Low noise amplifier

Abstract

This invention relates to the field of wireless communication technology and provides a low-noise amplifier, which includes an input matching circuit, a bypass circuit, and an amplification circuit. The low-noise amplifier also includes a second control unit, an output matching circuit, and an output attenuation circuit. The output matching circuit includes a first capacitor, a second capacitor, a third capacitor, a first adjustable resistor, a first switch, a second switch, a first inductor, and a second inductor. When the radio frequency signal passing through the output matching circuit is within a first operating frequency band, the first switch is open and the second switch is open. When the radio frequency signal passing through the output matching circuit is within a second operating frequency band, the first switch is closed and the second switch is open. When the radio frequency signal passing through the output matching circuit is within a third operating frequency band, the first switch is closed and the second switch is closed. The frequency bands gradually decrease from the first operating frequency band to the third operating frequency band. The low-noise amplifier of this invention has low power consumption, small area, and good bandpass mode return loss.

Description

Technical Field

[0001] This invention relates to the field of wireless communication technology, and more particularly to a low-noise amplifier. Background Technology

[0002] With the rapid iteration of 5G communication technology, terminal devices are experiencing a leap in demand for core communication performance. Higher transmission rates, wider transmission bandwidth, and lower latency have become key indicators, directly determining user experience and the scope for industry application expansion. However, these high-performance requirements have directly driven the high complexity of RF front-end module architecture, significantly increasing the integration of various active and passive components, which in turn has led to a sharp increase in power consumption issues.

[0003] Constrained by limitations in battery technology, the battery capacity of mobile terminals such as smartphones is unlikely to achieve a breakthrough increase in the short term, making power consumption control a core bottleneck restricting the improvement of 5G terminal battery life. Among these, the low-noise amplifier, as a key module in the radio frequency front-end that is always in operation, generates a significant proportion of power consumption during long-term operation, becoming an important factor affecting the overall energy consumption performance of the terminal, making its low-power optimization increasingly urgent.

[0004] Currently, most mainstream low-noise amplifiers on the market adopt a common-source, common-gate topology, with the output matching stage using a traditional LC matching scheme. For wideband applications in the sub-3GHz band, the industry typically achieves wideband adaptation by switching the output matching capacitor. However, practice shows that when power consumption decreases to a certain threshold, this classic architecture faces an irreconcilable performance contradiction, disrupting the balance between gain, noise figure (NF), and input reflection coefficient (S11), making it impossible to simultaneously meet the stringent requirements of practical applications. This easily leads to higher overall power consumption in the low-noise amplifier. Summary of the Invention

[0005] In view of the shortcomings of the prior art, the present invention proposes a low-noise amplifier to solve the problems of low gain and high power consumption of existing low-noise amplifiers.

[0006] To solve the above-mentioned technical problems, the present invention adopts the following technical solution:

[0007] This invention provides a low-noise amplifier, which includes an input matching circuit, a bypass circuit, and an amplification circuit. The input terminal of the input matching circuit is used to receive a radio frequency signal. The output terminal of the input matching circuit is connected to the input terminal of the bypass circuit and the input terminal of the amplification circuit, respectively. The output terminal of the bypass circuit is connected to the output terminal of the amplification circuit. The low-noise amplifier also includes a first control unit and a second control unit. The first control unit is used to control the switching on or off of the bypass circuit. The second control unit is used to control the switching on or off of the amplification circuit.

[0008] The bypass circuit includes a first control unit, which controls the switching on or off of the bypass circuit; the low-noise amplifier also includes a second control unit, an output matching circuit, and an output attenuation circuit; the second control unit controls the switching on or off of the amplification circuit; the input terminal of the output matching circuit is connected to the output terminal of the amplification circuit, and the output terminal of the output matching circuit is connected to the input terminal of the output attenuation circuit; the radio frequency signal is impedance matched by the output matching circuit, and then output after controllable amplitude attenuation by the output attenuation circuit.

[0009] The output matching circuit includes a first capacitor, a second capacitor, a third capacitor, a first adjustable resistor, a first switch, a second switch, a first inductor, and a second inductor.

[0010] The first terminal of the first inductor serves as the input terminal of the output matching circuit. The first terminal of the first inductor is connected to the first terminal of the second capacitor, the first terminal of the third capacitor, and the first terminal of the first adjustable resistor. The second terminal of the third capacitor is grounded after being connected in series with the second switch. The second terminal of the second capacitor is connected to the control terminal of the first switch. The output terminal of the first switch is connected to the input terminal of the output attenuation circuit. The second terminal of the first inductor is connected to the first terminal of the second inductor and forms a coupling. The second terminal of the first inductor is also connected to the first terminal of the first capacitor, and the second terminal of the first capacitor serves as the output terminal of the output matching circuit. The second terminal of the second inductor is connected to the second terminal of the first adjustable resistor and is used to connect to the power supply.

[0011] When the radio frequency signal passing through the output matching circuit is within the first operating frequency band, the first switch is open and the second switch is open.

[0012] When the radio frequency signal passing through the output matching circuit is within the second operating frequency band, the first switch is closed and the second switch is open;

[0013] When the radio frequency signal passing through the output matching circuit is within the third operating frequency band, the first switch closes and the second switch closes.

[0014] The frequencies of the first operating frequency band to the third operating frequency band gradually decrease.

[0015] Preferably, the first inductor and the second inductor are arranged in a nested stacked structure.

[0016] Preferably, the first operating frequency band is 2.3-2.7 GHz, the second operating frequency band is 1.8-2.2 GHz, and the third operating frequency band is 1.4-1.6 GHz.

[0017] Preferably, the low-noise amplifier further includes a fourth capacitor, the first end of which is used to connect to the power supply, and the second end of which is grounded.

[0018] Preferably, the low-noise amplifier further includes a fifth capacitor, the first end of which is connected to the output terminal of the first control unit, and the second end of which is connected to the first end of the first inductor.

[0019] Preferably, the first control unit includes a third switch and a fourth switch. The control terminal of the third switch serves as the input terminal of the first control unit, the output terminal of the third switch is connected to the control terminal of the fourth switch, the output terminal of the fourth switch is grounded, and the output terminal of the third switch also serves as the output terminal of the first control unit.

[0020] Preferably, the amplification circuit includes a protection unit, a fifth switch, a capacitor adjustment unit, an inductor adjustment unit, an attenuation suppression unit, a first MOSFET, and a second MOSFET;

[0021] The input terminal of the protection unit serves as the input terminal of the amplifier circuit. The output terminal of the protection unit is connected to the input terminal of the second control unit. The control terminal of the fifth switch is connected to the input terminal of the protection unit, and the output terminal of the fifth switch is connected to the output terminal of the protection unit and grounded. The fifth switch is used to adjust the isolation of the amplifier circuit. The output terminal of the second control unit is connected to the first terminal of the capacitor adjustment unit and the gate of the first MOS transistor. The second terminal of the capacitor adjustment unit is connected to the source of the first MOS transistor and the first terminal of the inductor adjustment unit, and the second terminal of the inductor adjustment unit is grounded. The drain of the first MOS transistor is connected to the first terminal of the attenuation suppression unit and the source of the second MOS transistor. The attenuation suppression unit... The second terminal is grounded; the gates of the first MOS transistor and the second MOS transistor are also used to connect to external logic control circuits, which provide control signals to the gates of the first MOS transistor and the second MOS transistor respectively; the drain of the second MOS transistor serves as the output terminal of the amplifier circuit; the protection unit is used to protect and output the RF signal output by the input matching circuit; the capacitor adjustment unit is used to adjust the capacitor size to adjust the gain; the inductor adjustment unit is used to adjust the source inductance of the first MOS transistor to improve the gain and suppress noise; the attenuation suppression unit is used to provide feedback adjustment for the gain output of different levels implemented by the amplifier circuit to improve the linearity of the amplifier circuit at different gain output levels.

[0022] Preferably, the protection unit includes a first diode and a second diode; the control terminal of the fifth switch serves as the input terminal of the protection unit, and the output terminal of the fifth switch is connected to the negative terminal of the first diode and the positive terminal of the second diode and grounded; the negative terminal of the first diode is connected to the positive terminal of the second diode and serves as the output terminal of the protection unit.

[0023] The low-noise amplifier also includes a third diode and a fourth diode, which are used to provide overvoltage protection for the amplifier circuit;

[0024] The capacitor adjustment unit includes an adjustable sixth capacitor; the positive terminal of the third diode is connected to the negative terminal of the fourth diode and the first terminal of the sixth capacitor, respectively, and serves as the first terminal of the capacitor adjustment unit; the negative terminal of the third diode is connected to the positive terminal of the fourth diode and the second terminal of the sixth capacitor, respectively, and serves as the second terminal of the capacitor adjustment unit.

[0025] The attenuation suppression unit includes a seventh capacitor and a second adjustable resistor; the first end of the seventh capacitor serves as the first end of the attenuation suppression unit, and the second end of the seventh capacitor is connected to the first end of the second adjustable resistor, with the second end of the second adjustable resistor serving as the second end of the attenuation suppression unit.

[0026] The inductance adjustment unit includes an adjustable third inductor and a sixth switch; the first end of the third inductor serves as the first end of the inductance adjustment unit, the second end of the third inductor is connected to the control end of the sixth switch, and the output end of the sixth switch serves as the second end of the inductance adjustment unit.

[0027] Preferably, the low-noise amplifier further includes an eighth capacitor and a first resistor; the first end of the eighth capacitor is connected to the output terminal of the second control unit, and the second end of the eighth capacitor is connected to the first end of the first resistor and the gate of the first MOS transistor respectively; the second end of the first resistor is used to connect to the external logic control circuit.

[0028] Preferably, the low-noise amplifier further includes a ninth capacitor and a second resistor; the first end of the second resistor is used to connect to the external logic control circuit, the second end of the second resistor is connected to the first end of the ninth capacitor and the gate of the second MOS transistor respectively, and the second end of the ninth capacitor is grounded.

[0029] Compared with related technologies, in the embodiments of the present invention, the input terminal of the output matching circuit of the bypass circuit is used as the input terminal of the bypass circuit, the output terminal of the input matching circuit is connected to the input terminal of the output attenuation circuit, and the output terminal of the output attenuation circuit is used to output the radio frequency signal; the radio frequency signal received by the output matching circuit is impedance matched, and then output after controllable amplitude attenuation by the output attenuation circuit; the first terminal of the first inductor of the output matching circuit is used as the input terminal of the output matching circuit, the first terminal of the first inductor is connected to the first terminal of the second capacitor, the first terminal of the third capacitor and the first terminal of the first adjustable resistor, the second terminal of the third capacitor is grounded after being connected in series with the second switch, the second terminal of the second capacitor is connected to the control terminal of the first switch, and the output terminal of the first switch is connected to the input terminal of the output attenuation circuit; the first The second end of the inductor is connected to the first end of the second inductor and forms a coupling; the second end of the first inductor is also connected to the first end of the first capacitor; when the RF signal passing through the output matching circuit is within the first operating frequency band, the first switch is open and the second switch is open; when the RF signal passing through the output matching circuit is within the second operating frequency band, the first switch is closed and the second switch is open; when the RF signal passing through the output matching circuit is within the third operating frequency band, the first switch is closed and the second switch is closed; wherein, the frequency gradually decreases from the first operating frequency band to the third operating frequency band; multiple frequency bands can be operated by different switch controls, and the gain can be improved under a fixed current without affecting the noise, thereby making the low-noise amplifier have low overall power consumption, small layout area, and good return loss in BP mode (bandpass mode). Attached Figure Description

[0030] 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:

[0031] Figure 1 A circuit diagram of a low-noise amplifier provided for an embodiment of the present invention;

[0032] Figure 2 This is a schematic diagram of the structure of the first inductor of a low-noise amplifier provided in an embodiment of the present invention.

[0033] Among them, 100 is a low-noise amplifier, 1 is an input matching circuit, 2 is an amplification circuit, 21 is a protection unit, 22 is a capacitor adjustment unit, 23 is an inductor adjustment unit, 24 is an attenuation suppression unit, 3 is a bypass circuit, 4 is a first control unit, 5 is a second control unit, 6 is an output matching circuit, and 7 is an output attenuation circuit. Detailed Implementation

[0034] 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.

[0035] 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.

[0036] 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.

[0037] Please see Figures 1-2 As shown, this embodiment of the invention provides a low-noise amplifier 100, which includes an input matching circuit 1, a bypass circuit 3, and an amplifier circuit 2. The input terminal of the input matching circuit 1 is used to receive a radio frequency (RF) signal. The output terminal of the input matching circuit 1 is connected to both the input terminal of the bypass circuit 3 and the input terminal of the amplifier circuit 2. The output terminal of the bypass circuit 3 is connected to the output terminal of the amplifier circuit 2 and is used to output the RF signal. The bypass circuit 3 includes a first control unit 4. The input terminal of the first control unit 4 is connected to the output terminal of the input matching circuit 1, and the output terminal of the first control unit 4 is connected to the output terminal of the amplifier circuit. The first control unit 4 is used to control the conduction or deactivation of the bypass circuit 3. The low-noise amplifier 100 also includes a second control unit 5, an output matching circuit 6, and an output attenuation circuit 7. The second control unit 5 is used to control the conduction or deactivation of the amplifier circuit 2. Optionally, the input matching circuit 1 is a fourth inductor L4, used to achieve input impedance matching. The signal input terminal is RFIN, and the signal output terminal is ROUT1.

[0038] The input terminal of the output matching circuit 6 is connected to the output terminal of the amplifier circuit 2, and the output terminal of the output matching circuit 6 is connected to the input terminal of the output attenuation circuit 7. The radio frequency signal is impedance matched by the output matching circuit 6, and then output after controllable amplitude attenuation by the output attenuation circuit 7.

[0039] The output matching circuit 6 includes a first capacitor C1, a second capacitor C2, a third capacitor C3, a first adjustable resistor R1, a first switch S1, a second switch S2, a first inductor L1, and a second inductor L2. The first terminal of the first inductor L1 serves as the input terminal of the output matching circuit 6. The first terminal of the first inductor L1 is connected to the first terminals of the second capacitor C2, the third capacitor C3, and the first adjustable resistor R1. The second terminal of the third capacitor C3 is grounded after being connected in series with the second switch S2. The second terminal of the second capacitor C2 is connected to the control terminal of the first switch S1. The output terminal of the first switch S1 is connected to the input terminal of the output attenuation circuit 7. The second terminal of the first inductor L1 is connected to and coupled to the first terminal of the second inductor L2. The second terminal of the first inductor L1 is also connected to the first terminal of the first capacitor C1, and the second terminal of the first capacitor C1 serves as the output terminal of the output matching circuit 6. The second terminal of the second inductor L2 is connected to the second terminal of the first adjustable resistor R1 and is used to connect to the power supply VDD.

[0040] When the radio frequency signal passing through the output matching circuit 6 is within the first operating frequency band, the first switch S1 is open, and the second switch S2 is open. Specifically, at this time, the matching network retains only the basic core branch, whose equivalent parameters correspond to a matching frequency band that exactly covers 2.3-2.7GHz. When the first switch S1 is open, the additional branch it controls is disconnected, preventing the parameters of this branch from interfering with high-frequency signal matching, and ensuring that the low-noise amplifier 100 has the lowest noise figure and stable gain within the 2.3-2.7GHz range.

[0041] When the radio frequency signal passing through the output matching circuit 6 is within the second operating frequency band, the first switch S1 closes and the second switch S2 opens. Specifically, after the first switch S1 closes, the additional branch it controls is connected to the matching network, increasing the equivalent capacitance of the entire network (or fine-tuning the equivalent inductance), causing the resonant frequency / adaptation frequency band of the matching network to shift to a lower frequency, precisely covering 1.8-2.2GHz. At this time, the second switch S2 opens to prevent its branch parameters from further changing the matching state, ensuring optimal impedance matching within this frequency band.

[0042] When the radio frequency signal passing through the output matching circuit 6 is within the third operating frequency band, the first switch S1 closes and the second switch S2 closes. Specifically, the closure of the first switch S1 shifts the matching frequency band to a lower frequency. After the second switch S2 closes, the secondary additional branch it controls is further connected, increasing the equivalent capacitance of the matching network again. The matching frequency band corresponding to the equivalent parameters continues to shift to an even lower frequency, ultimately covering 1.4-1.6 GHz. The closure of both switches achieves matching adaptation to a lower frequency band by superimposing additional parameters, ensuring efficient signal transmission and controllable noise in this frequency band.

[0043] The frequencies of the first to the third operating frequency bands gradually decrease. Multiple frequency bands can be operated through different switch controls, increasing gain without affecting noise at a fixed current. This results in low power consumption, a small layout area, and good return loss in BP mode (bandpass mode) for the low-noise amplifier 100. Furthermore, wideband matching of 1.4-2.7 GHz can be achieved with only two switches, two control lines, and three capacitors, significantly reducing the output matching area. The nested coupling of inductors allows the radiated energy of one coil to be absorbed by another, improving energy utilization. Looking from the output of amplifier circuit 2 towards the signal output, the inductance connected in parallel to AC ground increases, further reducing AC energy loss. This significantly improves the gain at a fixed power, providing more margin for power consumption and noise figure, which is key to the low current capability of this structure. Additionally, for bypass matching, lower frequencies require larger common-gate drain inductors to optimize network matching and Q-factor (quality factor). This structure also provides a large inductance value (L1+L2) at lower frequencies.

[0044] In this embodiment, the first inductor L1 and the second inductor L2 are arranged in a nested stacked structure. By stacking the first inductor L1 and the second inductor L2 and using a nested structure layout, not only can the layout area be saved, but the gain can also be improved under a fixed current without affecting the noise.

[0045] In this embodiment, the first operating frequency band is 2.3-2.7GHz, the second operating frequency band is 1.8-2.2GHz, and the third operating frequency band is 1.4-1.6GHz.

[0046] In this embodiment, the low-noise amplifier 100 further includes a fourth capacitor C4. The first terminal of the fourth capacitor C4 is connected to the power supply VDD, and the second terminal of the fourth capacitor C4 is grounded. By connecting the fourth capacitor C4 in parallel with the second inductor L2 and then connecting it to the power supply VDD, power supply noise can be filtered out, interference coupling can be reduced, the power supply voltage can be stabilized, gain attenuation can be avoided, reverse coupling of radio frequency signals can be suppressed, and impedance matching can be optimized.

[0047] In this embodiment, the low-noise amplifier 100 further includes a fifth capacitor C5. The first end of the fifth capacitor C5 is connected to the output terminal of the first control unit 4, and the second end of the fifth capacitor C5 is connected to the first end of the first inductor L1. The fifth capacitor C5 can serve as a DC blocking device.

[0048] In this embodiment, the first control unit 4 includes a third switch S3 and a fourth switch S4. The control terminal of the third switch S3 serves as the input terminal of the first control unit 4, and the output terminal of the third switch S3 is connected to the control terminal of the fourth switch S4. The output terminal of the fourth switch S4 is grounded, and the output terminal of the third switch S3 also serves as the output terminal of the first control unit 4. When the third switch S3 is turned on, the bypass circuit 3 can be turned on to achieve bypass mode.

[0049] In this embodiment, the amplification circuit 2 includes a protection unit 21, a fifth switch S5, a capacitor adjustment unit 22, an inductor adjustment unit 23, an attenuation suppression unit 24, a first MOSFET M1, and a second MOSFET M2. The second control unit 5 is a seventh switch S7. The control terminal of the seventh switch S7 is connected to the output terminal of the protection unit 21, and the output terminal of the seventh switch S7 is connected to the gate of the first MOSFET M1.

[0050] Specifically, a common-source, common-gate amplification structure is formed by the first MOSFET M1 and the second MOSFET M2 to amplify the signal of the circuit. The input terminal of the protection unit 21 serves as the input terminal of the amplification circuit 2, and the output terminal of the protection unit 21 is connected to the input terminal of the second control unit 5. The control terminal of the fifth switch S5 is connected to the input terminal of the protection unit 21, and the output terminal of the fifth switch S5 is connected to the output terminal of the protection unit 21 and grounded. The fifth switch S5 is used to adjust the isolation of the amplification circuit 2. The output terminal of the second control unit 5 is connected to the first terminal of the capacitor adjustment unit 22 and the gate of the first MOSFET M1, respectively. The second terminal of the capacitor adjustment unit 22 is connected to the source of the first MOSFET M1 and the first terminal of the inductor adjustment unit 23, respectively, and the second terminal of the inductor adjustment unit 23 is grounded. The drain of the first MOSFET M1 is connected to the first terminal of the attenuation suppression unit 24 and the source of the second MOSFET M2, respectively, and the second terminal of the attenuation suppression unit 24 is grounded. The gates of the first MOSFET M1 and the second MOSFET M2 are also used to connect to external logic control circuits, which are respectively... The gates of the first MOS transistor M1 and the second MOS transistor M2 provide control signals; the drain of the second MOS transistor M2 serves as the output terminal of the amplifier circuit 2; the protection unit 21 is used to protect and output the RF signal output by the input matching circuit 1; the capacitor adjustment unit 22 is used to adjust the capacitor size to adjust the gain; the inductor adjustment unit 23 is used to adjust the source inductance of the first MOS transistor M1 to improve the gain and suppress noise; the attenuation suppression unit 24 is used to provide feedback adjustment for the gain output of different levels implemented by the amplifier circuit 2 to improve the linearity of the amplifier circuit 2 at different gain output levels.

[0051] In this embodiment, the bypass mode and amplification mode are switched through the combined action of the third switch S3, the fourth switch S4, and the sixth switch S6, thereby achieving switching between various gain levels and balancing performance. The first inductor L1 and the second inductor L2 form a nested tap structure, and the switching between 1.4-2.7GHz matching is achieved by opening and closing the first switch S1 and the second switch S2.

[0052] In this embodiment, the protection unit 21 includes a first diode D1, a second diode D2, and a fifth switch S5. The control terminal of the fifth switch S5 serves as the input terminal of the protection unit 21, and the output terminal of the fifth switch S5 is connected to the negative terminal of the first diode D1 and the positive terminal of the second diode D2, respectively, and grounded. The negative terminal of the first diode D1 and the positive terminal of the second diode D2 are connected and serve as the output terminal of the protection unit 21. By connecting the first diode D1 and the second diode D2 in parallel with the fifth switch S5, the protection unit 21, which integrates limiting and auxiliary matching control, is protected. Simultaneously, the switches optimize the input matching performance under small signals. Optimizing input matching with the switches reduces small signal loss.

[0053] The low-noise amplifier 100 also includes a third diode D3 and a fourth diode D4, which provide overvoltage protection for the amplifier circuit 2. This enables high-power signal limiting protection.

[0054] The capacitor adjustment unit 22 includes an adjustable sixth capacitor C6; the positive terminal of the third diode D3 is connected to the negative terminal of the fourth diode D4 and the first terminal of the sixth capacitor C6, serving as the first terminal of the capacitor adjustment unit 22; the negative terminal of the third diode D3 is connected to the positive terminal of the fourth diode D4 and the second terminal of the sixth capacitor C6, serving as the second terminal of the capacitor adjustment unit 22. The third diode D3 and the fourth diode D4 provide circuit protection, while the adjustable sixth capacitor C6 allows for capacitance adjustment, facilitating input matching and reducing power consumption.

[0055] The attenuation suppression unit 24 includes a seventh capacitor C7 and a second adjustable resistor R2. The first terminal of the seventh capacitor C7 serves as the first terminal of the attenuation suppression unit 24, and the second terminal of the seventh capacitor C7 is connected to the first terminal of the second adjustable resistor R2. The second terminal of the second adjustable resistor R2 serves as the second terminal of the attenuation suppression unit 24. The RC attenuation between the common source and common gate stages of the first MOSFET M1 and the second MOSFET M2 can be adjusted via the seventh capacitor C7 and the second adjustable resistor R2.

[0056] The inductor adjustment unit 23 includes an adjustable third inductor L3 and a sixth switch S6. The first end of the third inductor L3 serves as the first end of the inductor adjustment unit 23, the second end of the third inductor L3 is connected to the control terminal of the sixth switch S6, and the output terminal of the sixth switch S6 serves as the second end of the inductor adjustment unit 23. Through the combined use of six attenuation methods—the source-switchable third inductor L3, the switchable area first MOSFET M1, the switchable common-source common-gate inter-stage attenuation suppression unit 24, the switchable common-gate drain first adjustable resistor R1, output attenuation, and bypass path—a balance of various parameters is achieved within the gain range from -12dB to 21dB.

[0057] In this embodiment, the low-noise amplifier 100 further includes an eighth capacitor C8 and a first resistor R11; the first end of the eighth capacitor C8 is connected to the output terminal of the second control unit 5, and the second end of the eighth capacitor C8 is connected to the first end of the first resistor R11 and the gate of the first MOS transistor M1; the second end of the first resistor R11 is used to connect to the external logic control circuit (VGCG). The eighth capacitor C8 and the first resistor R11 are used to protect the circuit.

[0058] In this embodiment, the low-noise amplifier 100 further includes a ninth capacitor C9 and a second resistor R12; the first end of the second resistor R12 is connected to the external logic control circuit (VGCS), and the second end of the second resistor R12 is connected to the first end of the ninth capacitor C9 and the gate of the second MOS transistor M2, respectively. The second end of the ninth capacitor C9 is grounded. The ninth capacitor C9 and the second resistor R12 are used to protect the circuit.

[0059] 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, comprising an input matching circuit, a bypass circuit, and an amplification circuit, wherein the input terminal of the input matching circuit is used to receive a radio frequency signal, the output terminal of the input matching circuit is connected to the input terminal of the bypass circuit and the input terminal of the amplification circuit respectively, and the output terminal of the bypass circuit is connected to the output terminal of the amplification circuit; characterized in that, The bypass circuit includes a first control unit, which controls the opening or closing of the bypass circuit; the low-noise amplifier also includes a second control unit, an output matching circuit, and an output attenuation circuit. The second control unit is used to control the conduction or shutdown of the amplifier circuit; the input terminal of the output matching circuit is connected to the output terminal of the amplifier circuit, and the output terminal of the output matching circuit is connected to the input terminal of the output attenuation circuit. The radio frequency signal is impedance matched by the output matching circuit and then output after controllable amplitude attenuation by the output attenuation circuit. The output matching circuit includes a first capacitor, a second capacitor, a third capacitor, a first adjustable resistor, a first switch, a second switch, a first inductor, and a second inductor. The first terminal of the first inductor serves as the input terminal of the output matching circuit. The first terminal of the first inductor is connected to the first terminal of the second capacitor, the first terminal of the third capacitor, and the first terminal of the first adjustable resistor. The second terminal of the third capacitor is grounded after being connected in series with the second switch. The second terminal of the second capacitor is connected to the control terminal of the first switch. The output terminal of the first switch is connected to the input terminal of the output attenuation circuit. The second terminal of the first inductor is connected to the first terminal of the second inductor and forms a coupling. The second terminal of the first inductor is also connected to the first terminal of the first capacitor, and the second terminal of the first capacitor serves as the output terminal of the output matching circuit. The second terminal of the second inductor is connected to the second terminal of the first adjustable resistor and is used to connect to the power supply. When the radio frequency signal passing through the output matching circuit is within the first operating frequency band, the first switch is open and the second switch is open. When the radio frequency signal passing through the output matching circuit is within the second operating frequency band, the first switch is closed and the second switch is open; When the radio frequency signal passing through the output matching circuit is within the third operating frequency band, the first switch closes and the second switch closes. The frequencies of the first operating frequency band to the third operating frequency band gradually decrease.

2. The low-noise amplifier according to claim 1, characterized in that, The first inductor and the second inductor are arranged in a nested stacked structure.

3. The low-noise amplifier according to claim 1, characterized in that, The first operating frequency band is 2.3-2.7 GHz, the second operating frequency band is 1.8-2.2 GHz, and the third operating frequency band is 1.4-1.6 GHz.

4. The low-noise amplifier according to claim 1, characterized in that, The low-noise amplifier also includes a fourth capacitor, the first end of which is connected to the power supply, and the second end of which is grounded.

5. The low-noise amplifier according to claim 1, characterized in that, The low-noise amplifier further includes a fifth capacitor, the first end of which is connected to the output terminal of the first control unit, and the second end of which is connected to the first end of the first inductor.

6. The low-noise amplifier according to claim 5, characterized in that, The first control unit includes a third switch and a fourth switch. The control terminal of the third switch serves as the input terminal of the first control unit, the output terminal of the third switch is connected to the control terminal of the fourth switch, the output terminal of the fourth switch is grounded, and the output terminal of the third switch also serves as the output terminal of the first control unit.

7. The low-noise amplifier according to claim 1, characterized in that, The amplifier circuit includes a protection unit, a fifth switch, a capacitor adjustment unit, an inductor adjustment unit, an attenuation suppression unit, a first MOSFET, and a second MOSFET. The input terminal of the protection unit serves as the input terminal of the amplifier circuit. The output terminal of the protection unit is connected to the input terminal of the second control unit. The control terminal of the fifth switch is connected to the input terminal of the protection unit. The output terminal of the fifth switch is connected to the output terminal of the protection unit and grounded. The fifth switch is used to adjust the isolation of the amplifier circuit. The output terminal of the second control unit is connected to the first terminal of the capacitor adjustment unit and the gate of the first MOS transistor, respectively. The second terminal of the capacitor adjustment unit is connected to the source of the first MOS transistor and the first terminal of the inductor adjustment unit, respectively. The second terminal of the inductor adjustment unit is grounded. The drain of the first MOS transistor is connected to the first terminal of the attenuation suppression unit and the source of the second MOS transistor, respectively. The second terminal of the attenuation suppression unit is grounded. The gates of the first MOS transistor and the second MOS transistor are also used to connect to an external logic control circuit, which provides control signals to the gates of the first MOS transistor and the second MOS transistor, respectively. The drain of the second MOS transistor serves as the output terminal of the amplifier circuit. The protection unit is used to protect and output the RF signal output by the input matching circuit. The capacitor adjustment unit is used to adjust the capacitance to adjust the gain; the inductor adjustment unit is used to adjust the source inductance of the first MOS transistor to improve the gain and suppress noise. The attenuation suppression unit is used to provide feedback adjustment for the gain output of the amplifier circuit at different levels, so as to improve the linearity of the amplifier circuit at different gain output levels.

8. The low-noise amplifier according to claim 7, characterized in that, The protection unit includes a first diode and a second diode; the control terminal of the fifth switch serves as the input terminal of the protection unit, and the output terminal of the fifth switch is connected to the negative terminal of the first diode and the positive terminal of the second diode and grounded; the negative terminal of the first diode is connected to the positive terminal of the second diode and serves as the output terminal of the protection unit. The low-noise amplifier also includes a third diode and a fourth diode, which are used to provide overvoltage protection for the amplifier circuit; The capacitor adjustment unit includes an adjustable sixth capacitor; the positive terminal of the third diode is connected to the negative terminal of the fourth diode and the first terminal of the sixth capacitor, respectively, and serves as the first terminal of the capacitor adjustment unit; the negative terminal of the third diode is connected to the positive terminal of the fourth diode and the second terminal of the sixth capacitor, respectively, and serves as the second terminal of the capacitor adjustment unit. The attenuation suppression unit includes a seventh capacitor and a second adjustable resistor; the first end of the seventh capacitor serves as the first end of the attenuation suppression unit, and the second end of the seventh capacitor is connected to the first end of the second adjustable resistor, with the second end of the second adjustable resistor serving as the second end of the attenuation suppression unit. The inductance adjustment unit includes an adjustable third inductor and a sixth switch; the first end of the third inductor serves as the first end of the inductance adjustment unit, the second end of the third inductor is connected to the control end of the sixth switch, and the output end of the sixth switch serves as the second end of the inductance adjustment unit.

9. The low-noise amplifier according to claim 7, characterized in that, The low-noise amplifier further includes an eighth capacitor and a first resistor; the first end of the eighth capacitor is connected to the output terminal of the second control unit, and the second end of the eighth capacitor is connected to the first end of the first resistor and the gate of the first MOS transistor respectively; the second end of the first resistor is used to connect to the external logic control circuit.

10. The low-noise amplifier according to claim 7, characterized in that, The low-noise amplifier further includes a ninth capacitor and a second resistor; the first end of the second resistor is used to connect to the external logic control circuit, the second end of the second resistor is connected to the first end of the ninth capacitor and the gate of the second MOS transistor respectively, and the second end of the ninth capacitor is grounded.

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