JPH08307305A - Transmitting/receiving circuit for communication radio equipment, semiconductor integrated circuit device and the communication radio equipment - Google Patents

Abstract

PURPOSE: To reduce the size of a communication radio equipment and to improve an isolation characteristic between the transmission and reception of the radio equipment. CONSTITUTION: A change-over switch 40 switches connection between on antenna 30 and a transmitting amplifier 10 or a receiving low noise amplifier 20. A 1st wiring of characteristic impedance 50Ωconnects the antenna 30 to the switch 40. A matching circuit 60A on the receiving side matches the input impedance of the amplifier 20 with the output impedance of the amplifier 10. A matching circuit 70A for the antenna 30 mutually matches the input impedance of the amplifier 20 which is matched with the output impedance of the amplifier 10, the output impedance of the amplifier 10 and the characteristic impedance of the 1st wire 51. The amplifier 10 is connected to the switch 40 through a 1st coupling capacitor 81A and the matching circuit 60A is connected to the switch 40 through a 2nd coupling circuit 82A.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmitter / receiver circuit suitable for a communication radio device that uses the same frequency as a transmission frequency and a reception frequency, a semiconductor integrated circuit device having the transmission / reception circuit, and a communication radio device. Regarding

[0002]

2. Description of the Related Art In recent years, communication wireless devices such as mobile phone wireless devices have been reduced in size, weight and price,
The number of its users is increasing rapidly. In the conventional communication method, a method of separating a transmission frequency and a reception frequency is adopted. By the way, in order to support more users, digitalization of communication wireless devices is in progress,
According to this digital communication wireless device, it is possible to perform transmission and reception with the same frequency by time-dividing transmission and reception, which conventionally required two frequencies per line.

Further, a transmission amplifier, a reception low-noise amplifier, and a changeover switch for switching between transmission and reception in a transmission / reception circuit of a digital communication radio device,
A gallium arsenide field effect transistor (hereinafter referred to as GaA) having low voltage operation, high efficiency, low noise characteristics and high isolation characteristics.
Called sFET. ) Is often used.

Recently, with the spread of portable wireless devices, the demand for smaller size and lighter weight is increasing, and a transmitter / receiver circuit including a power amplifier for transmission, a changeover switch, a low noise amplifier for reception, a matching circuit, etc. is directly used as a semiconductor. Attempts to make integrated circuits are also active.

An example of a conventional transmission / reception circuit will be described below with reference to the drawings.

FIG. 8 shows the structure of a transmission / reception circuit of a conventional digital radio communication device using FETs. In FIG. 8, 10 is a transmission amplifier, 20 is a low noise amplifier for reception, and 30 is a transmission and An antenna for reception, 40 is a changeover switch for switching connection between the transmission amplifier 10 and the antenna 30 and connection between the reception low noise amplifier 20 and the antenna 30, and 51 is a characteristic impedance for connecting the antenna 30 and the changeover switch 40. A first wiring of 50Ω, a second wiring 52 having a characteristic impedance of 50Ω connecting the transmission amplifier 10 and the changeover switch 40, and a reference numeral 53 having a characteristic impedance of 50Ω connecting the low noise amplifier for reception 20 and the changeover switch 40. Third wiring, 60B is a matching circuit on the receiving side for matching the input of the receiving low noise amplifier 20, and 70B is a transmitting circuit. The matching circuit on the transmitting side for matching the output of the width device 10, 81B is a first coupling capacitance that AC-couples the output of the transmitting amplifier 10 and the input of the matching circuit 70B on the transmitting side, and 82B is the receiving side. This is a second coupling capacitance that AC-couples the output of the matching circuit 60B and the input of the receiving low-noise amplifier 20.

Further, in FIG. 8, 12 is a front-stage FET which constitutes the transmission amplifier 10, and 14 is the transmission amplifier 10.
Of the latter stage, 15B is the power supply terminal of the transmission amplifier 10, and 16 and 18 are the front stage FET 12 and the rear stage FE.
Capacitance forming the matching circuit 13 for matching with T14, 1
Reference numeral 7 is an inductor constituting the matching circuit 13, 19A is an inductor connected between the gate terminal of the FET 14 at the rear stage and the bias voltage power supply Vg1, and 19B is the FET 12 at the front stage.
And each power supply terminal 15B of the subsequent FET 14 and the power supply voltage V
An inductor connected between dd1 and 24A is an inductor connected between the gate terminal of the low noise FET 22 of the receiving low noise amplifier 20 and the bias voltage Vg2, and 24B is a received wave output of the receiving low noise amplifier 20. Inductors 61, 62 connected between the terminal 23B and the power supply voltage Vdd2
Is an inductor constituting the matching circuit 60B on the receiving side, 7
Reference numerals 1 and 73 are capacitors forming the matching circuit 70B on the transmission side, and 7
Reference numeral 2 is an inductor that constitutes the matching circuit 70B on the transmitting side.

The operation of the transmission / reception circuit configured as described above will be described below.

First, the operation at the time of reception will be described.

At the time of reception, the bias voltage Vg2 is applied to the low noise FET 22 of the reception low noise amplifier 20 and the power supply voltage Vdd2 is applied to the reception wave output terminal 23B, so that the reception low noise amplifier 20 is required. The power supply voltage is supplied, and the weak received signal input from the antenna 30 is amplified. In this case, since the transmission amplifier 10 does not need to be operated, the power supply voltage is not applied to save the battery.

The received signal input from the antenna 30 is input to the antenna side input / output terminal 41B of the changeover switch 40 through the first wiring 51 having a characteristic impedance of 50Ω. At this time, inside the changeover switch 40, the first FET 43, which is the shunt FET on the transmission side, and the third FE, which is the through FET on the reception side, are controlled by the control voltage input from the switch control signal input terminal 42B.
For example, 0V is applied to T45 to turn it on, and -5V is applied to the second FET 44, which is a through FET on the transmission side, and the fourth FET 46, which is a shunt FET on the reception side, to turn it off. Has been done. Therefore, the reception signal input from the antenna side input / output terminal 41B is switched to the reception side through the third FET 45 in the ON state. The transmitter side is electrically disconnected from the antenna side because the second FET 44 is off.
It is short-circuited by the 1st FET43 of an ON state.

The reception signal that has passed through the third FET 45 in the ON state is received from the reception terminal 47 of the changeover switch 40 through the third wiring 53 having a characteristic impedance of 50Ω and the second coupling capacitor 82B, and the matching circuit on the reception side. 60B is input. The reception signal input to the matching circuit 60B on the reception side is impedance-matched by the two inductors 61 and 62, and then input to the input terminal 21 of the low noise amplifier for reception 20. The reception signal input to the reception low noise amplifier 20 is amplified by the low noise FET 22 and then output from the reception wave output terminal 23B.

Next, the operation during transmission will be described.

At the time of transmission, the F before the amplifier 10 for transmission is used.
The power supply voltage Vdd1 is applied to the ET 12 and the FET 14 in the subsequent stage, and the bias voltage Vg1 is applied to the FET 14 in the subsequent stage, so that the modulation signal input to the transmission amplifier 10 is power-amplified to a level that can be supplied to the antenna 30.
In this case, since the receiving low noise amplifier 20 does not need to be operated, the power supply voltage is not applied to save the battery.

The modulated transmission signal is transmitted wave input terminal 1
The input transmission signal is input to 1B, and the input transmission signal is the FET of the previous stage.
After the first-stage power amplification by 12, the signal is input to the subsequent-stage FET 14 via the matching circuit 13, and the latter-stage F
The ET 14 performs the second stage amplification up to the required power. The amplified transmission signal has a first coupling capacitance 81.
The second wiring 5 having a characteristic impedance of 50Ω is input to the matching circuit 70B on the transmitting side via B and converted into an impedance of 50Ω by the matching circuit 70B on the transmitting side.
It is input to the transmission side terminal 48 of the changeover switch 40 via 2. At this time, inside the changeover switch 40, the second FET 44 and the fourth FET 4 are driven by the control voltage input from the switch control signal input terminal 42B.
For example, 0 V is applied to 6 to turn it on, and the first FET 43 and the third FET 45 are, for example, −5.
V is applied and turned off, and the transmission signal input from the transmission-side terminal 48 is switched to the antenna side through the second FET 44 in the on-state. The transmission signal switched to the antenna side has the first characteristic impedance of 50Ω.
After being input to the antenna 30 through the wiring 51, the signal is output as a radio wave from the antenna 30.

[0016]

However, according to the above-mentioned conventional configuration, the transmitting amplifier 10 and the receiving low-noise amplifier 20 have the second and third characteristic impedances of 50Ω.
The transmission signal output from the transmission amplifier 10 and the reception signal input to the reception low-noise amplifier 20 are impedance-converted to 50Ω, respectively, because they are connected to the changeover switch 40 via the wirings 52 and 53. Need to Therefore, when the transmission amplifier 10, the reception low-noise amplifier 20, and the changeover switch 40 are integrated on one chip, the matching circuit 60B on the receiving side and the matching circuit 70B on the transmitting side must also be integrated on the chip. Therefore, the area occupied by passive elements such as integrated inductors becomes very large. For this reason, the chip area is significantly increased, and it is difficult to reduce the size and cost of the communication wireless device. It is desired to develop a transceiver circuit that realizes a compact and low-priced communication wireless device adapted to a new communication system, and a semiconductor integrated circuit device that integrates such a transceiver circuit.

Further, when the signal is switched by the changeover switch 40 with a low impedance, the voltage is lowered and the isolation between the transmission and the reception is improved, but conventionally, the signal is switched with the impedance of 50Ω as described above. Since this is done, there is a problem in that the isolation characteristic is poor and an FET having a good isolation characteristic must be used. The isolation means that when the changeover switch 40 is in a state of outputting the transmission signal from the transmission amplifier 10 to the antenna 30,
The ratio of the signal flowing correctly from the transmitting amplifier 10 to the antenna 30 and the signal flowing from the transmitting amplifier 10 to the receiving low-noise amplifier 20 and having good isolation means that the transmitting amplifier 10 receives the receiving low-noise. Amplifier 20
It means that there are few signals flowing to. However, in reality, there are some signals flowing from the transmission amplifier 10 to the reception low noise amplifier 20.

The present invention solves the above problems all at once.
An object of the present invention is to make it possible to reduce the size of a communication radio device and to improve the isolation characteristic between transmission and reception.

[0019]

In order to achieve the above-mentioned object, the invention of claims 1 to 5 has the output impedance of the transmission amplifier and the input impedance of the reception amplifier on the side opposite to the antenna with respect to the changeover switch. The characteristic impedance on the side opposite to the antenna is smaller than that on the changeover switch by only matching the characteristic impedance, and the matching between the characteristic impedance on the side opposite to the antenna than the changeover switch and the characteristic impedance of the wiring connecting the changeover switch and the antenna is switched. This is done by a matching circuit provided between the switch and the wiring.

Specifically, the means for solving the problems of the first aspect of the present invention is to provide a transmission / reception circuit of a communication wireless device, a transmission amplifier for amplifying and outputting an input transmission signal, and an amplification of an input reception signal. And a receiving amplifier for outputting and a transmission signal having an antenna side input / output terminal for outputting the transmission signal to the antenna through a wiring having a predetermined characteristic impedance and inputting the reception signal from the antenna through the wiring, The transmission signal output from the transmission amplifier is input without passing through a matching circuit, and the input transmission signal is output to the antenna side input / output terminal in the first connection state and the antenna side input / output terminal. A changeover switch for changing over to a second connection state for outputting the received signal to the reception amplifier; and a changeover switch connected between the changeover switch and the reception amplifier. The receiving side matching circuit that matches the input impedance of the receiving amplifier and the output impedance of the transmitting amplifier, and is connected between the wiring and the changeover switch, the characteristic impedance of the wiring and the transmission amplifier. The antenna side matching circuit for matching with the output impedance is provided.

With the above structure, the transmission signal output from the transmission amplifier is input to the changeover switch without passing through the matching circuit, while the reception signal output from the changeover switch is received via the receiving side matching circuit. Since it is input to the amplifier for output, the output impedance of the transmission amplifier and the input impedance of the reception amplifier match inside the changeover switch, and both the output impedance and the input impedance inside the changeover switch are small. .

Further, since the matching between the characteristic impedance of the wiring and the output impedance of the transmitting amplifier is achieved by the antenna matching circuit, the receiving side matching circuit has a function of matching the input impedance of the receiving amplifier with the output impedance of the transmitting amplifier. Just have to.

Further, since the antenna side matching circuit is connected between the wiring and the changeover switch, the transmitting amplifier,
When the receiving amplifier and the changeover switch are integrated into one chip, the antenna side matching circuit can be provided outside the chip.

According to a second aspect of the present invention, in the configuration of the first aspect, a first coupling capacitor connected between the transmission amplifier and the changeover switch, the changeover switch and the receiving side matching circuit are provided. A configuration in which a second coupling capacitor connected between them is provided is added.

With the above structure, since the transmission amplifier and the changeover switch are connected via the first coupling capacitor, the coupling state between the transmission amplifier and the changeover switch is stable, and the changeover switch and the reception side matching are stable. Since the circuit is connected via the second coupling capacitor, the coupling state between the changeover switch and the receiving side matching circuit is stable.

According to a third aspect of the present invention, the antenna side matching circuit is directly connected to the antenna side input / output terminal in addition to the configuration of the first aspect.

With the above configuration, the antenna side matching circuit can be mounted on the same chip as the transmitting amplifier, the receiving amplifier and the changeover switch.

According to a fourth aspect of the present invention, in addition to the configuration of the first aspect, the changeover switch has a transmission side through F connected in series.
ET and a transmission side shunt FET, and a reception side through FET and a reception side shunt FET connected in series,
The transmission amplifier has at least one amplification FET that amplifies the input transmission signal, and the amplification FET at the final stage of the transmission amplifier also serves as the transmission-side shunt FET of the changeover switch. The configuration is added.

With the above structure, the amplification FET at the final stage of the transmission amplifier is the transmission side shunt FE of the changeover switch.
Since it also serves as T, it is not necessary to provide a shunt FET on the transmission side of the changeover switch, so that the transmission / reception circuit of the communication radio can be simplified.

According to a fifth aspect of the present invention, there is provided a means for solving the problems, wherein a transmitting / receiving circuit of a communication radio device amplifies and outputs an input transmission signal by amplifying an input transmission signal. And a reception amplifier for outputting a transmission signal to an antenna through a wiring having a predetermined characteristic impedance and an input / output terminal on the antenna side for inputting a reception signal from the antenna through the wiring. A first connection state in which a transmission signal input from an amplifier is output to the antenna side input / output terminal and a reception signal input from the antenna side input / output terminal is output to the reception amplifier without passing through a matching circuit. A changeover switch for changing over to the connection state of No. 2 and an output impedance of the transmission amplifier, which is connected between the transmission amplifier and the changeover switch. An antenna connected between the transmission side matching circuit for matching the input impedance of the receiving amplifier and the wiring and the changeover switch, and for matching the characteristic impedance of the wiring and the input impedance of the receiving amplifier. And a side matching circuit.

With the above configuration, the transmission signal output from the transmission amplifier is input to the changeover switch via the transmission side matching circuit, while the reception signal output from the changeover switch is used for reception without passing through the matching circuit. Since it is input to the amplifier, the output impedance of the transmission amplifier and the input impedance of the reception amplifier match inside the changeover switch, and both the output impedance and the input impedance inside the changeover switch are small.

Further, since matching between the characteristic impedance of the wiring and the input impedance of the receiving amplifier is performed by the antenna side matching circuit, the transmitting side matching circuit matches the output impedance of the transmitting amplifier with the input impedance of the receiving amplifier. In addition to having only the function, the antenna side matching circuit is connected between the wiring and the changeover switch. Therefore, when the transmitting amplifier, the receiving amplifier and the changeover switch are integrated into one chip, the antenna side matching circuit is It can be provided outside the chip.

According to a sixth aspect of the present invention, the output impedance of the transmission amplifier and the input impedance of the reception amplifier are matched to the characteristic impedances optimal for the changeover switch.

Specifically, the means for solving the problems according to the invention of claim 6 is that a transmitting / receiving circuit of a communication radio device amplifies a transmission signal inputted and amplifies a transmission signal, and amplifies a reception signal inputted. And a receiving amplifier for outputting and a transmission signal having an antenna side input / output terminal for outputting the transmission signal to the antenna through a wiring having a predetermined characteristic impedance and inputting the reception signal from the antenna through the wiring, A first connection state in which a transmission signal input from the transmission amplifier is output to the antenna side input / output terminal, and a second connection state in which a reception signal input from the antenna side input / output terminal is output to the reception amplifier A change-over switch for changing over to a state and a switch connected between the transmitting amplifier and the change-over switch, and the output impedance of the transmitting amplifier and the change-over switch are connected. Is connected between the transmitting switch matching circuit and the changeover switch and the receiving amplifier, and the input impedance of the receiving amplifier and the optimum characteristic impedance for the changeover switch are matched. And a matching circuit on the antenna side that is connected between the wiring and the changeover switch and that matches the characteristic impedance of the wiring and the characteristic impedance most suitable for the changeover switch. It is what

With the above configuration, the transmission signal output from the transmission amplifier is input to the changeover switch via the transmission side matching circuit, while the reception signal output from the changeover switch is received via the reception side matching circuit. Since it is input to the amplifier for output, the output impedance of the transmission amplifier and the input impedance of the reception amplifier match inside the changeover switch, and both the output impedance and the input impedance inside the changeover switch are small. .

Further, the transmitting side matching circuit has only the function of matching the output impedance of the transmitting amplifier to the characteristic impedance most suitable for the changeover switch, and the receiving side matching circuit is suitable for the input impedance of the receiving amplifier for the changeover switch. It only needs to have the function of matching the characteristic impedance.

Since the antenna side matching circuit is connected between the wiring and the changeover switch, the transmitting amplifier,
When the receiving amplifier and the changeover switch are integrated into one chip, the antenna side matching circuit can be provided outside the chip.

According to a seventh aspect of the present invention, the transmission amplifier has at least one amplification FET, and the transmission side through FET and the transmission side shunt F in which the changeover switch is connected in series are provided.
In the case of having a receiving side through FET and a receiving side shunt FET connected in series with ET, the transmitting side shunt F of the changeover switch is added to the final stage amplification FET of the transmitting amplifier.
It also serves as an ET.

[0039] Specifically, the means for solving the problems according to the seventh aspect of the present invention is to input a transmission / reception circuit of a communication radio with a transmission amplifier having at least one amplification FET for amplifying an input transmission signal. A reception amplifier for amplifying and outputting the received signal, an antenna side input / output terminal for outputting the transmission signal to the antenna and inputting the reception signal from the antenna, a transmission side through FET and a transmission side connected in series Shunt FET and receiving side through F connected in series
A first connection state in which a transmission signal input from the transmission amplifier is output to the antenna side input / output terminal and a reception signal input from the antenna side input / output terminal. A switching switch for switching to a second connection state for outputting to the reception amplifier, and the amplification FET at the final stage of the transmission amplifier is
The configuration also serves as the transmission side shunt FET of the changeover switch.

With the above-mentioned structure, as in the structure of claim 4, since the amplification FET at the final stage of the transmission amplifier also serves as the transmission-side shunt FET of the changeover switch, the transmission-side shunt FET of the changeover switch is particularly used. No need to provide.

According to another aspect of the present invention, there is provided a semiconductor integrated circuit device comprising: a semiconductor substrate; and a transmission amplifier which is formed on the semiconductor substrate and amplifies and outputs an input transmission signal. Formed on the semiconductor substrate,
A reception amplifier that amplifies and outputs an input reception signal, a wiring formed on the semiconductor substrate and having a predetermined characteristic impedance of the transmission signal, and a characteristic impedance of the wiring and an output impedance of the transmission amplifier The transmitting amplifier has an antenna-side input / output terminal for outputting a received signal from the antenna through the wiring and the antenna-side matching circuit while outputting to the antenna through the antenna-side matching circuit. The transmission signal output from the input signal is input without passing through a matching circuit, and the first connection state in which the input transmission signal is output to the antenna side input / output terminal and the reception signal input from the antenna side input / output terminal are A changeover switch for changing over to a second connection state for outputting to the reception amplifier; and a changeover switch formed on the semiconductor substrate. And a receiving-side matching circuit that is connected between the receiving amplifier and the changeover switch and matches the input impedance of the receiving amplifier with the output impedance of the transmitting amplifier. Is.

With the above structure, one semiconductor substrate is
A transmitter amplifier, a receiver amplifier, of the transceiver circuit according to claim 1.
Since the changeover switch and the receiving side matching circuit are formed, the transmitting amplifier, the receiving amplifier of these transmitting and receiving circuits,
The changeover switch and the matching circuit on the receiving side can be surely integrated into one chip.

According to a ninth aspect of the present invention, the configuration in which the antenna side matching circuit is formed on the semiconductor substrate is added to the configuration of the eighth aspect.

With the above configuration, the transmitting amplifier, the receiving amplifier, the changeover switch, the receiving side matching circuit, and the antenna side matching circuit of the transmitting / receiving circuit can be integrated into one chip.

The invention of claim 10 is based on the structure of claim 8.
The changeover switch includes a transmission side through FET and a transmission side shunt FET connected in series, and a reception side through FET and a reception side shunt FET connected in series, and the transmission amplifier receives the input transmission At least one amplification FET for amplifying a signal is provided, and the amplification FET at the final stage of the transmission amplifier also serves as the transmission side shunt FET of the changeover switch.

With the above configuration, as in the configuration of claim 4, since the amplification FET at the final stage of the transmission amplifier also serves as the transmission side shunt FET of the changeover switch, the transmission side shunt FET of the changeover switch is particularly used. No need to provide.

The means for solving the problems of the eleventh aspect of the present invention is to provide a semiconductor integrated circuit device, a semiconductor substrate, and at least one amplification FET which is formed on the semiconductor substrate and amplifies an input transmission signal. An amplifier for transmission having, an antenna side input / output terminal formed on the semiconductor substrate for outputting a transmission signal to an antenna and inputting a reception signal from the antenna, a transmission side through FET connected in series, and A first connection state having a transmission side shunt FET, a reception side through FET and a reception side shunt FET connected in series, and outputting a transmission signal input from the transmission amplifier to the antenna side input / output terminal. And a changeover switch for changing over to a second connection state in which the reception signal input from the antenna side input / output terminal is output to the reception amplifier. , The amplifier FET at the last stage of the transmitter amplifier, the transmission-side shunt FE of the changeover switch
The configuration also serves as T.

According to the above configuration, as in the case of the fourth aspect, since the amplification FET at the final stage of the transmission amplifier also serves as the transmission side shunt FET of the changeover switch, the transmission side shunt FET of the changeover switch is particularly used. No need to provide.

According to a twelfth aspect of the present invention, a means for solving the problems is to amplify a radio communication device, an antenna, a wiring having a predetermined characteristic impedance connected to the antenna, and amplifies and outputs an input transmission signal. A transmission amplifier, a reception amplifier that amplifies and outputs an input reception signal, and a transmission signal that outputs a transmission signal to the antenna through the wiring and inputs a reception signal from the antenna through the wiring. A first connection having an input / output terminal on the antenna side, the transmission signal output from the transmission amplifier is input without passing through a matching circuit, and the input transmission signal is output to the input / output terminal on the antenna side. A changeover switch for switching between a state and a second connection state in which a reception signal input from the antenna side input / output terminal is output to the reception amplifier; Connected between the wiring and the changeover switch, and a receiving side matching circuit that is connected between the width device and the changeover switch and that matches the input impedance of the reception amplifier with the output impedance of the transmission amplifier. In addition, the antenna side matching circuit that matches the characteristic impedance of the wiring and the input impedance of the transmission amplifier is provided.

According to a thirteenth aspect of the present invention, a wireless communication device includes a radio communication device, an antenna, a wiring having a predetermined characteristic impedance connected to the antenna, and amplifies and outputs an input transmission signal. A transmission amplifier, a reception amplifier that amplifies and outputs an input reception signal, and a transmission signal that outputs a transmission signal to the antenna through the wiring and inputs a reception signal from the antenna through the wiring. A first connection state that has an antenna side input / output terminal and outputs a transmission signal input from the transmission amplifier to the antenna side input / output terminal and a reception signal input from the antenna side input / output terminal. A changeover switch for changing over to a second connection state for outputting to the reception amplifier without passing through a matching circuit; and a transmission amplifier and the changeover switch. Connected to the transmission side matching circuit for matching the output impedance of the transmission amplifier and the input impedance of the reception amplifier, and connected between the wiring and the changeover switch, and the characteristic impedance of the wiring and The antenna side matching circuit that matches the input impedance of the receiving amplifier is provided.

According to a fourteenth aspect of the present invention, there is provided a solving means for a wireless communication device, an antenna, a wire having a predetermined characteristic impedance connected to the antenna, and amplifies and outputs an input transmission signal. A transmission amplifier, a reception amplifier that amplifies and outputs an input reception signal, and a transmission signal that outputs a transmission signal to the antenna through the wiring and inputs a reception signal from the antenna through the wiring. A first connection state that has an antenna side input / output terminal and outputs the transmission signal input from the transmission amplifier to the antenna side input / output terminal and the reception signal input from the antenna side input / output terminal Second output to the amplifier for
A changeover switch for changing over to the connection state of, and a connection between the transmission amplifier and the changeover switch,
A transmission side matching circuit for matching the output impedance of the transmission amplifier and the characteristic impedance most suitable for the changeover switch, and the input impedance of the reception amplifier connected between the changeover switch and the reception amplifier. A matching circuit on the receiving side for matching with the characteristic impedance most suitable for the changeover switch, and between the wiring and the changeover switch, is connected between the characteristic impedance of the wiring and the most suitable characteristic impedance for the changeover switch. The antenna side matching circuit is provided.

[0052]

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

(First Embodiment) FIG. 1A shows a schematic structure of a transmission / reception circuit of a conventional communication wireless device, and FIG. 1B shows a transmission / reception circuit of a communication wireless device according to the first embodiment. The schematic structure is shown.

In the configuration of FIG. 1A, as described in the section of the prior art, the characteristics of the antenna, the changeover switch, the transmission amplifier and the changeover switch, and the reception low noise amplifier and the changeover switch are shown. Impedance 5
Since they are connected by wiring of 0Ω, matching circuits are respectively interposed between the transmission amplifier and the wiring of characteristic impedance 50Ω, and between the receiving low noise amplifier and the wiring of characteristic impedance 50Ω.

On the other hand, in the configuration of FIG. 1B, the antenna and the changeover switch are connected by a wiring having a characteristic impedance of 50Ω, but the transmitting amplifier, the changeover switch, and the receiving low noise amplifier are connected. And the changeover switch are not connected by a wiring having a characteristic impedance of 50Ω. Also, a receiving side matching circuit is interposed between the receiving low noise amplifier and the changeover switch,
There is no matching circuit between the transmitting amplifier and the changeover switch. In the configuration of FIG. 1B, impedance matching between the transmission amplifier and the wiring having the characteristic impedance of 50Ω is achieved by the matching circuit on the antenna side provided between the wiring having the characteristic impedance of 50Ω and the changeover switch. The impedance matching between the transmitting amplifier and the receiving low noise amplifier is performed by the matching circuit on the receiving side.

The specific configuration of the transmission / reception circuit of the communication wireless device according to the first embodiment will be described below with reference to FIG.

In FIG. 2, reference numeral 10 denotes a transmission amplifier, and 20
Is a low noise amplifier for reception, 30 is an antenna for transmission and reception, 40 is a changeover switch for switching the connection between the transmission amplifier 10 and the antenna 30, and the connection between the low noise amplifier for reception 20 and the antenna 30, and 51 is Characteristic impedance 50 connecting the antenna 30 and the changeover switch 40
Ω first wiring, 60A is a receiving side matching circuit that matches the input impedance of the receiving low noise amplifier 20 with the output impedance of the transmitting amplifier 10, and 70A is the output of the transmitting amplifier 10 by the receiving side matching circuit 60A. The matching circuit on the antenna side for matching the input impedance of the receiving low-noise amplifier 20 and the output impedance of the transmitting amplifier 10 matched to the impedance with the characteristic impedance 50Ω of the first wiring 51, 81A is the transmitting amplifier 10 Is coupled to the input of the changeover switch 40 directly, and 82A is a matching circuit 60 on the receiving side.
This is a second coupling capacitance that directly couples A and the changeover switch 30. In FIG. 2, reference numeral 13 denotes a matching circuit for matching the FET 12 at the front stage and the FET 14 at the rear stage, and the matching circuit 13 is not directly related to the point of the present invention.

The transmitting amplifier 10, the receiving low noise amplifier 20, the changeover switch 40 and the receiving side matching circuit 60A described above are respectively formed on one semiconductor substrate 1.

Further, in FIG. 2, reference numeral 12 is a front-stage FET which constitutes the transmission amplifier 10, and 14 is the transmission amplifier 10.
FETs in the latter stage, 15A are power supply terminals of the transmission / reception integrated circuit 1, and 16 and 18 are FETs 12 in the front stage and FEs in the rear stage.
Capacitance forming the matching circuit 13 for matching with T14, 1
Reference numeral 7 is an inductor constituting the matching circuit 13, 19A is an inductor connected between the gate terminal of the FET 14 in the subsequent stage and the bias voltage Vg1, 19B is an inductor connected between the power supply terminal 15A and the power supply voltage Vdd1, and 23A. Is a received wave output terminal of the transmission / reception integrated circuit 1, 24A is an inductor connected between the gate terminal of the low noise FET 22 of the receiving low noise amplifier 20 and the bias voltage Vg2, and 24B is a received wave output terminal 23A and power supply voltage Vdd2. Inductors 71 and 73 connected between the antenna and the matching circuit 70 on the antenna side.
A is a capacitance constituting A, 72 is a matching circuit 70A on the antenna side
Is an inductor that constitutes the.

The operation of the transmission / reception circuit of the communication wireless device configured as described above will be described below with reference to FIGS. 2 and 3.

FIG. 3 shows the output matching state of the transmitting amplifier 10 and the input matching state of the receiving low noise amplifier 20 represented by the Smith diagram, and shows the receiving low noise amplifier 20 using a normal GaAs FET. The input impedance is in the vicinity of point A, and the output impedance of the transmission amplifier 10 is in the vicinity of point B (17-j8.8) Ω.

In the conventional transmission / reception circuit, as described with reference to FIG. 8, the input to the reception low noise amplifier 20 is matched with the impedance of 50Ω by the matching circuit 60B on the reception side, and the transmission amplifier 10 receives the impedance. The output was matched to the impedance of 50Ω by the matching circuit 70B on the transmission side. That is, the impedance of the receiving low noise amplifier 20 at the point A is adjusted to the point C by the matching circuit 60B on the receiving side, and the impedance of the transmitting amplifier 10 at the point B is adjusted to the point C by the matching circuit 70B on the transmitting side. Was there. This is because the input impedance of the receiving low noise amplifier 20 and the output impedance of the transmitting amplifier 10 are matched with the impedance of the wiring having the characteristic impedance of 50Ω.

However, in the first embodiment, the input impedance of the receiving low noise amplifier 20 is matched with the output impedance (point B) of the transmitting amplifier 10 by the matching circuit 60A on the receiving side. The resistance at point B is
(17-j8.8) Ω, which is significantly smaller than the characteristic impedance of the first wiring 51, which is 50Ω.

The output impedance of the transmission amplifier 10 at the point B and the input impedance of the reception low noise amplifier 20 are matched with the characteristic impedance (50Ω) of the first wiring by the matching circuit 70A on the antenna side. That is, the arrow from the point A to the point B represents the matching by the matching circuit 60A on the receiving side, and the arrow from the point B to the point C (50Ω) represents the matching by the matching circuit 70A on the antenna side. The point of the first embodiment is that the input impedance of the receiving low-noise amplifier 20 that is adjusted to the point B and the output impedance of the transmission amplifier 10 that is at the point B are both adjusted to the point C by the matching circuit 70A on the antenna side. Is.

Next, the operation at the time of reception will be described.

The received signal input from the antenna 30 is
After passing through the first wiring 51 having a characteristic impedance of 50Ω, the impedance is converted by the matching circuit 70A on the antenna side and input to the antenna side input / output terminal 41A. At this time, inside the changeover switch 40,
As described in the section of the prior art, the control signal input from the switch control signal input terminal 42A causes the first FET 43, which is the shunt FET on the transmission side, and the third FET 45, which is the through FET on the reception side, to operate. The second FET 44 that is turned on and is a through FET on the transmission side
And the fourth FET 45, which is the shunt FET on the receiving side, is turned off. Therefore, the antenna side input / output terminal 41
The received signal input from A is the third FET4 in the ON state.
It is switched to the receiving side through 5. Also, the sender is
Since the second FET 44 is in the off state, it is electrically separated from the antenna side, and the first FET 43 in the on state is electrically disconnected.
Shorted by.

The received signal that has passed through the third FET 45 in the ON state is input to the matching circuit 60A on the receiving side via the second coupling capacitor 82A. The reception signal input to the matching circuit 60A on the reception side is impedance-matched by the two inductors 61 and 62, and then amplified by the low noise FET 22 of the reception low noise amplifier 20,
It is output from the reception wave output terminal 23A.

Next, the operation during transmission will be described.

The modulated transmission wave is transmitted wave input terminal 11
Input to A. The input transmission signal is the previous FET
After the first-stage power amplification by 12, the signal is input to the subsequent-stage FET 14 via the matching circuit 13, and the latter-stage F
The ET 14 performs the second stage amplification on the required power. The amplified transmission signal is directly input to the second FET 44 of the changeover switch 40 via the first coupling capacitor 81A. At this time, an operation opposite to that at the time of reception is performed inside the changeover switch 40, and the second FET 44 and the fourth FET 46 are turned on by the control signal input from the switch control signal input terminal 42A, and The first FET 43 and the third FET 33 are turned off, and the transmission signal input through the first coupling capacitor 81A is switched to the antenna side through the second FET 44 in the on state. At this time, the receiving side has the third FET 4
Since 5 is in the off state, it is electrically disconnected from the transmitting side, and is short-circuited by the fourth FET 46 in the on state. Then, the transmission signal switched to the antenna side is input to the antenna side matching circuit 70A, and the characteristic impedance 50 is input by the antenna side matching circuit 70A.
After being impedance-converted to Ω, it is input to the antenna 30 through the first wiring 51 and is output as a radio wave from the antenna 30.

As described above, according to the first embodiment, the matching circuit 60A on the receiving side matches the input impedance of the receiving low-noise amplifier 20 with the output impedance of the transmitting amplifier 10 to switch to the transmitting amplifier 10. Since the matching circuit with the switch 40 is not required and the transmission amplifier 10 and the changeover switch 40 can be directly connected, the characteristic impedance of the changeover switch 40 can be lowered below 50Ω. As a result, the characteristic impedance of the changeover switch 40 side can be made smaller than 50Ω than that of the matching circuit 70A on the antenna side. Therefore, when the changeover switch 40 is switched to connect the transmission amplifier 10 and the antenna 30, The number of signals leaking from the credit amplifier 10 to the receiving low noise amplifier 20 is reduced, and the isolation characteristic is improved. Also, the changeover switch 40
Thus, when the receiving low noise amplifier 20 and the antenna 30 are connected, the number of signals leaking from the receiving low noise amplifier 20 to the transmitting amplifier 10 is reduced.

Further, since the matching circuit 70A on the antenna side can be arranged closer to the antenna 30 than the input / output terminal 41A on the antenna side, the matching circuit 70A on the antenna side can be arranged.
Can be taken out of the transmission / reception integrated circuit 1, the area of the integrated chip can be reduced, and the transmission / reception circuit can be downsized and the cost can be reduced.

Further, since the matching circuit 70A on the antenna side is commonly used for both transmission and reception, the size of the matching circuit 60A on the reception side can be reduced, so that the size and cost of the chip can be reduced. Can be further improved.

Instead of the first embodiment, the antenna matching circuit 70A may be provided integrally with the transmission / reception integrated circuit 1.

(Second Embodiment) A semiconductor integrated circuit device according to a second embodiment of the present invention will be described below with reference to the drawings. The semiconductor integrated circuit device according to the second embodiment realizes the transceiver circuit of the communication wireless device according to the first embodiment, and its operation is the same as that of the first embodiment.

FIG. 3 shows a layout of the semiconductor integrated circuit device according to the second embodiment. In addition, in FIG.
The same components as those of the transmission / reception circuit of the first embodiment shown in FIG. 2 are designated by the same reference numerals and the description thereof will be omitted. The FET 12 in the front stage of the transmission amplifier 10 is composed of a drain, a gate, a source, a gate, and a drain, which are sequentially illustrated from the left side.

In FIG. 3, 101 is a ground terminal pad, 102 is a power supply terminal 15A pad, 103 is an antenna side input / output terminal 41A pad, and 104 is a switch control input connected to the third FET 45 of the changeover switch 40. The pad of the terminal 42A, 105 is the ground terminal and the pad of the source terminal of the FET 12 in the preceding stage of the transmission amplifier 10, and 106 is the transmission wave input terminal 11A and the transmission amplifier 1.
0 is the gate terminal pad of the FET 12 in the previous stage, 107 is the gate terminal pad of the second FET 44 of the changeover switch 40, and 108 is the first FET 4 of the changeover switch 40.
The pad of the switch control input terminal 42A connected to 3,
109 is a pad of a switch control input terminal 42A connected to the fourth FET 46 of the changeover switch 40, 110 is a pad of a ground terminal, and 111 is a received wave output terminal 23A.
Pad of.

As described above, when all the elements constituting the transmission / reception circuit are integrated on one chip, by adopting the circuit configuration of the first embodiment, the antenna side which has conventionally had to be integrated on the chip side. The matching circuit 70A can be arranged outside the chip.

Further, by sharing the matching circuit 70A on the antenna side both during transmission and during reception, the size of the inductors 61 and 62 forming the matching circuit 60B on the receiving side can be reduced, so that the semiconductor It is possible to reduce the size and cost of the integrated circuit device.

In the first embodiment, the transmission amplifier 10, the reception low noise amplifier 20 and the changeover switch 4 are used.
In 0, a GaAsFET was used, but instead of this, a silicon MOSFET may be used.

(Third Embodiment) A transmitting / receiving circuit of a communication radio device according to a third embodiment of the present invention will be described below with reference to the drawings.

FIG. 5A shows a schematic configuration of a transmission / reception circuit of a communication radio device according to the third embodiment. In the third embodiment, unlike the first embodiment, a transmission amplifier and a switching amplifier are switched. While the matching circuit on the transmission side is provided between the switch and the switch, the matching circuit is not provided between the low noise amplifier for reception and the changeover switch.

In order to adopt such a structure, a silicon bipolar transistor is used for the receiving low noise amplifier, while a GaAs FET is used for the transmitting amplifier, and the input impedance of the silicon bipolar transistor is the input of the GaAs FET. Must be lower than impedance. Then, in this case, it is necessary to lower the input impedance of the transmission amplifier by the matching circuit on the transmission side and match it with the output impedance of the reception low noise amplifier.

(Fourth Embodiment) A transmission / reception circuit of a communication radio device according to a fourth embodiment of the present invention will be described below with reference to the drawings.

FIG. 5B shows a schematic configuration of a transmission / reception circuit of a communication radio device according to the fourth embodiment. In the fourth embodiment, a transmission side is provided between a transmission amplifier and a changeover switch. Is provided, and the receiving side matching circuit is provided between the receiving low noise amplifier and the changeover switch. At first glance, this configuration is similar to the conventional transmission / reception circuit, but differs in the following points. That is, in the fourth embodiment, the characteristic impedance on the antenna side of the matching circuit on the antenna side is 50Ω, and the characteristic impedance on the changeover switch side of the matching circuit on the antenna side is set to an optimum value for the changeover switch. Has been done.

As described above, in the fourth embodiment, the impedance of the changeover switch side is set to the optimum impedance for the changeover switch rather than the matching circuit on the antenna side, and the transmission amplifier and the changeover switch are set in order to match the optimum impedance. The matching circuit on the transmitting side is provided between the receiving circuit and the matching circuit on the receiving side between the low noise amplifier for reception and the changeover switch.

The significance of setting the impedance of the changeover switch side to the optimum impedance of the changeover switch rather than the matching circuit on the antenna side will be described below with reference to FIG.

In FIG. 6, 10 is a transmission amplifier, and 20
Is a low noise amplifier for reception, 30 is an antenna for transmission and reception, 40 is a changeover switch, 51 is a characteristic impedance of 50Ω for connecting the antenna 30 and the changeover switch 40.
, 60C is a matching circuit on the transmission side for matching the output impedance of the transmission amplifier 10 and the characteristic impedance most suitable for the changeover switch 40, and 60D is the input impedance of the reception low noise amplifier 20 and the changeover switch 40. 81A is a matching circuit on the receiving side for matching with the optimum characteristic impedance on the receiving side, and 70A is a matching circuit on the antenna side for matching the optimum characteristic impedance for the changeover switch 40 with the characteristic impedance of 50Ω of the first wiring 51, 81A.
Is a first coupling capacitance that couples the matching circuit 60C on the transmitting side with the changeover switch 40, and 82A is a low noise amplifier for reception 2
This is a second coupling capacitance that couples 0 with the changeover switch 30.

First, when the change-over switch 30 connects the transmission amplifier 10 and the antenna 30, the insertion loss of the second FET 44, which is the through FET on the transmission side, will be examined.

If the insertion loss of the second FET 44 is L, then L = 10 × log ((2Z0 + Ron) / 2 × Z0) ² dB (1) where Z0 is the wiring in which the second FET 44 is inserted. A characteristic impedance 54 of the second FET 44 is an ON resistance of the second FET 44.

In the conventional structure, the characteristic impedance Z0 of the wiring 54 is 50Ω, which is the same as the characteristic impedance of the first wiring 51. Therefore, L = 10 × log ((1
00 + Ron) / 100) ² dB, and the insertion loss: L is determined by the characteristic (Ron) of the second FET.

However, in the fourth embodiment, since the matching circuit 60C on the transmission side is provided, the characteristic impedance of the wiring 44 can be set to the optimal characteristic impedance for the changeover switch 40. Specifically, Z
By increasing 0, (2Z0 + Ron) / 2 x Z
0) ² can be reduced to reduce the insertion loss L of the second FET.

If the insertion loss L of the second FET is fixed, the gate width of the second FET 44 can be reduced. That is, in the equation (1), Z0 = 50
The on resistance when Ω is Ron1, the on resistance when Z0 = 100Ω is Ron2, and the insertion loss of the second FET is:
If L is constant, L = 10 × log ((2 × 50
+ Ron1) / 2 × 50) ² = 10 × log ((2 × 100
+ Ron2) / 2 × 100) ² , so Ron2 = 2 ×
It becomes Ron1.

Since the on-resistance: Ron of the FET is inversely proportional to the gate width Wg, when the on-resistance: Ron doubles, the gate width: Wg becomes 1/2. That is, in the transmission / reception circuit, the changeover switch 40 has the largest area. Therefore, the area of the changeover switch 40 can be reduced by optimizing the characteristic impedance of the changeover switch 40 and reducing the second FET 44 of the changeover switch 40. Therefore, the matching circuit 60C on the transmitting side and the matching circuit 6 on the receiving side
Even if the area of 0D is slightly increased, the area of the changeover switch 40 can be further reduced, so that the entire area of the transmission / reception circuit is reduced and the transmission / reception circuit can be downsized.

Further, for the same reason as above, if the gate width Wg of the second FET 44 is made constant, the insertion loss L of the second FET 44 can be halved.

As described above, the changeover switch 40
By optimizing the characteristic impedance of the second FET, the insertion loss of the second FET can be reduced, and the insertion loss of the second FET can be made constant to reduce the gate width of the second FET and thus the area of the second FET. It becomes possible to do.

(Fifth Embodiment) A transmission / reception circuit of a communication radio device according to a fifth embodiment of the present invention will be described below with reference to FIG.

In FIG. 7, 10 is a transmission amplifier, and 20
Is a low noise amplifier for reception, 30 is an antenna for transmission and reception, 40 is a changeover switch for switching the connection between the transmission amplifier 10 and the antenna 30, and the connection between the low noise amplifier for reception 20 and the antenna 30, and 60A is The receiving side matching circuit that matches the input impedance of the receiving low noise amplifier 20 to the same value as the output impedance of the transmitting amplifier 10, 70A is matched to the same value as the output impedance of the transmitting amplifier 10 by the receiving side matching circuit 60A. The matching circuit on the antenna side for matching the input impedance of the received low-noise amplifier 20 and the output impedance of the transmission amplifier 10 with the characteristic impedance 50Ω of the wiring connected to the antenna 30, 81A is a transmission amplifier. 1
A first coupling capacitance that directly couples the output of 0 and the input of the changeover switch 40, 82A of the receiving low-noise amplifier 20 having the same value as the output impedance of the transmitting amplifier 10 by the matching circuit 60A on the receiving side. It is a second coupling capacitance that directly couples the input and the output of the changeover switch 30.

The transmission amplifier 10 and the changeover switch 40 described above are formed on one semiconductor substrate 1.

A feature of the fifth embodiment is that the change-over switch 30 includes a FET 14 at the rear stage of the transmission amplifier 10 functioning as a transmission side shunt FET and a transmission side through FET.
Second FET 44 that functions as a receiving side through FE
It is composed of a third FET 45 functioning as T and a fourth FET 46 functioning as a receiving side shunt FET.

First, the operation during transmission will be described.

At the time of transmission, the F of the preceding stage of the transmission amplifier 10 is used.
Bias voltages Vg1 and Vg2 are applied to the gate terminals of the ET 12 and the FET 14 of the subsequent stage, respectively, and the F of the previous stage is applied.
The power supply voltage Vdd is applied to the source terminals of the ET 12 and the FET 14 in the subsequent stage, and the modulation signal input to the transmission amplifier 10 is power-amplified to a level that can be supplied to the antenna 30. Further, in the changeover switch 40, the control voltage V is set so that the transmitting side is turned on and the receiving side is turned off.
c1 and Vc2 are applied. For example, 0V is applied as the control voltage Vc1 to the gate terminals of the second FET 44 and the fourth FET 46, and -5V is applied as the control voltage Vc2 to the gate terminal of the third FET 45. At this time, since the receiving low noise amplifier 20 does not need to be operated, the power supply voltage is not applied to the receiving low noise amplifier 20.

Next, the operation at the time of reception will be described.

At the time of reception, the required power supply voltage is applied to the reception low noise amplifier 20, and the antenna 30 is connected to the matching circuit 70A on the antenna side, the changeover switch 40, the second coupling capacitor 82A and the matching circuit 60A on the reception side. The weak reception signal input to the low noise amplifier for reception 20 via this is ready to be amplified. At this time, the high-frequency signal input to the receiving low-noise amplifier 20 has a matching circuit 70A on the antenna side and a matching circuit 60A on the receiving side as described in the first embodiment.
Needless to say, the impedance is matched by. Further, in the changeover switch 40, the control voltage V is set so that the transmitting side is turned off and the receiving side is turned on.
c1, Vc2 and Vg2 are applied. For example, the second FET
The control voltage Vc1 of the FET 44 and the fourth FET 46 is -5.
V is applied, and 0 V is applied to the third FET 45 as a control voltage Vc2.

Further, 0V is applied to the FET 14 at the subsequent stage of the transmission amplifier 10 which functions as the transmission side shunt FET. At the time of reception, the power amplifier voltage is not applied to the transmission amplifier 10 in order to save the battery.
Since the drain current does not flow even if 14 is turned on with respect to the ground, it is possible to ground with respect to high frequencies.
In this way, the FET 14 at the rear stage of the transmission amplifier 10
Can play the role of the transmission side shunt FET of the changeover switch 40. That is, the FET 14 at the subsequent stage of the transmission amplifier 10 is configured so that the transmission amplifier 1 is used during transmission.
A bias voltage Vg2 of, for example, -5V is applied to the gate terminal to function as the FET of the final stage of 0, and a bias Vg2 of 0V, for example, is applied to the gate terminal to function as the transmission side shunt FET of the changeover switch 40 during reception. It will be.

As described above, according to the fifth embodiment, not only can the structure of the transmission / reception circuit of the communication wireless device be simplified, but when the transmission / reception circuit is formed into a semiconductor integrated circuit, the number of parts can be reduced and communication can be reduced. It is possible to contribute to downsizing of a wireless device for a mobile phone, reduction in area of a semiconductor integrated circuit, no adjustment of a high frequency section, and eventually cost reduction.

[0106]

According to the transmission / reception circuit of the communication radio device of the present invention, the transmission signal output from the transmission amplifier is input to the changeover switch without passing through the matching circuit, and is output from the changeover switch. Since the received signal is input to the receiving amplifier via the receiving side matching circuit,
The output impedance of the transmission amplifier and the input impedance of the reception amplifier inside the changeover switch are small, and the area of the changeover switch can be made small, and the reception side matching circuit matches the input impedance of the reception amplifier with the output impedance of the transmission amplifier. Since the area of the receiving side matching circuit can be reduced, it is possible to reduce the size and cost of the chip having the transmitting amplifier, the receiving amplifier and the changeover switch, and hence the communication wireless device including the chip. Can be planned.

Further, as described above, since the output impedance of the transmission amplifier and the input impedance of the reception amplifier inside the changeover switch can be made small,
It is possible to improve the isolation characteristic of the changeover switch.

Further, since the antenna side matching circuit for matching the characteristic impedance of the wiring and the output impedance of the transmission amplifier is connected between the wiring and the changeover switch, the transmission amplifier, the reception amplifier and the changeover switch are connected. In the case of integrating the chip into a single chip, the antenna side matching circuit can be provided outside the chip, so that the chip and the communication device radio equipped with the chip can be further downsized and reduced in cost.

According to the transmitting / receiving circuit of the communication radio device of the invention of claim 2, since the transmitting amplifier and the changeover switch are connected via the first coupling capacitor, the coupling state of the transmitting amplifier and the changeover switch is Further, since the changeover switch and the receiving side matching circuit are connected via the second coupling capacitor, the coupling state between the changeover switch and the receiving side matching circuit can be stabilized.

According to the transmitter / receiver circuit of the communication radio device of the invention of claim 3, since the antenna side matching circuit is directly connected to the antenna side input / output terminal of the changeover switch, the antenna side matching circuit is connected to the transmitting amplifier and the receiving side. Since the amplifier and the changeover switch can be mounted on the same chip, the wireless communication device can be further downsized.

According to the transmitting / receiving circuit of the communication radio device of the invention of claim 4, the transmitting side shunt FE of the changeover switch is
Since it is not necessary to provide T in particular, the transmitting / receiving circuit of the communication radio becomes simple. For this reason, the number of parts is reduced, so that the miniaturization of the communication wireless device is promoted and the reliability is improved.

According to the transmitter / receiver circuit of the radio device for communication equipment according to the fifth aspect of the invention, the transmission signal output from the transmission amplifier is input to the changeover switch via the matching circuit on the transmission side and is output from the changeover switch. Since the received signal is input to the receiving amplifier without passing through the matching circuit,
The output impedance of the transmission amplifier and the input impedance of the reception amplifier inside the changeover switch are small, and the area of the changeover switch can be reduced, and the transmission side matching circuit matches the output impedance of the transmission amplifier with the input impedance of the reception amplifier. Since the area of the transmission side matching circuit can be reduced, it is possible to reduce the size and cost of the chip having the transmission amplifier, the reception amplifier, and the changeover switch, and thus the communication wireless device including the chip. Can be planned.

As in the first aspect of the invention, since the output impedance of the transmitting amplifier and the input impedance of the receiving amplifier inside the changeover switch can be reduced, the isolation characteristic of the changeover switch can be improved. Since the antenna side matching circuit that matches the characteristic impedance of the wiring and the input impedance of the receiving amplifier is connected between the wiring and the changeover switch, the transmitting amplifier, the receiving amplifier and the changeover switch are integrated into one chip. In this case, since the antenna side matching circuit can be provided outside the chip, it is possible to further promote the downsizing and cost reduction of the chip and the radio device for a communication device including the chip.

According to the transmitter / receiver circuit of the communication device radio of the present invention, the transmission signal output from the transmission amplifier is input to the changeover switch via the transmission side matching circuit and output from the changeover switch. Since the received signal is input to the receiving amplifier via the receiving side matching circuit, the characteristic impedance of the changeover switch can be optimized for the changeover switch, so that the area of the changeover switch can be reduced and the insertion loss of the through FET can be reduced. The matching circuit on the transmitting side need only have the function of matching the output impedance of the transmitting amplifier with the optimum characteristic impedance for the changeover switch, and the matching circuit on the receiving side changes the input impedance of the receiving amplifier to the changeover switch. Since it only needs to have the function of matching the optimum characteristic impedance, it matches the transmission side. Since the area of the road and the receiver matching circuit can be both reduced, it is possible to reduce the size and cost of the transmitter amplifier, communication radios having a chip and thus the chip having a receiver amplifier and the changeover switch.

As in the first aspect of the invention, since the output impedance of the transmission amplifier and the input impedance of the reception amplifier inside the changeover switch can be reduced, the isolation characteristic of the changeover switch can be improved. , The matching circuit on the antenna side for matching the characteristic impedance of the wiring and the characteristic impedance most suitable for the changeover switch is connected between the wiring and the changeover switch, so that the transmission amplifier, the reception amplifier and the changeover switch are integrated into one chip. In this case, since the antenna side matching circuit can be provided outside the chip, it is possible to further reduce the size and cost of the chip and the radio device for a communication device including the chip.

According to the transmitter / receiver circuit of the radio for communication equipment according to the invention of claim 7, as in the invention of claim 4, it is not necessary to particularly provide the shunt FET on the transmission side of the changeover switch. The transceiver circuit is simplified. For this reason, the number of parts is reduced, so that the miniaturization of the communication wireless device is promoted and the reliability is improved.

According to the semiconductor integrated circuit device of the eighth aspect of the present invention, the transmission amplifier, the reception amplifier, the changeover switch and the reception side matching circuit in the transmission / reception circuit of the communication radio device according to the first aspect of the present invention can be secured. It can be made into one chip.

According to the semiconductor integrated circuit device of the ninth aspect, the transmitting amplifier, the receiving amplifier, the changeover switch, the receiving side matching circuit and the antenna side matching circuit can be integrated into one chip.

According to the semiconductor integrated circuit device of the tenth aspect of the present invention, since it is not necessary to particularly provide the transmission side shunt FET of the changeover switch, the transmission / reception circuit of the communication radio can be simplified and the number of parts can be reduced. Can be planned
It is possible to eliminate the adjustment of the transmitter / receiver circuit, which has required a lot of labor in the past, to promote miniaturization of the communication radio and to improve reliability, and at the same time, to transmit the amplifier, the receiver amplifier, the changeover switch, and the like. The matching circuit on the receiving side can be easily and surely integrated into one chip.

According to the semiconductor integrated circuit device of the eleventh aspect of the invention, as in the tenth aspect of the invention, the transmission / reception circuit of the communication radio can be simplified, so that the number of parts can be reduced and the conventional structure can be achieved. Adjustment of the transmission / reception circuit, which requires a great deal of labor, can be eliminated, miniaturization of the communication radio device can be promoted, and reliability can be improved, and the transmission amplifier and the changeover switch can be easily and surely provided. Can be made into chips.

According to the communication radio device of the invention of claims 12 to 14, miniaturization and cost reduction can be achieved, and the isolation characteristic of the changeover switch can be improved.

[Brief description of drawings]

1A is a schematic configuration diagram of a transmission / reception circuit of a conventional communication wireless device, and FIG. 1B is a schematic configuration diagram of a transmission / reception circuit of a communication wireless device according to a first embodiment of the present invention. .

FIG. 2 is a diagram showing a specific configuration of a transmission / reception circuit of the communication wireless device according to the first embodiment.

FIG. 3 is a Smith diagram showing an impedance matching state for explaining the operation of the transmission / reception circuit of the communication wireless device according to the first embodiment.

FIG. 4 is a schematic configuration diagram of a transmission / reception circuit of a communication wireless device according to a second embodiment of the present invention.

5A is a schematic configuration diagram of a transmission / reception circuit of a communication wireless device according to a third embodiment of the present invention, and FIG. 5B is a transmission / reception of the communication wireless device according to a fourth embodiment of the present invention. It is a schematic block diagram of a circuit.

FIG. 6 is a diagram illustrating optimum characteristic impedance of a changeover switch in the transmission / reception circuit of the communication wireless device according to the fourth embodiment.

FIG. 7 is a diagram showing a specific configuration of a transmission / reception circuit of a communication wireless device according to a fifth embodiment of the present invention.

FIG. 8 is a diagram showing a specific configuration of a transmission / reception circuit of a conventional communication wireless device.

[Explanation of symbols]

 1 Semiconductor Substrate 10 Transmission Amplifier 11A Transmission Wave Input Terminal 12 Front Stage FET 13 Matching Circuit 14 Rear Stage FET 15A Power Supply Terminal 20 Reception Low Noise Amplifier 22 Low Noise FET 23A Reception Wave Output Terminal 30 Antenna 40 Changeover Switch 41A Antenna Side Input Output terminal 42A Switch control signal input terminal 43 First FET (transmission side shunt FET) 44 Second FET (transmission side through FET) 45 Third FET (reception side through FET) 46 Fourth FET (reception side shunt) FET) 51 First wiring 60A Reception side matching circuit 60C Transmission side matching circuit 60D Reception side matching circuit 70A Antenna side matching circuit 81A First coupling capacitance 82A Second coupling capacitance

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Internal reference number FI Technical indication H03K 17/693 9184-5K H03K 17/693 A

Claims (14)

[Claims] 1. A transmission amplifier that amplifies and outputs an input transmission signal, a reception amplifier that amplifies and outputs an input reception signal, and a transmission signal via wiring having a predetermined characteristic impedance. It has an antenna side input / output terminal for outputting a reception signal from the antenna through the wiring while outputting to the antenna, and the transmission signal output from the transmission amplifier is input and input without passing through a matching circuit. Switching for switching between a first connection state in which a transmission signal is output to the antenna side input / output terminal and a second connection state in which a reception signal input from the antenna side input / output terminal is output to the reception amplifier A switch, and is connected between the changeover switch and the receiving amplifier, and has an input impedance of the receiving amplifier and an output impedance of the transmitting amplifier. And a matching circuit on the antenna side that is connected between the wiring and the changeover switch and that matches the characteristic impedance of the wiring and the output impedance of the transmission amplifier. A transmitter / receiver circuit for a communication radio. 2. A first coupling capacitance connected between the transmission amplifier and the changeover switch, and a second coupling capacitance connected between the changeover switch and the reception side matching circuit. The transmission / reception circuit of the communication wireless device according to claim 1, wherein the transmission / reception circuit is provided. 3. The transmission / reception circuit of a communication radio device according to claim 1, wherein the antenna side matching circuit is directly connected to the antenna side input / output terminal. 4. The change-over switch has a transmitting side through FET and a transmitting side shunt FET connected in series, and a receiving side through FET and a receiving side shunt FET connected in series, wherein the transmitting amplifier is , And at least one amplification FET for amplifying the input transmission signal, wherein the final-stage amplification FET of the transmission amplifier also serves as the transmission-side shunt FET of the changeover switch. A transmission / reception circuit of the communication wireless device according to Item 1. 5. A transmission amplifier that amplifies and outputs an input transmission signal, a reception amplifier that amplifies and outputs an input reception signal, and a transmission signal via wiring having a predetermined characteristic impedance. A first output terminal that outputs an output signal to the antenna and inputs an input signal from the antenna through the wiring, and outputs a transmission signal input from the transmission amplifier to the input / output terminal on the antenna; And a reception signal input from the antenna side input / output terminal to the reception amplifier without passing through a matching circuit.
And a changeover switch for changing over to a connection state of the transmission amplifier, and a transmission side matching circuit that is connected between the transmission amplifier and the changeover switch to match the output impedance of the transmission amplifier and the input impedance of the reception amplifier A circuit, and an antenna-side matching circuit that is connected between the wiring and the changeover switch and that matches the characteristic impedance of the wiring and the input impedance of the receiving amplifier. The transceiver circuit of the radio. 6. A transmission amplifier that amplifies and outputs an input transmission signal, a reception amplifier that amplifies and outputs an input reception signal, and a transmission signal via wiring having a predetermined characteristic impedance. A first output terminal that outputs an output signal to the antenna and inputs an input signal from the antenna through the wiring, and outputs a transmission signal input from the transmission amplifier to the input / output terminal on the antenna; Between the transmission amplifier and the changeover switch, and a changeover switch for changing over between the connection state of 1) and the second connection state of outputting the reception signal input from the antenna side input / output terminal to the reception amplifier. A transmission side matching circuit that is connected to match the output impedance of the transmission amplifier and the characteristic impedance most suitable for the changeover switch; Between the switch and the receiving amplifier, and a receiving side matching circuit for matching the input impedance of the receiving amplifier with the characteristic impedance most suitable for the changeover switch, and between the wiring and the changeover switch. And a matching circuit on the antenna side for matching the characteristic impedance of the wiring with the characteristic impedance most suitable for the changeover switch. 7. A transmission amplifier having at least one amplification FET for amplifying an input transmission signal, a reception amplifier for amplifying and outputting an input reception signal, and outputting the transmission signal to an antenna. An antenna side input / output terminal for inputting a reception signal from the antenna, a transmission side through FET and a transmission side shunt FE connected in series
T, a receiving side through FET and a receiving side shunt FET connected in series, and a first connection state in which a transmission signal input from the transmission amplifier is output to the antenna side input / output terminal and the antenna. A switching switch for switching a reception signal input from the side input / output terminal to a second connection state for outputting the reception signal to the reception amplifier, and the amplification FET at the final stage of the transmission amplifier is the switching switch. A transmitter / receiver circuit for a communication radio, which doubles as a shunt FET on the transmitter side. 8. A semiconductor substrate, a transmission amplifier that is formed on the semiconductor substrate and amplifies and outputs an input transmission signal, and an input reception signal that is formed on the semiconductor substrate. A receiving amplifier for amplifying and outputting a signal, a wiring formed on the semiconductor substrate and having a predetermined characteristic impedance of a transmission signal, and a matching between the characteristic impedance of the wiring and the output impedance of the transmitting amplifier A transmission output from the transmission amplifier, which has an antenna-side input / output terminal for outputting a reception signal from the antenna through the wiring and the antenna-side matching circuit while outputting to the antenna through the antenna-side matching circuit A first signal is input without passing through a matching circuit, and the input transmission signal is output to the antenna side input / output terminal.
And a second connection state in which a reception signal input from the input / output terminal on the antenna side is output to the reception amplifier, and a changeover switch formed on the semiconductor substrate. Integrated circuit, which is connected between the amplifier for output and the changeover switch, and which includes a receiving side matching circuit for matching the input impedance of the receiving amplifier with the output impedance of the transmitting amplifier. apparatus. 9. The semiconductor integrated circuit device according to claim 8, wherein the antenna side matching circuit is formed on the semiconductor substrate. 10. The transmission switch includes a transmission-side through FET and a transmission-side shunt FET connected in series,
A receiving side through FET and a receiving side shunt FET connected in series, the transmission amplifier has at least one amplification FET for amplifying an input transmission signal, and the final stage of the transmission amplifier. 9. The semiconductor integrated circuit device according to claim 8, wherein the amplifying FET also serves as a transmission side shunt FET of the changeover switch. 11. A semiconductor substrate, a transmission amplifier formed on the semiconductor substrate and having at least one amplification FET for amplifying an input transmission signal, and formed on the semiconductor substrate. An antenna-side input / output terminal for outputting a transmission signal to the antenna and inputting a reception signal from the antenna, a transmission-side through FET and a transmission-side shunt FET connected in series, a reception-side through FET connected in series, and A reception side shunt FET, for receiving a transmission signal input from the transmission amplifier to the antenna side input / output terminal and a reception signal input from the antenna side input / output terminal A switching switch for switching to a second connection state for outputting to the amplifier, and the amplification FET at the final stage of the transmission amplifier is the switching A semiconductor integrated circuit device which also functions as a shunt FET on the transmission side of the switch. 12. An antenna, a wire connected to the antenna and having a predetermined characteristic impedance, a transmission amplifier for amplifying and outputting an input transmission signal, and an amplification and outputting for an input reception signal. It has a reception amplifier and an antenna side input / output terminal for outputting a transmission signal to the antenna via the wiring and inputting a reception signal from the antenna via the wiring. The output signal is input without passing through a matching circuit, and the first connection state in which the input transmission signal is output to the antenna-side input / output terminal and the reception signal input from the antenna-side input / output terminal are described above. A change-over switch for changing over to a second connection state for outputting to the receiving amplifier; and a change-over switch connected between the receiving amplifier and the change-over switch, A receiving side matching circuit for matching the input impedance of the receiving amplifier with the output impedance of the transmitting amplifier, and the characteristic impedance of the wiring and the input of the transmitting amplifier, which are connected between the wiring and the changeover switch. A communication wireless device, comprising: an antenna side matching circuit for matching impedance. 13. An antenna, a wire connected to the antenna and having a predetermined characteristic impedance, a transmission amplifier for amplifying and outputting an input transmission signal, and an amplification and output for an input reception signal. It has a receiving amplifier and an antenna side input / output terminal for outputting a transmission signal to the antenna through the wiring and inputting a reception signal from the antenna through the wiring. A first connection state in which an input transmission signal is output to the antenna side input / output terminal and a second connection state in which a reception signal input from the antenna side input / output terminal is output to the reception amplifier without passing through a matching circuit A changeover switch for changing over to a connection state, and an output impeller of the transmission amplifier connected between the transmission amplifier and the changeover switch. Connected between the wiring and the changeover switch, and the transmission side matching circuit for matching the input impedance of the receiving amplifier with the transmitter side matching circuit for matching the characteristic impedance of the wiring and the input impedance of the receiving amplifier. A communication radio device comprising a matching circuit on the antenna side. 14. An antenna, a wire connected to the antenna and having a predetermined characteristic impedance, a transmission amplifier for amplifying and outputting an input transmission signal, and an amplification and outputting for an input reception signal. A receiving amplifier and an antenna side input / output terminal for outputting a transmission signal to the antenna through the wiring and inputting a reception signal from the antenna through the wiring, and are input from the transmission amplifier. Switching for switching between a first connection state in which a transmission signal is output to the antenna side input / output terminal and a second connection state in which a reception signal input from the antenna side input / output terminal is output to the reception amplifier A switch, which is connected between the transmission amplifier and the changeover switch, and is optimal for the output impedance of the transmission amplifier and the changeover switch. A transmission side matching circuit that matches the characteristic impedance, and a receiver that is connected between the changeover switch and the reception amplifier and that matches the input impedance of the reception amplifier and the characteristic impedance most suitable for the changeover switch. A side matching circuit, and an antenna side matching circuit that is connected between the wiring and the changeover switch and that matches the characteristic impedance of the wiring with the characteristic impedance optimum for the changeover switch. A radio for communication.