WO2023109425A1

WO2023109425A1 - Power amplifier and radio frequency chip

Info

Publication number: WO2023109425A1
Application number: PCT/CN2022/132749
Authority: WO
Inventors: 张莽; 郭嘉帅
Original assignee: 深圳飞骧科技股份有限公司
Priority date: 2021-12-17
Filing date: 2022-11-18
Publication date: 2023-06-22
Also published as: CN216649629U

Abstract

Embodiments of the present application provide a power amplifier. The power amplifier comprises an amplification circuit and a bias circuit, the amplification circuit comprising amplification circuit units; the power amplifier is provided with a common connection line in a circuit layout, and a connection point between the bias circuit and the common connection line is a common connection point; the amplification circuit units are arranged side by side in the circuit layout, and a connection point between a second input end of each amplification circuit unit and the common connection line is a bias voltage connection point; the common connection line comprises a first section and a second section, and the common connection point is provided in the middle of the common connection line; and the number of bias voltage connection points in the first section is the same as that of bias voltage connection points in the second section, and each bias voltage connection point in the first section and one bias voltage connection point in the second section are symmetrically arranged by using the common connection point as the center. The embodiments of the present application further provide a radio frequency chip applying the power amplifier. By using the technical solution of the present application, the working performance of the circuit is good.

Description

Power Amplifier and RF Chip

technical field

The utility model relates to the technical field of amplifier circuits, in particular to a power amplifier and a radio frequency chip.

Background technique

At present, with the rapid development of semiconductor technology, integrated circuits have been used in various fields, among which power amplifiers are often used to amplify various analog signals, and are important components in analog circuit applications.

A power amplifier in the related art generally includes an amplifying circuit and a bias circuit that provides a bias voltage to the amplifying circuit. In the circuit of the power synthesizing power amplifier with a differential structure, the amplifying circuit is generally the final stage amplifying unit, and the final stage amplifying unit generally consists of more than 30 HBT transistors (English Bipolar Junction Transistor, referred to as BJT) and more than 30 bias transistors. Set resistors to form more than 30 amplifier units. An HBT transistor and a bias resistor respectively form an amplifying circuit unit, and more than 30 amplifying circuit units are symmetrically combined in parallel to form the amplifying circuit. As shown in FIG. 1 , FIG. 1 is a circuit layout of a related art power amplifier. Among them, A is the circuit layout of the bias circuit; B is the common connection point between the bias circuit and all amplifying circuit units; C is the connection point of an amplifying circuit unit closest to the common connection point B; D is the distance from the common connection point B The connection point of the farthest amplifying circuit unit. The connection point B, the connection point C and the connection point D are all electrically connected through metal connection wires.

However, in the power amplifier of the related art, the asymmetry of the connection point between the bias circuit and the amplifying circuit unit will cause the actual bias resistance value of the amplifying circuit unit to be different. For example, the length of the metal connection line from point B to point D is about 300um, and the length of the metal connection line from point B to point C is about 10um. The thickness of the bias resistor connecting line from point B to each amplifying circuit unit is 2um, the width is generally about 4um, the resistance value of the connecting line per unit length is about 0.008 ohm/micron, and the equivalent resistance from point B to point D is about 0.008x300＝2.4 ohm. At the same time, considering that the connection point between the first layer of metal and the second layer of metal in the circuit layout will also increase the additional resistance value, the actual equivalent resistance is greater than 2.4 ohms, which is much greater than the equivalent resistance value from point B to point C. In a differential structure power combining power amplifier, this phenomenon is more serious due to the large number of amplifying circuit units. In addition, since all amplifying circuit units are connected in parallel, multiple bias resistors are also connected in parallel, which greatly reduces the equivalent bias resistance of the entire final stage power amplifying circuit. For example, assuming that the bias resistance R=300 ohm of all amplifying circuit units, and the number of amplifying circuit units is 30, the entire power amplifying circuit is equivalent to The bias resistor Rs≈10 ohms. Therefore, due to the large number of amplifying circuit units and the large circuit layout area, the resulting bias resistors have large differences in value, which will aggravate the uneven current distribution in all amplifying circuit units and affect circuit reliability and amplifier performance. Due to the influence of temperature when the power amplifier is working, the bias voltage provided by the bias circuit will fluctuate to a certain extent, and it is not a fixed value. Since the equivalent bias resistance Rs is very small, the working state of the entire power amplifier circuit is greatly affected by the fluctuation of the bias voltage, and the working state is unstable, resulting in low performance of the power amplifier.

Therefore, it is necessary to provide a new power amplifier and radio frequency chip to solve the above problems.

Utility model content

Aiming at the above deficiencies in the prior art, the utility model proposes a power amplifier and a radio frequency chip with good circuit performance.

In order to solve the above technical problems, in the first aspect, the embodiment of the utility model provides a power amplifier, which includes an amplifying circuit and a bias circuit that provides a bias voltage to the amplifying circuit, and the amplifying circuit includes a plurality of mutual Amplifying circuit units arranged in parallel; the first input terminals of each of the amplifying circuit units are connected to each other and used as the input terminals of the amplifying circuit, and the second input terminals of each of the amplifying circuit units are connected to the bias set circuit, the output terminals of each of the amplifying circuit units are connected to each other and serve as the output terminals of the amplifying circuit;

There are N amplifying circuit units, and N is an even number;

The power amplifier is provided with a common connection line on the circuit layout, and the connection point between the bias circuit and the common connection line is a common connection point;

The amplifying circuit units are arranged side by side on the circuit layout, the second input end is connected to the common connection line, the connection point between the second input end and the common connection line is a bias connection point, and each The bias connection point corresponds to one of the amplifying circuit units;

The common connection line includes a first segment and a second segment, the common connection point is arranged in the middle of the common connection line, and the first segment and the second segment are connected through the common connection point; The number of the bias connection points in the first section is the same as the number of the bias connection points in the second section, and each of the bias connection points in the first section is respectively connected to the One of the bias connection points in the second segment is arranged symmetrically with respect to the common connection point.

Preferably, N≤8.

Preferably, the amplifying circuit includes multiple, the biasing circuit includes multiple, and each amplifying circuit is correspondingly connected to one of the biasing circuits.

Preferably, N is 8, the amplifying circuits include 4, and the bias circuits include 4.

Preferably, the common connecting wire is a rectangular metal wire.

Preferably, the amplifying circuit unit includes capacitors, resistors and transistors;

The first terminal of the capacitor is used as the first input terminal, and the first terminal of the capacitor is respectively connected to the second terminal of the resistor and the base of the transistor;

The second end of the resistor is used as the second input end, and the second end of the resistor is connected to the bias voltage;

The collector of the transistor is used as the output terminal of the amplifying circuit unit, and the collector of the transistor is connected to the power supply voltage; the emitter of the transistor is connected to the ground.

Preferably, the transistor is a bipolar junction transistor.

In the second aspect, the embodiment of the present invention further provides a radio frequency chip, the radio frequency chip is like the above-mentioned power amplifier provided by the embodiment of the present invention.

Compared with the related technology, the power amplifier of the utility model embodiment sets the connection point of the bias circuit and the common connection line as the common connection point, and sets the connection point of the second input terminal of the amplifying circuit unit and the common connection line as the bias voltage connection point; and the public connection line is divided into the first section and the second section, the public connection point is set in the middle of the public connection line, the number of bias connection points in the first section is the same as the number of bias connection points in the second section Similarly, each bias connection point in the first section is arranged symmetrically with one of the bias connection points in the second section with the common connection point as the center. This setting makes the length of each bias connection point in the common connection line close, and will not cause a large difference in the bias resistance in the amplifying circuit unit, thus solving the circuit reliability problem caused by the asymmetry of the bias connection point and amplifier performance degradation issues. Therefore, the circuit performance of the power amplifier and the operational amplifier of the radio frequency chip in the embodiment of the utility model is good.

Description of drawings

Below in conjunction with accompanying drawing, describe the utility model in detail. Through the detailed description in conjunction with the following drawings, the content of the above or other aspects of the present invention will become clearer and easier to understand. In the attached picture,

Fig. 1 is the circuit layout of the power amplifier of related art;

Fig. 2 is the circuit layout of the power amplifier of the utility model embodiment;

Fig. 3 is the circuit structure diagram of the power amplifier of the utility model embodiment;

Fig. 4 is a circuit structure diagram of the amplifying circuit unit of the embodiment of the present invention.

Detailed ways

The specific embodiment of the utility model will be described in detail below in conjunction with the accompanying drawings.

The specific implementations/embodiments described here are specific specific implementations of the present utility model, and are used to illustrate the concept of the present utility model. Limitations on the scope of utility models. In addition to the embodiments described here, those skilled in the art can also adopt other obvious technical solutions based on the claims of the application and the contents disclosed in the description, and these technical solutions include adopting any obvious changes made to the embodiments described here. The replacement and modified technical solutions are all within the protection scope of the present utility model.

(first embodiment)

The utility model provides a power amplifier 100 .

Please refer to shown in Fig. 2-4 at the same time, Fig. 2 is the circuit layout of the power amplifier of the utility model embodiment; Fig. 3 is the circuit structure diagram of the power amplifier of the utility model embodiment; Fig. 4 is the utility model embodiment The circuit structure diagram of the amplification circuit unit.

A power amplifier 100. It includes an amplifying circuit 1 and a bias circuit 2 providing a bias voltage Vias to the amplifying circuit 1 . The power amplifier 100 is a differential structure power combining power amplifier.

The amplifying circuit 1 includes a plurality of amplifying circuit units 3 arranged in parallel with each other.

The first input terminals of each amplifying circuit unit 3 are connected to each other and serve as the input terminal PIN of the amplifying circuit 1 . The second input terminal of each amplifying circuit unit 3 is connected to the bias voltage Vias. The output terminals of each amplifying circuit unit 3 are connected to each other and serve as the output terminal POUT of the amplifying circuit 1 .

Specifically, the amplifying circuit unit 3 includes a capacitor C, a resistor R and a transistor Q. The transistor Q is a bipolar junction transistor (Bipolar Junction Transistor, BJT for short). Wherein, the capacitor C is used as the input matching capacitor of the amplifying circuit unit 3, and the capacitor C is used to realize the function of a DC blocking capacitor; the resistor R is used as a bias resistor of the amplifying circuit unit 3;

The circuit connection relationship of the amplifying circuit unit 3 is:

The first terminal of the capacitor C is used as the first input terminal. The first terminal of the capacitor C is respectively connected to the second terminal of the resistor R and the base of the transistor Q.

The second end of the resistor R is used as the second input end. And the second end of the resistor R is connected to the bias circuit 2 . That is, the second end of the resistor R receives the bias voltage Vias provided by the bias circuit 2 .

The collector of the transistor Q serves as the output terminal of the amplifying circuit unit 3 . And the collector of the transistor Q is connected to the power supply voltage VDD. The emitter of the transistor Q is connected to the ground GND.

There are N amplifying circuit units 3 . N is an even number. Among them, N≤8.

In this embodiment, N is 8. That is, the amplifying circuit 1 includes 8 amplifying circuit units 3 arranged in parallel with each other. The 8 amplifying circuit units 3 are conducive to the symmetry of the circuit layout of the amplifying circuit unit 3, and are more conducive to shortening the distance connected to the bias circuit 2. The length of the metal connection wire.

Each of the eight amplifying circuit units 3 includes a resistor R. Specifically, the resistor R1, the resistor R2, the resistor R3, the resistor R4, the resistor R5, the resistor R6, the resistor R7 and the resistor R8 are arranged in sequence. The resistors R1 , R2 , R3 , R4 , R5 , R6 , R7 and R8 are all used as bias resistors in the amplifying circuit unit 3 . Eight parallel amplifying circuit units 3 and one bias circuit 2 can form a power amplifier 100 .

In this embodiment, the amplifying circuit 1 includes multiple. The bias circuit 2 includes a plurality of. Of course, it is not limited thereto, and in another embodiment, the amplifier circuit 1 includes multiple. The bias circuit 2 includes a plurality of. Each amplifying circuit 1 is correspondingly connected to one biasing circuit 2 . For example, the amplifying circuit 1 includes four. The bias circuit 2 includes four. That is, there are 32 amplifier circuit units 3 .

The power amplifier 100 is provided with a common connection line L on the circuit layout. In this embodiment, the common connection line L is a rectangular metal line.

The connection point between the bias circuit 2 and the common connection line L is the common connection point E.

The amplifying circuit units 3 are arranged side by side on the circuit layout. The second input terminal is connected to the common connection line L. The connection point between the second input end and the common connection line L is a bias voltage connection point. Each bias connection point corresponds to one amplifying circuit unit 3 . Wherein, the second input end is one end of the connection between the resistor R and the common connection line L.

In this embodiment, the bias connection points are arranged in order of connection point T1, connection point T2, connection point T3, connection point T4, connection point T5, connection point T6, connection point T7 and connection point T8, wherein the resistor R1 The bias connection point connected to the common connection line L is correspondingly the connection point T1; the bias connection point connected to the common connection line L by the resistor R2 is correspondingly the connection point T2; the resistor R3 is connected to the common connection line L The bias connection point of the resistor R4 is connected to the connection point T3; the bias connection point of the resistor R4 connected to the common connection line L is corresponding to the connection point T4; the bias connection point of the resistor R5 connected to the common connection line L is corresponding to the connection point Point T5; the bias connection point where the resistor R6 is connected to the common connection line L is correspondingly the connection point T6; the bias connection point where the resistor R7 is connected to the common connection line L is correspondingly the connection point T7; the resistance R8 is connected to the The bias connection point of the common connection line L is correspondingly the connection point T8.

The common connection line L includes a first segment L1 and a second segment L2. The common connection point E is disposed in the middle of the common connection line L. And the first section L1 and the second section L2 are connected through the common connection point E. The number of the bias connection points in the first section L1 is the same as the number of the bias connection points in the second section L2.

In this embodiment, the connection point T1, the connection point T2, the connection point T3, and the connection point T4 are located in the first segment L1. The connection point T5, the connection point T6, the connection point T7 and the connection point T8 are located in the second section L2.

Each of the bias connection points located in the first section L1 is respectively arranged symmetrically with one of the bias connection points located in the second section L2 with the common connection point E as the center. This setting makes the length of each bias connection point in the common connection line L close, and will not cause a large difference in the bias resistance in the amplifying circuit unit 3, thereby solving the problem of circuit reliability caused by the asymmetry of the bias connection point. Sexuality issues and amplifier performance degradation issues.

In this embodiment, the total resistance R of all amplifying circuit units 3 is 300 ohms, and the number of amplifying circuit units 3 is 8. The amplifying circuit composed of these 8 amplifying circuit units 3 is viewed from the common connection point E as a base point. 1. The equivalent bias resistance Rs of the amplifying circuit 1 is about 37.5 ohms. The equivalent bias resistance Rs of the amplifying circuit 1 is much larger than the equivalent bias resistance Rs of about 10 ohms in the background art. Therefore, the equivalent bias resistance Rs of the amplifying circuit 1 is larger, and the circuit working state of the power amplifier 100 is more stable than that of the power amplifier in the background art, thereby improving the reliability of the power amplifier 100 and optimizing the performance of the amplifier.

In another embodiment, if there are 32 amplifying circuit units 3 in the power amplifier 100 of differential structure power combining, then four such amplifying circuits 1 are required.

It should be pointed out that the relevant bias circuits, amplifier circuits, capacitors, transistors and resistors used in the utility model are all circuits and components commonly used in this field, and the specific indicators and parameters corresponding to the circuits and components can be determined according to actual applications. The adjustment is not described in detail here.

The embodiment of the utility model also provides a radio frequency chip. The radio frequency chip includes the power amplifier 100 .

It should be noted that the various embodiments described above with reference to the accompanying drawings are only used to illustrate the utility model rather than limit the scope of the utility model, those of ordinary skill in the art should understand that without departing from the spirit and scope of the utility model Any modifications or equivalent replacements made to the present utility model under the premise of the present utility model shall be covered within the scope of the present utility model. Further, words appearing in the singular include the plural and vice versa unless the context otherwise requires. Additionally, all or a portion of any embodiment may be utilized with all or a portion of any other embodiment, unless stated otherwise.

Claims

A power amplifier comprising an amplifying circuit and a bias circuit providing a bias voltage to the amplifying circuit, the amplifying circuit comprising a plurality of amplifying circuit units arranged in parallel with each other; the first input of each amplifying circuit unit terminals are connected to each other and used as the input terminal of the amplifying circuit, the second input terminal of each amplifying circuit unit is connected to the bias circuit, and the output terminals of each amplifying circuit unit are connected to each other and used as the input terminal of the amplifying circuit unit. The output terminal of the amplifying circuit; it is characterized in that,

There are N amplifying circuit units, and N is an even number;

The power amplifier is provided with a common connection line on the circuit layout, and the connection point between the bias circuit and the common connection line is a common connection point;

The amplifying circuit units are arranged side by side on the circuit layout, the second input end is connected to the common connection line, the connection point between the second input end and the common connection line is a bias connection point, and each The bias connection point corresponds to one of the amplifying circuit units;

The common connection line includes a first segment and a second segment, the common connection point is arranged in the middle of the common connection line, and the first segment and the second segment are connected through the common connection point; The number of the bias connection points in the first section is the same as the number of the bias connection points in the second section, and each of the bias connection points in the first section is respectively connected to the One of the bias connection points in the second segment is arranged symmetrically with respect to the common connection point.
The power amplifier according to claim 1, characterized in that N≤8.
The power amplifier according to claim 2, wherein the amplifying circuits include multiple, the bias circuits include multiple, and each of the amplifying circuits is correspondingly connected to one of the bias circuits.
The power amplifier according to claim 3, wherein N is 8, said amplifying circuits include 4, and said bias circuits include 4.
The power amplifier according to claim 1, wherein the common connection line is a rectangular metal line.
The power amplifier according to claim 1, wherein the amplifying circuit unit comprises a capacitor, a resistor and a transistor;

The first terminal of the capacitor is used as the first input terminal, and the first terminal of the capacitor is respectively connected to the second terminal of the resistor and the base of the transistor;

The second end of the resistor is used as the second input end, and the second end of the resistor is connected to the bias voltage;

The collector of the transistor is used as the output terminal of the amplifying circuit unit, and the collector of the transistor is connected to the power supply voltage; the emitter of the transistor is connected to the ground.
The power amplifier according to claim 5, wherein the transistor is a bipolar junction transistor.
A radio frequency chip, characterized in that the radio frequency chip comprises the power amplifier according to any one of claims 1-7.