Low noise amplifier circuit and radio frequency front end module

Abstract

The application provides a low-noise amplification circuit and a radio frequency front-end module, wherein the low-noise amplification circuit comprises an input matching adjustment circuit, a common-source amplification circuit, a source-end degeneration circuit, an impedance adjustment circuit, a common-gate amplification circuit, an inter-stage matching circuit, an input-output feedback circuit, an output matching adjustment circuit and an output attenuation circuit; the common-source amplification circuit comprises a first field effect transistor; the source-end degeneration circuit comprises at least one source-end degeneration inductor; the impedance adjustment circuit comprises at least one first capacitor; the impedance adjustment circuit and the source-end degeneration circuit are used for adjusting the input impedance of the low-noise amplification circuit. The application can make the low-noise amplification circuit better match the module or external circuit, realize gear switching of different gains, and improve the integration of the low-noise amplification circuit, so that the overall area is not wasted too much.

Description

Technical Field

[0001] This invention relates to the field of communication technology, and in particular to a low-noise amplifier circuit and a radio frequency front-end module. Background Technology

[0002] As the first-stage active amplifier in the RF front-end link, the low-noise amplifier needs to receive and amplify weak RF signals from the antenna or external environment, and transmit the amplified signal to the next stage circuit module as lossless as possible. Therefore, the low-noise amplifier needs to have strong noise suppression and distortion resistance to ensure the receiving sensitivity of the RF link.

[0003] like Figure 1 As shown, the radio frequency signal (RFIN') from the antenna or external environment first passes through the input matching adjustment circuit for impedance matching, and then provides a suitable voltage or current signal to the core radio frequency amplifier circuit through the bias source, so that the core radio frequency amplifier circuit operates in the correct amplification mode to amplify the received radio frequency signal and suppress the signal of the next stage. After the core radio frequency amplifier circuit finishes processing the amplified signal, it will transmit it to the output matching adjustment circuit, which will match the impedance at the output end to output the amplified radio frequency signal (RFOUT') to the next stage circuit module.

[0004] The aforementioned core RF amplifier circuit typically uses a metal-oxide-semiconductor field-effect transistor (MOSFET) to implement a two-stage cascaded common-source gate (CSCG) amplifier circuit. Its input matching adjustment circuit is usually implemented by a combination of external or internal input impedance inductors, on-chip capacitors, and on-chip inductors.

[0005] like Figure 2 As shown, the low-noise amplifier in the related technology mainly includes an input matching adjustment circuit, a common-source amplifier circuit, a source degradation circuit, a common-gate amplifier circuit, an interstage matching circuit, an input-output feedback circuit, an output matching adjustment circuit, an output attenuation circuit, a capacitor C1', and a capacitor C2'. Among them, the common-source amplifier circuit includes a first field-effect transistor (M1') and a first resistor (R1') for connecting a first bias voltage (VB1'). The source degradation circuit includes a single-port or multi-port inductor (LS'), or multiple switches combined with multiple inductors (LS') to realize the function of switching different inductors (LS') and resistors. The common-gate amplifier circuit includes a second field-effect transistor (M2') and a second resistor (R2') for connecting a second bias voltage (VB2').

[0006] In the design of low-noise amplifiers using related technologies, the input impedance relationship of their common-source cascode structure is as follows:

[0007] ; The conditions of the department are as follows: ; in, Zin For input impedance, j The virtual part, ω Angular frequency, Lg The gate inductance of the first field-effect transistor (M1') Cgs1 This is the gate-source capacitance of the first field-effect transistor (M1'). Ls This represents the degraded inductance value at the source end; gm1 For the transconductance of the first field-effect transistor (M1'), Rin This represents the real part of the input impedance.

[0008] The aforementioned low-noise amplifiers typically have a suitable transconductance (gm) value for the first field-effect transistor (M1'). At the same time, the inductance value of the source-side degenerate inductor (LS') of the first field-effect transistor (M1') is increased, or the parasitic resistance value of the inductor (LS') is increased to increase the impedance, so as to better match the module or external circuit, or to achieve other low-to-medium gain functions. In this case, the area of ​​the inductor (LS') needs to be very large, and an additional large switch is needed to switch the inductor in different modes. Both of these methods result in a significant waste of the low-noise amplifier's area.

[0009] Therefore, a low-noise amplifier circuit and RF front-end module are needed to solve the above problems. Summary of the Invention

[0010] To address the shortcomings of the aforementioned related technologies, this invention proposes a novel low-noise amplifier circuit and RF front-end module to solve the problem of significant waste of overall area in low-noise amplifiers in related technologies due to the need for better matching or switching between different gain levels.

[0011] To solve the above-mentioned technical problems, in a first aspect, the present invention provides a low-noise amplifier circuit, which includes an input matching adjustment circuit, a common-source amplifier circuit, a source-end degradation circuit, an impedance adjustment circuit, a common-gate amplifier circuit, an interstage matching circuit, an input-output feedback circuit, an output matching adjustment circuit, and an output attenuation circuit. The input terminal of the input matching adjustment circuit is used to receive radio frequency signals; The common-source amplifier circuit includes a first field-effect transistor (FET), the gate of which serves as the input terminal of the common-source amplifier circuit and is used to connect to a first bias voltage and the output terminal of the input matching adjustment circuit, respectively. The drain of the first FET serves as the output terminal of the common-source amplifier circuit. The source degradation circuit includes at least one source degradation inductor, the first terminals of all the source degradation inductors are respectively connected to the source of the first field-effect transistor, and the second terminals of all the source degradation inductors are respectively grounded; The impedance adjustment circuit includes at least one first capacitor; the first terminals of all the first capacitors are connected together and then connected to the output terminal of the common source amplifier circuit, and the second terminals of all the first capacitors are connected together and then grounded; the impedance adjustment circuit and the source degradation circuit are used together to adjust the input impedance of the low noise amplifier circuit. The first input terminal of the common-gate amplifier circuit is used to connect to the second bias voltage, and the second input terminal of the common-gate amplifier circuit is connected to the output terminal of the common-source amplifier circuit. The input terminal of the interstage matching circuit is connected to the output terminal of the common-source amplifier circuit, and the output terminal of the interstage matching circuit is grounded. The input terminal of the input-output feedback circuit is connected to the input terminal of the common-source amplifier circuit, and the output terminal of the input-output feedback circuit is connected to the output terminal of the common-gate amplifier circuit. The input terminal of the output matching adjustment circuit is used to connect to the operating voltage, and the output terminal of the output matching adjustment circuit is connected to the output terminal of the common-gate amplifier circuit. The input terminal of the output attenuation circuit is connected to the output terminal of the common-gate amplifier circuit, and the output terminal of the output attenuation circuit is used to output radio frequency signals.

[0012] Preferably, the impedance adjustment circuit includes a plurality of first capacitors; the impedance adjustment circuit further includes a plurality of single-pole single-throw switches; the number of first capacitors is defined as n, and the number of single-pole single-throw switches is n-1, where n is a positive integer greater than or equal to 2; One of the first capacitors is connected to the control terminal of all the single-pole single-throw switches and is connected to the output terminal of the common-source amplifier circuit. The first terminal of each of the remaining first capacitors is connected to the output terminal of one of the single-pole single-throw switches. The second terminals of all the first capacitors are connected to each other and are grounded together.

[0013] Preferably, the common-source amplifier circuit further includes a first resistor; the first end of the first resistor is connected to the gate of the first field-effect transistor, and the second end of the first resistor is used to connect to a first bias voltage.

[0014] Preferably, the common-gate amplifier circuit includes a second resistor and a second field-effect transistor; The first terminal of the second resistor serves as the first input terminal of the common-gate amplifier circuit. The gate of the second field-effect transistor is connected to the second terminal of the second resistor, the source of the second field-effect transistor serves as the second input terminal of the common-gate amplifier circuit, and the drain of the second field-effect transistor serves as the output terminal of the common-gate amplifier circuit.

[0015] Preferably, the low-noise amplifier circuit further includes a second capacitor; the first terminal of the second capacitor is connected to the input terminal of the output matching adjustment circuit, and the second terminal of the second capacitor is grounded.

[0016] Preferably, the low-noise amplifier circuit further includes a third capacitor; the first terminal of the third capacitor is connected to the output terminal of the common-gate amplifier circuit and the output terminal of the output matching adjustment circuit, respectively, and the second terminal of the third capacitor is connected to the input terminal of the output attenuation circuit.

[0017] Secondly, the present invention provides a radio frequency front-end module, which includes the low-noise amplifier circuit described above.

[0018] Compared with related technologies, the low-noise amplifier circuit of the present invention adds an impedance adjustment circuit at the output terminal of the common-source amplifier circuit, which, together with the source-end degradation circuit, is used to adjust the input impedance of the low-noise amplifier circuit. The impedance adjustment circuit includes at least one first capacitor. The first terminals of all the first capacitors are connected together and connected to the output terminal of the common-source amplifier circuit. The second terminals of all the first capacitors are connected together and grounded. In this way, the inductance value of the source-end degradation inductor in the source-end degradation circuit can be designed to be very small, and there is no need to continuously change its inductance value. Only the capacitance value of the first capacitor in the impedance adjustment circuit needs to be changed to realize the transformation of the input impedance of the low-noise amplifier circuit. This allows the low-noise amplifier circuit to better match with modules or external circuits, or to realize the switching of different gain levels, and improve the integration of the low-noise amplifier circuit, so that its overall area is not wasted too much. Attached Figure Description

[0019] The present invention will now be described in detail with reference to the accompanying drawings. The above and other aspects of the present invention will become clearer and more readily understood through the detailed description following the accompanying drawings. In the drawings: Figure 1 A schematic diagram of a low-noise amplifier provided for related technologies; Figure 2 Circuit diagram of a low-noise amplifier provided for related technologies; Figure 3 A circuit diagram of a low-noise amplifier circuit provided in an embodiment of the present invention; Figure 4 A Smith chart comparing the input impedance of the low-noise amplifier circuit provided in the embodiments of the present invention with the input impedance of low-noise amplifiers in related technologies; Figure 5 A comparison diagram of the input return loss of the low-noise amplifier circuit provided in the embodiments of the present invention and the input return loss of low-noise amplifiers in related technologies. Figure 6 A comparison diagram of the reverse isolation of the low-noise amplifier circuit provided in the embodiments of the present invention and the reverse isolation of low-noise amplifiers in related technologies; Figure 7 A comparison diagram of the gain of the low-noise amplifier circuit provided in the embodiments of the present invention and the gain of low-noise amplifiers in related technologies; Figure 8 A comparison diagram of the noise figure of the low-noise amplifier circuit provided in the embodiments of the present invention and the noise figure of the low-noise amplifier in the related art. Detailed Implementation

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein in the specification of the application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "comprising" and "having," and any variations thereof, in the specification, claims, and foregoing drawings of this application, are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the specification, claims, or foregoing drawings of this application are used to distinguish different objects, not to describe a particular order.

[0021] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0023] Example 1 This invention provides a low-noise amplifier circuit 100, such as... Figure 3As shown, it includes an input matching adjustment circuit 1, a common-source amplifier circuit 2, a source-end degradation circuit 3, an impedance adjustment circuit 4, a common-gate amplifier circuit 5, an interstage matching circuit 6, an input-output feedback circuit 7, an output matching adjustment circuit 8, and an output attenuation circuit 9.

[0024] The input terminal of the input matching adjustment circuit 1 is used to receive the radio frequency signal RFIN.

[0025] The input matching adjustment circuit 1 includes an input matching inductor, a DC blocking capacitor, and multiple capacitors to ground, etc., to achieve input impedance matching and tuning functions in different frequency bands.

[0026] The common-source amplifier circuit 2 includes a first field-effect transistor M1. The gate of the first field-effect transistor M1 serves as the input terminal of the common-source amplifier circuit 2, and is used to connect to the first bias voltage VB1 and the output terminal of the input matching adjustment circuit 1, respectively. The drain of the first field-effect transistor M1 serves as the output terminal of the common-source amplifier circuit 2.

[0027] In this embodiment, the common-source amplifier circuit 2 further includes a first resistor R1; the first end of the first resistor R1 is connected to the gate of the first field-effect transistor M1, and the second end of the first resistor R1 is used to connect to the first bias voltage VB1.

[0028] Depending on actual needs, a switch can be added to the common source amplifier circuit 2 to enable or disable the common source amplifier circuit 2; the first bias voltage VB1 can also be replaced with a current source.

[0029] The source degradation circuit 3 includes at least one source degradation inductor LS. The first terminals of all source degradation inductors LS are respectively connected to the source of the first field-effect transistor M1, and the second terminals of all source degradation inductors LS are respectively grounded. In this embodiment, the source degradation circuit 3 includes one source degradation inductor LS.

[0030] The source-side degradation inductor LS can be a single-port inductor or a multi-port inductor. Of course, in special cases, such as when the number of first capacitors is too small or when the source-side degradation inductors LS have already been installed, the source-side degradation circuit 3 can also use a design with multiple source-side degradation inductors LS and multiple switches to achieve the function of switching between different inductors and resistors.

[0031] Impedance adjustment circuit 4 includes at least one first capacitor; the first terminals of all the first capacitors are connected together and then connected to the output terminal of common source amplifier circuit 2, and the second terminals of all the first capacitors are connected together and then grounded; impedance adjustment circuit 4 and source degradation circuit 3 are used together to adjust the input impedance of low noise amplifier circuit 100.

[0032] The impedance adjustment circuit 4 allows for a very small inductance value of the source degradation inductor LS in the source degradation circuit 3. Furthermore, it eliminates the need for continuous changes in inductance; simply altering the capacitance of the first capacitor in the impedance adjustment circuit 4 is sufficient to change the input impedance of the low-noise amplifier circuit 100. This enables better matching of the low-noise amplifier circuit 100 with modules or external circuits, facilitates switching between different gain levels, and improves the integration of the low-noise amplifier circuit 100 without excessive waste of space. The impedance adjustment circuit 4 can also increase the real impedance of the low-noise amplifier circuit 100 when the source degradation circuit 3 is already installed.

[0033] The design principle of impedance adjustment circuit 4 is as follows: By adding a first capacitor, the input impedance of low-noise amplifier circuit 100 can be transformed into a series RC circuit (Resistor-Capacitance Circuit). When the capacitance value of the first capacitor is large enough, the impedance point of interstage matching circuit 6 will change from 1 / gm2 to 1 (jwCd). The effect of Cgd on reducing the input impedance of low-noise amplifier circuit 100 will be weakened, and the input impedance of low-noise amplifier circuit 100 will increase. Therefore, at high frequencies, the first capacitor will form an LC resonance with the trace inductance or bond wire inductance to improve the impedance of interstage matching circuit 6 at a specific frequency. Here, gm2 is the transconductance of the second field-effect transistor M2, j is the imaginary part, w is the angular frequency, Cd is the capacitance value of all conducting first capacitors, and Cgd is the capacitance value between the gate and drain of the first field-effect transistor M1.

[0034] In addition, the Q value (quality factor) of on-chip capacitors is greater than 200, while the Q value of on-chip inductors is generally 30. Therefore, the Q value of the first capacitor is much higher than the Q value of the source-side degraded inductor LS, which can improve the RF performance of the low-noise amplifier circuit 100.

[0035] To further achieve matching of the low-noise amplifier circuit 100 or switching between different gain levels, the impedance adjustment circuit 4 can also be designed to include multiple first capacitors; the impedance adjustment circuit 4 also includes multiple single-pole single-throw switches; the number of first capacitors is defined as n, and the number of single-pole single-throw switches is n-1, where n is a positive integer greater than or equal to 2.

[0036] One of the first capacitors is connected to the control terminal of all single-pole single-throw switches and is connected to the output terminal of the common-source amplifier circuit 2. The first terminal of each of the remaining first capacitors is connected to the output terminal of a single-pole single-throw switch. The second terminals of all the first capacitors are connected to each other and grounded together.

[0037] In this embodiment, the impedance adjustment circuit 4 includes three first capacitors, namely... Figure 3 C11, C12, and C13 are listed in the code. Correspondingly, there are two single-pole single-throw switches, namely C11, C12, and C13. Figure 3 S11 and S12 in the circuit. Of course, depending on the actual needs, the impedance adjustment circuit 4 can also be designed to include two first capacitors, four first capacitors, five first capacitors, etc., and the number of single-pole single-throw switches will change accordingly.

[0038] The first input terminal of the common-gate amplifier circuit 5 is used to connect the second bias voltage VB2, and the second input terminal of the common-gate amplifier circuit 5 is connected to the output terminal of the common-source amplifier circuit 2.

[0039] In this embodiment, the common-gate amplifier circuit 5 includes a second resistor R2 and a second field-effect transistor M2.

[0040] The first terminal of the second resistor R2 serves as the first input terminal of the common-gate amplifier circuit 5.

[0041] The gate of the second field-effect transistor M2 is connected to the second terminal of the second resistor R2. The source of the second field-effect transistor M2 serves as the second input terminal of the common-gate amplifier circuit 5, and the drain of the second field-effect transistor M2 serves as the output terminal of the common-gate amplifier circuit 5.

[0042] Depending on the actual needs, the second bias voltage VB2 can also be replaced with a current source.

[0043] The input terminal of the interstage matching circuit 6 is connected to the output terminal of the common-source amplifier circuit 2, and the output terminal of the interstage matching circuit 6 is grounded.

[0044] The interstage matching circuit 6 includes resistors, capacitors, and switches, etc., to achieve attenuation.

[0045] The input terminal of the input-output feedback circuit 7 is connected to the input terminal of the common-source amplifier circuit 2, and the output terminal of the input-output feedback circuit 7 is connected to the output terminal of the common-gate amplifier circuit 5.

[0046] The input / output feedback circuit 7 includes resistors, capacitors, and switches, which are used to form a passive amplification via to achieve attenuation of large signals in the passive amplification path.

[0047] The input terminal of the output matching adjustment circuit 8 is used to connect the working voltage VDD, and the output terminal of the output matching adjustment circuit 8 is connected to the output terminal of the common grid amplifier circuit 5.

[0048] The output matching and adjustment circuit 8 includes an output matching inductor, a DC blocking capacitor, and multiple capacitors to ground, which are used to achieve output impedance matching and tuning functions in different frequency bands.

[0049] The input terminal of the output attenuation circuit 9 is connected to the output terminal of the common-gate amplifier circuit 5, and the output terminal of the output attenuation circuit 9 is used to output the radio frequency signal RFOUT.

[0050] The output attenuation circuit 9 includes multiple resistors, capacitors, and switches, which are used to realize the function of the attenuator and achieve the gain requirements of the amplified signal in different working scenarios.

[0051] In this embodiment, the low-noise amplifier circuit 100 further includes a second capacitor C2 and a third capacitor C3.

[0052] The first terminal of the second capacitor C2 is connected to the input terminal of the output matching adjustment circuit 8, and the second terminal of the second capacitor C2 is grounded.

[0053] The first end of the third capacitor C3 is connected to the output of the common-gate amplifier circuit 5 and the output of the output matching adjustment circuit 8, respectively, and the second end of the third capacitor C3 is connected to the input of the output attenuation circuit 9.

[0054] When the low-noise amplifier circuit 100 of this embodiment is designed independently, it can be applied to the highest level to increase the input impedance of the low-noise amplifier circuit 100, thereby obtaining higher gain and NF (Noise Figure).

[0055] When the low-noise amplifier circuit 100 of this embodiment is applied to a radio frequency front-end module (LDiFEM) or a receiver module, the capacitance value of the first capacitor under different radio frequency bands can be adjusted by switching the single-pole single-throw switch in the impedance adjustment circuit 4, thereby matching the filter impedance and obtaining the best impedance and noise matching, while having good isolation.

[0056] When the low-noise amplifier circuit 100 of this embodiment is applied to scenarios such as low-noise amplifier banks (LNA banks) with multiple input ports, different low-to-medium performance levels can be obtained by switching the single-pole single-throw switch in the impedance adjustment circuit 4.

[0057] Figure 4 In the figure, one curve is the input impedance curve of the low noise amplifier circuit 100 in this embodiment, and the other two curves are the input impedance curves of the low noise amplifier with a source-end degradation inductor value of 300pH in the related art, and the input impedance curves of the low noise amplifier with an increased source-end degradation inductor value in the related art.

[0058] Figure 5In the figure, one curve is the input return loss curve of the low noise amplifier circuit 100 in this embodiment. The other two curves are the input return loss curve of the low noise amplifier with a source-end degradation inductor value of 300pH in the related art, and the input return loss curve of the low noise amplifier with an increased source-end degradation inductor value in the related art.

[0059] Figure 6 In the figure, one curve is the reverse isolation curve of the low noise amplifier circuit 100 in this embodiment, and the other two curves are the reverse isolation curves when the inductance value of the source-end degradation inductor of the low noise amplifier in the related art is 300pH, and the reverse isolation curves after the inductance value of the source-end degradation inductor of the low noise amplifier in the related art is increased.

[0060] Figure 7 In the figure, one curve is the gain curve of the low-noise amplifier circuit 100 in this embodiment, and the other two curves are the gain curves of the low-noise amplifier with a source-end degradation inductor value of 300pH in the related art, and the gain curves of the low-noise amplifier with an increased source-end degradation inductor value in the related art.

[0061] Figure 8 In the figure, one curve is the noise figure curve of the low-noise amplifier circuit 100 in this embodiment, and the other two curves are the noise figure curves of the low-noise amplifier with a source-end degradation inductor value of 300pH in the related art, and the noise figure curves of the low-noise amplifier with an increased source-end degradation inductor value in the related art.

[0062] pass Figure 4 It is known that the input impedance of the low-noise amplifier circuit 100 in this embodiment is very low, approximately 25 Ohms. However, methods used in related low-noise amplifiers can increase the real part of their input impedance to around 50 Ohms. At this point, the inductance value is approximately 820 pF, while the capacitance value is only 1.3 pF. Therefore, setting the input impedance of both the low-noise amplifier circuit 100 in this embodiment and the low-noise amplifiers in related technologies to around 50 Ohms is the optimal choice for comparing gain and noise figure. Figures 5 to 8 As can be seen, the performance of the low-noise amplifier circuit 100 in this embodiment is superior to that of the low-noise amplifier in the related technology. For example, the reverse isolation of the low-noise amplifier circuit 100 in this embodiment is about 3dB higher than that of the low-noise amplifier in the related technology. The gain of the low-noise amplifier circuit 100 in this embodiment is about 1.7dB higher than that of the low-noise amplifier in the related technology. This difference is very significant in terms of radio frequency performance. The noise figure of the low-noise amplifier circuit 100 in this embodiment is about 0.03dB lower than that of the low-noise amplifier in the related technology.

[0063] Compared with related technologies, the low-noise amplifier circuit 100 of this embodiment adds an impedance adjustment circuit 4 at the output terminal of the common-source amplifier circuit 2, which, together with the source-end degradation circuit 3, is used to adjust the input impedance of the low-noise amplifier circuit 100. The impedance adjustment circuit 4 is defined to include at least one first capacitor. The first terminals of all the first capacitors are connected together and connected to the output terminal of the common-source amplifier circuit 2. The second terminals of all the first capacitors are connected together and grounded. In this way, the inductance value of the source-end degradation inductor LS in the source-end degradation circuit 3 can be designed to be very small, and there is no need to continuously change its inductance value. Only the capacitance value of the first capacitor in the impedance adjustment circuit 4 needs to be changed to realize the transformation of the input impedance of the low-noise amplifier circuit 100. This allows the low-noise amplifier circuit 100 to better match with modules or external circuits, or to realize the switching of different gain levels, and improves the integration of the low-noise amplifier circuit 100, so that its overall area is not wasted too much. Meanwhile, the low-noise amplifier circuit 100 of this embodiment has strong compatibility, is suitable for different design architectures of low-noise amplifier circuits 100, can reduce the size of the external input matching inductor, achieve lower noise performance, and can be used simultaneously with optimization methods of related technologies.

[0064] Furthermore, SOI (Silicon-On-Insulator) chips in related technologies often employ inductor area compression to improve integration, which leads to a decrease in the inductor's Q value and ultimately degrades the RF performance of the low-noise amplifier. Since capacitors typically have a Q value greater than 200, while inductors generally have a Q value less than 30, this embodiment improves the RF performance of the low-noise amplifier circuit 100 by adding an impedance adjustment circuit 4 containing a first capacitor to adjust the input impedance.

[0065] Example 2 This embodiment provides a radio frequency (RF) front-end module, which includes the low-noise amplifier circuit 100 from Embodiment 1. Since the RF front-end module in this embodiment includes the low-noise amplifier circuit 100 from Embodiment 1, it can also achieve the same technical effects as the low-noise amplifier circuit 100 from Embodiment 1, and will not be described in detail here.

[0066] It should be noted that the various embodiments described above with reference to the accompanying drawings are merely illustrative of the present invention and not intended to limit its scope. Those skilled in the art should understand that any modifications or equivalent substitutions made to the present invention without departing from its spirit and scope should be included within the scope of the present invention. Furthermore, unless the context otherwise requires, words appearing in the singular include those in the plural, and vice versa. Additionally, unless specifically stated otherwise, all or part of any embodiment may be used in conjunction with all or part of any other embodiment.

Claims

1. A low noise amplifier circuit, characterized by, The low-noise amplifier circuit includes an input matching adjustment circuit, a common-source amplifier circuit, a source-end degradation circuit, an impedance adjustment circuit, a common-gate amplifier circuit, an interstage matching circuit, an input-output feedback circuit, an output matching adjustment circuit, and an output attenuation circuit. The input terminal of the input matching adjustment circuit is used to receive radio frequency signals; The common-source amplifier circuit includes a first field-effect transistor (FET), the gate of which serves as the input terminal of the common-source amplifier circuit and is used to connect to a first bias voltage and the output terminal of the input matching adjustment circuit, respectively. The drain of the first FET serves as the output terminal of the common-source amplifier circuit. The source degradation circuit includes at least one source degradation inductor, the first terminals of all the source degradation inductors are respectively connected to the source of the first field-effect transistor, and the second terminals of all the source degradation inductors are respectively grounded; The impedance adjustment circuit includes at least one first capacitor; the first terminals of all the first capacitors are connected together and then connected to the output terminal of the common source amplifier circuit, and the second terminals of all the first capacitors are connected together and then grounded; the impedance adjustment circuit and the source degradation circuit are used together to adjust the input impedance of the low noise amplifier circuit. The first input terminal of the common-gate amplifier circuit is used to connect to the second bias voltage, and the second input terminal of the common-gate amplifier circuit is connected to the output terminal of the common-source amplifier circuit. The input terminal of the interstage matching circuit is connected to the output terminal of the common-source amplifier circuit, and the output terminal of the interstage matching circuit is grounded. The input terminal of the input-output feedback circuit is connected to the input terminal of the common-source amplifier circuit, and the output terminal of the input-output feedback circuit is connected to the output terminal of the common-gate amplifier circuit. The input terminal of the output matching adjustment circuit is used to connect to the operating voltage, and the output terminal of the output matching adjustment circuit is connected to the output terminal of the common-gate amplifier circuit. The input terminal of the output attenuation circuit is connected to the output terminal of the common-gate amplifier circuit, and the output terminal of the output attenuation circuit is used to output radio frequency signals. The impedance adjustment circuit includes a plurality of first capacitors; the impedance adjustment circuit also includes a plurality of single-pole single-throw switches; the number of first capacitors is defined as n, and the number of single-pole single-throw switches is n-1, where n is a positive integer greater than or equal to 2; One of the first capacitors is connected to the control terminal of all the single-pole single-throw switches and is connected to the output terminal of the common-source amplifier circuit. The first terminal of each of the remaining first capacitors is connected to the output terminal of one of the single-pole single-throw switches. The second terminals of all the first capacitors are connected to each other and are grounded together.

2. The low noise amplification circuit of claim 1, wherein, The common-source amplifier circuit further includes a first resistor; the first end of the first resistor is connected to the gate of the first field-effect transistor, and the second end of the first resistor is used to connect to a first bias voltage.

3. The low noise amplification circuit of claim 1, wherein, The common-gate amplifier circuit includes a second resistor and a second field-effect transistor; The first terminal of the second resistor serves as the first input terminal of the common-gate amplifier circuit. The gate of the second field-effect transistor is connected to the second terminal of the second resistor, the source of the second field-effect transistor serves as the second input terminal of the common-gate amplifier circuit, and the drain of the second field-effect transistor serves as the output terminal of the common-gate amplifier circuit.

4. The low-noise amplifier circuit as described in claim 1, characterized in that, The low-noise amplifier circuit also includes a second capacitor; the first terminal of the second capacitor is connected to the input terminal of the output matching adjustment circuit, and the second terminal of the second capacitor is grounded.

5. The low-noise amplifier circuit as described in claim 1, characterized in that, The low-noise amplifier circuit also includes a third capacitor; the first end of the third capacitor is connected to the output terminal of the common-gate amplifier circuit and the output terminal of the output matching adjustment circuit, respectively, and the second end of the third capacitor is connected to the input terminal of the output attenuation circuit.

6. A radio frequency front-end module, characterized in that, The radio frequency front-end module includes the low-noise amplifier circuit as described in any one of claims 1 to 5.

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