Low-noise amplification circuit and radio frequency system

Abstract

The invention relates to the technical field of electronic circuits, in particular to a low-noise amplification circuit and a radio frequency system. The low-noise amplification circuit at least comprises an amplification input circuit and an amplification output circuit, wherein at least one group of tail inductor structure is arranged in the amplification input circuit and the amplification output circuit; the first resonance circuit is of a closed structure, the first resonance circuit is in coupling connection with the tail inductor structure, and the first resonance circuit is used for discharging current generated by the tail inductor structure; the first resonance circuit at least comprises a secondary coil which is in coupling connection with a primary coil in the tail inductor structure; and the first end of the first capacitor module is electrically connected with the secondary coil. The invention provides a low-noise amplification circuit with higher working stability.

Description

Technical Field

[0001] The present application relates to the technical field of electronic circuits, and in particular to a low-noise amplifier circuit and a radio frequency system. Background Art

[0002] LNA (Low Noise Amplifier) ​​is a commonly used circuit in RF systems, used to amplify signals while maintaining low noise in the system. Low noise, gain, and linearity are the main indicators of RF systems. LNA plays a vital role in maintaining the overall low noise of RF systems. The commonly used LNA circuit is a low noise amplifier with source degeneration inductor.

[0003] However, in actual operation, the source degeneration inductance often generates parasitic oscillation with the parasitic capacitance in the circuit. The parasitic oscillation is relatively stable at low frequencies, but very obvious at high frequencies, which seriously affects the working stability of the circuit and causes abnormal LNA function.

[0004] Therefore, there is an urgent need for a low-noise amplifier with higher stability. Summary of the invention

[0005] In order to solve the above technical problems, a low-noise amplifier circuit and a radio frequency system are provided in an embodiment of the present application.

[0006] A first aspect of an embodiment of the present application provides a low-noise amplifier circuit, comprising at least:

[0007] An amplifying input circuit and an amplifying output circuit; wherein the amplifying input circuit and the amplifying output circuit have at least one set of tail inductance structures;

[0008] A first resonant circuit, wherein the first resonant circuit is a closed structure, the first resonant circuit is coupled to the tail inductance structure, and the first resonant circuit is used to discharge the current generated by the tail inductance structure; the first resonant circuit at least includes:

[0009] A secondary coil is coupled to the primary coil in the tail inductor structure;

[0010] A first capacitor module, wherein a first end of the first capacitor module is electrically connected to the secondary coil.

[0011] In an optional embodiment of the present application, the first resonant circuit further includes:

[0012] A first adjustable resistor, wherein a first end of the first adjustable resistor is electrically connected to a first end of the secondary coil, and a second end of the first adjustable resistor is electrically connected to a second end of the first capacitor module; wherein the secondary coil, the first capacitor module and the first adjustable resistor are electrically connected to each other to form a closed structure.

[0013] In an optional embodiment of the present application, the amplifying input circuit at least includes:

[0014] An electrostatic protection circuit, wherein an input end of the electrostatic protection circuit is used to receive a radio frequency signal to be amplified, and the electrostatic protection circuit is grounded;

[0015] A second capacitor module, wherein a first end of the second capacitor module is electrically connected to the output end of the electrostatic protection circuit, and a second end of the capacitor module is grounded;

[0016] A first electronic switch module, wherein a control end of the first electronic switch module is electrically connected to the second capacitor module and the bias voltage, a source end of the first electronic switch module is electrically connected to the amplifying output circuit, and a drain end of the first electronic switch module is electrically connected to the primary coil in the tail inductor structure.

[0017] In an optional embodiment of the present application, the first electronic switch module at least includes:

[0018] A first electronic switch device, wherein a gate of the first electronic switch device is electrically connected to the second capacitor module and a first bias voltage, and a drain of the first electronic switch device is electrically connected to the primary coil in the tail inductor structure;

[0019] A second electronic switch device, wherein the gate of the second electronic switch device is used to connect to a second bias voltage, the source of the second electronic switch is electrically connected to the amplifying output circuit, and the drain of the second electronic switch device is electrically connected to the source of the first electronic switch device.

[0020] In an optional embodiment of the present application, the amplification output circuit at least includes:

[0021] A second electronic switch module, wherein a gate of the second electronic switch module is used to receive an enable signal, and a drain of the second electronic switch module is electrically connected to the second capacitor module;

[0022] a second resonant circuit, wherein an input end of the second resonant circuit is electrically connected to a source of the second crystal module;

[0023] An output matching circuit, wherein the input end of the output matching circuit is electrically connected to the output end of the second resonant circuit, and the output matching circuit is used to perform frequency matching and gain adjustment on the signal output by the second resonant circuit and then output a target radio frequency signal.

[0024] In an optional embodiment of the present application, the output matching circuit at least includes:

[0025] at least two groups of capacitors connected in parallel, wherein a first end of the capacitor is electrically connected to an output end of the second resonant circuit;

[0026] a first attenuation device, wherein an input end of the first attenuation device is electrically connected to the second end of the capacitor device, and the first attenuation device and the capacitor device perform frequency matching and gain adjustment on a signal output by the second resonant circuit to the target radio frequency signal;

[0027] An output module, wherein an input end of the output module is electrically connected to an output end of the first attenuation device, and the output module is used to output the target radio frequency signal.

[0028] In an optional embodiment of the present application, the second resonant circuit at least includes: a second adjustable resistor, an adjustable capacitor and an inductor connected in parallel with each other.

[0029] In an optional embodiment of the present application, the low noise amplifier circuit further includes:

[0030] A second attenuation device, wherein an input end of the second attenuation device is electrically connected to the source of the second electronic switch module, and an output end of the second attenuation device is electrically connected to the second resonant device.

[0031] In an optional embodiment of the present application, the amplifying input circuit and the amplifying output circuit are both in multiple groups, corresponding to different radio frequency signals respectively.

[0032] In an optional embodiment of the present application, the tail inductor structure in the amplifier input circuit at least includes:

[0033] The primary coil;

[0034] A plurality of third electronic switch modules, wherein the gates of the third electronic switch modules are used to receive control signals, the sources of the third electronic switch modules are electrically connected to the primary coils respectively, and the drains of the third electronic switches are grounded.

[0035] A second aspect of the embodiments of the present application provides a radio frequency system, comprising at least:

[0036] A low noise amplifier circuit as described in any one of the above items.

[0037] The source degeneration inductance often produces a parasitic oscillation phenomenon with the parasitic capacitance in the circuit. The parasitic oscillation phenomenon is relatively stable at low frequencies, but is very obvious at high frequencies, which seriously affects the working stability of the circuit and causes abnormal functions of the low-noise amplifier circuit. The low-noise amplifier circuit provided in the embodiment of the present application is provided with a first resonant circuit, which is a grounded closed structure. The first resonant circuit at least includes a secondary coil and a first capacitor module. In the case of low frequencies, the first capacitor module is equivalent to an open circuit, and the first resonant circuit does not work, thereby maintaining the normal operation of the low-noise amplifier circuit at low frequencies; in the case of high frequencies, the first capacitor module is equivalent to being turned on to form an LC closed resonant circuit. Since the first resonant circuit is grounded, the frequency generated by the primary coil can be discharged to the ground in the case of high frequencies, thereby avoiding the generation of parasitic oscillation phenomena at high frequencies, thereby greatly improving the working stability of the low-noise amplifier circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0039] Figure 1 A schematic diagram of the structure of a low-noise amplifier circuit provided in an embodiment of the present application;

[0040] Figure 2 A schematic diagram of the structure of a low-noise amplifier circuit provided in an embodiment of the present application;

[0041] Figure 3 A schematic diagram of the structure of a low-noise amplifier circuit provided in an embodiment of the present application;

[0042] Figure 4 A schematic diagram of the structure of a low-noise amplifier circuit provided in an embodiment of the present application;

[0043] Figure 5 A comparison chart of simulation results of the low-noise amplifier circuit provided in the embodiment of the present application and the traditional low-noise amplifier circuit.

[0044] in:

[0045] 10. Low noise amplifier circuit;

[0046] 100, amplification input circuit; L1, primary coil; M4, third electronic switch module; 120, electrostatic protection circuit; 130, second capacitor module; 140, first electronic switch module; M1, first electronic switch device; M2, second electronic switch device;

[0047] 200, amplification output circuit; M3, second electronic switch module; 220, second resonant circuit; R2, second adjustable resistor; C2, adjustable capacitor; L2, inductor; 230, output matching circuit; 231, capacitor device; Att1, first attenuation device; 233, output module; Att2, second attenuation device;

[0048] 300, first resonant circuit; L3, secondary coil; C1, first capacitor module; R1, first adjustable resistor. DETAILED DESCRIPTION

[0049] In the process of implementing the present application, the applicant discovered that there is an urgent need for a low-noise amplifier with higher stability.

[0050] In view of the above problems, a low-noise amplifier circuit and a radio frequency system are provided in the embodiments of the present application. In order to make the purpose, technical solution and advantages of the present application clearer, a low-noise amplifier circuit and a radio frequency system of the present application are further described in detail below through embodiments and in combination with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0051] The serial numbers assigned to the components herein, such as "first", "second", etc., are only used to distinguish the objects described and do not have any order or technical meaning. The "connection" and "coupling" mentioned in this application, unless otherwise specified, include direct and indirect connections (couplings). In the description of this application, it should be understood that the orientation or position relationship indicated by the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc. are based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing this application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to this application.

[0052] In the present application, unless otherwise clearly specified and limited, a first feature being “above” or “below” a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being “above”, “above”, and “above” a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being “below”, “below”, and “below” a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0053] See also Figure 1 and Figure 2The embodiment of the present application provides a low-noise amplifier circuit 10, which at least includes: an amplifier input circuit 100, an amplifier output circuit 200 and a first resonant circuit 300, wherein:

[0054] See also Figure 2 , an amplifier input circuit 100 and an amplifier output circuit 200; wherein, the amplifier input circuit 100 and the amplifier output circuit 200 have at least one set of tail inductance structures; the amplifier input circuit 100 refers to a circuit for receiving, preliminarily amplifying and processing the signal RFin to be amplified, and the amplifier output circuit 200 refers to a circuit for performing secondary amplification and processing on the signal RFin to be amplified. The embodiment of the present application limits the specific forms of the amplifier input circuit 100 and the amplifier output circuit 200, and it is only necessary to realize the function of low-noise amplification of the signal RFin to be amplified. The tail inductor structure can be composed of one or more inductors, which can be grounded and together with the first resonant circuit 300 form a source-degenerated inductor network with obvious frequency characteristics. The source-degenerated inductor network can maintain a high Q value within the operating frequency range (the Q value of inductor L2, also known as the quality factor of inductor L2, is the main parameter for measuring inductor devices. It refers to the ratio of the inductive reactance presented by the inductor to its equivalent loss resistance when it works under an AC voltage of a certain frequency. The higher the Q value of the inductor, the smaller its loss and the higher the efficiency). The Q value decreases rapidly at high frequencies, thereby greatly improving the high-frequency stability of the low-noise amplifier circuit 10.

[0055] See also Figure 2 , the first resonant circuit 300 is a closed structure, the first resonant circuit 300 is coupled with the tail inductance structure, and the first resonant circuit 300 is used to discharge the current generated by the tail inductance structure; the first resonant circuit 300 at least includes: a secondary coil L3 and a first capacitor module C1, wherein: the secondary coil L3 is coupled with the primary coil L1 in the tail inductance structure; the secondary coil L3 and the above-mentioned primary coil L1 form a coupled inductance L2 pair, which are coupled and oscillate with each other. The first end of the first capacitor module C1 is electrically connected to the secondary coil L3. In an optional embodiment, the second end of the first capacitor module C1 is grounded to discharge the current generated by the tail inductance structure. The first capacitor module C1 can be composed of one or more series capacitors, and the capacitor has the characteristics of passing high frequencies and blocking low frequencies. That is, in the case of low frequency, the first capacitor module C1 is equivalent to an open circuit, and the first resonant circuit 300 does not work; in the case of high frequency, the first capacitor module C1 is equivalent to being turned on to form a closed LC resonant circuit. Since the first resonant circuit 300 is grounded, the frequency generated by the primary coil L1 can be discharged to the ground in the case of high frequency, but it does not work in the case of low frequency.

[0056] In the low-noise amplifier 10, the source degeneration inductance often forms a three-point oscillator with the parasitic capacitance in the circuit, thereby generating a parasitic oscillation phenomenon. The parasitic oscillation phenomenon is not obvious at low frequencies, but at high frequencies, the parasitic capacitance and parasitic inductance of the circuit begin to take effect, and oscillations often occur, which seriously affects the working stability of the circuit and causes abnormal functions of the low-noise amplifier circuit 10. The low-noise amplifier circuit 10 provided in the embodiment of the present application is provided with a first resonant circuit 300, which is a closed structure. The first resonant circuit 300 at least includes a secondary coil L3 and a first capacitor module C1. In the case of low frequency, the first capacitor module C1 is equivalent to an open circuit, and the first resonant circuit 300 does not work, thereby maintaining the normal operation of the low-noise amplifier circuit 10 at low frequency; in the case of high frequency, the first capacitor module C1 is equivalent to being turned on to form an RLC closed resonant circuit, and the resistor R1 is used to adjust the Q value of the resonant circuit and reduce the Q value of the resonant circuit. The resonant circuit composed of L3, C12, and R1 reduces the inductance and Q value of the primary coil L1 through mutual inductance, so that it presents the characteristics of small inductance and low Q value at high frequency, so that the circuit does not meet the starting conditions, thereby avoiding parasitic oscillation at high frequency, thereby greatly improving the working stability of the low-noise amplifier circuit 10.

[0057] Please continue to see Figure 2 and Figure 3 In an optional embodiment of the present application, the first resonant circuit 300 further includes: a first adjustable resistor R1, wherein:

[0058] The first end of the first adjustable resistor R1 is electrically connected to the first end of the secondary coil L3, and the second end of the first adjustable resistor R1 is electrically connected to the second end of the first capacitor module C1; wherein the secondary coil L3, the first capacitor module C1 and the first adjustable resistor R1 are electrically connected to each other to form a closed structure. The first adjustable resistor R1 is used to adjust the Q value of the secondary coil L3. The larger the resistance value of the first adjustable resistor R1, the lower the Q value of the secondary coil L3. The performance of the first resonant circuit 300 can be adaptively adjusted by the first adjustable resistor R1 to meet the requirements of different scenarios and improve the adaptability of the low-noise amplifier circuit 10 of the embodiment of the present application.

[0059] Please also see Figure 2 and Figure 3 In an optional embodiment of the present application, the input amplifier circuit 100 at least includes: an electrostatic protection circuit 120, a second capacitor module 130 and a first electronic switch module 140, wherein:

[0060] The input end of the electrostatic protection circuit 120 is used to receive the radio frequency signal to be amplified, and the electrostatic protection circuit 120 is grounded. Figure 3, which is composed of two reverse-connected grounding diodes in parallel, prevents electronic components or devices from being damaged by the electrostatic field, thereby improving the working stability and safety of the overall circuit.

[0061] The first end of the second capacitor module 130 is electrically connected to the output end of the electrostatic protection circuit 120, and the second end of the capacitor module is grounded; the second capacitor module 130 can be Figure 3 In the embodiment, the second electronic switch module M3 is composed of two capacitors connected in a T-shape, the drain of the second electronic switch module M3 is connected between the connection points of the two capacitors, wherein the first capacitor is connected in series between the electrostatic protection circuit 120 and the first electronic switch, and the second capacitor is connected to one end of the first capacitor and grounded. The second capacitor module 130 is used to stabilize and protect the subsequent devices and circuits of the amplified signal RFin together with the electrostatic protection circuit 120.

[0062] The control end of the first electronic switch module 140 is electrically connected to the second capacitor module 130 and the bias voltage, the source end of the first electronic switch module 140 is electrically connected to the amplification output circuit 200, and the drain end of the first electronic switch module 140 is electrically connected to the primary coil L1 in the tail inductor structure. The first electronic switch module 140 is an LNA main body amplification electronic switch, the signal is input from the gate of the second electronic switch device M2, and output from the drain of the first electronic switch device M1. The first electronic switch device M1 in the first electronic switch module 140 is a non-essential device.

[0063] Please continue to see Figure 2 and Figure 3 In an optional embodiment of the present application, the first electronic switch module 140 at least includes: a first electronic switch device M1 and a second electronic switch device M2, wherein:

[0064] The gate of the first electronic switch device M1 is electrically connected to the second capacitor module 130 and the first bias voltage Vb1, and the drain of the first electronic switch device M1 is electrically connected to the primary coil L1 in the tail inductor structure; the gate of the second electronic switch device M2 is used to connect the second bias voltage Vb2, the source of the second electronic switch is electrically connected to the amplification output circuit 200, and the drain of the second electronic switch device M2 is electrically connected to the source of the first electronic switch device M1. The first electronic switch device M1 and the second electronic switch device M2 constitute the amplification main circuit of the low-noise amplifier circuit 10, and perform a first-stage amplification on the signal to be amplified RFin. The first electronic switch device M1 and the second electronic switch device M2 can both be N-type electronic switches, which is currently only an example. The first electronic switch device M1 and the second electronic switch device M2 can also be P-type electronic switches, which only need to realize the above functions. The embodiment of the present application does not specifically limit the types of the first electronic switch device M1 and the second electronic switch device M2.

[0065] Please continue to see Figure 2 and Figure 3 In an optional embodiment of the present application, the amplifying output circuit 200 at least includes: a second electronic switch module M3, a second resonant circuit 220 and an output matching circuit 230, wherein:

[0066] Please also see Figure 3 and Figure 4 The gate of the second electronic switch module M3 is used to receive the enable signal Att_en, which is used to control the on and off of the second electronic switch. The drain of the second electronic switch module M3 is electrically connected to the second capacitor module 130. The second electronic switch module M3 can be composed of one or more electronic switches connected in series. The second electronic switch module M3 can be an N-type electronic switch. The second electronic switch module M3 and the second resonant circuit 220 and the output matching circuit 230 jointly realize the function of amplifying and outputting the signal.

[0067] Please also see Figure 2 and Figure 3 , the input end of the second resonant circuit 220 is electrically connected to the source of the second crystal module, and the second resonant circuit 220 is used to provide load impedance, frequency selection characteristics, adjust the capacitance and inductance values ​​according to the working rate, and the adjustable resistor is used to adjust the gain. In an optional embodiment of the present application, the second resonant circuit 220 at least includes: a second adjustable resistor R2, an adjustable capacitor C2 and an inductor L2 connected in parallel with each other, and the two ends of the second adjustable resistor R2, the adjustable capacitor C2 and the inductor L2 are respectively used to receive control signals and connected to the connection points of the second electronic switch module M3 and the output matching circuit 230.

[0068] See also Figure 2 The input end of the output matching circuit 230 is electrically connected to the output end of the second resonant circuit 220, and the output matching circuit 230 is used to perform frequency matching and gain adjustment on the signal output by the second resonant circuit 220 and then output the target RF signal. Figure 3 In an optional embodiment of the present application, the output matching circuit 230 at least includes: at least two groups of parallel capacitor devices 231, a first attenuation device Att1 and an output module 233, wherein:

[0069] The first end of the capacitor device 231 is electrically connected to the output end of the second resonant circuit 220; wherein, the capacitor device 231 is used for output frequency matching and isolating the DC level at the same time. The capacitor device 231 can be a fixed capacitor or an adjustable capacitor, and the operating frequency band can be adjusted by adjusting the capacitance.

[0070] The input end of the first attenuation device Att1 is electrically connected to the second end of the capacitor device 231, and the first attenuation device Att1 and the capacitor device 231 perform frequency matching and gain adjustment on the signal output by the second resonant circuit 220 to the target RF signal;

[0071] The input end of the output module 233 is electrically connected to the output end of the first attenuation device Att1 , and the output module 233 is used to output the target radio frequency signal.

[0072] The amplifier output circuit 200 in the embodiment of the present application at least includes: a second electronic switch module M3, a second resonant circuit 220 and an output matching circuit 230. Through the cooperation of the second electronic switch module M3, the second resonant circuit 220 and the output matching circuit 230, a more stable and reliable target RF signal can be output, further improving the working stability and reliability of the low-noise amplifier circuit 10 in the embodiment of the present application.

[0073] Please continue to see Figure 3 In an optional embodiment of the present application, the low noise amplifier circuit 10 further includes: a second attenuation device Att2, wherein:

[0074] The input end of the second attenuation device Att2 is electrically connected to the source of the second electronic switch module M3, and the output end of the second attenuation device Att2 is electrically connected to the second resonant device. The second attenuation device Att2 has the same function as the first attenuation device Att1, and is used to perform negative feedback at certain gain levels to achieve different gain levels to meet different gain requirements, and to reduce the nonlinear influence of the overall circuit, improve the linearity of the circuit, and thereby improve the working stability and reliability of the low-noise amplifier circuit 10, while also achieving input impedance matching.

[0075] Please continue to see Figure 3 In an optional embodiment of the present application, the amplifier input circuit 100 and the amplifier output circuit 200 are both multiple groups, corresponding to different RF signals, so as to meet different amplification requirements, thereby improving the application scope and working efficiency of the low-noise amplifier circuit 10 provided in the embodiment of the present application.

[0076] See also Figure 4 In an optional embodiment of the present application, the tail inductor structure in the amplifier input circuit 100 at least includes: the primary coil L1 and a plurality of third electronic switch modules M4, wherein:

[0077] The gate of the third electronic switch module M4 is used to receive a control signal, and the source of the third electronic switch module M4 is electrically connected to the primary coil L1 respectively. The third electronic switch is a switch tube, which realizes the switching function of the primary inductor. At the same time, the switch tube can also improve the ESD protection capability of the input tube M2.

[0078] The traditional winding method of the primary coil has no secondary coil. If the secondary coil is to be laid out on the layout, the layout area needs to be increased, resulting in an oversized device. In an optional embodiment of the present application, since the Q value requirement of the secondary coil L3 is not high, the secondary coil L3 can be arranged under the primary inductor L2 by winding, without increasing the additional area, thereby improving the surface area utilization of the device.

[0079] See also Figure 5 , which is a comparison diagram of the simulation results of the low-frequency amplifier circuit 10 provided in the embodiment of the present application and the traditional low-frequency amplifier circuit. The inductance value of the traditional inductor is relatively consistent in the entire frequency band, and the Q value gradually increases with the increase of frequency, and decreases after a certain frequency. In the low-noise amplifier using the traditional inductor, since the inductance characteristic is very strong at high frequencies and the Q value is also very high, the low-noise amplifier has poor stability at high frequencies and is prone to self-oscillation. The inductance and Q value of the inductor structure of the present application in the working frequency band are similar to those of the traditional inductor, but at a higher frequency than the working frequency band, the inductance decreases rapidly to close to 0, and the Q value also decreases rapidly. The inductance characteristic is very weak at high frequencies, which realizes the normal operation of the low-noise amplifier in the working frequency band, and the low-noise amplifier has the characteristics of high stability at a higher frequency than the working frequency band.

[0080] When the low-noise amplifier circuit is working, in order to prevent external static electricity from interfering with the signal in the low-noise amplifier circuit, in an optional embodiment of the present application, the low-noise amplifier circuit further includes: a multi-stage impedance protection module, at least one detection control module is arranged between two adjacent stages of the impedance protection modules, the input end of the front-stage impedance protection module in the multi-stage impedance protection module is electrically connected to the static power source, and the last-stage impedance protection module in the multi-stage impedance protection module is electrically connected to the static power source and the amplifier input circuit or the amplifier output circuit respectively;

[0081] The detection control module is used to detect the output voltage of the front-stage impedance protection module. The rear-stage impedance protection module is activated when the output voltage is greater than a preset voltage, and discharges the electrostatic voltage of the electrostatic power source; wherein the front-stage impedance protection module refers to an impedance protection module electrically connected to the detection control module and located at the front stage of the detection control module, and the rear-stage impedance protection module refers to an impedance protection module electrically connected to the detection control module and located at the rear stage of the detection control module. wherein the front-stage impedance protection module includes: a plurality of diode devices connected in series.

[0082] In an optional embodiment of the present application, the front-stage impedance protection module includes: a first diode module and a second diode module connected in parallel, the input ends of the first diode module and the second diode module are respectively electrically connected to the static power source, and the output ends of the first diode module and the second diode module are respectively grounded; wherein, the first diode module and the second diode module respectively include at least two diode devices connected in series, and the diode devices in the first diode module are connected in opposite directions to the diode devices in the second diode module.

[0083] In an optional embodiment of the present application, the post-stage impedance protection module at least includes: a transistor device, a control end of the transistor device is electrically connected to the detection control module, a first connection end of the transistor device is electrically connected to a connection point between the pre-stage impedance protection module and the electrostatic power source, a second connection end of the transistor device is grounded, and the transistor device is started when the operating voltage of the pre-stage impedance protection module is greater than a preset voltage, and discharges the electrostatic voltage of the electrostatic power source.

[0084] In an optional embodiment of the present application, the transistor device is an N-type transistor.

[0085] In an optional embodiment of the present application, the detection control module at least includes:

[0086] A first resistor device, wherein a first end of the first resistor device is electrically connected to the front-stage impedance protection module;

[0087] A second resistor device, wherein a first end of the second resistor device is electrically connected to a second end of the first resistor device and a control end of the post-stage impedance protection module respectively, and a second end of the second resistor device is grounded.

[0088] In an optional embodiment of the present application, it also includes: a current limiting device, wherein the input end of the current limiting device is electrically connected to the connection point between the front-stage impedance protection module and the static power source, and the output end of the current limiting device is electrically connected to the first connection end of the rear-stage impedance protection module.

[0089] In an optional embodiment of the present application, the current limiting device includes a plurality of capacitor devices connected in series.

[0090] In an optional embodiment of the present application, the multi-stage impedance protection module is a two-stage impedance protection module.

[0091] In an optional embodiment of the present application, the power supply of the low-noise amplifier circuit may be a dual power supply system, for example, including an analog power supply and a digital power supply. In an optional embodiment of the present application, optionally, a power supply power-on detection is provided for the low-noise amplifier circuit, and the low-noise amplifier circuit further includes:

[0092] a level shift unit, wherein an input end of the level shift unit is electrically connected to the digital power supply, and the level shift unit is used to pull up the digital power supply to a comparison voltage within a preset voltage range;

[0093] A level comparison output unit, wherein the input end of the level comparison output unit is electrically connected to the input end of the analog power supply and the level shift unit respectively, and the level comparison output unit is used to output a first control signal when the comparison voltage is greater than the analog voltage of the analog power supply, and output a second control signal when the comparison voltage is not greater than the analog voltage; wherein the first control signal controls the analog circuit not to work, and the second control signal controls the analog circuit to work.

[0094] In an optional embodiment of the present application, the level shift unit at least includes: a level shift module, an output end of the level shift module is electrically connected to an input end of the level comparison output unit;

[0095] A first transistor device, wherein a gate of the first transistor device is electrically connected to the digital power supply, a source of the first transistor device is electrically connected to an input end of the level shift module, and a drain of the first transistor is grounded.

[0096] In an optional embodiment of the present application, the level comparison output unit includes:

[0097] A level comparison module, wherein an input end of the level comparison module is electrically connected to an output end of the analog power supply and the level shift module respectively;

[0098] A comparison output module, wherein the control end of the comparison output module is electrically connected to the gate of the first transistor device, the input end of the comparison output module is electrically connected to the output end of the level comparison module, the first output end of the comparison output module is grounded, and the second output end of the comparison output module is used to output the first control signal or the second control signal.

[0099] In an optional embodiment of the present application, the level comparison module at least includes:

[0100] a second transistor device, wherein a gate and a drain of the second transistor device are electrically connected to an input terminal of the level shift module, and a source of the second transistor device is electrically connected to the analog power supply;

[0101] A third transistor device, wherein a gate of the third transistor device is electrically connected to the gate of the second transistor device, a source of the third transistor device is electrically connected to the analog power supply, and a drain of the third transistor device is electrically connected to the input end of the comparison output module.

[0102] In an optional embodiment of the present application, the comparison output module at least includes:

[0103] a fourth transistor device, wherein a gate of the fourth transistor device is electrically connected to the digital power supply, and a source of the fourth transistor device is electrically connected to a drain of the third transistor device;

[0104] A fifth transistor device, wherein a gate of the fifth transistor device is electrically connected to the digital power supply, a source of the fifth transistor device is electrically connected to a drain of the fourth transistor device, and a drain of the fifth transistor device is grounded.

[0105] In an optional embodiment of the present application, the first transistor device, the second transistor device, the third transistor device and the fourth transistor device are all transistor devices of the first conductivity type; the fifth transistor device is a transistor device of the second conductivity type; wherein the first conductivity type and the second conductivity type are different.

[0106] In an optional embodiment of the present application, the first transistor device, the second transistor device, the third transistor device and the fourth transistor device are all P-type transistor devices; and the fifth transistor device is an N-type transistor device.

[0107] In an optional embodiment of the present application, the level shift module includes a plurality of transistors, and each transistor is formed by connecting a different number of diodes.

[0108] In an optional embodiment of the present application, the number of the transistors is positively correlated with the absolute value of the voltage difference between the digital power supply and the analog power supply.

[0109] An embodiment of the present application provides a radio frequency system, comprising at least:

[0110] A low noise amplifier circuit 10 as described in any one of the above items.

[0111] The beneficial effects of the low-noise amplifier circuit 10 have been described in detail in the above embodiments and will not be repeated here.

[0112] Based on the above-mentioned low-noise amplifier circuit 10, the embodiment of the present application provides a radio frequency system that can weaken high-frequency parasitic oscillation phenomena and has higher working stability and reliability.

[0113] It should be understood that, although the various steps in the flow chart are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear description in this article, the execution of these steps is not strictly limited in order, and these steps can be executed in other orders. Moreover, at least a portion of the steps in the figure may include multiple sub-steps or multiple stages, and these sub-steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these sub-steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a portion of the sub-steps or stages of other steps.

[0114] The technical features of the above-described embodiments may be arbitrarily combined. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0115] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be construed as limiting the scope of the patent application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent application shall be subject to the attached claims.

Claims

1. A low noise amplifier circuit, characterized in that: At least: An amplifying input circuit and an amplifying output circuit; wherein the amplifying input circuit and the amplifying output circuit have at least one set of tail inductance structures; A first resonant circuit, wherein the first resonant circuit is a closed structure, the first resonant circuit is coupled to the tail inductance structure, and the first resonant circuit is used to discharge the current generated by the tail inductance structure; the first resonant circuit at least includes: A secondary coil is coupled to the primary coil in the tail inductor structure; A first capacitor module, wherein a first end of the first capacitor module is electrically connected to the secondary coil.

2. The low noise amplifier circuit according to claim 1, characterized in that: The first resonant circuit further includes: A first adjustable resistor, wherein a first end of the first adjustable resistor is electrically connected to a first end of the secondary coil, and a second end of the first adjustable resistor is electrically connected to a second end of the first capacitor module; wherein the secondary coil, the first capacitor module and the first adjustable resistor are electrically connected to each other to form a closed structure.

3. The low noise amplifier circuit according to claim 1, characterized in that: The amplifying input circuit at least comprises: An electrostatic protection circuit, wherein an input end of the electrostatic protection circuit is used to receive a radio frequency signal to be amplified, and the electrostatic protection circuit is grounded; A second capacitor module, wherein a first end of the second capacitor module is electrically connected to the output end of the electrostatic protection circuit, and a second end of the capacitor module is grounded; A first electronic switch module, wherein a control end of the first electronic switch module is electrically connected to the second capacitor module and a bias voltage, a source end of the first electronic switch module is electrically connected to the amplifying output circuit, and a drain end of the first electronic switch module is electrically connected to the primary coil in the tail inductor structure.

4. The low noise amplifier circuit according to claim 3, characterized in that: The first electronic switch module at least comprises: A first electronic switch device, wherein a gate of the first electronic switch device is electrically connected to the second capacitor module and a first bias voltage, and a drain of the first electronic switch device is electrically connected to the primary coil in the tail inductor structure; A second electronic switch device, wherein the gate of the second electronic switch device is used to connect to a second bias voltage, the source of the second electronic switch device is electrically connected to the amplifying output circuit, and the drain of the second electronic switch device is electrically connected to the source of the first electronic switch device.

5. The low noise amplifier circuit according to claim 3, characterized in that: The amplifying output circuit at least comprises: A second electronic switch module, wherein a gate of the second electronic switch module is used to receive an enable signal, and a drain of the second electronic switch module is electrically connected to the second capacitor module; a second resonant circuit, wherein an input end of the second resonant circuit is electrically connected to a source of the second crystal module; An output matching circuit, wherein the input end of the output matching circuit is electrically connected to the output end of the second resonant circuit, and the output matching circuit is used to perform frequency matching and gain adjustment on the signal output by the second resonant circuit and then output a target radio frequency signal.

6. The low noise amplifier circuit according to claim 5, characterized in that: The output matching circuit at least comprises: at least two groups of capacitors connected in parallel, wherein a first end of the capacitor is electrically connected to an output end of the second resonant circuit; a first attenuation device, wherein an input end of the first attenuation device is electrically connected to the second end of the capacitor device, and the first attenuation device and the capacitor device perform frequency matching and gain adjustment on a signal output by the second resonant circuit to the target radio frequency signal; An output module, wherein an input end of the output module is electrically connected to an output end of the first attenuation device, and the output module is used to output the target radio frequency signal.

7. The low noise amplifier circuit according to claim 5, characterized in that: The second resonant circuit at least includes: a second adjustable resistor, an adjustable capacitor and an inductor connected in parallel with each other.

8. The low noise amplifier circuit according to claim 5, characterized in that: Also includes: A second attenuation device, wherein an input end of the second attenuation device is electrically connected to the source of the second electronic switch module, and an output end of the second attenuation device is electrically connected to the second resonant device.

9. The low noise amplifier circuit according to claim 1, characterized in that: The amplifying input circuit and the amplifying output circuit are both in multiple groups, corresponding to different radio frequency signals respectively.

10. The low noise amplifier circuit according to claim 1, characterized in that: The tail inductor structure in the amplifying input circuit at least includes: The primary coil; A plurality of third electronic switch modules, wherein the gates of the third electronic switch modules are used to receive control signals, the sources of the third electronic switch modules are electrically connected to the primary coils respectively, and the drains of the third electronic switches are grounded.

11. A radio frequency system, characterized in that: At least: A low noise amplifier circuit as described in any one of claims 1 to 10 above.

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