JP2003198414A - High frequency circuit, hybrid high frequency component and communication equipment using the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high frequency circuit which is simplified by reducing the number of components (elements) comprising the circuit and thereby enables reduction of the size, in particular, the height of a hybrid high frequency component and improvement of the performance thereof, and to provide a hybrid high frequency component and communication equipment in which reduction and the improvement are realized. <P>SOLUTION: The high frequency circuit is provided with: a switch part having a first common terminal, a first input terminal, a first output terminal and a first input/output terminal and for switching and connecting one of the first input terminal, the first output terminal; and the first input/output terminal to the first common terminal and a first diplexer having a second common terminal, a second input terminal and a third input terminal an the first input terminal is connected to the second common terminal. <P>COPYRIGHT: (C)2003,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 circuit used in a communication device such as a mobile communication system, a composite high-frequency component realizing the same, and a communication device using the same, and particularly to a high-frequency circuit compatible with a plurality of communication systems. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circuit, a composite high frequency component that realizes the circuit, and a communication device using the same.

At present, there are many communication systems / a plurality of high frequency bands as mobile communication devices. For example, as a TDMA system, E using 900 MHz band in Europe is used.
GSM (Extended Global; System)
m; communication) communication system and 1.
DCS (Digital; Cel) using 8 GHz band
There are two types of communication systems, a dual band mobile phone capable of operating with two communication systems. For example, Japanese Patent Laid-Open No. 2001-18590
No. 2 and DCS disclosed in Japanese Patent Laid-Open No. 2000-49651
The dual-band mobile phone of EGSM and EGSM corresponds to the frequency band of DCS and the frequency band of EGSM, and sometimes D
It communicates in the CS frequency band, and sometimes in the EGSM frequency band. As described above, by handling the frequency bands of a plurality of standards, when the communication of the frequency band of one standard is impossible, the communication can be performed in the frequency band of the other standard.

Furthermore, for example, a PCS (Personal Communicat) using the 1.9 GHz band is used.
In addition to other communication systems such as an Ion Services) communication system, a triple band mobile phone capable of operating with three communication systems has been proposed. JP 200
No. 0-165288 discloses a composite high frequency component and a mobile communication device capable of operating in three communication systems.

FIG. 1 is a block diagram showing a front end portion of a general triple band portable telephone, and 1.8 for a first communication system and a second communication system having frequencies close to each other.
The figure shows an example of a case where a DCS in the GHz band, a PCS in the 1.9 GHz band, and a 900 MHz band EGSM are used as a third communication system having a different frequency.

A composite high frequency component 20 used in a triple band mobile phone includes an antenna 1, a diplexer 2, first to third diode switches 3 to 5, first and second.
The filters 6 and 7 are provided. The diplexer 2 serves to combine the DCS, PCS or EGSM transmission signals at the time of transmission and to distribute the reception signals to the DCS, PCS or EGSM at the time of reception. The first diode switch 3 is connected to the DCS / PCS transmitter side and the DCS / PS side.
The second diode switch 4 switches between the CS receiver and the DCS receiver Rxd and the PCS receiver Rx.
The third diode switch 5 is switched to the E side.
It plays a role of switching between the transmitting unit Txg side and the receiving unit Rxg side of GSM. The first filter 6 passes DCS and PCS transmission / reception signals, attenuates the second and third harmonics, and the second filter 7 passes EGSM transmission / reception signals and generates third harmonics. It plays the role of damping.

[0006]

A composite high frequency component 20.
Since it is mounted on a communication device such as a mobile phone, it is required to be downsized. At the same time, it is required to improve the performance of composite high frequency components for improving communication quality.

The conventional composite high frequency component 20 including a diode switch composed of a diode, a capacitor, an inductor, etc., a diplexer composed of a coil and a capacitor, and a filter is composed of a large number of components (elements), It has a complicated circuit configuration. In particular, chip components such as diodes that cannot be formed inside the multi-layer substrate are mounted on the multi-layer substrate, which hinders downsizing of the composite high-frequency component. In addition, since a large number of components (elements) are composed of complicated circuits, circuit wiring for connecting the components (elements) to each other is complicatedly routed over a plurality of substrates within the multilayer substrate. In order to connect components (elements) arranged on different boards, vias are usually provided on the boards and connected. As a result, the circuit wiring becomes long, which may cause an increase in transmission loss and noise generation due to coupling between the circuit wirings.

For example, in the multi-band high frequency switch module disclosed in Japanese Unexamined Patent Publication No. 2000-49651, a switch for switching transmission / reception of a communication system is composed of a diode, a transmission line and a capacitor, and the transmission line and the like use a plurality of vias. Of the transmission line and capacitors formed on another substrate are similarly connected via the vias. As a result, the thickness of the multi-layer substrate becomes large and it may be difficult to reduce the height.

Therefore, an object of the present invention is to reduce the number of parts (elements) constituting a circuit to simplify the circuit, and to reduce the size of a composite high-frequency component, in particular, to reduce the height and the high frequency. It is to provide a circuit, a composite high frequency component and a communication device that realize the circuit.

[0010]

A high frequency circuit according to claim 1 of the present invention comprises a first common terminal and a first common terminal.
An input terminal, a first output terminal, a second output terminal, and a first input / output terminal, and a first input terminal, a first output terminal, a second output terminal, and a first input / output. Any one of the terminals includes a switch unit that is switchably connected to the first common terminal, and a diplexer having a second common terminal, a second input terminal, and a third input terminal, The first
Is connected to the second common terminal.

Further, the high frequency circuit of the present invention is the first
A filter is connected between the input terminal of and the second common terminal. Examples of the filter include a low pass filter.

Furthermore, the high-frequency circuit of the present invention is characterized in that the switch section includes a switch element including a semiconductor element and a capacitor. As a switching element including a semiconductor element, a switching element made of a GaAs element or a SiGe element can be mentioned.

A composite high frequency component of the present invention is a composite high frequency component having a multi-layer substrate formed by laminating a plurality of dielectric substrates, the first common terminal, the first input terminal and the first common terminal. An output terminal, a second output terminal, and a first input / output terminal, and any one terminal of the first input terminal, the first output terminal, the second output terminal, and the first input / output terminal. But first
And a diplexer having a second common terminal, a second input terminal and a third input terminal, wherein the first input terminal is the second common terminal. And the switch unit includes a switch element including a GaAs semiconductor element and a capacitor, the switch element is mounted on the multilayer substrate, and the diplexer is formed inside the multilayer substrate. And

In the composite high frequency component of the present invention, a filter is connected between the first input terminal and the second common terminal, and the filter is formed inside the multilayer substrate. Characterize. Examples of the filter include a low pass filter.

Further, the composite high-frequency component of the present invention is characterized in that the capacitor forming the switch section is mounted as a chip component on the multilayer substrate.

A communication device of the present invention is characterized by using the high frequency circuit.

A communication device of the present invention is characterized by using the composite high frequency component.

In the high frequency circuit and the composite high frequency component of the present invention, a surface acoustic wave filter is connected to each of the first output terminal and the second output terminal, and the surface acoustic wave filter is mounted on the surface of the substrate. May be.

In the high frequency circuit and the composite high frequency component of the present invention, a circuit including an inductor and a capacitor for removing noise is connected to the first common terminal, and the inductor and the capacitor are formed inside the multilayer substrate. Alternatively, it may be formed by mounting a chip component on the surface of the substrate.

With the above-described structure, the high-frequency circuit and the composite high-frequency component of the present invention can reduce the number of components (elements) constituting the circuit, so that the circuit configuration is simplified. In addition, since the transmission line of the component (element) forming the switch unit for switching the transmission and reception, which is formed over a plurality of substrates, can be omitted, the multilayer substrate can be thinly formed, and the entire composite high-frequency component can be manufactured. It is possible to reduce the size and height. Furthermore, since the length of the wiring for connecting even the components (elements) forming the circuit is shortened, it is possible to suppress an increase in transmission loss and prevent the generation of noise due to the coupling between the wirings.

Further, the high-frequency circuit and the composite high-frequency component of the present invention include the first communication system and the second communication system in which the frequency bands used are close to each other, and the frequency bands used in the first and second communication systems are separated from each other. It is possible to support the third communication system. Further, the first communication system may be a CDMA communication system, and the transmitter and the receiver of the first communication system may be high-frequency circuits connected only by circuit wiring or by circuit wiring. As a CDMA communication system, a W-CDMA communication system or UMTS (Universal Mo
bile Telecommunications System) A communication system etc. are mentioned.

In the composite high frequency component of the present invention, a diplexer, a switch portion including at least a switch element, and a filter circuit are integrated on a multilayer substrate to form a GaAs
The switch element including the semiconductor element is mounted on the multilayer substrate,
By forming the diplexer and the filter circuit inside the multilayer substrate, the composite high frequency component can be downsized. Furthermore, the same effect can be obtained when a circuit for removing noise is also integrated with the multilayer substrate.

Further, the composite high frequency component of the present invention uses the GaAs semiconductor element in the switch portion, so that the number of components (elements) constituting the switch portion for switching between transmission and reception of a plurality of communication systems can be reduced. Therefore, the high frequency circuit is simplified. Further, since the number of components (elements) mounted on the multilayer substrate can be reduced, the composite high frequency component can be downsized. Furthermore, workability of component mounting is improved by reducing the number of components mounted on the multilayer substrate.

In the high frequency circuit and the composite high frequency component of the present invention, since the low pass filter is connected between the switch section and the diplexer, the diplexer and the EGS are connected.
The number of low-pass filters can be reduced as compared with the case of connecting between the M transmission terminal TX1 and the DCS transmission section terminal TX2. That is, the harmonics of the transmission signal can be removed without increasing the number of parts (elements).

The capacitor forming the switch portion of the composite high frequency component of the present invention has a function of a DC current cutting capacitor. Normally, a capacitor with a large capacity is used for DC current cutting, but when it is used as an inner layer on a multilayer substrate, the electrode area of the capacitor electrode must be increased or the capacitor electrode must be formed over multiple layers. Therefore, it may hinder the miniaturization of the multilayer substrate. However, the composite high-frequency component of the present invention enables the miniaturization of the multilayer substrate and hence the miniaturization of the composite high-frequency component because the capacitors forming the switch section are mounted on the multilayer substrate.

The communication device of the present invention also exhibits the same operational effect by using the high frequency circuit and the composite high frequency component of the present invention.

[0027]

BEST MODE FOR CARRYING OUT THE INVENTION A composite high frequency component 201 which is one embodiment of the present invention has a structure as shown in FIG.

2 and 3, a first diplexer (not shown) formed inside a multi-layer substrate 101 having a dielectric substrate such as glass ceramic as an insulating layer and a conductive layer containing Ag or an Ag alloy as a main component. 21, low-pass filter 61, GaAs semiconductor element 315 and capacitors 316, 317, 318, 31 mounted on a multilayer substrate
The switch unit 31 is composed of 9, 320. Further, the multilayer substrate 101 has a substantially rectangular parallelepiped shape, and
A plurality of castellations 401, each of which has a semi-cylindrical concave portion on the lower side and an inner side surface of which is a conductor layer, are formed on one side surface. The composite high frequency component 201 can be mounted and connected on another substrate by this castellation 401. The castellation 401 corresponds to an antenna terminal in a high frequency circuit, a transmission / reception unit terminal of each communication system, a control terminal, a ground terminal, and the like.

The first and second communication systems in which the frequency bands used are formed close to each other in the composite high frequency component 201 of the present invention, and the frequency bands used in the first and second communication systems are separated from each other. The high frequency circuit 9 used in the triple band mobile phone compatible with the third communication system will be described with reference to FIGS. 3 and 4. Figure 3
Is a block diagram, and FIG. 4 is a circuit diagram. Here, in this embodiment, as the first communication system, a UMTS (Universal Mobile Telecommumu) of a CDMA communication system is used.
nicationsSystem), TDMA as the second communication system
The DCS of the system and the EGSM of the TDMA system as the third communication system.

In FIGS. 3 and 4, a high frequency circuit 9 is connected to an antenna terminal ANT to switch a transmission signal and a reception signal of each communication system, an EGSM and a DC.
Diplexer 2 connected to the transmission unit of the S communication system
1 and a low pass filter 61 for attenuating the second harmonic and the third harmonic in the transmission signal from the transmission unit from the EGSM and DCS communication system. Switch part 3
Reference numeral 1 denotes a first common terminal 314 connected to the antenna terminal ANT and a first filter terminal 611 of the low pass filter.
And a first input / output terminal 312 connected to the transmitter / receiver terminal TRX1 of the UMTS.
And a first output terminal 313 connected to the receiver terminal RX1 of the EGSM and a second output terminal 321 connected to the receiver terminal RX2 of the DCS.

The switch section 31 includes a switch element 315 including a GaAs semiconductor element and capacitors 316 and 317.
318, 319 and 320. The switch element has a first control terminal VC1 for controlling connection / disconnection between the first common terminal and the first input terminal, and a second control terminal VC1 for controlling connection / disconnection between the first common terminal and the first input / output terminal. Control terminal VC2, third common terminal VC3 for controlling connection / disconnection between the first common terminal and first output terminal, first common terminal and first common terminal
A fourth control terminal V for controlling connection / disconnection of the second output terminal
It has C4. Here, the capacitors 316 and 31
7, 318, 319 and 320 are control terminals VC1 and VC
2, it has a function of cutting the DC current from VC3, VC4, and the one having a capacity of about 30 pF or more is often used.

The diplexer 21 has a low-pass filter 6
The second common terminal 211 connected to the first second filter terminal 612 and the second common terminal 211 connected to the DCS transmitter terminal TX2.
It has an input terminal 212 and a third input terminal 213 connected to the transmitter terminal TX1 of the EGSM. Further, the diplexer 21 has a function of a high-pass filter that passes the transmission signal from the DCS transmission unit terminal TX2 between the second common terminal 211 and the second input terminal 212, and the second common terminal 211 and the third common terminal 211. Between the input terminal 213 of the
It has the function of a low-pass filter that allows the transmission signal from the transmission unit terminal TX1 to pass.

The diplexer 21 includes the capacitor 12
1 and 122 and an inductance 123, and a high pass filter including capacitors 127, 128 and 129 and an inductance 130.

The diplexer 21 described above is a combination of a low-pass filter and a high-pass filter, but the present invention is not limited to this, and a low-pass filter, a high-pass filter, a notch filter, a band-pass filter or the like other than this combination may be used. You may use the diplexer arbitrarily combined.

The low-pass filter 61 is a switch unit 31.
Is connected between the first input terminal 311 and the second common terminal 211 of the diplexer 21. The low-pass filter 61 includes capacitors 136, 137, 138, 13
9 and 140 and inductances 141 and 142, and is composed of a two-stage low-pass filter

The high frequency circuit 9 of the present invention having such a configuration operates as follows when transmitting or receiving in each communication system. The transmission signal of EGSM is E
The input from the transmitter terminal TX1 of the GSM is input to the second input terminal 213 of the diplexer 21, and the diplexer 21
Is output to the second common terminal 211 of the first diplexer 21 and is input to the first input terminal 311 of the switch unit 31 via the low-pass filter 61. Is output from the first common terminal 314 of. At this time, a DC voltage is applied to the first control terminal VC1 of the switch element 315 so as to connect the first common terminal 314 and the first input terminal 311, and the second, third, and fourth control terminals VC2 , VC3 and VC4 are applied with a DC voltage so as to disconnect the first input / output terminal, the first output terminal and the second output terminal. On the other hand, EG
The received signal of the SM receives the first common terminal 3 of the switch unit 31.
14 is input, is output from the first output terminal 313, and is sent to the EGSM receiver terminal RX1. At this time, a DC voltage is applied to the third control terminal VC3 of the switch element 315 so as to connect the first common terminal 314 and the first output terminal 313, and the first control terminal VC1 and the second control terminal VC2 are connected. The fourth control terminal VC4 is connected to the first input terminal 311 and the
A DC voltage is applied so as to disconnect the 1 input / output terminal 312 and the second output terminal.

The DCS transmission signal is input from the DCS transmission unit terminal TX2 to the third input terminal 212 of the diplexer 21, passes through the high-pass filter forming the first diplexer 21, and passes through the second diplexer 21 of the diplexer 21. Is output to the common terminal 211 of the low-pass filter 6
1 through the first input terminal 311 of the switch unit 31.
And is output from the first common terminal 314 of the switch unit 31. At this time, the first common terminal 314 and the first input terminal 3 are connected to the first control terminal VC1 of the switch element 315.
DC voltage is applied so as to connect to
A DC voltage is applied from the third and fourth control terminals VC2, VC3, and VC4 so as to disconnect the first input / output terminal, the first output terminal, and the second output terminal. On the other hand, the received signal of DCS is input from the first common terminal 314 of the switch unit 31 and output from the second output terminal 321. The output DCS reception signal is sent to the DCS reception unit terminal RX2. At this time, the fourth control terminal V of the switch element 315
A DC voltage is applied to C4 so as to connect the first common terminal 314 and the second output terminal 321, and the first control terminal V
C1, the second control terminal VC2 and the third control terminal VC3,
A DC voltage is applied so as to disconnect the first input terminal 311 and the first input / output terminal 312 first output terminal.

The UMTS transmission signal is input from the UMTS transmission unit terminal TRX1 to the first input / output terminal 312 of the switch unit 31, and is output from the first common terminal 314 of the switch unit 31. At this time, the switch element 315
A DC voltage is applied to the first control terminal VC2 of the above so as to connect the first common terminal 314 and the first input / output terminal 312, and the first, third, and fourth control terminals VC1, VC3, and VC4 The first input terminal 311 and the first output terminal 313 and the second
A DC voltage is applied to the output terminal 321 of the device so as to disconnect it. On the other hand, the received signal of UMTS is input from the first common terminal 314 of the switch unit 31, and the first input / output terminal 3
It is output from 12. The output UMTS received signal is
It is sent to the UMTS receiver terminal TRX1. At this time,
Similar to the case of transmission, the first control terminal V of the switch element 315
C2 has a first common terminal 314 and a first input / output terminal 312.
A DC voltage is applied so as to connect to the first input terminal 311 from the first and third control terminals VC1, VC3, and VC4.
A DC voltage is applied so that the first output terminal 313 and the second output terminal 321 are disconnected.

In the case of a triple band mobile phone of EGSM, DCS and UMTS, the EGSM transmission signal is
880MHz to 915MHz, received signal is 925MH
z from 960 MHz, DCS transmission signal is 1710 MH
z to 1785 MHz, received signal from 1805 MHz to 1880 MHz, UMTS transmitted signal from 1920 MHz
To 1980 MHz, the received signal is from 2110 MHz to 2
170 MHz. Therefore, the switch element 315 is
A GaAs MMIC made of a GaAs semiconductor whose frequency band is about 1000 MHz to 2000 MHz is used. In addition, the switching of transmission and reception of each communication system is G
Since it can be performed only by using aAsMMIC,
The number of parts (elements) constituting the high frequency circuit is reduced, and the composite high frequency part can be downsized. Since the GaAs MMIC is configured as a chip component, it is mounted on a multi-layer substrate when used for a composite high frequency component. Also, GaA
The connection between each terminal of the sMMIC and the components (elements) such as the first and second diplexers and the low pass filter is connected to the diplexer and the low pass filter formed in the multilayer substrate via the electrode pads (not shown).

On the other hand, since the GaAsMMIC is a device which is very susceptible to static electricity, a static electricity prevention circuit may be added to the high frequency circuit. Specifically, a circuit including a capacitor and an inductance is provided between the antenna terminal and the first common electrode of the switch section 31. The capacitor and the inductor may be mounted and formed as chip parts on the multi-layer substrate, but if the static electricity prevention circuit is also formed on the multi-layer substrate, the miniaturization of the composite high frequency component can be maintained.

Although the present invention has been described with reference to the embodiments, the present invention is not limited to the embodiments, and it is needless to say that the invention can be appropriately modified and applied without departing from the scope of the invention. . For example, a surface acoustic wave filter (SA) is provided to each of the first output terminal and the second output terminal.
W filter) may be connected. When using a high-frequency circuit with a SAW filter for composite high-frequency components, S
The AW filter is mounted on the multilayer substrate. You may mount a SAW filter in the recessed part provided in the multilayer substrate. Further, the recess may be formed on the surface on which the GaAsMMIC chip element is mounted, but if it is formed on the bottom surface of the multilayer substrate on which the GaAsMMIC chip element is not mounted, the multilayer substrate is downsized in plan view. Therefore, it is preferable.

Further, the transmitter / receiver terminal TR of the UMTS
A duplexer for switching between UMTS transmission signals and reception signals may be connected to X1.

[Brief description of drawings]

FIG. 1 is a block diagram of a triple-band high-frequency circuit used in a conventional triple-band mobile phone.

FIG. 2 is a perspective view of a composite high frequency component according to an embodiment of the present invention.

FIG. 3 is a block diagram of a high frequency circuit that is an embodiment of the present invention.

FIG. 4 is a high frequency circuit diagram showing an embodiment of the present invention.

[Explanation of symbols]

9 high frequency circuit 311 First input terminal 312 First input / output terminal 313 First output terminal 314 1st common terminal 31 Switch part 315 switch element 316-320 capacitors 21 First Diplexer 22 Second diplexer 211 Second common terminal 212 Second input terminal 213 Third input terminal 61 low pass filter 201 Composite high frequency components 101 multilayer substrate ;

Claims (8)

[Claims] 1. A first input terminal, a first output having a first common terminal, a first input terminal, a first output terminal, a second output terminal, and a first input / output terminal. Any one of the terminal, the second output terminal, and the first input / output terminal is the first
And a diplexer having a second common terminal, a second input terminal, and a third input terminal, wherein the first input terminal is the second common terminal. A high-frequency circuit characterized by being connected to a common terminal. 2. The high frequency circuit according to claim 1, wherein a filter is connected to the first input terminal and the second common terminal. 3. The high frequency circuit according to claim 1, wherein the switch unit includes a switch element including a semiconductor element and a capacitor. 4. A composite high frequency component having a multilayer substrate formed by laminating a plurality of dielectric substrates, the first common terminal, the first input terminal, the first output terminal and the second common terminal. An output terminal and a first input / output terminal, and any one terminal of the first input terminal, the first output terminal, the second output terminal, and the first input / output terminal is the first common terminal. A switch part that is switchably connected to the terminal, a second common terminal, a second input terminal, and a third
An input terminal of a diplexer, the first input terminal is connected to the second common terminal, the switch unit includes a switch element including a GaAs semiconductor element and a capacitor, and the switch element is A composite high frequency component mounted on the multilayer board, wherein the diplexer is formed inside the multilayer board. 5. The composite according to claim 4, wherein a filter is connected to the first input terminal and the second common terminal, and the filter is formed inside the multilayer substrate. High frequency components. 6. The composite high frequency component according to claim 4, wherein the capacitor forming the switch section is mounted as a chip component on a multilayer substrate. 7. A communication device using the high frequency circuit according to claim 1. Description: 8. A communication device comprising the composite high frequency component according to claim 4. Description: