KR100962405B1 - Power Amplifier With Internal Matching Network - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power amplifier having a matching circuit, and more particularly, to a power amplifier having an internal PI matching circuit including a capacitor having a high conductivity material and a wired inductor.

An amplifier having an internal PI matching circuit according to the present invention includes a two stage internal PI matching circuit in which a PI matching circuit composed of two high capacitance capacitors and an inductor positioned between the two high capacitance capacitors is connected in two stages. It is configured to include.

The present invention can miniaturize the size of the matching circuit, thereby reducing the size of the amplifier package. In addition, an additional LC circuit for second harmonic rejection can be implemented inside the package to improve the performance of the power amplifier.

Matching Circuit, Matching Network, Power Amplifier, Power Amp, LC Resonant Circuit

Description

Amplifier with Internal PI Matching Circuit {Power Amplifier With Internal Matching Network}

The present invention relates to a power amplifier having a matching circuit, and in particular, a PI matching circuit is provided inside a package by applying a capacitor and a thin wire welded inductor of a high conductivity material in place of the conventional λ / 4 transmission line. It relates to a power amplifier.

The present invention also relates to a power amplifier having a PI matching circuit and an LC resonant circuit in a package further including an LC resonant circuit in which a high dielectric constant capacitor and a thin wire welding inductor are connected in series.

Recently, as interest in wireless Internet has increased, development of WiBro / WiMAX systems has been actively performed. In particular, power amplifiers for WiBro / WiMAX require relatively high frequency, output power, and wide bandwidth, and thus, power amplifiers using GaN have been actively developed as well as existing power devices.

1 illustrates an equivalent circuit of a conventional broadband power amplifier proposed by Endyna Device Inc. This conventional broadband power amplifier uses a two-stage λ / 4 transmission line as a matching circuit. Since the λ / 4 transmission line is large in size, only one stage is implemented inside the package and the other stage is implemented outside the package. In addition, there is a problem that the size of the entire package is increased because the size of the λ / 4 transmission line implemented in the package is considerable.

In addition, this increase in package size not only increases the size of the entire power amplifier, but also increases the cost of the power amplifier. As the package size increases, additional circuits such as an LC resonant circuit for removing second harmonics can be implemented inside the package. There is a problem.

In order to solve the above problems, the present invention provides a amplifier having a matching circuit inside the package by applying a PI circuit using a high dielectric constant capacitor and a thin wire welded inductor in place of the conventional λ / 4 transmission line. It aims to do it.

In addition, an object of the present invention is to provide a power amplifier having an internal matching circuit and an LC resonant circuit having a multifunction and maintaining a small package size by adding an LC resonant circuit for removing second harmonics.

In order to achieve the above object, a power amplifier having a two stage internal PI matching circuit according to the present invention, a PI matching circuit composed of two high capacitance capacitors and an inductor located between the two high capacitance capacitors in a package. Provides an amplifier containing two stages of internal PI matching circuits in series with two stages.

In this case, the high capacitance capacitor is preferably implemented by stacking a metal pattern on the upper and lower surfaces of the dielectric substrate inserted into the package, and the inductor changes any one of a length, a thickness of a wire, and a material between the pad and the pad. It is desirable to implement a thin wire welding type that can adjust the inductance value.

According to another aspect of the present invention, a power amplifier having an internal PI matching circuit and an LC resonant circuit provides an amplifier including an internal PI matching circuit having two stages and an LC resonant circuit configured by connecting a high capacitance capacitor and an inductor in series. do.

According to the present invention, a PI network implemented by a capacitor using a high-k material and a wired inductor is used to reduce the size of the matching circuit by using an internal matching circuit that replaces a conventional λ / 4 transmission line. This makes the overall package smaller in size.

In addition, the performance of the power amplifier can be further improved by implementing an additional second harmonic cancellation LC circuit inside the package. The miniaturization and versatility of these packages not only makes it easier and more efficient for designers to design power amplifiers, but it also improves reliability by reducing circuitry to be implemented outside the package.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. The following embodiments are provided to those skilled in the art to fully understand the present invention, and may be modified in various forms, and thus the scope of the present invention is not limited to the embodiments described below. . In describing the present invention, when it is determined that description of related known functions or the like may unnecessarily obscure the subject matter of the present invention, detailed descriptions of such known functions and the like will be omitted.

2 is a block diagram illustrating a matching circuit using a PI network according to the present invention.

A matching circuit using a PI network according to the present invention (hereinafter, referred to as a PI matching circuit) performs matching by replacing a λ / 4 transmission line.

As shown in FIG. 2, the PI matching circuit includes an inductor L _a and two high capacitance capacitors C _a , one end of which is grounded and the other end of which is connected in parallel with both ends of the inductor L _a . By using the PI matching circuit, matching can be performed with a size smaller than that of the λ / 4 transmission line that has been conventionally used for matching.

The capacitance value of the inductor L _a is obtained by Equation 1 below, and the capacitance value of the capacitor C _a is obtained by Equation 2 below.

The broadband power amplifier for WiBro / WiMAX having an internal PI matching circuit according to the present invention implements the above-described internal PI matching circuit by using a high capacitance capacitor and a thin wire welding inductor.

That is, by inserting a high dielectric constant dielectric substrate inside the amplifier package and stacking a metal pattern on the upper and lower surfaces of the dielectric, a high-capacitance capacitor can be miniaturized. In this case, it is preferable to use a high dielectric constant ceramic having a dielectric constant of 80 or more or a ferroelectric of several hundreds of dielectric constants.

The inductor is implemented in the form of a thin wire welding (Bond Wire) that can adjust the inductance value by changing any one of the length of the pad, the thickness of the wire, the height and the material of the pad.

3 is a block diagram in which a PI matching circuit according to the present invention is applied to a conventional power amplifier, and FIG. 4 is a block diagram of a power amplifier including the block diagram of FIG. 3 using a high capacitance capacitor.

The amplifier package consists of a power device such as GaN, a capacitor, an inductor, and a transmission line required for an input / output matching circuit.

As shown in FIG. 4, the present invention replaces the transmission line used for matching in the conventional amplifier, and applies the internal PI matching circuit using a high capacitance capacitor and a wire wire inductor to match the transmission line. To perform.

The capacitor implements the capacitor by inserting a dielectric substrate (eg, ceramic or polymer) into the package, and forming a conductive pattern (eg, a metal pattern) on the top and bottom surfaces of the dielectric. At this time, the size of the capacitor can be reduced by using a dielectric having a high dielectric constant. In other words, by applying a high-k dielectric ceramic having a dielectric constant of 80 or more, or by applying a ferroelectric material having a dielectric constant of several hundred or more, a small high capacity capacitor can be realized.

The inductor is implemented in the form of a thin wire welding, and the inductance value is adjusted according to the length between the pad, the thickness of the wire, the height, and the material.

In the present invention, the PI matching circuit is applied in two stages in the package instead of the two stage matching circuit (for example, a transmission line), which is conventionally implemented in each stage in and outside the package. That is, according to the present invention, by using a high capacitance capacitor and a thin wire welding inductor, two stage internal PI matching circuits can be applied in a package, thereby miniaturizing the amplifier.

In applying such a two-stage internal PI matching circuit, two capacitors connected in parallel to each other may be implemented by replacing one capacitor equivalent to the sum of the values of the two capacitors connected in parallel. That is, as shown in Figures 3 and 4, one having a value equivalent to the sum of the capacitance of the two capacitors in place of the two capacitors C _a and C _b connected in parallel to each other (C _a + C _b ) Can be replaced with a capacitor. In addition, the capacitor C _c and C _d may be replaced with one capacitor having a value of C _c + C _d .

FIG. 5 is a block diagram of a broadband power amplifier for WiBro / WiMAX including an LC resonant circuit for removing secondary harmonics according to the present invention. FIG. 6 is a schematic diagram showing an embodiment of the amplifier shown in FIG.

As shown in the drawing, by connecting the inductor L ₁ and the capacitor C ₁ in series, an LC resonant circuit capable of removing secondary harmonics can be configured. As shown in FIG. 6, the LC resonant circuit may be implemented with a high capacitance capacitor 212 and a wire inductor 211 formed on the dielectric substrate 210.

As another embodiment of the present invention, an amplifier including both the aforementioned two stage internal PI matching circuit and the aforementioned LC resonant circuit may be mentioned.

By using the inductor implemented in the form of a high capacitance capacitor and a thin wire welded by stacking a conductor pattern on a dielectric substrate inserted in a package as described above, a two stage PI matching circuit and an LC resonant circuit Can be configured in size. The small PI matching circuit and the LC resonant circuit may be provided inside the amplifier package. Therefore, the amplifier can be configured with various functions while keeping the size small.

FIG. 7 is a graph illustrating a change in a self inductance value according to the number of wires of an inductor.

At this time, the material of the bonding wire constituting the inductor (Metal) was applied to the gold, the diameter of the wire is 20 ㎛, the total length is 2.6 mm. As shown, as the number of wires increases, the inductance decreases and converges to a constant value.

In addition, although not shown in the simulation results according to the graph, the shunt capacitance from the inductor to the die pad increases with the number of wires. Therefore, it is desirable to determine the structure and interconnection of the package in consideration of these characteristics when implementing an internal matching circuit and an LC resonant circuit for removing second harmonics.

The embodiments of the present invention have been described above in detail based on the drawings. Those skilled in the art will be able to perform various modifications and equivalent other embodiments from the foregoing detailed description and drawings, and thus the true technical protection scope of the present invention is defined based on the following claims. It will be apparent to those skilled in the art that the scope of the present invention and equivalent embodiments thereof are included.

1 is a block diagram showing an equivalent circuit of a conventional broadband power amplifier.

2 is a block diagram showing a matching circuit using a PI network according to the present invention.

3 is a block diagram in which a PI matching circuit is applied to a conventional power amplifier.

4 is a configuration diagram of a power amplifier in which the block diagram of FIG. 3 described above is configured using a high capacity capacitor.

5 is a block diagram of an amplifier including an LC resonant circuit for canceling secondary harmonics in accordance with the present invention.

6 is a schematic diagram illustrating one embodiment of the amplifier shown in FIG. 5;

7 is a graph showing a change in magnetic inductance value according to the number of wires of an inductor.

Claims (9)

As a broadband power amplifier for WiBro / WiMAX, Power amplifier; And Including two internal PI matching circuit connected to each of the input and output terminals of the power amplifier, The internal PI matching circuit of each of the two stages is a series of two PI matching circuits composed of two high capacitance capacitors and an inductor located between the two high capacitance capacitors. And the power amplifier and the internal PI matching circuits of each of the two stages are provided in one package. The broadband power amplifier for WiBro / WiMAX having two stages of internal PI matching circuit using a high capacitance capacitor. The method of claim 1, The internal PI matching circuit of the second stage is composed of one capacitor that is equivalent to the sum of the two capacitor values by replacing two capacitors connected in parallel. Broadband power amplifier for WiBro / WiMAX with two stage PI matching circuit using high capacity capacitor. delete The method of claim 1, The high capacitance capacitor is implemented by stacking a metal pattern on the upper and lower surfaces of the dielectric substrate inserted into the package. Broadband power amplifier for WiBro / WiMAX with two stage PI matching circuit using high capacity capacitor. The method of claim 4, wherein the dielectric, Of high dielectric constant ceramic or ferroelectric with a dielectric constant of 80 or higher Broadband power amplifier for WiBro / WiMAX with two stage PI matching circuit using high capacity capacitor. The method of claim 1, wherein the inductor, Implemented in the form of thin wire welding, in which the inductance value can be adjusted by changing the length between the pad and the pad, the thickness of the wire, and the material. Broadband power amplifier for WiBro / WiMAX with two stage PI matching circuit using high capacity capacitor. As a broadband power amplifier for WiBro / WiMAX, Power amplifier; Two internal PI matching circuits connected to each of an input terminal and an output terminal of the power amplifier; And Including LC resonant circuit configured by connecting high capacitance capacitor and inductor, The internal PI matching circuit of each of the two stages is a series of two PI matching circuits composed of two high capacitance capacitors and an inductor located between the two high capacitance capacitors. Broadband for WiBro / WiMAX having a two stage internal PI matching circuit using a high capacitance capacitor, wherein the power amplifier, each of the two stage internal PI matching circuits and the LC resonant circuit are provided in one package. Power amplifier. The method of claim 7, wherein The high capacitance capacitor is implemented by stacking a metal pattern on the upper and lower surfaces of the dielectric substrate inserted into the package. Broadband power amplifier for WiBro / WiMAX with internal PI matching circuit and LC resonant circuit. The method of claim 7, wherein the inductor, Implemented in the form of thin wire welding, in which the inductance value can be adjusted by changing the length between the pad and the pad, the thickness of the wire, and the material. Broadband power amplifier for WiBro / WiMAX with internal PI matching circuit and LC resonant circuit.

Images