WO2022099908A1

WO2022099908A1 - High-performance millimeter-wave low-noise composite amplifier

Info

Publication number: WO2022099908A1
Application number: PCT/CN2020/142375
Authority: WO
Inventors: 陈志坚; 邹宇; 李斌
Original assignee: 华南理工大学
Priority date: 2020-11-11
Filing date: 2020-12-31
Publication date: 2022-05-19
Also published as: CN112290894B; CN112290894A

Abstract

Disclosed is a high-performance millimeter-wave low-noise composite amplifier, which relates to a communication technology device. The present solution is proposed for solving problems in the existing technology, such as large off-chip interference of amplifiers and low gain flatness. The amplifier comprises: two cascode amplifying units having the same structure provided in series connection. An input stage of a cascode amplifying unit at a front end is connected to an input pad GSG1 by means of a capacitor C1, an output stage of a cascode amplifying unit at a back end is connected to an output pad GSG2 by means of a capacitor C5, and a capacitor C4 forms a series connection between the two cascode amplifying units. Advantageously, the comprehensive design of the two-stage cascode amplifying units using a corresponding input matching circuit, output matching circuit and cascode matching circuit improve the gain, bandwidth and gain flatness of the millimeter-wave low-noise amplifier.

Description

A high-performance millimeter-wave low-noise composite amplifier

technical field

The invention relates to communication technology equipment, in particular to a high-performance millimeter-wave low-noise composite amplifier.

Background technique

Millimeter-wave low-noise amplifiers are an important module in 5G communication radio frequency chips. They are widely used in automotive radar, precision guidance, and satellite communications. They will also enter the field of civil communication in the future. At present, millimeter-wave communication integrated circuits have become the key research content of high-tech industries in various countries. Its characteristics of large data throughput and short communication delay can greatly improve the combat capability of high-tech defense weapons, and can promote no-failure in the field of intelligent transportation. The reliable realization of human-driven vehicles can improve the work efficiency of users in the field of civil communication. The frequency range of millimeter wave is 26.5-300GHz. The RF chips designed in this frequency band mainly face the problems of self-excited oscillation, large off-chip interference, low gain, insufficient bandwidth and low gain flatness, which further lead to insufficient performance of the finished chip. Poor stability, etc. Therefore, designing high-performance millimeter-wave amplifiers is the key to improving the stability of communication chips.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a high-performance millimeter-wave low-noise composite amplifier to solve the above-mentioned problems in the prior art.

A high-performance millimeter-wave low-noise compound amplifier according to the present invention includes two cascode amplifying units arranged in series and having the same structure. Disk GSG1, the output stage of the rear cascode amplifying unit is connected to the output pad GSG2 through a capacitor C5; a capacitor C4 is connected in series between the two cascode amplifying units;

The cascode amplifying unit mainly includes a MOS tube M1 and a MOS tube M2 arranged in cascade: the gate of the MOS tube M1 is preceded by an input matching circuit as an input stage, and the voltage end of the input matching circuit is biased by the front-stage gate. The set circuit is connected to the DC pad Vg1; the source of the MOS tube M1 is grounded through the microstrip line TLs; the gate of the MOS tube M2 is connected to the DC pad Vg2 through the subsequent gate bias circuit; the drain of the MOS tube M2 is set to the output matching circuit as In the output stage, the voltage terminal of the output matching circuit is connected to the DC pad Vd through the drain bias circuit; a cascode matching circuit is connected in series between the drain of the MOS transistor M1 and the source of the MOS transistor M2.

The front-stage gate bias circuit includes a capacitor Cd3 and a resistor Rd2; one end of the capacitor Cd3 is grounded, and the other end is connected to the DC pad Vg1 and the voltage terminal of the input matching circuit through the resistor Rd2.

The input matching circuit includes a capacitor Cd1, a capacitor Cd2, a resistor Rd1, a microstrip line TLd1, a microstrip line TL1 and a microstrip line TL2; one end of the resistor Rd1 is used as a voltage terminal to connect to the front-stage gate bias circuit, The other end is grounded through the capacitor Cd2; the voltage end is also grounded through the capacitor Cd1; the microstrip line TLd1, the microstrip line TL1 and the microstrip line TL2 have a common point to form a T-shaped structure, and the non-common point end of the microstrip line TLd1 is connected to the voltage The non-common-point end of the microstrip line TL1 is the input end of the input matching circuit, and the non-common-point end of the microstrip line TL2 is connected to the gate of the MOS transistor M1.

The cascode matching circuit includes a capacitor C2, a microstrip line TL3 and a microstrip line TL4; the drain of the MOS tube M1 is connected in series with the microstrip line TL3 and the microstrip line TL4 in sequence, and then connected to the source of the MOS tube M2, and the microstrip line TL4 is connected to the source of the MOS tube M2. The connection point of the strip line TL3 and the microstrip line TL4 is grounded through the capacitor C2.

The latter-stage gate bias circuit includes a capacitor Cd4 and a resistor Rd3; one end of the capacitor Cd4 is grounded, and the other end is connected to the DC pad Vg2 and the gate of the MOS transistor M2 through the resistor Rd3.

The drain bias circuit includes a capacitor Cd5 and an inductor L1; one end of the capacitor Cd5 is grounded, and the other end is connected to the DC pad Vd and the voltage terminal of the output matching circuit through the inductor L1.

The output matching circuit includes a capacitor Cd7, a capacitor Cd6, a resistor Rd4, a microstrip line TLd2, a microstrip line TL6 and a microstrip line TL7; one end of the resistor Rd4 is connected to the drain bias circuit as a voltage end, and the other end is connected to the drain bias circuit. The voltage terminal is grounded through the capacitor Cd6; the voltage terminal is also grounded through the capacitor Cd7; the microstrip line TLd2, the microstrip line TL6 and the microstrip line TL7 have a common point to form a T-shaped structure, and the non-common point end of the microstrip line TLd2 is connected to the voltage terminal, The non-common-point end of the microstrip line TL6 is connected to the drain of the MOS transistor M2, and the non-common-point end of the microstrip line TL7 is the output end of the output matching circuit.

The advantage of the high-performance millimeter-wave low-noise composite amplifier of the present invention lies in that the two-stage cascode amplifying unit is supplemented by the corresponding input matching circuit, output matching circuit and inter-stage matching circuit. Improved mmWave LNA gain, bandwidth, and gain flatness. Further, the T-shaped design inside the cascode matching circuit improves the high frequency stability of the cascode amplifying unit. The LC isolation network designed in the drain bias circuit shields off-chip power supply noise, prevents the bond wire from deteriorating performance, and facilitates the routing of the power supply lines.

Description of drawings

Fig. 1 is the principle block diagram of the composite amplifier of the present invention;

2 is a structural block diagram of the cascode amplifying unit;

FIG. 3 is a schematic structural diagram of the composite amplifier according to the present invention.

Fig. 4 is the graph of the gain electromagnetic simulation result of the composite amplifier of the present invention;

Fig. 5 is the electromagnetic simulation result graph of the return loss of the composite amplifier of the present invention;

Fig. 6 is the noise figure electromagnetic simulation result graph of the composite amplifier of the present invention;

FIG. 7 is a graph showing the stability of the electromagnetic simulation result of the composite amplifier of the present invention.

Detailed ways

As shown in Figures 1-3, a high-performance millimeter-wave low-noise composite amplifier according to the present invention includes two cascode amplifying units arranged in series and having the same structure, and the front-end cascode amplifying unit inputs The stage is connected to the input pad GSG1 through the capacitor C1, and the output stage of the rear cascode amplifying unit is connected to the output pad GSG2 through the capacitor C5. The output stage of the front-end cascode amplifying unit is connected to the input stage of the back-end cascode amplifying unit through the capacitor C4.

The cascode amplifying unit mainly includes a MOS tube M1 and a MOS tube M2 arranged in cascade: the gate of the MOS tube M1 is preceded by an input matching circuit as an input stage, and the voltage end of the input matching circuit is biased by the front-stage gate. Set the circuit to connect the DC pad Vg1. The source of the MOS transistor M1 is grounded through the microstrip line TLs. The gate of the MOS transistor M2 is connected to the DC pad Vg2 through the gate bias circuit of the subsequent stage. The drain of the MOS transistor M2 is followed by an output matching circuit as an output stage, and the voltage end of the output matching circuit is connected to the DC pad Vd through the drain bias circuit. A cascode matching circuit is connected in series between the drain of the MOS transistor M1 and the source of the MOS transistor M2.

The front-stage gate bias circuit includes a capacitor Cd3 and a resistor Rd2. One end of the capacitor Cd3 is grounded, and the other end is connected to the DC pad Vg1 and the voltage terminal of the input matching circuit through the resistor Rd2.

The input matching circuit includes a capacitor Cd1, a capacitor Cd2, a resistor Rd1, a microstrip line TLd1, a microstrip line TL1 and a microstrip line TL2. One end of the resistor Rd1 is connected to the front-stage gate bias circuit as a voltage end, and the other end is grounded through the capacitor Cd2. The voltage terminal is also grounded through the capacitor Cd1. The microstrip line TLd1, the microstrip line TL1 and the microstrip line TL2 have a common point to form a T-shaped structure, the non-common point end of the microstrip line TLd1 is connected to the voltage terminal, and the non-common point end of the microstrip line TL1 is an input matching circuit The non-common point end of the microstrip line TL2 is connected to the gate of the MOS transistor M1.

The cascode matching circuit includes a capacitor C2, a microstrip line TL3 and a microstrip line TL4. The drain of the MOS transistor M1 is connected in series with the microstrip line TL3 and the microstrip line TL4 once and then connected to the source of the MOS transistor M2. The connection point of the microstrip line TL3 and the microstrip line TL4 is grounded through the capacitor C2.

The post-stage gate bias circuit includes a capacitor Cd4 and a resistor Rd3. One end of the capacitor Cd4 is grounded, and the other end is connected to the DC pad Vg2 and the gate of the MOS transistor M2 through the resistor Rd3.

The drain bias circuit includes a capacitor Cd5 and an inductor L1. One end of the capacitor Cd5 is grounded, and the other end is connected to the DC pad Vd and the voltage end of the output matching circuit through the inductor L1.

The output matching circuit includes a capacitor Cd7, a capacitor Cd6, a resistor Rd4, a microstrip line TLd2, a microstrip line TL6 and a microstrip line TL7. One end of the resistor Rd4 is connected to the drain bias circuit as a voltage end, and the other end is grounded through the capacitor Cd6. The voltage terminal is also grounded through the capacitor Cd7. The microstrip line TLd2, the microstrip line TL6 and the microstrip line TL7 form a T-shaped structure in common. The drain, the non-common point end of the microstrip line TL7 is the output end of the output matching circuit.

The optimization principle of a high-performance millimeter-wave low-noise composite amplifier according to the present invention is as follows:

Improve gain, bandwidth and gain flatness: Through the design of input matching circuit, output matching circuit and cascode matching circuit, the signal reflection of each port of the two-stage cascode amplifier unit is suppressed, and the amplifier bandwidth is improved. The same design of the cascode amplifying unit improves the gain of the single-stage amplifying unit, thereby reducing the number of amplifier stages, reducing the design of the matching circuit, and thus reducing the chip area. The microstrip line TLd and the capacitor Cd1 form an LC band-pass filter network. There is a low-impedance path to ground near the resonance point. Low-frequency signals can be leaked to the ground through this path, thereby suppressing the low-frequency gain of the composite amplifier and improving the in-band gain. Gain flatness. The electromagnetic simulation results of the gain of the compound amplifier are shown in Figure 4, the electromagnetic simulation results of the return loss are shown in Figure 5, and the electromagnetic simulation results of the noise figure are shown in Figure 6.

The TLd on each bias and the corresponding parallel capacitors Cd1, Cd3, etc. have this function.

Improve stability: Design a T-type matching circuit inside the cascode amplifying unit, and the microstrip lines TL3 and TL4 can improve the output impedance to optimize the output matching of the cascode amplifying unit, reduce reflection, and ultimately suppress self-oscillation. Capacitor C2 provides a low-impedance path for short-circuiting high-frequency signals to ground. This capacitor mainly short-circuits high-frequency noise from 40 to 100 GHz to ground to prevent high-frequency noise outside the frequency band from being amplified to form self-excited oscillation, resulting in instability. Figure 7 shows the stable electromagnetic simulation results of the composite amplifier after the introduction of the cascode internal T-type matching network.

Shield off-chip power supply noise interference, prevent bond wire from deteriorating performance, and simplify power supply line wiring: Introduce LC isolation network in the drain bias circuit, where the series inductor L1 acts as a high-impedance choke coil to prevent external noise current from entering the matching circuit, and at the same time Prevents the current signal of the matching circuit from leaking off-chip, thereby deteriorating the matching. The capacitor Cd5 connected in parallel to the ground uses its self-resonance effect to form a low-impedance grounding path near the resonant frequency, which can short-circuit the off-chip noise voltage to the ground and improve the anti-interference ability. The LC isolation network cuts off the coupling path of the RF signals on and off the chip. Since the signals in the matching circuit have been isolated by the LC network, RF signals do not flow into the power lines, so the power lines can be routed freely without causing mismatches in the matching network.

For those skilled in the art, various other corresponding changes and deformations can be made according to the technical solutions and concepts described above, and all these changes and deformations should fall within the protection scope of the claims of the present invention.

Claims

A high-performance millimeter-wave low-noise compound amplifier is characterized by comprising two cascode amplifying units arranged in series and having the same structure, and the input stage of the front-end cascode amplifying unit is connected to an input pad through a capacitor C1 GSG1, the output stage of the rear cascode amplifying unit is connected to the output pad GSG2 through the capacitor C5; the capacitor C4 is connected in series between the two cascode amplifying units;

The cascode amplifying unit mainly includes a MOS transistor M1 and a MOS transistor M2 arranged in cascade:

The gate of the MOS transistor M1 is preceded by an input matching circuit as an input stage, and the voltage end of the input matching circuit is connected to the DC pad Vg1 through the gate bias circuit of the previous stage; the source of the MOS transistor M1 is grounded through the microstrip line TLs;

The gate of the MOS transistor M2 is connected to the DC pad Vg2 through the gate bias circuit of the rear stage; the drain of the MOS transistor M2 is set to an output matching circuit as the output stage, and the voltage end of the output matching circuit is connected to the DC welding pad through the drain bias circuit. disk Vd;

A cascode matching circuit is connected in series between the drain of the MOS transistor M1 and the source of the MOS transistor M2.
The high-performance millimeter-wave low-noise composite amplifier according to claim 1, wherein the front-stage gate bias circuit comprises a capacitor Cd3 and a resistor Rd2; one end of the capacitor Cd3 is grounded, and the other end is connected to DC The pad Vg1 is connected to the voltage terminal of the input matching circuit through the resistor Rd2.
The high-performance millimeter-wave low-noise composite amplifier according to claim 1, wherein the input matching circuit comprises a capacitor Cd1, a capacitor Cd2, a resistor Rd1, a microstrip line TLd1, a microstrip line TL1 and a microstrip line TL2 ; One end of the resistor Rd1 is connected to the front-stage gate bias circuit as a voltage terminal, and the other end is grounded through the capacitor Cd2; the voltage terminal is also grounded through the capacitor Cd1; the microstrip line TLd1, the microstrip line TL1 and the microstrip line The common point of the strip line TL2 forms a T-shaped structure, the non-common point end of the microstrip line TLd1 is connected to the voltage terminal, the non-common point end of the microstrip line TL1 is the input end of the input matching circuit, and the non-common point end of the microstrip line TL2 is connected to MOS transistor M1 gate.
The high-performance millimeter-wave low-noise compound amplifier according to claim 1, wherein the cascode matching circuit comprises a capacitor C2, a microstrip line TL3 and a microstrip line TL4; the MOS transistor M1 drains The microstrip line TL3 and the microstrip line TL4 are connected to the source of the MOS transistor M2 once in series, and the connection point of the microstrip line TL3 and the microstrip line TL4 is grounded through the capacitor C2.
The high-performance millimeter-wave low-noise composite amplifier according to claim 1, wherein the post-stage gate bias circuit comprises a capacitor Cd4 and a resistor Rd3; one end of the capacitor Cd4 is grounded, and the other end is connected to DC The pad Vg2 is connected to the gate of the MOS transistor M2 through the resistor Rd3.
The high-performance millimeter-wave low-noise composite amplifier according to claim 1, wherein the drain bias circuit comprises a capacitor Cd5 and an inductor L1; one end of the capacitor Cd5 is grounded, and the other end is connected to the DC pad Vd and the voltage terminal of the output matching circuit is connected through the inductor L1.
The high-performance millimeter-wave low-noise composite amplifier according to claim 1, wherein the output matching circuit comprises a capacitor Cd7, a capacitor Cd6, a resistor Rd4, a microstrip line TLd2, a microstrip line TL6 and a microstrip line TL7 One end of the resistor Rd4 is connected to the drain bias circuit as a voltage terminal, and the other end is grounded through the capacitor Cd6; the voltage terminal is also grounded through the capacitor Cd7; the microstrip line TLd2, the microstrip line TL6 and the microstrip line are grounded; The common point of TL7 forms a T-shaped structure, the non-common point end of the microstrip line TLd2 is connected to the voltage terminal, the non-common point end of the microstrip line TL6 is connected to the drain of the MOS transistor M2, and the non-common point end of the microstrip line TL7 is output matching output of the circuit.