JP4485982B2 - High frequency switching module and wireless communication device - Google Patents

Description

  The present invention relates to a high-frequency switching module, and more particularly to a high-frequency switching module that is suitably used in a wireless communication device such as a multiband mobile wireless terminal.

  In recent years, mobile phone terminals have been widely used, and functions and services of mobile phone terminals have been improved. As this new mobile phone terminal, a multiband mobile phone terminal has been proposed. A multi-band mobile phone terminal can handle two or more transmission / reception systems, whereas an ordinary mobile phone terminal handles only one transmission / reception system. Accordingly, the user can select and use a convenient transmission / reception system according to the region, purpose of use, and the like.

Examples of multiband include a GSM (Global System for Mobile Communication) system using a 900 MHz band and a DCS (Digital Cellular System) system using a 1800 MHz band in Europe. Furthermore, in North America, there is a PCS (Personal Communication Services) system using the 1900 MHz band in addition to GSM.
FIG. 5 is a block diagram of a high-frequency switching module RFM for a general GSM / DCS dual-band mobile phone.

  The high-frequency switching module RFM includes a transmission system TX2 and a reception system RX2 of the transmission / reception system DCS, a transmission system TX1 and a reception system RX1 of the transmission / reception system GSM, and two transmission / reception systems GSM / DCS having different frequency bands, respectively. Demultiplexing circuit for demultiplexing to transmission / reception systems GSM and DCS, switch circuits SW1 and SW2 for switching between transmission system TX and reception system RX in transmission / reception systems DCS and GSM, and inputs from transmission systems TX1 and TX2, respectively. Low pass filters LPF1 and LPF2 for attenuating the generated harmonics. Further, a low pass filter LP3 is inserted between the branching circuit and the switch circuit SW2.

  In the dual-band high-frequency switching module RFM, the harmonics of the GSM transmission system TX1 can be attenuated not only by the low-pass filter LPF1, but also by the LPF in the branching circuit. The harmonics of the DCS transmission system TX2 can be attenuated not only by the low-pass filter LPF2, but also by the low-pass filter LPF3.

Also, PIN diode switch circuits as shown in FIG. 6 are used as the switch circuits SW1 and SW2. This PIN diode switch circuit disconnects the circuit by applying a bias voltage to the PIN diode. The λ / 4 line SL1 included in the reception system RX may be provided with a low-pass filter function for attenuating harmonics.
JP 2001-332902 A

  By the way, based on future market trends, it is expected that data transmission such as high-quality voice and images using a mobile phone terminal will be performed, and in order to cope with these, CDMA which is a code division multiple access system Construction of a transmission / reception system capable of transmitting large-capacity data such as (Code Division Multiple Access) and a next-generation transmission / reception system UMTS characterized by high-speed data transmission rate and multiplexing of communication channels is progressing.

Thus, in order to cope with a plurality of transmission / reception systems, it is necessary to support more bands with one module.
When it is necessary to support more bands in one module as described above, the dielectric substrate requires a surface layer space proportional to the number of bands, and the antenna switch module is required to be further miniaturized. .

Recently, a configuration using a high-frequency semiconductor switch, for example, a GaAs-SW (gallium arsenide switch), as a high-frequency switch that performs transmission / reception switching inside the antenna switch module has been studied with the aim of downsizing and low loss.
At that time, the antenna switch module is required to severely attenuate harmonics as well as to reduce loss in the passband.

In particular, not only the TX terminal but also the RX terminal is required to attenuate harmonics. Further, harmonic attenuation may be required at the UMTS / CDMA terminal.
The required value is about 10 dB for RX, which is relatively small compared to 30 dB for TX.
Therefore, it is conceivable to attenuate the harmonics by the branching circuit. However, if the harmonics are attenuated by the branching circuit, the loss in the reception passband also increases. Therefore, the attenuation of harmonics in the branching circuit is limited.

It is also conceivable to insert a low-pass filter at each RX terminal of the high-frequency switch. However, since a low-pass filter is inserted, the loss in the reception passband increases, and a reduction in loss cannot be achieved. Furthermore, as the number of ports increases, a low-pass filter is inserted into each terminal, but this is difficult from the viewpoint of miniaturization.
Accordingly, an object of the present invention is to provide a high-frequency switching module that is small in size, low in loss, and capable of attenuating harmonics without newly inserting a low-pass filter, and a wireless communication device equipped with the high-frequency switching module.

High-frequency switching module of the present invention, a dielectric multi-layer substrate comprising a plurality of dielectric layers, and the high frequency switch element mounting electrodes provided on the surface of the dielectric multilayer substrate, is mounted on the high-frequency switch element mounting electrode and, a plurality of different transmitting and receiving signals pass band, a high frequency switch device for switching the transmitting and receiving system by the transmission signal or reception signal, wherein the dielectric is provided et been on the surface or inside of the multilayer substrate, the terminal of the high-frequency switch element it is to have a filter circuit for attenuating harmonics of the transmission signal by being connected.
The high-frequency switch element comprises a semiconductor integrated circuit element. The penetrating one or more dielectric layers comprises a first conductive pattern for connecting the first via hole conductors each other of the plurality of first via-hole conductors and said plurality of said high-frequency switch device mounting electrode and the front Symbol dielectric multilayer Louis inductor Nsu adjustment electrodes to connect between the ground electrodes provided on the back surface of the substrate is provided inside the dielectric multi-layer substrate. A second via-hole conductor connected to the high-frequency switch element mounting electrode and penetrating one or more layers of the dielectric layer; a second conductor pattern connected to the second via-hole conductor; and the grounding electrode. A third via-hole conductor connected through one or more layers of the dielectric layer, and a third via-hole connected to the third via-hole conductor and facing the second conductor pattern via the dielectric layer A capacitance adjusting electrode which is formed of a conductor pattern and forms a capacitance between the high frequency switch element mounting electrode and the ground electrode is provided inside the dielectric multilayer substrate .

According to this configuration, the frequency characteristics of the high frequency switch element can be changed by setting the inductance adjustment electrode and the capacitance adjustment electrode connected from the high frequency switch element to the ground (GND). As a result, it is possible to attenuate harmonics, particularly harmonics included in the received signal, without adding a new low-pass filter.
The inductance adjustment electrode has a first formed on the dielectric layer for connecting a plurality of first via-hole conductor and the first via hole conductors each other of the plurality of penetrating one or more layers of the dielectric layer Since it is composed of a conductor pattern, it can be incorporated in a dielectric multilayer substrate, and the dielectric multilayer substrate can be miniaturized and the high-frequency switching module can be miniaturized.
The capacitance adjusting electrode is connected to the high frequency switching element mounting electrode and penetrates one or more layers of the dielectric layer, and is formed in the dielectric layer and is connected to the second via hole conductor. A connected second conductor pattern; a third via-hole conductor connected to the grounding electrode and penetrating one or more layers of the dielectric layer; and formed in the dielectric layer and connected to the third via-hole conductor. In addition, since the third conductor pattern is used, the dielectric multilayer substrate can be built in, and the dielectric multilayer substrate can be downsized and the high-frequency switching module can be downsized.

The high-frequency switch element is formed in two types for low frequency and high frequency, and two high-frequency switch element mounting electrodes corresponding to the high-frequency switch elements are provided, and for each high-frequency switch element mounting electrode, if placing the inductance adjusting electrodes and the capacitor Nsu adjustment electrode, for each communication system of different frequency bands of the low-frequency and high-frequency, can be independently is easily possible to adjust the harmonic attenuation .

Et al is, the present invention is equipped with a high-frequency switching module described above, in which according to the wireless communication system for a small low loss.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a block diagram for explaining an example of a high-frequency switching module RFM1 of a multiband-compatible mobile phone terminal.
This high-frequency switching module RFM1 is connected to one common antenna terminal ANT and is GSM850 (850 MHz band), GSM900 (900 MHz band), DCS (1800 MHz band), PCS (1900 MHz band), CDMA Cellular (800 MHz band), UMTS A function of switching six transmission / reception systems (2100 MHz band) is provided. The GSM850, GSM900, and CDMA Cellular transmission / reception systems are classified as low-frequency transmission / reception systems, and the low-frequency transmission / reception systems are classified as high-frequency transmission / reception systems. Further, the transmission system is represented as “TX” and the reception system is represented as “RX”.

  This high-frequency switching module RFM1 includes a demultiplexing circuit DIP1 that separates a low-frequency transmission / reception system (GSM850, GSM900, CDMA Cellular) and a high-frequency transmission / reception system (DCS, PCS, UMTS), CDMA Cellular-TX / RX (TXRX5), GSM850. / 900-TX (TX12), GSM850-RX (RX1), high-frequency switch element SW1 for switching GSM900-RX (RX2), UMTS-TX / RX (TXRX6), DCS / PCS-TX (TX34), DCS-RX (RX3) and a high-frequency switch element SW2 for switching between PCS-RX (RX4).

  The high-frequency switch elements SW1 and SW2 are obtained by forming a circuit pattern on an integrated circuit substrate whose main component is a GaAs (gallium arsenide) compound, Si (silicon) or Al2O3 (sapphire). In particular, in order to reduce the size and the loss, the circuit is preferably formed of a circuit having a GaAs J-FET structure formed on a substrate containing a GaAs compound as a main component.

In the path between the branching circuit DIP1 and the GSM850 / 900-TX terminal (TX12), a low-pass filter LPF1 that attenuates harmonics of the transmission signal, the branching circuit DIP1 and the DCS / PCS-TX terminal (TX34). ) Is connected to a low-pass filter LPF2 that attenuates harmonics of the transmission signal.
As shown in FIG. 1, the high-frequency semiconductor integrated circuit elements SWIC constituting the high-frequency switch elements SW1 and SW2 are formed of separate integrated circuit elements corresponding to the high-frequency switch elements SW1 and SW2, respectively.

However, the high-frequency switch element SW1 and the high-frequency switch element SW2 may be integrated as one high-frequency semiconductor integrated circuit element as shown in FIG.
Further, a multi-port switch element such as SP8T may be used instead of the branching circuit and the high-frequency switch elements SW1 and SW2.
Hereinafter, description will be made assuming that the high-frequency switch element SW1 and the high-frequency switch element SW2 are integrated as one high-frequency semiconductor integrated circuit element SWIC.

FIG. 3 is a schematic sectional view of a high-frequency switching module according to the present invention, and FIG. 4 is a partially cutaway perspective view of the high-frequency switching module.
As shown in FIGS. 3 and 4, the high-frequency switching module of the present invention is formed on a multilayer substrate A in which a dielectric layer and a conductor layer are laminated.
The multilayer substrate A is configured by laminating dielectric layers 11 to 17 having the same size and shape made of ceramic or epoxy resin.

On each of the dielectric layers 11 to 17 of the multilayer substrate A, a conductor layer 21 having a predetermined pattern is formed.
The dielectric layers 11 to 17 are made of, for example, ceramics for low temperature firing, and the conductor layer 21 is made of a low resistance conductor such as copper or silver.
Such a multilayer substrate A is formed by a well-known multilayer ceramic technology. For example, a conductive paste is applied to the surface of a ceramic green sheet to form conductor patterns constituting the above-described circuits. It is formed by laminating sheets, thermocompression bonding and firing under the required pressure and temperature.

Each dielectric layer 11 to 17 is formed with via hole conductors 22 and the like necessary for constituting or connecting circuits over a plurality of layers at appropriate positions.
A large-area GND electrode 37 is formed on the lower surface of the multilayer substrate A. A signal terminal pattern is formed as an LGA (land grid array) type electrode (not shown) in a portion near the side surface of the multilayer substrate A.

On the upper surface of the multilayer substrate A, a die pad (mounting electrode) 26 for mounting the high-frequency semiconductor integrated circuit element SWIC constituting the high-frequency switch elements SW1 and SW2 is formed. As shown in FIGS. 3 and 4, the die pad 26 has a larger area than the mounting surface of the high-frequency semiconductor integrated circuit element SWIC.
The high-frequency semiconductor integrated circuit element SWIC is surface-mounted on the upper surface of the multilayer substrate A via a conductive adhesive obtained by mixing an adhesive with Ag or AuSn, or an organic resin non-conductive adhesive 47.

  In such a high-frequency switching module, a part of the duplexer DIP1, the low-pass filters LPF1 and LPF2 in the high-frequency switching module RFM1 (FIG. 1), inductors, and the like are part of chip components (lumped constant elements). In addition to being provided on the upper surface of the multilayer substrate, some of the capacitors, inductors, and the like constituting the duplexer DIP1, the low-pass filters LPF2, LPF3 are provided as conductor patterns on the upper surface or the inner layer of the multilayer substrate A.

Then, the signal terminal and the ground terminal of the high-frequency semiconductor integrated circuit element SWIC constituting the high-frequency switch elements SW1 and SW2 are connected to the duplexer DIP1, via the bonding wire 56 and the conductor layer 21 on the surface of the multilayer substrate A, The low-pass filters LPF1, LPF2, etc. are electrically connected to the substrate built-in elements.
The upper surface of the multilayer substrate A is sealed with a sealing resin 55 such as an epoxy resin.

In the structure of the embodiment of the present invention, as shown in FIG. 3, via hole conductors 27 a and 28 a penetrating the dielectric layers 11 to 13 are connected to the lower surface of the die pad 26, and the lower ends of the via hole conductors 27 a and 28 a are connected. is the inductance adjustment electrode LE of the board built capacitor Nsu adjustment electrode CE are connected. The inductance adjusting electrode LE is the via-hole conductors 27b, is connected to the GND electrode 37. Capacitor Nsu adjustment electrode CE by via-hole conductors 28b, is connected to the GND electrode 37.

The inductance adjusting electrode LE is composed of a conductive pattern 23a which are respectively formed on the dielectric layer 14 to 17, and via-hole conductors 24a penetrating the respective dielectric layers 14, 15, 16, respectively.
The conductor pattern 23a extends with a certain length along the surfaces of the dielectric layers 14-17. One end of the uppermost conductor pattern 23a is connected to the lower end of the via hole conductor 27a descending from the die pad 26, and the other end of the conductor pattern 23a is connected to the via hole conductor 24a penetrating the dielectric layer 14. The via-hole conductor 24 a is connected to one end of the conductor pattern 23 a of the next layer 15, and the other end of the conductor pattern 23 a is connected to the upper end of the via-hole conductor 24 a that penetrates the next layer 15.

In this way, the inductance adjusting electrode LE, by shaping the path of zigzag, making the inductance component. Therefore, the high-frequency current flowing from the die pad 26 to the GND electrode 37 passes through the conductor path having this inductance component.
Further, the capacitor Nsu adjustment electrode CE is composed as shown in FIG. 3, a conductor pattern 23b formed respectively on the top surface of the dielectric layer 14, a via hole conductor 24b penetrating the dielectric layer 14, 15 And the other electrode composed of a conductor pattern 23c formed on the upper surfaces of the dielectric layers 15 and 17 and a via-hole conductor 24c penetrating the dielectric layers 15 and 16, respectively.

By forming the facing surfaces between the conductor patterns 23b and 23c, the capacitor Nsu adjustment electrode CE has a capacitance component. Therefore, the high frequency current flowing from the die pad 26 to the GND electrode 37 passes through this capacitance component.
As described above, the inductance adjusting electrodes LE and the capacitor Nsu adjustment electrode CE and mounted inside the multilayer substrate A, the passage attenuation extending from the antenna terminal ANT of the high-frequency switching device to the reception terminal (RX) Frequency characteristics were measured.

Receiving frequency f is set to 1.8GHz, the inductance of the inductance adjusting electrode LE is set to two types of 1nH and 2 nH, the capacitance of the capacitor Nsu adjusting electrode CE was 2.5 pF.

As shown in Table 1, by adding an inductor: 1 nH between the high-frequency switch element and the GND electrode 37, the attenuation amount of the third harmonic contained in the received signal is 1 as compared with the case without the inductor. .3 dB can be increased.
Further, by setting the inductor to 2 nH, it is possible to further increase the attenuation amount of the third harmonic.

Moreover, the attenuation of the second harmonic can be increased by 4 dB or more by adding a capacitor: 2.5 pF.
3 and 4, it is assumed that the high frequency switch element SW1 and the high frequency switch element SW2 are integrated as one high frequency semiconductor integrated circuit element SWIC.
However, the high-frequency switch element SW1 and the high-frequency switch element SW2 is respectively integrated in a separate high-frequency semiconductor integrated circuit device, in the form of mounting each high-frequency semiconductor integrated circuit device to separate the die pad, the inductance adjusting electrode LE and the provision of the capacitor Nsu adjustment electrode CE between the respective die pads and the GND electrode 37 is effective for attenuation of harmonics.

Thus, adjusting said inductance adjusting electrodes LE and the capacitor Nsu adjustment electrode CE, by separating into a For low-pass and high-pass, an inductance component and a capacitance component, independently for each band As a result, the degree of freedom in adjusting the passing attenuation amount of the high-frequency switch element can be increased.
Although the embodiments of the present invention have been described above, the embodiments of the present invention are not limited to the above-described embodiments, and various modifications can be made within the scope of the present invention.

It is a block diagram which shows an example of the high frequency switching module which concerns on this invention. It is a block diagram which shows another example of the high frequency switching module which concerns on this invention. It is a schematic sectional drawing of the high frequency switching module which concerns on this invention. It is a partially cutaway perspective view showing the internal structure of the high-frequency switching module according to the present invention. It is a block diagram which shows the conventional high frequency circuit part of the dual band system of a GSM / DCS system. It is a circuit diagram of a PIN diode switch used in a conventional dual band system.

Explanation of symbols

11-17 Dielectric layers 23a, b, c Conductor patterns 24a, b, c Via-hole conductor 26 Die pad (mounting electrode)
27a, b, a, b via-hole conductors 37 GND electrode A multilayer substrate ANT antenna terminal CE capacitor Nsu adjustment electrode DIP1 branching circuit LE inductance adjusting electrodes LPF1, LPF2 low-pass filter circuit RX receives the signal terminal SW1 high frequency switch Element SW2 High-frequency switch element SWIC High-frequency semiconductor integrated circuit element TX Transmission signal terminal

Claims (3)

A dielectric multilayer substrate comprising a plurality of dielectric layers;
A high frequency switch element mounting electrodes provided on the surface of the dielectric multilayer substrate,
The high-frequency switch element mounted on the mounting electrode, and the high frequency switch device for switching a plurality of different transmitting and receiving signals pass band by the transmission signal or reception signal transceiver system,
Said dielectric is provided et been on or within the multilayer substrate, and a filter circuit for attenuating harmonics of the transmission signal by being connected to terminals of the high-frequency switch element,
The high-frequency switch element comprises a semiconductor integrated circuit element,
The penetrating one or more dielectric layers comprises a first conductive pattern for connecting the first via hole conductors each other of the plurality of first via-hole conductors and said plurality of said high-frequency switch device mounting electrode and the front Symbol dielectric multilayer with Louis inductor Nsu adjustment electrodes to connect between the ground electrodes provided on the back surface of the substrate is provided inside the dielectric multi-layer substrate,
A second via-hole conductor connected to the high-frequency switch element mounting electrode and penetrating one or more layers of the dielectric layer; a second conductor pattern connected to the second via-hole conductor; and the grounding electrode. A third via-hole conductor connected through one or more layers of the dielectric layer, and a third via-hole connected to the third via-hole conductor and facing the second conductor pattern via the dielectric layer A high-frequency switching module comprising a conductor pattern, and a capacitance adjusting electrode which forms a capacitance between the high-frequency switch element mounting electrode and the grounding electrode is provided inside the dielectric multilayer substrate . The high-frequency switch element is provided two kinds of a high and a low frequency,
Wherein is provided with two corresponding high frequency switch device mounting electrodes for the radio frequency switching elements,
High-frequency switching module according to the each radio frequency switching device mounting electrodes, according to claim 1, each said inductance adjusting electrodes and the capacitance adjusting electrode is provided. Wireless communication device comprising a high-frequency switching module according to claim 1 or claim 2.

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