A self-biased wideband low noise amplifier with current reuse structure

Abstract

The application discloses a self-bias wideband low-noise amplifier of a current multiplexing structure and relates to the field of radio frequency microelectronics technology.The self-bias wideband low-noise amplifier comprises a first-stage signal amplification unit and a second-stage signal amplification unit, wherein each signal amplification unit comprises an NMOS transistor and a PMOS transistor.The NMOS transistor and the PMOS transistor in the same signal amplification unit share the same current, and the signal is amplified through the NMOS transistor and the PMOS transistor simultaneously, current multiplexing is realized, the potentials of the gates and the drains of the transistors are the same, bias voltage is obtained through self-bias, and no additional bias circuit is needed.The biasing of the design scheme is simple, power consumption is reduced through circuit multiplexing, the input matching circuit designed realizes wideband input matching, and the overall bandwidth of the amplifier is improved.

Description

Technical Field

[0001] This invention relates to the field of radio frequency microelectronics technology, and more specifically to a self-biased broadband low-noise amplifier with a current multiplexing structure. Background Technology

[0002] Today, modern wireless systems and standards are developing at an unprecedented pace, and global wireless communication technology is experiencing explosive growth. To meet the rapidly increasing communication demands, integrating more systems and functions to save costs and improve reliability, higher-speed and higher-bandwidth transceivers have become an inevitable solution.

[0003] Against this backdrop, the design concept of low-noise amplifiers, as the core module of the RF receiver link, is evolving from the traditional narrowband single-band to a wideband structure. This means that higher requirements are placed on the bandwidth of low-noise amplifiers. At the same time, wideband amplifiers have a constraint relationship between bandwidth, gain and power consumption. They usually consume a large current, and the design often needs to minimize power consumption while ensuring bandwidth and gain.

[0004] Therefore, there is an urgent need to construct a broadband low-noise amplifier that achieves a flat gain curve and consumes relatively low power. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a self-biased broadband low-noise amplifier with a current multiplexing structure.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] A self-biased broadband low-noise amplifier with a current multiplexing structure includes a first-stage signal amplification unit and a second-stage signal amplification unit.

[0008] The input terminal of the first-stage signal amplification unit constitutes the input terminal of a self-biased broadband low-noise amplifier, and the input terminal of the second-stage signal amplification unit is connected to the output terminal of the first-stage signal amplification unit; the output terminal of the second-stage signal amplification unit constitutes the output terminal of the self-biased broadband low-noise amplifier.

[0009] The first-stage amplification unit is used to receive radio frequency signals and apply broadband impedance matching and first-stage amplification to the radio frequency signals in sequence to form a first-stage amplified signal; the second-stage amplification unit is used to apply second-stage amplification and impedance matching to the first-stage amplified signal in sequence to output a radio frequency amplified signal.

[0010] Furthermore, the first-stage signal amplification unit includes an input matching unit and a first signal amplification unit;

[0011] The input terminal of the input matching unit serves as the input terminal of the first-stage signal amplification unit, and the input terminal of the first-stage signal amplification unit is connected to the output terminal of the input matching unit; the output terminal of the first-stage signal amplification unit serves as the output terminal of the first-stage signal amplification unit; the input matching unit receives the radio frequency signal and performs broadband impedance matching on the radio frequency signal to form an input matching signal; the first signal amplification unit amplifies the input matching signal by one stage to form a first-stage amplified signal.

[0012] Furthermore, the input matching unit includes a coupling capacitor C. in First capacitor C1, first inductor L1, second inductor L2, DC blocking capacitor C block ;

[0013] The coupling capacitor C in One end serves as the input terminal of the input matching unit; the coupling capacitor C in The other end is connected to one end of the first capacitor C1, one end of the first inductor L1, and one end of the second inductor L2, respectively; the other end of the first capacitor C1 is grounded; the other end of the first inductor L1 is connected to the DC blocking capacitor C block One end is connected; the DC blocking capacitor C block The other end of the first inductor is grounded; the other end of the second inductor L2 serves as the output of the input matching unit.

[0014] Furthermore, the first signal amplification unit includes a first NMOS transistor M. n1 The first PMOS transistor M p1 First resistor R1, second resistor R2, third inductor L3, first source degenerate inductor L s1 ;

[0015] The first NMOS transistor M n1 The gate of the first PMOS transistor M p1 The gate of the first PMOS transistor and one end of the first resistor R1 together constitute the input terminal of the first-stage signal amplification unit; the other end of the first resistor R1 is connected to one end of the third inductor L3; the other end of the third inductor L3 is connected to one end of the second resistor R2; the first PMOS transistor M p1 The source of the first NMOS transistor is connected to the power supply; n1 The source and the first source degraded inductor L s1 One end is connected; the first source degraded inductor L s1 The other end is grounded; the other end of the second resistor R2, and the first NMOS transistor M n1 The drain of the first PMOS transistor M p1 The drains together form the output terminal of the first-stage signal amplification unit.

[0016] Furthermore, the second-stage signal amplification unit includes a second signal amplification unit and an output matching unit;

[0017] The input terminal of the second signal amplification unit serves as the input terminal of the second-stage signal amplification unit, and the input terminal of the output matching unit is connected to the output terminal of the second signal amplification unit; the output terminal of the output matching unit serves as the output terminal of the first-stage signal amplification unit; the second signal amplification unit amplifies the received first-stage amplified signal to form a second-stage amplified signal; the output matching unit performs impedance matching on the second-stage amplified signal and outputs a radio frequency amplified signal.

[0018] Furthermore, the second amplification unit includes a second NMOS transistor M. n2 The second PMOS transistor M p2 Resistor R3, resistor R4, inductor L4, inductor L5, and source degradation inductor L6 s2 ;

[0019] One end of the fourth inductor L4 serves as the input terminal of the second signal amplification unit; the other end of the fourth inductor L4 is connected to the second NMOS transistor M. n2 The gate of the second PMOS transistor M p2 The gate of the second PMOS transistor is connected to one end of the third resistor R3; the other end of the third resistor R3 is connected to one end of the fifth inductor L5; the other end of the fifth inductor L5 is connected to one end of the fourth resistor R4; the second PMOS transistor M p2 The source of the second NMOS transistor is connected to the power supply; n2 The source and the second source degraded inductance L s2 One end is connected; the second source degraded inductor L s2 The other end is grounded; the second NMOS transistor M n2 The drain of the second PMOS transistor M p2 The drain of the first resistor and the other end of the fourth resistor R4 together form the output terminal of the second amplifier unit.

[0020] Furthermore, the output matching unit includes a sixth inductor L6, a second capacitor C2, and an output coupling capacitor C. out ;

[0021] One end of the sixth inductor L6 serves as the input terminal of the output matching unit; the other end of the sixth inductor L6 is connected to one end of the second capacitor C2 and the output coupling capacitor C1, respectively. out One end of the capacitor is connected; the other end of the second capacitor C2 is grounded; the output coupling capacitor C out The other end serves as the output of the output matching unit.

[0022] The beneficial effects of adopting the above technical solution are as follows:

[0023] (1) The present invention uses a current multiplexing structure to stack NMOS transistors and PMOS transistors in series, so that they share the same DC current and participate in signal amplification at the same time, thereby greatly reducing the total power consumption under the condition of obtaining the same gain.

[0024] (2) The present invention adopts a self-biased structure, which directly connects the gate and drain of the transistor through a resistor and an inductor, so that the DC potential of the gate and drain are the same, automatically establishing the operating point required for amplification, without the need for additional bias circuit design, thereby saving chip area and reducing design complexity and cost.

[0025] (3) The present invention effectively separates the parasitic capacitance of the transistor by integrating the design of the input matching network, the parallel negative feedback of the resistor, the interstage matching inductor and the output L-type matching network, and expands the operating frequency range of the amplifier, so that the amplifier can maintain a flat gain curve and good impedance matching in a wider frequency band. Attached Figure Description

[0026] Figure 1 This is a system block diagram of the self-biased broadband low-noise amplifier with the current multiplexing structure designed in this invention.

[0027] Figure 2 A circuit diagram of the self-biased broadband low-noise amplifier circuit with the current multiplexing structure designed in this invention.

[0028] Figure 3 This is a circuit diagram of a current-reused broadband low-noise amplifier circuit with an externally biased structure. Detailed Implementation

[0029] The technical solution of the present invention will be described in detail below with reference to the accompanying drawings.

[0030] refer to Figure 1 A self-biased broadband low-noise amplifier with a current multiplexing structure includes a first-stage signal amplification unit and a second-stage signal amplification unit.

[0031] The input terminal of the first-stage signal amplification unit constitutes the input terminal of a self-biased broadband low-noise amplifier, and the input terminal of the second-stage signal amplification unit is connected to the output terminal of the first-stage signal amplification unit; the output terminal of the second-stage signal amplification unit constitutes the output terminal of the self-biased broadband low-noise amplifier.

[0032] The first-stage amplification unit is used to receive radio frequency signals and apply broadband impedance matching and first-stage amplification to the radio frequency signals in sequence to form a first-stage amplified signal; the second-stage amplification unit is used to apply second-stage amplification and impedance matching to the first-stage amplified signal in sequence to output a radio frequency amplified signal.

[0033] Furthermore, the first-stage signal amplification unit includes an input matching unit and a first signal amplification unit;

[0034] The input terminal of the input matching unit serves as the input terminal of the first-stage signal amplification unit, and the input terminal of the first-stage signal amplification unit is connected to the output terminal of the input matching unit; the output terminal of the first-stage signal amplification unit serves as the output terminal of the first-stage signal amplification unit; the input matching unit receives the radio frequency signal and performs broadband impedance matching on the radio frequency signal to form an input matching signal; the first signal amplification unit amplifies the input matching signal by one stage to form a first-stage amplified signal.

[0035] refer to Figure 2 The input matching unit includes a coupling capacitor C. in First capacitor C1, first inductor L1, second inductor L2, DC blocking capacitor C block ;

[0036] The coupling capacitor C in One end serves as the input terminal of the input matching unit; the coupling capacitor C in The other end is connected to one end of the first capacitor C1, one end of the first inductor L1, and one end of the second inductor L2, respectively; the other end of the first capacitor C1 is grounded; the other end of the first inductor L1 is connected to the DC blocking capacitor C block One end is connected; the DC blocking capacitor C block The other end of the first inductor is grounded; the other end of the second inductor L2 serves as the output of the input matching unit.

[0037] Specifically, the coupling capacitor C in and DC blocking capacitor C block It has the function of isolating DC; capacitor C1, inductor L1, and inductor L2 together form the input matching network, which provides bias for the first signal amplification unit.

[0038] refer to Figure 2 The first signal amplification unit includes a first NMOS transistor M. n1 The first PMOS transistor M p1 First resistor R1, second resistor R2, third inductor L3, first source degenerate inductor L s1 ;

[0039] The first NMOS transistor M n1 The gate of the first PMOS transistor M p1The gate of the first PMOS transistor and one end of the first resistor R1 together constitute the input terminal of the first-stage signal amplification unit; the other end of the first resistor R1 is connected to one end of the third inductor L3; the other end of the third inductor L3 is connected to one end of the second resistor R2; the first PMOS transistor M p1 The source of the first NMOS transistor is connected to the power supply; n1 The source and the first source degraded inductor L s1 One end is connected; the first source degraded inductor L s1 The other end is grounded; the other end of the second resistor R2, and the first NMOS transistor M n1 The drain of the first PMOS transistor M p1 The drains together form the output terminal of the first-stage signal amplification unit.

[0040] Specifically, the third inductor L3 is used to block radio frequency signals; the first resistor R1 and the second resistor R2 serve as resistive negative feedback, providing impedance matching; the first source degradation inductor L... s1 Used to achieve impedance matching in the preceding stage.

[0041] Furthermore, the second-stage signal amplification unit includes a second signal amplification unit and an output matching unit;

[0042] The input terminal of the second signal amplification unit serves as the input terminal of the second-stage signal amplification unit, and the input terminal of the output matching unit is connected to the output terminal of the second signal amplification unit; the output terminal of the output matching unit serves as the output terminal of the first-stage signal amplification unit; the second signal amplification unit amplifies the received first-stage amplified signal to form a second-stage amplified signal; the output matching unit performs impedance matching on the second-stage amplified signal and outputs a radio frequency amplified signal.

[0043] refer to Figure 2 The second amplification unit includes a second NMOS transistor M. n2 The second PMOS transistor M p2 Resistor R3, resistor R4, inductor L4, inductor L5, and source degradation inductor L6 s2 ;

[0044] One end of the fourth inductor L4 serves as the input terminal of the second signal amplification unit; the other end of the fourth inductor L4 is connected to the second NMOS transistor M. n2 The gate of the second PMOS transistor M p2 The gate of the second PMOS transistor is connected to one end of the third resistor R3; the other end of the third resistor R3 is connected to one end of the fifth inductor L5; the other end of the fifth inductor L5 is connected to one end of the fourth resistor R4; the second PMOS transistor M p2The source of the second NMOS transistor is connected to the power supply; n2 The source and the second source degraded inductance L s2 One end is connected; the second source degraded inductor L s2 The other end is grounded; the second NMOS transistor M n2 The drain of the second PMOS transistor M p2 The drain of the first resistor and the other end of the fourth resistor R4 together form the output terminal of the second amplifier unit.

[0045] Specifically, the fourth inductor L4 is used to isolate the parasitic capacitance of each transistor in the first-stage signal amplification unit and the second-stage signal amplification unit, thereby expanding the bandwidth; the fifth inductor L5 is used to block radio frequency signals; the third resistor R3 and the fourth resistor R4 serve as resistive negative feedback, providing impedance matching; the second source degradation inductor L... s2 Used to achieve impedance matching in the preceding stage;

[0046] refer to Figure 2 The output matching unit includes a sixth inductor L6, a second capacitor C2, and an output coupling capacitor C. out ;

[0047] One end of the sixth inductor L6 serves as the input terminal of the output matching unit; the other end of the sixth inductor L6 is connected to one end of the second capacitor C2 and the output coupling capacitor C1, respectively. out One end of the capacitor is connected; the other end of the second capacitor C2 is grounded; the output coupling capacitor C out The other end serves as the output of the output matching unit.

[0048] Specifically, the sixth inductor L6 and the second capacitor C2 form an L-type matching network to provide output impedance matching.

[0049] In this embodiment, the gate and drain potentials of each transistor are the same, and the bias voltage is obtained through self-biasing, without the need for an additional bias circuit; and the NMOS transistors and PMOS transistors in the same signal amplification unit share the same current, and the signal is amplified by both NMOS transistors and PMOS transistors at the same time, realizing current multiplexing.

[0050] refer to Figure 3When an amplifier lacks a self-biasing structure, an additional bias network is needed to provide gate bias to each amplifying transistor. The gain performance of a current-multiplexed amplifier circuit is highly sensitive to the bias voltage, requiring it to be strictly set at half the supply voltage. When the bias voltage deviates from the ideal potential, the bias states of the NMOS and PMOS transistors deviate, significantly degrading the gain performance. Furthermore, the parasitic parameters of the DC blocking capacitor introduced by the external bias structure will affect the input impedance, interstage impedance, and gain flatness. Therefore, this embodiment effectively reduces the disturbance to broadband impedance matching and the impact on circuit gain caused by external bias by forming a bias voltage within the amplification unit.

[0051] The above description is merely a preferred embodiment of the present invention and does not constitute any limitation on the present invention. Any simple modifications, alterations, or equivalent structural changes made to the above embodiments based on the technical essence of the present invention shall still fall within the protection scope of the present invention.

Claims

1. A self-biased broadband low-noise amplifier with a current multiplexing structure, characterized in that, Includes a first-stage signal amplification unit and a second-stage signal amplification unit; The input terminal of the first-stage signal amplification unit constitutes the input terminal of a self-biased broadband low-noise amplifier, and the input terminal of the second-stage signal amplification unit is connected to the output terminal of the first-stage signal amplification unit; the output terminal of the second-stage signal amplification unit constitutes the output terminal of the self-biased broadband low-noise amplifier. The first-stage amplification unit is used to receive radio frequency signals and apply broadband impedance matching and first-stage amplification to the radio frequency signals in sequence to form a first-stage amplified signal; the second-stage amplification unit is used to apply second-stage amplification and impedance matching to the first-stage amplified signal in sequence to output a radio frequency amplified signal.

2. The self-biased broadband low-noise amplifier with a current multiplexing structure according to claim 1, characterized in that, The first-stage signal amplification unit includes an input matching unit and a first signal amplification unit; The input terminal of the input matching unit serves as the input terminal of the first-stage signal amplification unit, and the input terminal of the first-stage signal amplification unit is connected to the output terminal of the input matching unit; the output terminal of the first-stage signal amplification unit serves as the output terminal of the first-stage signal amplification unit; the input matching unit receives the radio frequency signal and performs broadband impedance matching on the radio frequency signal to form an input matching signal; the first signal amplification unit amplifies the input matching signal by one stage to form a first-stage amplified signal.

3. The self-biased broadband low-noise amplifier with a current multiplexing structure according to claim 2, characterized in that, The input matching unit includes a coupling capacitor C. in First capacitor C1, first inductor L1, second inductor L2, DC blocking capacitor C block ; The coupling capacitor C in One end serves as the input terminal of the input matching unit; the coupling capacitor C in The other end is connected to one end of the first capacitor C1, one end of the first inductor L1, and one end of the second inductor L2, respectively; the other end of the first capacitor C1 is grounded; the other end of the first inductor L1 is connected to the DC blocking capacitor C block One end is connected; the DC blocking capacitor C block The other end of the first inductor is grounded; the other end of the second inductor L2 serves as the output of the input matching unit.

4. The self-biased broadband low-noise amplifier with a current multiplexing structure according to claim 2, characterized in that, The first signal amplification unit includes a first NMOS transistor M n1 The first PMOS transistor M p1 First resistor R1, second resistor R2, third inductor L3, first source degenerate inductor L s1 ; The first NMOS transistor M n1 The gate of the first PMOS transistor M p1 The gate of the first PMOS transistor and one end of the first resistor R1 together constitute the input terminal of the first-stage signal amplification unit; the other end of the first resistor R1 is connected to one end of the third inductor L3; the other end of the third inductor L3 is connected to one end of the second resistor R2; the first PMOS transistor M p1 The source of the first NMOS transistor is connected to the power supply; n1 The source and the first source degraded inductor L s1 One end is connected; the first source degraded inductor L s1 The other end is grounded; the other end of the second resistor R2, and the first NMOS transistor M n1 The drain of the first PMOS transistor M p1 The drains together form the output terminal of the first-stage signal amplification unit.

5. The self-biased broadband low-noise amplifier with a current multiplexing structure according to claim 1, characterized in that, The second-stage signal amplification unit includes a second signal amplification unit and an output matching unit; The input terminal of the second signal amplification unit serves as the input terminal of the second-stage signal amplification unit, and the input terminal of the output matching unit is connected to the output terminal of the second signal amplification unit; the output terminal of the output matching unit serves as the output terminal of the first-stage signal amplification unit. The received first-stage amplified signal is amplified by the second signal amplification unit to form a second-stage amplified signal; The output matching unit performs impedance matching on the secondary amplified signal and outputs the radio frequency amplified signal.

6. The self-biased broadband low-noise amplifier with a current multiplexing structure according to claim 5, characterized in that, The second amplification unit includes a second NMOS transistor M n2 The second PMOS transistor M p2 Resistor R3, resistor R4, inductor L4, inductor L5, and source degradation inductor L6 s2 ; One end of the fourth inductor L4 serves as the input terminal of the second signal amplification unit; the other end of the fourth inductor L4 is connected to the second NMOS transistor M. n2 The gate of the second PMOS transistor M p2 The gate of the second PMOS transistor is connected to one end of the third resistor R3; the other end of the third resistor R3 is connected to one end of the fifth inductor L5; the other end of the fifth inductor L5 is connected to one end of the fourth resistor R4; the second PMOS transistor M p2 The source of the second NMOS transistor is connected to the power supply; n2 The source and the second source degraded inductance L s2 One end is connected; the second source degraded inductor L s2 The other end is grounded; the second NMOS transistor M n2 The drain of the second PMOS transistor M p2 The drain of the first resistor and the other end of the fourth resistor R4 together form the output terminal of the second amplifier unit.

7. The self-biased broadband low-noise amplifier with a current multiplexing structure according to claim 5, characterized in that, The output matching unit includes a sixth inductor L6, a second capacitor C2, and an output coupling capacitor C. out ; One end of the sixth inductor L6 serves as the input terminal of the output matching unit; the other end of the sixth inductor L6 is connected to one end of the second capacitor C2 and the output coupling capacitor C1, respectively. out One end of the capacitor is connected; the other end of the second capacitor C2 is grounded; the output coupling capacitor C out The other end serves as the output of the output matching unit.

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