JP2003324326A - High-frequency amplifying unit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a high-frequency amplifier which has small mounting area of occupation on a substrate and has a high efficiency characteristic and further to obtain a high-frequency amplifier united module with an APC function including a control IC. <P>SOLUTION: The amplifier comprises a GaAs chip 2 where a transistor is formed, a block 4 of an output-side matching circuit and a coupler circuit for output distribution, and an APC-IC 3 which compares an output distributed from the block 4 with an output control signal 7 from a base band IC and supplies a control circuit to a bias circuit of a high-frequency amplifying circuit and the APC-IC 3 comprises a circuit 8 which detects and amplifies the output signal of the coupler, a circuit 9 which amplifies the control signal, a circuit 10 which compares them and supplies the control signal to the bias circuit, and a circuit 11 which applies a bias to the amplifier. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high frequency amplifier using a field effect transistor (FET) or a bipolar transistor.

[0002]

2. Description of the Related Art As a method of controlling the output power of a high-frequency amplifier for mobile phones (especially for European digital mobile phones) by using an external signal, a part of the output power is monitored by using a distribution circuit such as a coupler. However, there is a method of comparing the control signal with the monitor output and generating a signal corresponding to the difference to control the bias circuit of the high frequency amplifier to change the output power. That is, a loop is formed and controlled by the high frequency amplifier, the coupler, the control circuit, and the bias circuit.

In the prior art, a high frequency amplifier requires an amplifying element and a matching circuit and is constructed as a module in order to obtain characteristics of high output and high efficiency, and a control IC (APC-IC: Automatic Power) including an arithmetic circuit and the like.
Control IC) consists of another package,
The output circuit has been configured such that each component including the coupler is mounted on the printed circuit board of the mobile phone.

[0004]

In the above-mentioned conventional output circuit block configuration, since each component is formed separately and is configured on the set substrate including the peripheral circuits, as a result, the mounting area occupied by the output circuit section is reduced. It had the drawback of becoming very large.

In particular, the matching circuit for extracting the high frequency output is formed in the module of the amplifier, and the coupler that distributes the output to the detection circuit is mounted on the set substrate as a separate component, so that the set circuit is output until the output of the set. However, there is a problem that the efficiency is poor because high frequency loss occurs in both the matching circuit and the coupler, and the area occupied by both circuits on the set substrate is large.

An object of the present invention is to provide a high-frequency amplifier which is small and highly efficient.

[0007]

To achieve the above object, a high frequency amplifier according to the present invention comprises an integrated module in which a high frequency amplification element, a matching circuit and an output distribution circuit (coupler) are formed on the same substrate. Thus, a high-frequency amplifier having a small size, a small mounting area on a set substrate, and a high efficiency characteristic is obtained. Further, for miniaturization, a high frequency amplifier integrated module with an APC function including a control IC can be further used.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) FIG. 1 shows a circuit configuration of a high-frequency amplifier according to a first embodiment of the present invention. This amplifying apparatus is composed of a GaAs chip 2 formed with a field effect transistor or a bipolar transistor, a matching circuit on the output side, a block 4 of a coupler circuit for output distribution, and a coupler with a matching circuit formed for input and interstages. The high frequency amplifier module 1 is used.

In an actual mobile phone set, it is used in combination with the APC-IC 3 which compares the output distributed from the block 4 with the output control signal 7 from the baseband IC and gives a control signal to the bias circuit of the high frequency amplifier circuit. To be done. The APC-IC3 detects the output signal of the coupler.
It is composed of a circuit 8 for amplifying, a circuit 9 for amplifying a control signal, a circuit 10 for performing a comparison operation on them to give a control signal to a bias circuit, and a circuit 11 for giving a bias to an amplifier. The bias circuit may be formed on the module side of the high frequency amplifier.

FIG. 2 is a high frequency amplifier 1 with an integrated coupler of FIG.
It is a block diagram of. Here, an example of a two-stage bipolar transistor is shown.

Reference numeral 17 in FIG. 2 is a portion having a function of an output matching circuit and a coupler, and its circuit diagram is shown in FIG.

An output matching circuit 24 composed of a microstrip line 27 and a parallel capacitor is formed from the output 23 of the latter-stage amplifier element to the output 18 of the coupler-integrated high-frequency amplifier module, and a part of the output matching circuit 24 is further formed.
It has a structure forming a part of 5.

Conventionally, since the coupler circuit is formed outside the amplifier module, as shown in FIG. 4, the matching circuit 24, the coupler circuit 25, and the microstrip line 27a forming a part of the coupler circuit are separate circuits. Was becoming. That is, the matching circuit is formed in the amplifier module, and the coupler circuit is mounted as a separate component on the substrate of the mobile phone. In this case, the component mounting area is increased and the total length of the microstrip line is increased, resulting in a large loss of high-frequency signals, resulting in a reduction in the efficiency of the transmitter of the mobile phone.

On the other hand, in the coupler integrated amplifier of the present invention, since the coupler circuit is a part of the matching circuit, it is necessary to form an output circuit having a small circuit scale, that is, a short microstrip line length and low loss. Therefore, it is possible to realize a small and highly efficient transmission circuit.

FIG. 5 is a circuit configuration of a high frequency amplifier according to a second embodiment of the present invention. In this embodiment, the Si chip of the APC-IC is mounted on the dielectric substrate 28, and the GaAs chip 2 of the high frequency amplification element, the output matching circuit and the coupler section are formed on the same substrate and are modularized.

With this configuration, not only the area of the output matching circuit and the coupler section is reduced, but also the package of the Si chip is not required, so that the mounting area of the transmitter section of the mobile phone can be further reduced. Further, a high-frequency matching circuit is also required between the coupler output and the detection circuit 8, but the integrated module of the present invention allows adjustment of characteristics in advance within the module. That is, the functions of the high-frequency amplification / output control system including the APC-IC can be integrally designed and integrated as a module, and it is possible to provide a component of the transmitter having excellent characteristics and stable characteristics.

FIG. 6 is a block diagram of a conventional transmitter. However, since the high frequency amplifier module, the APC-IC circuit, and the coupler are configured as separate parts, not only the area occupied by the transmitter is large, but also It was difficult to design because it was necessary to design on the mobile phone set side, including variations in parts.

Further, in the first embodiment, an example of a two-stage amplifier is explained as shown in FIG. 2, but the same effect can be obtained even if the amplifier has one stage or three or more stages. Needless to say.

[0020]

As described above, by forming the high frequency amplifier of the present invention, a high frequency amplifier having a small size, high efficiency and stable characteristics which cannot be obtained by the conventional method of separately configuring each component is obtained. be able to.

[Brief description of drawings]

FIG. 1 is a block diagram (1) of a high frequency amplifier according to a first embodiment of the present invention.

FIG. 2 is a block diagram (2) of the high-frequency amplifier according to the first embodiment of the present invention.

FIG. 3 is an output matching circuit and coupler circuit diagram of the high-frequency amplifier according to the first embodiment of the present invention.

FIG. 4 is a diagram of an output matching circuit and a coupler circuit of a conventional high frequency amplifier.

FIG. 5 is a block diagram of an APC-IC integrated high frequency amplifier according to a second embodiment of the present invention.

FIG. 6 is a block diagram of a conventional APC-IC, a coupler, and a high-frequency amplifier.

[Explanation of symbols]

1 Coupler integrated high frequency amplifier 2 GaAs chip 3 APC-IC 4 output matching circuit + coupler 5 High frequency signal input 6 High frequency signal output 7 Output control signal 8 Detection and amplification circuit 9 Control signal amplifier circuit 10 arithmetic circuit 11 Bias circuit

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 5J067 AA04 CA36 CA92 FA16 HA09                       HA24 HA29 KA12 KA29 KA33                       KA55 KA66 KA68 KS18 LS12                       MA11 SA13 TA01                 5J100 JA01 LA00 QA01 SA01

Claims (4)

[Claims] 1. A semiconductor chip in which a transistor is formed, a matching circuit for outputting high frequency power from the semiconductor chip, and a distribution circuit for distributing a part of the high frequency power extracted by the matching circuit are the same. A high-frequency amplifier, which is configured on a ceramic or resin substrate of. 2. The high-frequency amplifier device according to claim 1, wherein a distribution circuit is formed in a part of the matching circuit. 3. A first semiconductor chip having a transistor formed therein, a matching circuit for outputting high frequency power from the transistor, and a distribution circuit for distributing a part of the high frequency output power extracted by the matching circuit. A control signal amplification circuit for amplifying an output control signal from the outside, a detection circuit for detecting a signal to which the high frequency output power of the transistor is distributed, a detection output amplification circuit for amplifying a detection output of the detection circuit, and the control signal An arithmetic circuit that compares and amplifies the amplified signals from the amplifier circuit and the detection output amplifier circuit, and outputs a signal according to the result, and a bias that applies a bias voltage or a bias current to the transistor based on the output from the arithmetic circuit. A second semiconductor chip on which a circuit is formed, the first semiconductor chip, the second semiconductor chip, and the A high frequency amplifying device, wherein a matching circuit and the distribution circuit are formed on the same ceramic or resin substrate. 4. The high frequency amplifier according to claim 3, wherein a distribution circuit is formed in a part of the matching circuit.