application. Figure 1 As shown, the low noise amplifier 100 includes a radio frequency input terminal 110, a radio frequency output terminal 120 and an amplifier circuit 130, wherein the amplifier circuit 130 is connected between the radio frequency input terminal 110 and the radio frequency output terminal 120, and the amplifier circuit 130 includes one or more amplifier transistors, for example, a first amplifier transistor 131.

[0042] Optionally, the number of the amplifying transistors 131 in the amplifying circuit 130 may be one or more.

[0043] As an implementation method, Figure 2a and Figure 2b As shown, the amplifier circuit 130 may include only the first amplifier transistor 131. Optionally, the first amplifier transistor 131 may be configured as follows: Figure 2a The common source method shown or by Figure 2b The common gate method or other methods shown are connected between the RF input terminal 110 and the RF output terminal 120 .

[0044] Exemplarily, when the first amplifying transistor 131 is connected between the RF input terminal 110 and the RF output terminal 120 in a common source manner, the first terminal of the first amplifying transistor 131 is the input terminal of the amplifying 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 output terminal of the amplifying 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 an implementation method, Figure 3a and Figure 3b As shown, the amplifier circuit 130 includes at least one other amplifier transistor in addition to the first amplifier transistor 131, such as the second amplifier transistor 132. Optionally, the first amplifier transistor 131 and the other amplifier transistors can be connected as shown in FIG. Figure 3a The common source and common gate method shown is connected between the RF input terminal 110 and the RF output terminal 120, and can also be connected by Figure 3b The distributed amplifier circuit is connected between the RF input terminal 110 and the RF output terminal 120 in the manner shown or in other manners. The present application does not limit the circuit architecture adopted by the amplifier circuit 130 .

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

[0047] The first amplifying transistor 131 and the second amplifying transistor 132 may be field effect transistors. Taking an N-type field effect transistor as an example, the first end of each transistor is a gate, the second end is a drain, and the third end is a source.

[0048] It should be noted that, unless otherwise specified, the term "connection" in this application can mean a direct connection or an indirect connection. For example, the gate of the first amplifier 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. For another example, the source of the first amplifier transistor 131 can be directly grounded, or it can be indirectly grounded through at least one component such as an inductor, a capacitor, or a resistor. For another example, the drain of the second amplifier 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; the drain of the second amplifier 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, a capacitor, a resistor, or a switch.

[0049] It is understandable that, in addition to the amplifying circuit 130 , the low noise amplifier 100 may also include other circuit parts, and the other circuit parts may also include one or more transistors.

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

[0051] For example, the low noise amplifier 100 may further include one or more switches, and each switch may include one or more switching transistors.

[0052] Optionally, the number of RF input terminals 110 may be one or more. When the number of RF input terminals 110 is multiple, and the RF signals input from the multiple RF input terminals 110 need to be amplified by the same amplifier circuit 130, that is, the amplifier circuit 130 needs to be connected to multiple RF input terminals 110, the low noise amplifier 100 may also include one or more input switches, each of which 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 may control the state (on or off) of each input switch to switch the amplifier circuit 130 to amplify the RF signals from different RF input terminals 110. Accordingly, each input switch may include one or more switching transistors.

[0053] Optionally, the number of RF output terminals 120 may be one or more. When the number of RF output terminals 120 is multiple, and the RF signals of different frequency bands output by the same amplifying circuit 130 need to be output through different RF output terminals 120, that is, when the amplifying circuit 130 needs to be connected to multiple RF output terminals 120, the low noise amplifier 100 may also include one or more output switches, each of which may correspond to one RF output terminal 120 and be connected between the amplifying circuit 130 and the corresponding RF output terminal 120. The low noise amplifier 100 may control the state of each output switch (on or off) so that the amplifying circuit 130 switches 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 further include a bypass circuit, which may include one or more bypass transistors. The bypass circuit is used to bypass the input RF signal when the input power is large and no further amplification is required, that is, the input RF signal is not amplified by the amplifier circuit 130.

[0055] It is understandable that, in addition to the input switch, output switch, and bypass circuit listed above, the low noise amplifier 100 may also include other circuit parts having transistors, which are not listed one by one here.

[0056] In the embodiment of the present application, the transconductance value of the first amplifier transistor 131 is greater than the transconductance value of at least one other transistor in the low-noise amplifier 100. Since the first amplifier 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 value of the first amplifier transistor 131, the gain of the low-noise amplifier 100 can be improved and the noise coefficient of the low-noise amplifier 100 can be reduced, thereby improving the overall performance of the low-noise amplifier 100.

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

[0058] As an implementation, the transconductance value of the first amplifying transistor 131 may be greater than the transconductance value of at least one transistor in other circuit parts, for example, greater than the transconductance value of at least one bias transistor; and / or, greater than the transconductance value of at least one switch transistor; and / or, greater than the transconductance value of at least one bypass transistor. In this implementation, by selectively increasing the transconductance value of the first amplifying transistor in the amplifying circuit 130, while not increasing the transconductance value of at least one transistor in other circuit parts, the overall performance of the low noise amplifier 100 can be improved while avoiding the sharp increase in cost caused by increasing the transconductance of all transistors, thereby achieving low-cost improvement of the performance of the low noise amplifier.

[0059] As an implementation, the transconductance value of the first amplifier transistor 131 may be greater than the transconductance value of at least one other amplifier transistor in the amplifier circuit 130, and greater than the transconductance value of at least one transistor in other circuit parts. In this implementation, by selectively improving the transconductance value of the first amplifier transistor in the amplifier circuit 130, while not improving the transconductance value of at least one amplifier transistor in the amplifier circuit and at least one transistor in other circuit parts, the cost can be further reduced while improving the overall performance of the low-noise amplifier 100, thereby improving the performance of the low-noise amplifier at a lower cost.

[0060] As an implementation, some or all of the circuit elements in the low noise amplifier of the present application can be integrated into a chip. For example, each transistor in the low noise amplifier, such as an amplifying transistor in an amplifying circuit, a biasing transistor in a biasing circuit, a bypass transistor in a bypass circuit, a switching transistor in a switch, etc., can be arranged in a chip.

[0061] In this embodiment, each transistor in the chip can be a transistor of the same type, for example, all are field effect transistors. Optionally, each transistor can be, but is not limited to, any one of MOSFET (metal oxide semiconductor field effect transistor), MESFET (metal semiconductor field effect transistor), HEMT (high electron mobility transistor), pHEMT (pseudomorphic high electron mobility transistor). Optionally, the substrate of the chip can be, but is not limited to, any one of a silicon (Si) substrate, a silicon on insulator (SOI) substrate, a gallium arsenide (GaAs) substrate, a silicon carbide (SiC) substrate, and a gallium nitride (GaN) substrate.

[0062] Exemplarily, 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 is an example of a method for improving the transconductance value of a transistor using a MOSFET based on a Si substrate or an SOI substrate.

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

[0065] Among them, the doping (hereinafter referred to as "gate doping") morphology of the polysilicon gate has a great influence on the transconductance of the transistor. The inventors of the present application have found through research that the higher the uniformity of the gate doping and the greater the doping thickness, the greater the transconductance value of the transistor. Therefore, the embodiment of the present application improves the preparation process of the first amplifier transistor 131, so that the gate doping uniformity of the first amplifier transistor 131 is higher than the gate doping uniformity of at least one other transistor in the low noise amplifier 100, or the gate doping thickness of the first amplifier transistor 131 is greater than the gate doping thickness of at least one other transistor in the low noise amplifier 100, or the gate doping thickness and gate doping uniformity of the first amplifier transistor 131 are greater than at least one other transistor in the low noise amplifier 100, thereby improving the transconductance of the first amplifier transistor 131, and then improving the gain and noise coefficient of the low noise amplifier 100. At the same time, since the preparation process of some transistors in the low noise amplifier 100 has not been changed, the implementation cost of this solution is low, and the performance of the low noise amplifier 100 can be improved at a low cost, which has strong practicality.

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

[0067] In the embodiment of the present application, as an implementation method, when preparing the first amplifier transistor 131 and other transistors that need to improve transconductance, the source and drain region doping and the gate doping can be carried out separately. In other words, in this implementation method, the source and drain region doping and gate doping of at least the first amplifier transistor 131 are carried out successively, while the source and drain region doping and gate doping of at least one other transistor in the low-noise amplifier 100 (a transistor that does not need to improve transconductance) are carried out simultaneously. In this way, the gate doping process can be controlled independently, and there is no need to reduce the gate doping thickness in order to take into account the doping requirements of the source and drain regions, so that the gate doping thickness can be increased to improve the transconductance of the first amplifier transistor 131. In addition, the gate doping is carried out separately, which can also improve the uniformity of the gate doping, reasonably balance the doping thickness and doping penetration, and improve the transconductance of the first amplifier transistor 131 while ensuring the reliability of the first amplifier transistor 131.

[0068] As another implementation, when preparing the first amplifying transistor 131 and other transistors that need to improve transconductance, the gate doping times can be increased to increase the gate doping thickness, thereby improving the transconductance of the transistor. In other words, in this implementation, at least the gate doping times of the first amplifying transistor 131 is greater than the gate doping times of at least one other transistor (transistor that does not need to improve transconductance) in the low noise amplifier 100.

[0069] As another embodiment, when preparing the first amplifier transistor 131 and other transistors that need to improve transconductance, the number of gate doping can be increased to increase the gate doping thickness, and at least one gate doping can be performed separately from the source and drain region doping, thereby further improving the transconductance of the transistor. In other words, in this embodiment, at least the number of gate doping of the first amplifier transistor 131 is greater than the number of gate doping of at least one other transistor in the low-noise amplifier 100 (a transistor that does not need to improve transconductance); and at least the source and drain region doping and gate doping of the first amplifier transistor 131 are performed successively, while the source and 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 amplifier transistor 131 and other transistors that need to improve transconductance, source and drain region doping and first gate doping can be performed simultaneously, and then the source and drain regions are covered and at least one gate doping is performed, so that the gate doping thickness and uniformity can be increased without increasing the source and drain region doping thickness, and the doping thickness and doping punch-through can be reasonably balanced, thereby improving the transconductance of the first amplifier transistor 131 while ensuring the reliability of the first amplifier transistor 131. Moreover, in this embodiment, the source and drain region doping and first gate doping process of the transistors that need to improve transconductance, such as the first amplifier transistor 131, can be performed simultaneously with the source and drain region doping and gate doping of other transistors that do not need to improve transconductance, without changing the process flow and mask of source and drain region doping, which helps to reduce process difficulty and save manufacturing costs; in addition, since the first amplifier transistor 131 and other transistors that need to improve transconductance already have a certain gate doping thickness after the source and drain region doping, the gate doping time can be shortened in the subsequent gate doping process, thereby improving the overall preparation efficiency.

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

[0072] In the related art, the transconductance of a transistor is usually lower than 1.65 mS / mm (milliSiemens / millimeter). The embodiment of the present application improves the preparation process of the first amplifier transistor, and can increase the transconductance value of the first amplifier transistor 131 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 coefficient of the low-noise amplifier 100.

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

[0074] As an implementation mode, the transconductance value of the first amplifier transistor 131 is less than 2.0 mS / mm. By controlling the transconductance value of the first amplifier transistor 131 within a range of less than 2.0 mS / mm, it is possible to better balance the doping thickness and doping penetration, control the degree of doping penetration while increasing the doping thickness, and improve the reliability of the first amplifier transistor 131.

[0075] In at least one embodiment, 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 is used to provide a bias signal for the amplifier circuit 130 so that the amplifier circuit 130 can be in a working state, thereby amplifying the input radio frequency signal. The bias circuit 140 is at least connected to the first end of the first amplifier transistor 131, thereby providing a bias for the first amplifier transistor 131. The first capacitor C1 is connected between the first end of the first amplifier transistor 131 and the radio frequency input terminal 110 to prevent the bias signal input to the first end of the first amplifier transistor 131 from leaking to the radio frequency input terminal 110.

[0076] The bias circuit 140 includes one or more bias transistors, and the transconductance value of at least one bias transistor is smaller than the transconductance value of the first amplifying transistor 131. Optionally, at least one bias transistor may be manufactured using a different process from that of the first amplifying transistor 131, thereby achieving a transconductance value lower than that of the first amplifying transistor 131. Exemplarily, the gate doping times of at least one bias transistor may be less than the gate doping times of the first amplifying transistor 131; and / or, the gate doping thickness of at least one bias transistor is smaller than the gate doping thickness of the first amplifying transistor 131; and / or, the gate doping uniformity of at least one bias transistor is smaller than the gate doping uniformity of the first amplifying transistor 131.

[0077] Optionally, the amplifier circuit 130 may adopt a current bias method or a voltage bias method. Accordingly, the bias circuit 140 may provide a bias current or a bias voltage for the amplifier circuit 130 .

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

[0079] As an implementation, when the amplifier circuit 130 adopts a current biasing method, at least one bias transistor in the bias circuit 140 is connected to at least one amplifier transistor in the amplifier circuit to form a current mirror, so that the amplifier transistor can mirror the output current of the bias transistor.

[0080] Specifically, Figure 5a As shown in FIG. 5b, the bias circuit 140 includes a first bias transistor 141, and the first bias transistor 141 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 source of the first bias transistor 141 and the source of the first amplifying transistor 131 are both grounded. The first bias transistor 141 and the first amplifying transistor 131 may be the same in at least one aspect such as transconductance value, gate doping thickness, gate doping uniformity, and gate doping times, 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 the transconductance value of the first amplifying transistor 131; and / or, the gate doping thickness of the first bias transistor 141 is the same as the gate doping thickness of the first amplifying transistor 131; and / or, the gate doping uniformity of the first bias transistor 141 is the same as the gate doping uniformity of the first amplifying transistor 131; and / or, the gate doping times of the first bias transistor 141 is the same as the gate doping times of the first amplifying transistor 131.

[0081] Exemplarily, the first bias transistor 141 may be manufactured 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 amplifying transistor 131 may be greater than the transconductance value of at least one other transistor in the low noise amplifier, thereby further improving the performance of the low noise amplifier 100 at a lower cost.

[0083] As an implementation mode, when the amplifier circuit 130 adopts a voltage biasing mode, the bias transistors in the bias circuit 140 can generate a bias voltage by cascading. At this time, the connection relationship between the bias transistor and the amplifier transistor is different from the connection mode of the current mirror, and the transconductance value of at least one bias transistor can be smaller than the transconductance value of the first amplifier transistor 131 to reduce the cost of the low noise amplifier. Optionally, the transconductance value of the first amplifier transistor 131 can be greater than the transconductance value of each bias transistor, and can also be greater than the transconductance value of some bias transistors, which is not limited in the present application.

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

[0085] Optionally, each voltage-dividing element is implemented by a third biasing transistor; or, some of the voltage-dividing elements are third biasing transistors, and other some of the voltage-dividing elements may be resistors, which is not limited in the present application.

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

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

[0088] As an implementation, the bias circuit 140 further includes a second bias transistor, which does not form a current mirror with the first amplifying transistor 141 , and a transconductance value of the second bias transistor 141 may be less than or equal to a transconductance value of the first amplifying transistor 131 .

[0089] The following uses the common-source and 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, Figure 4b and Figure 4cAs shown, the amplifier circuit 130 includes a first amplifier transistor 131 and a second amplifier transistor 132, wherein the gate of the first amplifier transistor 131 is connected to the RF input terminal 110 to receive the input RF signal, the source of the first amplifier transistor 131 is grounded, the drain of the first amplifier transistor 131 is connected to the source of the second amplifier transistor 132, and the drain of the second amplifier transistor 132 serves as the power supply terminal and output terminal of the amplifier circuit 130, which is connected to the power supply terminal Vdd of the low noise amplifier 100 on the one hand, and is connected to the RF output terminal 120 on the other hand to output the amplified RF signal.

[0091] As an implementation method, the transconductance value of the second amplifier transistor 132 may also be less than or equal to the transconductance value of the first amplifier transistor 131, so as to reduce the manufacturing cost of the second amplifier transistor 132. Since the first amplifier transistor 131 is a common source transistor and the second amplifier transistor 132 is a common gate transistor, the inventor of the present application has found 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 coefficient of the amplifier circuit, and its influence is far greater than that of the common gate transistor. Therefore, in this implementation method, by increasing the transconductance value of the first amplifier transistor 131 without increasing the transconductance value of the second amplifier transistor 132, the performance of the low noise amplifier can be effectively improved at a relatively low cost.

[0092] As another implementation, the transconductance value of the second amplifying transistor 132 may also be the same as the transconductance value 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 increasing the transconductance values ​​of the common source transistor and the common gate transistor at the same time.

[0093] As an implementation method, 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, and the power supply voltage is used as a bias signal. Then, the bias circuit 140 can be connected to the first amplifying transistor 131 instead of the second amplifying transistor 132, and the bias circuit 140 provides a bias signal for the first amplifying transistor 131.

[0094] Specifically, the bias circuit 140 may include a first bias transistor 141, and the first bias transistor 141 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 source of the first bias transistor 141 and the source of the first amplifying transistor 131 are both grounded. The first bias transistor 141 and the first amplifying transistor 131 may be the same in at least one aspect such as transconductance value, gate doping thickness, gate doping uniformity, and gate doping times, 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 the transconductance value of the first amplifying transistor 131; and / or, the gate doping thickness of the first bias transistor 141 is the same as the gate doping thickness of the first amplifying transistor 131; and / or, the gate doping uniformity of the first bias transistor 141 is the same as the gate doping uniformity of the first amplifying transistor 131; and / or, the gate doping times of the first bias transistor 141 is the same as the gate doping times of the first amplifying transistor 131.

[0095] Exemplarily, the first bias transistor 141 may be manufactured 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 amplifying transistor 131 may be greater than the transconductance value of at least one other transistor in the low noise amplifier, thereby further improving the performance of the low noise amplifier 100 at a lower cost.

[0097] As an implementation method, 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 amplifying circuit 130 respectively, and provide bias current for the first amplifying transistor 131 and the second amplifying transistor 132 in the amplifying circuit 130 together.

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

[0099] Exemplarily, the gate of the first bias transistor 141 is connected to the gate of the first amplifying transistor 131, and the source of the first bias transistor 141 and the source of the first amplifying transistor 131 are both 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 form a cascode current mirror.

[0100] Among them, the first bias transistor 141 and the first amplifier transistor 131 can be the same in at least one aspect such as transconductance value, gate doping thickness, gate doping uniformity, gate doping times, etc., and the second bias transistor 142 and the second amplifier transistor 132 can be the same in at least one aspect such as transconductance value, gate doping thickness, gate doping uniformity, gate doping times, etc., thereby improving the matching degree between the first amplifier transistor 131 and the first bias transistor 141 and the matching degree between the second amplifier 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 the transconductance value of the first amplifying transistor 131; and / or, the gate doping thickness of the first bias transistor 141 is the same as the gate doping thickness of the first amplifying transistor 131; and / or, the gate doping uniformity of the first bias transistor 141 is the same as the gate doping uniformity of the first amplifying transistor 131; and / or, the gate doping times of the first bias transistor 141 is the same as the gate doping times of the first amplifying transistor 131.

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

[0103] Exemplarily, the transconductance value of the first bias transistor 141 is the same as the transconductance value of the first amplifying transistor 131, and the transconductance value of the second bias transistor 142 is the same as the transconductance value of the second amplifying transistor 132. For example, the first bias transistor 141 can be manufactured using the same process as the first amplifying transistor 131, thereby having the same transconductance value; the second bias transistor 142 can be manufactured using the same process as the second amplifying transistor 133, thereby having the same transconductance value, which can maximize the matching degree of the cascode current mirror and improve 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 amplifier transistor 131 may be greater than the transconductance values ​​of the second bias transistor 142 and the second amplifier transistor 132; or, the first bias transistor 141, the first amplifier transistor 131, the second bias transistor 142 and the second amplifier transistor 132 may have the same transconductance value, and the transconductance value is greater than the transconductance value of at least one other transistor (such as a bypass transistor or a switch transistor) in the low noise amplifier. In this way, the performance of the low noise amplifier 100 can be further improved at a lower cost.

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

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

[0107] In this embodiment, since the third bias transistor 143 and the first amplifying transistor 131 or the second amplifying transistor 132 do not form a current mirror, the transconductance value of the third bias transistor 143 can be reduced / not increased, so that the transconductance value of the third bias transistor is smaller 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] As an implementation mode, 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 end of the bias circuit 140, and the other end is grounded. When the amplification circuit 130 is not working, for example, when the low-noise amplifier 100 is in bypass mode, the pull-down switch 144 can be controlled to be turned on to pull the bias signal output by the bias circuit 140 down to the ground.

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

[0110] It should be noted that no matter whether the amplifier circuit 130 adopts a voltage bias method or a current bias method, a pull-down switch 144 can be provided, that is, the pull-down switch 144 can be applied to all bias circuits mentioned in this application.

[0111] In at least one embodiment, Figure 6 As shown, the low noise amplifier 100 may further include a bypass circuit 150, the bypass circuit 150 is connected between the RF input terminal 110 and the RF output terminal 120, and when the low noise amplifier 100 operates in the bypass mode, the RF signal input from the RF input terminal 110 will be output through the bypass circuit 150 instead of the amplifying 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 amplifying transistor 131.

[0112] In the embodiment of the present application, the working mode of the low noise amplifier 100 may include an amplification mode and a bypass mode. When the power of the RF signal input from the RF input terminal 110 is small, the low noise amplifier 100 may work in the amplification mode, amplifying the received weak RF signal and outputting it. When the power of the RF signal input from the RF input terminal 110 is large, the low noise amplifier 100 may work in the bypass mode, so as to directly output the received RF signal or output it after attenuation.

[0113] As an implementation mode, the bypass circuit 150 may include a bypass transistor 151 or a plurality of bypass transistors 151 connected in series, each bypass transistor 151 being 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] It can be understood that in the bypass mode, since the input RF signal power is relatively large, the low noise amplifier 100 has a lower gain requirement and a relatively high tolerance for the noise coefficient. Therefore, the bypass transistor 151 is configured as a transistor that has not undergone transconductance enhancement, that is, the transconductance value of the bypass transistor 151 is smaller than the transconductance value of the first amplifying transistor 131. This can reduce the cost of the low noise amplifier 100 without affecting the performance of the low noise amplifier.

[0115] As an implementation mode, the bypass circuit 150 may further include one or more power attenuation elements for attenuating the power of the RF 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 be connected at one end to the series branch formed by the resistor and the bypass transistor 151, and the other end may be grounded to form a parallel branch.

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

[0117] As an implementation method, Figure 7a As shown, the low noise amplifier 100 includes a bypass circuit 150, and at least one first switch transistor 161 is connected in series between the output end of the bypass circuit 150 and the RF output end 120. When the low noise amplifier 100 operates in the bypass mode, the first switch transistor 161 is turned off to improve the isolation between the amplifying circuit 130 and the bypass circuit 150, and to prevent the RF signal from leaking from the bypass circuit 150 to the amplifying circuit 130. When the low noise amplifier 100 operates in the amplifying mode, the first switch transistor 161 is turned on, so that the RF signal amplified by the amplifying circuit 130 can be transmitted to the RF output end 120 through the turned-on first switch transistor 161. Among them, the transconductance value of the first switch transistor 161 can be less than or equal to the transconductance value of the first amplifying transistor 131.

[0118] As an implementation method, Figure 7bAs shown, the low noise amplifier 100 includes a bypass circuit 150, and at least one second switch transistor 162 is connected in series between the input end of the bypass circuit 150 and the RF input end 110. When the low noise amplifier 100 operates in the bypass mode, the second switch transistor 162 is turned off to improve the isolation between the amplifying circuit 130 and the bypass circuit 150, and to prevent the RF signal from leaking from the bypass circuit 150 to the amplifying circuit 130. When the low noise amplifier 100 operates in the amplifying mode, the second switch transistor 162 is turned on, so that the RF signal input from the RF input end 110 can be transmitted to the amplifying circuit 130 through the turned-on second switch transistor 162, so as to be amplified by the amplifying circuit 130. Among them, the transconductance value of the second switch transistor 162 can be less than or equal to the transconductance value of the first amplifying transistor 131.

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

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

[0121] It can be understood that, in the bypass mode, the RF signal is mainly transmitted through the bypass circuit 150 instead of the amplifying circuit 130 and the first switch transistor 161 and / or the second switch transistor 162 connected in series with the amplifying circuit 130, and the magnitude of the transconductance value of the first switch transistor 161 and / or the second switch transistor 162 has almost no effect on the performance of the low noise amplifier 100 in the bypass mode. Even in the amplifying mode, the RF signal will pass through the turned-on first switch transistor 161 and / or the second switch transistor 162, but since the first switch transistor 161 and / or the second switch transistor 162 do not amplify the signal, the magnitude of the transconductance value of the first switch transistor 161 and / or the second switch transistor 162 has very little effect on the performance of the low noise amplifier 100 in the amplifying mode.

[0122] Therefore, the first switch transistor 161 and the second switch transistor 162 are configured as transistors that have not undergone transconductance enhancement, and the transconductance values ​​of the first switch transistor 161 and the second switch transistor 162 are smaller than the transconductance value of the first amplifier 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 all of the first switching transistor 161 and the second switching transistor 162 can also be configured as a transistor having the same transconductance value as the first amplifying transistor 131, and at least one other transistor in the low-noise amplifier 100 (such as a bias transistor, a bypass transistor, and at least one of the other switching transistors) can be configured as a transistor with a smaller transconductance value to achieve cost control.

[0124] As an implementation method, Figure 8 As shown, the low noise amplifier 100 includes M RF input terminals 110 and M first switch branches 163 corresponding to the M RF input terminals one by one, each RF input terminal is connected to the amplification circuit through the corresponding first switch branch 163, and each first switch branch 163 includes at least one switching transistor, wherein M is a positive integer and M≥2.

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

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

[0127] It is understandable that, although in the amplification mode, the RF signal will pass through the switch transistor in the turned-on first switch branch 163 before being input into the amplifier circuit 130, the switch transistor does not amplify the signal, so the transconductance value of the switch transistor in the first switch branch 163 has very little effect on the performance of the low noise amplifier. Based on this, this embodiment configures at least one switch transistor as a transistor that has not undergone transconductance enhancement, so that its transconductance value is smaller than the transconductance value of the first amplification transistor 131, and can reduce the cost of the low noise amplifier 100 without affecting the performance of the low noise amplifier.

[0128] Optionally, the transconductance values ​​of some switching transistors in each first switching branch 163 can be configured to be smaller 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; the transconductance values ​​of all switching transistors in each first switching branch 163 can also be configured to be smaller 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, Fig. 9 As shown, the amplifier circuit 130 may include multiple amplifier branches, and the multiple amplifier branches are connected to multiple RF input terminals 110 in a one-to-one correspondence. For example, the amplifier circuit 130 may include M amplifier branches, each amplifier branch corresponds to a switch branch 163 and a RF input terminal 110, and the M amplifier branches are connected to the corresponding M RF input terminals 110 (specifically 111 to 11M) through corresponding switch branches 163 (specifically 1631 to 163M).

[0130] Optionally, each amplifying branch includes one or more amplifying transistors. When each amplifying branch includes multiple amplifying transistors, multiple amplifying branches may reuse some transistors to reduce the number of transistors required for the amplifying circuit 130, which is beneficial to the miniaturization design of the low noise amplifier. Fig. 9 As shown, each of the M amplifying branches may be provided with a non-reused common-source amplifier (i.e., the first amplifying transistor 131), and the M amplifying branches reuse a common-gate amplifier (i.e., the second amplifying transistor 132). In the common-source and common-gate amplifying structure, the common-source amplifier has the greatest impact on the performance of the entire amplifying circuit. By setting multiple amplifying branches to reuse common-gate amplifiers instead of common-source amplifiers, 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 reducing costs.

[0131] As an implementation, when the amplifier circuit 130 includes multiple first amplifier transistors 131, the first amplifier transistors 131 in all amplifier branches can be configured to adopt the same manufacturing process and have the same high transconductance value to maximize the performance of the low noise amplifier 100.

[0132] As another implementation, when the amplifier circuit 130 includes multiple first amplifier transistors 131, the first amplifier transistors 131 in some amplifier branches can be configured to have higher transconductance values, while the first amplifier transistors 131 in other amplifier branches can have smaller transconductance values, according to the frequency bands and bandwidths of the RF signals corresponding to different amplifier branches, or according to different performance requirements for different amplifier branches, thereby improving the performance of some amplifier branches in the low-noise amplifier 100 at a lower cost.

[0133] As an implementation method, Figure 8 and Fig. 9 As shown, the low noise amplifier 100 includes N RF output terminals 120 and N second switch branches 164 corresponding to the N RF output terminals 120 one by one, each RF output terminal 120 is connected to the output terminal of the amplifier circuit through the corresponding second switch branch 164, and each second switch branch 164 includes at least one switching transistor, wherein N is a positive integer and N≥2.

[0134] In this embodiment, by controlling the switch states (such as on or off) of the N second switch branches 164, the RF signals of different frequency bands output by the amplifying 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, there may not be a one-to-one correspondence between the RF output terminals 120 and the frequency bands of the RF signals, and one RF output terminal 120 may be used to output RF signals of one frequency band, or may be used to output RF signals of multiple frequency bands.

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

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

[0137] Optionally, the transconductance values ​​of some switching transistors in each second switching branch 164 can be configured to be smaller 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; the transconductance values ​​of all switching transistors in each second switching branch 164 can also be configured to be smaller 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 includes 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, 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, Figure 2a or Figure 3a As shown, the second inductor L2 is connected in series between the power supply end and the output end of the amplifier circuit; the second inductor L2 can act as a choke to isolate the signal interference between the DC power supply signal and the RF signal, thereby improving the stability and reliability of the low noise amplifier 100.

[0141] For example, Fig.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 previous stage circuit to reduce the loss of the RF signal during the transmission from the previous stage circuit to the RF input terminal. Optionally, the input matching circuit may include at least one third inductor L3, and the third inductor L3 is connected in series between the previous stage circuit and the RF input terminal. For example, Fig.10As shown, when the low noise amplifier 110 has multiple RF input terminals 110, one or more third inductors L3 are respectively connected in series between each RF input terminal 110 and the corresponding pre-stage circuit, wherein the inductance value of the third inductor L3 connected to each RF input terminal 110 may be different depending on the frequency band of the input RF signal.

[0142] The front-stage circuit may be any circuit element between the antenna and the low noise amplifier, for example, a filter or a switch chip in the RF front-end module. When the low noise amplifier 110 has multiple RF input terminals 110, different RF input terminals 110 may be connected to the output terminals of different filters, or to different ports of the switch chip.

[0143] Optionally, the third inductor L3 in the input matching circuit may be integrated into the chip together with each transistor, or may be disposed on the substrate and implemented through metal wiring of the substrate wiring layer or using SMD devices, which is not limited in the present application.

[0144] For example, Fig.10 As shown, the output matching circuit 180 is connected between the output end of the amplifier circuit and the RF output end; 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 the transmission from the RF output end 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 thereof is not limited in this application.

[0145] For example, Fig.10 As shown, the low noise amplifier 100 includes a power discharge branch 190, one end of the power discharge branch 190 is connected to the RF input terminal 110, the other end of the power discharge branch is grounded, and the power discharge branch 190 includes a resistor R1 and a switch S1 connected in series. When the input power of the RF signal is too large, the low noise amplifier 100 can control the switch S1 in the power discharge branch 190 to be turned on, so that part of the input power is discharged to the ground through the turned-on switch S1 and the resistor R1, thereby reducing the input power of the amplifier circuit 130, avoiding the amplifier circuit 130 from 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 may be one or more. When the low noise amplifier 100 includes multiple RF input terminals 110, the number of power discharge branches 190 may be less than or equal to the number of RF input terminals 110, and the power discharge branches 190 may be set only between some of the RF input terminals 110 and the ground terminal, or between each RF input terminal 110 and the ground terminal. The present application does not limit this.

[0147] As an implementation, the switch S1 in the power discharge branch 190 includes one or more switch transistors, and the transconductance value of the switch transistor may be less than or equal to the transconductance value of the first amplifying transistor. Exemplarily, the transconductance value of the switch transistor is less than the transconductance value of the first amplifying transistor, which can further reduce the cost of the low noise amplifier 100 without affecting the performance of the low noise amplifier.

[0148] In at least one embodiment, the low noise amplifier is integrated in a chip having a silicon-on-insulator substrate. Using silicon-on-insulator material as a substrate not only helps to improve the transconductance value of the first amplifying transistor, but also can reduce the parasitic capacitance of each transistor and reduce the power consumption of the transistor, so that the performance of the low noise amplifier 100 is significantly improved.

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

[0150] As an implementation manner, a transconductance value of the first amplifying transistor is greater than or equal to 1.8 millisiemens / mm.

[0151] As an implementation manner, the low noise amplifier further includes a bypass circuit 150, wherein the bypass circuit includes at least one bypass transistor having a transconductance value less than or equal to 1.65 milliSiemens / mm.

[0152] As an implementation manner, the low noise amplifier further includes a bias circuit 140, wherein the bias circuit includes at least one bias transistor having a transconductance value less than or equal to 1.65 milliSiemens / mm.

[0153] As an implementation manner, the low noise amplifier further includes a switching circuit, wherein the switching circuit includes at least one switching transistor having a transconductance value 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 of this embodiment, the magnitude relationship of the transconductance values ​​between different transistors, etc., refer to the relevant introduction of the low noise amplifier 100 provided in the first aspect, and will not be repeated here.

[0155] The embodiment of the present application can increase the gain of the low noise amplifier 100 and reduce the noise factor of the low noise amplifier 100 by increasing the transconductance value of the first amplifying transistor in the low noise amplifier 100 to above 1.7 millisiemens / mm, thereby improving the overall performance of the low noise amplifier 100.

[0156] The third aspect of the present application further provides a radio frequency front-end module 200, comprising the low noise amplifier 100 shown in any of the above embodiments.

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

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

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

[0160] A fourth aspect of the present application further provides an electronic device, comprising the low noise amplifier 100 or the RF front-end module 200 shown in any of the above embodiments.

[0161] Among them, the electronic device can be a communication device such as a mobile phone, a tablet computer, a vehicle-mounted terminal, and of course, it can also be other communication devices with communication functions. The embodiments of the present application do not limit the specific type of the electronic device.

[0162] The above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments can still be modified, or some of the technical features can be replaced by equivalents. However, these modifications or replacements 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 the present application.

Claims

1. A low noise amplifier, characterized in that: The low noise amplifier comprises a radio frequency input terminal, a radio frequency output terminal and an amplifier circuit connected between the radio frequency input terminal and the radio frequency output terminal, wherein the amplifier circuit comprises at least a first amplifier transistor; 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.

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

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

4. The low noise amplifier according to claim 1, characterized in that: The transconductance value of the first amplifying transistor is greater than or equal to 1.7 millisiemens / mm; the low noise amplifier also includes at least one other transistor with a transconductance value 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 in a chip having an SOI substrate, and a transconductance value 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 value 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 amplifying circuit further includes a second amplifying transistor, and a transconductance value of the second amplifying transistor is less than or equal to a transconductance value of the first amplifying transistor.

8. The low noise amplifier according to claim 1, characterized in that: The amplifier circuit further includes a bias circuit and a first capacitor. The bias circuit is connected to the first end of the first amplifier transistor. The first end of the first amplifier transistor is connected to the RF input end through the first capacitor.

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

10. The low noise amplifier according to claim 8, characterized in that: The bias circuit includes a first bias transistor, wherein the first bias transistor is connected to the first amplifying transistor to form a current mirror; Among them, 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 gate doping times of the first bias transistor is the same as the gate doping times of the first amplifying transistor.

11. The low noise amplifier according to claim 8, characterized in that: The bias circuit includes a second bias transistor, the second bias transistor does not form a current mirror with the first amplifying transistor, and a transconductance value of the second bias transistor is less than or equal to a transconductance value of the first amplifying transistor.

12. The low noise amplifier according to claim 10, characterized in that: The bias circuit comprises at least two voltage-dividing elements, the at least two voltage-dividing elements are connected in series, and the first amplifying transistor is connected to a connection node of two adjacent voltage-dividing elements; At least part of the voltage divider elements are third bias transistors, and the transconductance value of the third bias transistor is smaller than the transconductance value of the first amplifying transistor.

13. The low noise amplifier according to any one of claims 8 to 12, characterized in that: The second end of the first amplifying transistor is a power supply end and an output end of the amplifying circuit, and the third end of the first amplifying transistor is used for grounding.

14. The low noise amplifier according to any one of claims 8 to 12, characterized in that: The amplifying circuit further comprises a second amplifying transistor, the second end of the first amplifying transistor is connected to the third end of the second amplifying transistor, and the third end of the first amplifying transistor is used for grounding; The first end of the second amplifying transistor is connected to the power supply end of the bias circuit or the low noise amplifier, and the second end of the second amplifying transistor is the power supply end and the output end of the amplifying circuit.

15. The low noise amplifier according to claim 14, characterized in that: The bias circuit further includes a second bias transistor, a first terminal of the second bias transistor is connected to the first terminal of the second amplifying transistor, and a transconductance of the second bias transistor is the same as a transconductance of the second amplifying transistor.

16. The low noise amplifier according to claim 14, characterized in that: The bias circuit comprises at least three voltage-dividing elements, which are connected in series and have at least two connection nodes; the first end of the first amplifying transistor and the first end of the second amplifying transistor are respectively connected to different connection nodes; The at least three voltage-dividing elements include at least two third biasing transistors and at least one voltage-dividing resistor; or the at least three voltage-dividing elements are at least three third biasing transistors.

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

18. The low noise amplifier according to claim 1, characterized in that: The low noise amplifier further comprises one or more switch transistors, wherein a transconductance value of at least one of the switch transistors is smaller than a transconductance value of the first amplifying transistor.

19. The low noise amplifier according to claim 18, characterized in that: The low noise amplifier includes M RF input terminals and M switch branches corresponding to the M RF input terminals one by one, each of the RF input terminals is connected to the amplifier circuit through a corresponding switch branch, wherein each of the switch branches includes at least one switch transistor, M is a positive integer and M≥2.

20. The low noise amplifier according to any one of claims 1 to 12 and 17 to 19, characterized in that: The transistors in the low noise amplifier are field effect transistors, and the first end of each transistor is a gate, the second end is a drain, and the third end is a source.

21. The low noise amplifier according to claim 20, characterized in that: The low noise amplifier is integrated in a chip having a silicon-on-insulator substrate.

22. A low noise amplifier, characterized in that: The low noise amplifier includes a radio frequency input terminal, a radio frequency output terminal and an amplifier circuit connected between the radio frequency input terminal and the radio frequency output terminal, and the amplifier circuit includes at least a first transistor; wherein the transconductance value of the first amplifier transistor is greater than or equal to 1.7 millisiemens / mm.

23. The low noise amplifier according to claim 22, characterized in that: The transconductance value of the first amplifying transistor is greater than or equal to 1.8 millisiemens / mm.

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

25. The low noise amplifier according to claim 22, characterized in that: The low noise amplifier further comprises a bypass circuit, wherein the bypass circuit comprises at least one bypass transistor having a transconductance value less than or equal to 1.65 milliSiemens / mm; and / or The low noise amplifier further comprises a bias circuit, wherein the bias circuit comprises at least one bias transistor having a transconductance value less than or equal to 1.65 millisiemens / mm; and / or The low noise amplifier further includes a switch circuit, wherein the switch circuit includes at least one switch transistor having a transconductance value less than or equal to 1.65 milliSiemens / mm.

26. A radio frequency front-end module, characterized in that: Comprising a low noise amplifier as described in any one of claims 1-25.

27. An electronic device, characterized in that: It comprises a low noise amplifier as described in any one of claims 1 to 25 or a radio frequency front-end module as described in claim 26.

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