Liquid nitrogen temperature zone low-noise amplifier device

Abstract

The invention relates to a low-noise amplifier device in a liquid nitrogen temperature zone. The amplifier device includes a first stage die cell, a second stage die cell, an inter-stage matching circuit, and an output matching circuit. The first-stage tube core unit comprises an amplifier GaAS pHEMT tube core T1, S parameters of a gold wire L1 and a gold wire L2, an input blocking capacitor C1, a T1 gate bias circuit, a T1 drain bias circuit and an RLC feedback circuit. The second-stage tube core unit comprises a GaAs pHEMT tube core T2, S parameters of a gold wire L3 and a gold wire L4, a T2 gate bias circuit, a T2 drain bias circuit and an RLC feedback circuit. The low-temperature amplifier can work below a liquid nitrogen temperature zone, is low in noise temperature and high in gain flatness in a broadband range, and can be well used as a low-noise amplification circuit.

Description

Technical Field

[0001] This invention relates to a low-noise amplifier device in the liquid nitrogen temperature range, specifically to a low-noise amplifier device designed for 77K low-temperature environments, belonging to the fields of low-temperature electronics and microwave technology. Background Technology

[0002] Cryogenic microwave devices are currently developing towards wider operating frequency ranges and multi-unit integration, and their applications are becoming increasingly widespread. For example, in radio astronomy, cryogenic microwave devices are used in high-sensitivity superconducting mixers; in the front end of mobile phone base stations, they are used in superconducting filters and amplifiers; in addition, in fields such as deep space exploration satellite communications and particle detectors in fundamental physics experiments, cryogenic microwave devices are also widely used in key components such as preamplifiers. Summary of the Invention

[0003] Technical issues: Currently, widely used gallium arsenide-based MMIC devices cannot meet the noise temperature requirements at low temperatures, and the room temperature S-parameters of common dies often cannot meet the requirements of low-noise amplifier designs at low temperatures.

[0004] Therefore, it is necessary to design a low-noise amplifier that can operate at low temperature (77K) based on the S-parameters of the die at low temperature to meet the application requirements of high gain level and low noise temperature.

[0005] In order to overcome the shortcomings of the prior art, the purpose of this invention is to provide a low-noise amplifier device in the liquid nitrogen temperature range.

[0006] Technical Solution: To solve the above-mentioned technical problems, the technical solution of the present invention is as follows: A low-noise amplifier device in the liquid nitrogen temperature range, the amplifier device includes a first-stage die unit, a second-stage die unit, an inter-stage matching circuit, and an output matching circuit. The first-stage die unit includes an amplifier GaAs pHEMT die T1, gold wires L1 and L2, an input DC blocking capacitor C1, a gate bias circuit for T1, a drain bias circuit for T1, and an RLC feedback circuit. The gate of die T1 is connected to the gate bias circuit of T1 through gold wire L1; the drain of die T1 is connected to the drain bias circuit of T1 through gold wire L2; one end of the RLC feedback circuit is connected to gold wire L1, and the other end is connected to gold wire L2. The input DC blocking capacitor C1 is connected to the common point of gold wire L1. The second-stage die unit includes a GaAs pHEMT die T2, gold wires L3 and L4, a gate bias circuit for T2, a drain bias circuit for T2, and an RLC feedback circuit. The gate of die T2 is connected to the gate bias circuit of T2 via gold wire L3; the drain of die T2 is connected to the drain bias circuit of T2 via gold wire L4; one end of the RLC feedback circuit is connected to gold wire L1 and the other end is connected to gold wire L2.

[0007] The S-parameters of the amplifier die were extracted using a TRL calibrator at liquid nitrogen temperature. The vector network analyzer was then calibrated at low temperature using the TRL calibrator, enabling the vector network analyzer to measure the S-parameters of die T1, gold wire L1, and gold wire L2, as well as the S-parameters of die T2, gold wire L3, and gold wire L4.

[0008] The first-stage die unit is bonded to the gate of GaAs pHEMT die T1 via gold wire L1, and gold wire L2 is bonded to GaAs... The drain of pHEMT die T1 has one end of the input DC blocking capacitor C1 connected to the RF input signal and the other end connected to the gold wire L1. The gate bias circuit of T1 consists of Lp1 and Cp1. One end of Lp1 is connected to the gold wire L1 and C1 through a microstrip line, and the other end is connected to Cp1 and the first stage power supply. The other end of Cp1 is grounded. The drain bias circuit of T1 consists of Lp2, Cp2 and Rp1. One end of Lp2 is connected to the gold wire L2 through a microstrip line, and the other end is connected to Cp2 and Rp1. The other end of Cp2 is grounded. The other end of Rp1 is connected to the second stage power supply. The RLC feedback circuit consists of Lf1, Rf1 and Cf1. One end of Lf1 is connected to the gold wire L1 and the other end is connected to Rf1. The other end of Rf1 is connected to Cf1. The other end of Cf1 is connected to Lp2.

[0009] The first-stage power supply is a DC power supply, used to provide voltage Vgs1 to the gate of the first-stage amplifier.

[0010] The second-stage power supply is a DC power supply, used to provide voltage Vds1 to the drain of the first-stage amplifier.

[0011] The second-stage die unit is bonded to the gate of the GaAs pHEMT die T2 via gold wire L3, and gold wire L4 is bonded to the drain of the GaAs pHEMT die T2. The gate bias circuit of T2 consists of Lp3 and Cp3. One end of Lp3 is connected to gold wires L3 and C3 via a microstrip line, and the other end is connected to Cp3 and the third-stage power supply. The other end of Cp3 is grounded. The drain bias circuit of T2 consists of Lp4, Cp4, and Rp2. One end of Lp4 is connected to gold wire L4 via a microstrip line, and the other end is connected to Cp4 and Rp2. The other end of Cp2 is grounded, and the other end of Rp2 is connected to the fourth-stage power supply. The RLC feedback circuit consists of Lf2, Rf2, and Cf2. One end of Lf2 is connected to gold wire L3, and the other end is connected to Rf2. The other end of Rf2 is connected to Cf2, and the other end of Cf2 is connected to Lp4.

[0012] The third-stage power supply is a DC power supply, used to provide the gate voltage Vgs2 of the second-stage amplifier.

[0013] The fourth stage power supply is a DC power supply, which provides voltage Vds2 to the drain of the second stage amplifier.

[0014] The interstage matching circuit includes C2, C3, and L1. One end of C2 is connected to the output of the first-stage amplifier, and the other end is connected to one end of L1 and C3. The other end of L1 is grounded. The other end of C3 is connected to the input of the second-stage amplifier.

[0015] The output matching circuit includes C4, C5, and L2. One end of C4 is connected to the output of the second-stage amplifier, and the other end is connected to one end of L2 and C4. The other end of L2 is grounded. The other end of C4 is connected to the RF output.

[0016] Resistors Rp1, Rp2, Rf1, and Rf2 are all thin-film resistors.

[0017] Filter capacitors Cp1, Cp2, Cp3, and Cp4, as well as input DC blocking capacitors C1, C2, C3, C4, and C5, are all surface-mount capacitors in 0402 packages.

[0018] The resistors Rp1, Rp2, Rf1, and Rf2 are all surface mount resistors in 0402 packages.

[0019] Both die T1 and die T2 are enhanced E-pHEMT.

[0020] The above circuit design method is used to design a low-noise amplifier device in the liquid nitrogen temperature range. It employs a dual-supply system, with DC blocking capacitors at the input and output terminals to prevent DC components from interfering with the RF signal. A high-frequency choke inductor is added to the bias network to ensure circuit stability. Compared to a single-supply system, the dual-supply system offers more flexible bias adjustment capabilities, making it suitable for high-performance circuits requiring precise control of the operating point. The introduction of an RLC feedback circuit effectively reduces input noise and improves the amplifier's input VSWR, resulting in a lower noise temperature in cryogenic environments. By precisely adjusting the parameters of the feedback network, the impedance matching at the input port can be optimized to maximize signal transmission efficiency and minimize reflection loss. The interstage matching circuit and output matching circuit adopt a T-type matching structure, enabling the network to provide good impedance matching over a wide frequency range, suitable for circuit designs at various frequencies, and also exhibiting good power transfer characteristics and low power loss. The advantage of this device lies in its "calibration-measurement-design" closed-loop solution, addressing industry pain points such as large measurement errors between design and actual implementation and degraded amplifier noise performance. This provides a highly reliable cryogenic microwave hardware platform for quantum computing receivers, deep space exploration receiving systems, and more. The technology employed is HMIC, a microwave circuit technology combining discrete components and integrated processes. Through precision micro-assembly, transistors, thin-film capacitors, thin-film resistors, and miniature inductors are bonded onto a semiconductor substrate to form a complete amplifier circuit system. The advantages of HMIC include ease of circuit adjustment and modification, shorter design and development cycles, shorter manufacturing time, rapid iteration, and low cost, making it the preferred solution in the early stages of amplifier development. Furthermore, compared to MMIC, HMIC offers a wider variety and greater flexibility in the available processes, reducing the risks associated with semiconductor process restrictions and allowing for the integration of transistors from different processes in circuit design. This balances R&D efficiency with cost control.

[0021] Beneficial effects

[0022] This invention provides a low-noise amplifier device for the liquid nitrogen temperature range, designed for low-noise amplifier devices operating at 77K. This invention utilizes HMIC's microwave circuit technology, which combines discrete components and integrated circuit processes, to design a complete low-noise amplifier device for the liquid nitrogen temperature range.

[0023] Furthermore, compared to MMIC, HMIC offers a wider variety of flexible process options, reducing the risks associated with semiconductor process restrictions and allowing for circuit design that combines transistors from different processes. This balances R&D efficiency with cost control. This invention considers the impact of temperature and employs circuit S-parameters based on low-temperature RF die bonding with gold wires to ensure the accuracy of the low-temperature LNA design. This avoids the complex process and inaccuracies associated with removing the gold wires, which could lead to significant performance discrepancies between the actual and simulated circuits. Attached Figure Description

[0024] Figure 1 This is the schematic diagram of the low-temperature, low-noise amplifier described in this invention.

[0025] Figure 2 This is a schematic diagram of the TRL calibration component described in this invention.

[0026] Figure 3 This is the die test diagram described in this invention.

[0027] Figure 4 This is a graph showing the low-temperature S-parameter test results of the chip power supply circuit and transistor described in this invention.

[0028] Figure 5 This is a graph showing the S-parameter test results of the low-temperature, low-noise amplifier described in this invention.

[0029] Figure 6 This is a graph showing the noise test results of the low-temperature, low-noise amplifier described in this invention.

[0030] Figure 7 This is a graph showing the stability test results of the low-temperature, low-noise amplifier described in this invention. Detailed Implementation

[0031] To make the content of this invention easier to understand, the invention will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0032] Example:

[0033] The noise figure of a cryogenic low-noise amplifier is a key indicator of the sensitivity of a receiving system, and its stability at low temperatures (liquid nitrogen range) and circuit reliability are crucial to the long-term stability of the system. Existing common RF transistors provide S-parameters measured at room temperature, which has significant limitations in the design technology of amplifiers in ultra-low temperature environments. To address these issues, this invention provides a liquid nitrogen temperature range low-noise amplifier device.

[0034] like Figure 1 The paper presents a low-noise amplifier device in the liquid nitrogen temperature range, which adopts a circuit topology with hybrid matching based on GaAs die, and provides a simulation method for suppressing low-frequency oscillations and improving high-frequency noise temperature.

[0035] This embodiment describes the design of a low-temperature, low-noise amplifier operating in the 2.5GHz-4GHz frequency band. Its specifications include a wide operating frequency bandwidth, high in-band noise temperature requirements, and significant challenges in gain flatness and VSWR matching. To address the low-noise issue, this embodiment utilizes a GaAs pHEMT die with an ultra-low noise temperature at low temperatures. The matching circuit is designed for minimum noise and optimal VSWR matching. The amplifier in this embodiment meets the low-temperature, low-noise requirements, achieving a minimum noise temperature of only 1dB in the 2.5GHz-4GHz range. Further noise levels can be achieved by adjusting the operating voltage and current at low temperatures. This results in a wideband, high-gain output for the 2.5GHz-4GHz low-temperature amplifier, while also balancing the gain non-flatness of the die and improving the overall flatness of the low-temperature, low-noise amplifier across its ultra-wide bandwidth.

[0036] like Figure 1 The diagram shows the schematic of a low-temperature, low-noise amplifier. The first-stage die T1 has a gate bias circuit and a drain bias circuit. The gate of the transistor is connected to the power supply Vgs1 through a choke inductor Lp1 and a bypass capacitor Cp1, while the source is connected to the power supply Vds1 through a choke inductor Lp2, a bypass capacitor Cp2, and Rp1. Figure 4The diagram shows the S-parameters of die T1, with the gate (G) and drain (D) terminals bonded to the PCB via gold wires L1 and L2 at low temperatures. The measured S-parameters, with Ids of 16mA, are as follows: When the power supply Vgs is 0.56V, Vds is 3V, and the S-parameters are [Ids], the die may be more difficult to turn on at low temperatures (for enhancement-mode devices), resulting in a smaller on-state current. At low temperatures, due to increased mobility and faster carrier velocity, the drain current is larger and the transconductance is higher for a given overdrive voltage. Device speed (ft, fmax) is significantly improved. The bias network is primarily responsible for providing a suitable quiescent operating point for each stage of the transistor, including gate and drain power supplies. A dual power supply is used, with DC blocking capacitors at the input and output to prevent DC components from interfering with the RF signal. A high-frequency choke inductor is added to the bias network to ensure circuit stability. Compared to a single power supply, a dual power supply offers more flexible bias adjustment capabilities, making it suitable for high-performance circuits requiring precise control of the operating point. The Lf1, Cf1, and Rf1 negative feedback architecture is the most widely used architecture. It can achieve good gain flatness within a certain bandwidth octave, while improving LNA stability and obtaining good VSWR. Rf1 plays the most critical role in the entire feedback loop; the amount of feedback it introduces determines the gain and bandwidth. Lf1's role is to adjust the frequency and ensure gain flatness within the bandwidth. Cf1's role is to isolate DC. The DC blocking capacitor C1 and the RLC feedback circuit together constitute minimum noise matching, improving the matching degree between the input port and the source (typically 50Ω). The smaller S11 (e.g., |S11| < −10 dB), the less reflection, and the more power enters the LNA. C2, C3, and L1 constitute an interstage matching circuit. By adjusting the values ​​of C2 and C3, the input / output impedance transformation ratio can be changed, and good matching can be achieved within a certain frequency band by combining it with the resonant frequency of L1. It is convenient for variable loads or fine-tuning. The second-stage die T2 has gate and drain bias circuits. The gate of the transistor is connected to the power supply Vgs2 via choke inductor Lp3 and bypass capacitor Cp3, while the source is connected to the power supply Vds2 via choke inductor Lp4, bypass capacitor Cp4, and Rp2. The Lf2, Cf2, and Rf2 negative feedback architecture primarily provides smoothness for gain adjustment. The output matching circuit consists of C4, C5, and L2. The T-type network provides good impedance matching over a wide frequency range, making it suitable for circuit designs at various frequencies. It also features good power transfer characteristics and low power loss.

[0037] This embodiment provides a low-temperature, low-noise amplifier designed based on a GaAs die at 77K, with an operating frequency range of 2.5GHz-4GHz. During testing, after calibrating the instrument, the amplifier was installed in a cryogenic Dewar. Once the device's operating temperature dropped below 77K, it was held at that temperature for one hour. The noise temperature of the device was then tested using a high-precision cryogenic amplifier noise testing platform. The measured curve is shown below. Figure 6 As shown, the gain, standing wave ratio (VSWR), and gain flatness of the device were tested using a vector network analyzer. The measured curves are shown below. Figure 5 As shown. From Figure 5 , Figure 6 As can be seen, the device has a noise temperature of less than 1dB, a gain of greater than 29dB, a gain flatness of ±0.5dB, and a standing wave ratio better than -10dB in the 2.5-4GHz frequency range.

[0038] The above-described embodiments are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A low-noise amplifier device in the liquid nitrogen temperature range, characterized in that, The amplifier device includes a first-stage die unit, a second-stage die unit, an inter-stage matching circuit, and an output matching circuit. The first-stage die unit includes an amplifier GaAs pHEMT die T1, gold wires L1 and L2, an input DC blocking capacitor C1, a gate bias circuit for T1, a drain bias circuit for T1, and an RLC feedback circuit. The gate of die T1 is connected to the gate bias circuit of T1 through gold wire L1; the drain of die T1 is connected to the drain bias circuit of T1 through gold wire L2; one end of the RLC feedback circuit is connected to gold wire L1, and the other end is connected to gold wire L2; the input DC blocking capacitor C1 is connected to the common point of gold wire L1. The second-stage die unit includes a GaAs pHEMT die T2, gold wires L3 and L4, a gate bias circuit for T2, a drain bias circuit for T2, and an RLC feedback circuit. The gate of die T2 is connected to the gate bias circuit of T2 via gold wire L3; the drain of die T2 is connected to the drain bias circuit of T2 via gold wire L4; one end of the RLC feedback circuit is connected to gold wire L1 and the other end is connected to gold wire L2.

2. The low-noise amplifier device in the liquid nitrogen temperature range according to claim 1, characterized in that, The S-parameters of the amplifier die were extracted using a TRL calibrator at liquid nitrogen temperature. The vector network analyzer was then calibrated at low temperature using the TRL calibrator, enabling the vector network analyzer to measure the S-parameters of die T1, gold wire L1, and gold wire L2, as well as the S-parameters of die T2, gold wire L3, and gold wire L4.

3. The low-noise amplifier device in the liquid nitrogen temperature range according to claim 1, characterized in that: The first-stage die unit is bonded to GaAs via gold wire L1 bonding. The gate of the pHEMT die T1 is connected to the drain of the GaAspHEMT die T1 via a gold wire L2. One end of the input DC blocking capacitor C1 is connected to the RF input signal, and the other end is connected to the gold wire L1. The gate bias circuit of T1 consists of Lp1 and Cp1. One end of Lp1 is connected to the gold wire L1 and C1 via a microstrip line, and the other end is connected to Cp1 and the first-stage power supply. The other end of Cp1 is grounded. The drain bias circuit of T1 consists of Lp2, Cp2 and Rp1. One end of Lp2 is connected to the gold wire L2 via a microstrip line, and the other end is connected to Cp2 and Rp1. The other end of Cp2 is grounded. The other end of Rp1 is connected to the second-stage power supply. The RLC feedback circuit consists of Lf1, Rf1 and Cf1. One end of Lf1 is connected to the gold wire L1, and the other end is connected to Rf1. The other end of Rf1 is connected to Cf1, and the other end of Cf1 is connected to Lp2. The first-stage power supply is a DC power supply, used to provide voltage Vgs1 to the gate of the first-stage amplifier. The second-stage power supply is a DC power supply, used to provide voltage Vds1 to the drain of the first-stage amplifier.

4. A low-noise amplifier device in the liquid nitrogen temperature range according to claim 1, characterized in that: The second-stage die unit is bonded to the gate of the GaAs pHEMT die T2 via gold wire L3, and gold wire L4 is bonded to the drain of the GaAs pHEMT die T2. The gate bias circuit of T2 consists of Lp3 and Cp3. One end of Lp3 is connected to gold wires L3 and C3 via a microstrip line, and the other end is connected to Cp3 and the third-stage power supply. The other end of Cp3 is grounded. The drain bias circuit of T2 consists of Lp4, Cp4, and Rp2. One end of Lp4 is connected to gold wire L4 via a microstrip line, and the other end is connected to Cp4 and Rp2. The other end of Cp2 is grounded, and the other end of Rp2 is connected to the fourth-stage power supply. The RLC feedback circuit consists of Lf2, Rf2, and Cf2. One end of Lf2 is connected to gold wire L3, and the other end is connected to Rf2. The other end of Rf2 is connected to Cf2, and the other end of Cf2 is connected to Lp4. The third-stage power supply is a DC power supply, used to provide the gate voltage Vgs2 of the second-stage amplifier. The fourth stage power supply is a DC power supply, which provides voltage Vds2 to the drain of the second stage amplifier.

5. The low-noise amplifier device in the liquid nitrogen temperature range according to claim 1, characterized in that: The interstage matching circuit includes C2, C3, and L1. One end of C2 is connected to the output of the first-stage amplifier, and the other end is connected to one end of L1 and C3. The other end of L1 is grounded. The other end of C3 is connected to the input of the second-stage amplifier.

6. The low-noise amplifier device in the liquid nitrogen temperature range according to claim 1, characterized in that: The output matching circuit includes C4, C5, and L2. One end of C4 is connected to the output of the second-stage amplifier, and the other end is connected to one end of L2 and C4. The other end of L2 is grounded. The other end of C4 is connected to the RF output.

7. A low-noise amplifier device in the liquid nitrogen temperature range according to claim 3, characterized in that, Resistors Rp1, Rp2, Rf1, and Rf2 are all thin-film resistors.

8. The low-noise amplifier device in the liquid nitrogen temperature range according to claim 3, characterized in that, Filter capacitors Cp1, Cp2, Cp3, and Cp4, as well as input DC blocking capacitors C1, C2, C3, C4, and C5, are all surface-mount capacitors in 0402 packages.

9. The low-noise amplifier device in the liquid nitrogen temperature range according to claim 3, characterized in that, The resistors Rp1, Rp2, Rf1, and Rf2 are all surface mount resistors in 0402 packages.

10. A low-noise amplifier device in the liquid nitrogen temperature range according to claim 1, characterized in that, Both die T1 and die T2 are enhanced E-pHEMT.

Images