JP2007049717A - Composite switch circuit component - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact composite switch circuit component with excellent characteristics. <P>SOLUTION: The component is configured such that a switch circuit and a low-pass filter circuit are constructed from a semiconductor element packaged on a laminate and an electrode pattern formed on a dielectric layer of the laminate. The low-pass filter circuit comprises a ground capacitor, an inductor, and a capacitor comprising a parallel resonance circuit together with the inductor. A ground electrode is included on the dielectric layer of the laminate and when a mounting surface of the laminate is a bottom surface and a surface for packaging the semiconductor element thereon is an upper surface, a capacitor electrode for the ground capacitor is disposed upside the ground electrode via the dielectric layer. Further on an upper side thereof, a capacitor electrode for the parallel resonance circuit is disposed to face the capacitor electrode for the ground capacitor via the dielectric layer. Further on an upper side thereof, a coil electrode constituting the inductor is disposed via the dielectric layer. One terminal of the coil electrode is connected with the capacitor electrode for the parallel resonance circuit and the semiconductor element via a through-hole electrode. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a switch circuit, and more particularly to a diode switch applied to a high-frequency switch circuit for switching a signal transmission path in a high-frequency circuit such as a digital cellular phone.

  For example, a switch circuit such as a digital cellular phone is used to switch a transmission path between an antenna and a reception circuit and a transmission path between a transmission circuit and an antenna.

  This switch circuit is also used to switch the transmission path between the reception circuit and the first antenna and the transmission path between the reception circuit and the second antenna in a telephone or the like adopting the reception diversity system. The Similarly, in the case of a mobile phone base station adopting the transmission diversity system, it is used to switch the transmission path between the transmission circuit and the first antenna and the transmission path between the transmission circuit and the second antenna. Is done.

  In addition, this switch circuit is used for switching between internal circuits such as a mobile phone having a terminal for external connection with an in-vehicle booster or the like and a route to the above terminal, and switching of a plurality of channels such as a base station for a mobile phone. Is also used.

  As a conventional switch circuit, there is one disclosed in JP-A-6-197040. A circuit diagram of this conventional example is shown in FIG. This switch circuit is connected to the antenna ANT, the transmission circuit TX, and the reception circuit RX. The transmitter circuit TX is connected to the anode of the first diode D101 via the first capacitor C101, and the cathode of the first diode D101 is connected to the antenna ANT via the third capacitor C103.

  The antenna ANT is connected to the receiving circuit RX through a series circuit of the third capacitor C103, the second transmission line SL2, and the fourth capacitor C104. The anode of the first diode D1 is grounded via a series circuit of the first transmission line SL1 and the second capacitor C102. Further, a control circuit T1 is connected between the first transmission line SL1 and the second capacitor C102 via a resistor R101. The anode of the second diode D102 is connected between the second transmission line SL2 and the fourth capacitor C104, and the cathode of the second diode D102 is grounded.

  The transmission line and the capacitor are formed in the laminated body, and a diode, a capacitor, and a resistor are mounted on the laminated body.

  When a filter component is connected to the switch circuit, the switch circuit and the filter circuit are separated and combined. For this reason, there is a problem that a mounting area is large and an impedance matching circuit has to be added.

  On the other hand, Japanese Patent Application Laid-Open No. 8-97743 proposes a component that combines a switch circuit and a filter circuit. An equivalent circuit diagram of this conventional example is shown in FIG.

  In the case of this conventional example, a portion surrounded by a broken line is a low-pass filter circuit, but a five-stage low-pass filter circuit is used. As an important characteristic of the low-pass filter, there are attenuation amounts of 2f and 3f (f is a pass frequency). In order to obtain the attenuation amounts of 2f and 3f, a five-stage low-pass filter circuit configuration is used. For this reason, there was a limit to miniaturization.

  An object of the present invention is to solve the above-described problems and provide a small composite switch circuit component having good characteristics.

  The present invention provides a composite switch circuit component in which a switch circuit and a low-pass filter circuit are configured by a semiconductor element mounted on a multilayer body and an electrode pattern formed on a dielectric layer of the multilayer body, and the low-pass filter circuit Comprises a grounding capacitor, an inductor, and a capacitor constituting a parallel resonant circuit with the inductor, the dielectric layer of the multilayer body has a ground electrode, the mounting surface of the multilayer body is a bottom surface, and the semiconductor element is When the mounting surface is the upper surface, the capacitor electrode for the ground capacitor is disposed above the ground electrode via a dielectric layer, and further on the upper side, the capacitor electrode for the parallel resonant circuit is dielectrically connected. It is arranged to face the capacitor electrode for the grounding capacitor through a body layer, and further, on the upper side, a coil electrode that constitutes the inductor is a dielectric. Is disposed over the layer, one end of the coil electrode, the the capacitor electrodes for the parallel resonance circuit and the semiconductor element, a composite switch circuit component, characterized in that it is connected via a through hole electrode.

  In the present invention, the switch circuit includes a first diode connected between the transmission circuit and the antenna, a transmission line connected between the antenna and the reception circuit, and the reception circuit and the ground. It is preferable to include a second diode to be connected and a grounding capacitor connected between the second diode and ground.

  According to the present invention, it is possible to constitute a composite switch circuit which is a switch circuit incorporating a low-pass filter circuit and which is small in size and excellent in characteristics. In addition, a transmission line and a low-pass filter circuit can be formed in a laminated body of dielectric layers to constitute a small composite switch circuit component.

  In the present invention, the switch circuit and the low-pass filter circuit are formed as a single component, and a small composite switch circuit component is configured by a laminated structure. In addition, in the present invention, in the laminated structure, the switch circuit portion is disposed below the mounting surface of the composite switch circuit component, and the low-pass filter circuit portion is disposed above.

  In the present invention, the transmission line for the switch circuit and the ground capacitor are sandwiched from above and below by the ground electrode, and the conductive pattern of the capacitor for the low-pass filter circuit is formed further above the ground electrode on the upper side. With this structure, a composite switch circuit component having a small size and good characteristics can be obtained.

  Hereinafter, the present invention will be described in detail according to examples. A perspective view of an embodiment according to the present invention is shown in FIG. Further, FIG. 2 shows an exploded perspective view of this embodiment, and FIG. 3 shows an equivalent circuit diagram thereof. This embodiment is composed of a laminated body 2 of dielectric layers and a semiconductor element 1 in which two diodes are built. In the equivalent circuit diagram, the inside of the outer broken line is the part of this embodiment, and the capacitors C11, C12, C13, C14 and resistors R1, R2 outside the broken line are connected as external parts on a circuit board or the like. The In addition, the external component can be configured in the laminated body or on the laminated body.

  The internal structure of the laminate 2 is as shown in FIG. A first ground electrode 31 is formed on the lower dielectric layer 21, and a predetermined lead electrode is formed. And it connects to external electrode (2) (7) (8).

  On the dielectric layer 21, the dielectric layer 22 on which the capacitor electrode 41 that forms the capacitor C <b> 1 is formed opposite to the first ground electrode 31 is laminated. The capacitor electrode 41 is formed with a lead electrode. And it connects to an external electrode (4).

  On top of this, two dielectric layers 23 and 24 constituting a transmission line are laminated. The transmission line L1 in the equivalent circuit diagram is configured by connecting the line electrode 11 of the dielectric layer 23 and the line electrode 12 of the dielectric layer 24. The two line electrodes are connected through the through-hole electrode 51. Then, extraction electrodes facing the side surfaces of the respective dielectric layers are respectively formed and connected to the external electrodes (3) and (6).

  The transmission line L2 in the equivalent circuit diagram is configured by connecting the line electrode 13 of the dielectric layer 23 and the line electrode 14 of the dielectric layer 24. The connection between the two line electrodes is made through the through-hole electrode 52. And the extraction electrode which faces the side surface of each dielectric material layer is formed, respectively, and is connected to external electrode (1) (5).

  On the dielectric layer 25 thereabove, a second ground electrode 32 is formed, and a predetermined lead electrode is formed. And it connects to external electrode (2) (7) (8).

  Capacitor electrodes 42 and 43 that form capacitors C2 and C3 are formed on the dielectric layer 26 so as to face the second earth electrode 32. The capacitor electrode 42 is formed with an extraction electrode and connected to the external electrode (3).

  On the dielectric layer 27 thereabove, a capacitor electrode 44 is formed to face the capacitor electrode 42 and form a capacitor C4. The capacitor electrode 44 is formed with a through-hole electrode 53 and is connected to the lower capacitor electrode 43.

  A coil electrode 15 constituting L3 is formed on the dielectric layer 28 thereon. One end of the coil electrode 15 is connected to the external electrode (3), and the other is a through-hole electrode 54 and is connected to the lower-layer through-hole electrode 53.

  A pattern electrode is formed on the upper surface of the uppermost dielectric layer 29. One pattern electrode 16 is connected to the lower through-hole electrode 54 by a through-hole electrode 55. The pattern electrode 17 is a mark. In addition, pattern electrodes connected to the external electrodes (1), (4), (5), and (6) are formed.

  This laminate is made by using a dielectric material, forming a sheet with a doctor blade, screen-printing an Ag electrode on this sheet to form a pattern electrode, laminating it, pressing it, and firing it integrally It is. Then, terminal electrodes (1), (2), (3), (4), (5), (6), (7), and (8) on the side surfaces after firing, and pattern electrodes on the upper surface were formed. The terminals of the semiconductor element 1 incorporating two diodes are connected to the pattern electrodes 16 and (5), (1) and (4), respectively.

  The insertion loss characteristics of this example are shown in FIG. As shown in FIG. 5, according to this embodiment, a composite switch circuit component that suppresses harmonics such as 2f and 3f can be obtained.

  In this embodiment, the first transmission line and the second transmission line are arranged between the first ground electrode 31 and the second ground electrode 32. The switch circuit is disposed on the mounting surface side of the composite switch circuit component. A low-pass filter circuit is configured above the switch circuit.

  Since the low-pass filter circuit portion is arranged on the upper side of the switch circuit portion, in the capacitors C2 and C3 inserted between the grounds of the low-pass filter circuit, the conductive patterns 42 and 43 constituting the capacitance are The opposing second ground electrode 32 has a lead portion connected to the ground on the actual substrate. In this embodiment, the external electrode (2) corresponds to this. This external electrode (2) functions as a line electrode, and can be regarded as a circuit in which an inductor L is connected in series to the capacitors C2 and C3. FIG. 4 shows an equivalent circuit. Thereby, attenuation poles can be created in 2f, 3f, etc. by the parallel resonance of the capacitor C4 and the inductor L3, or the series resonance of the capacitor C2 and the inductor L4, and the series resonance of the capacitor C3 and the inductor L5. It is effective in reducing

  The transmission lines L1 and L2 are both formed in a spiral shape and are divided into two layers. By using this spiral shape and further providing an overlapping portion, the line length could be shortened.

  FIG. 6 shows an exploded perspective view of a laminate of another embodiment according to the present invention, and FIG. 7 shows an equivalent circuit diagram thereof. In FIG. 6, the same parts as those in FIG. This embodiment has substantially the same structure as the above embodiment, and a capacitor C5 connected between one end of the first transmission line L1 and the ground is connected. This is composed of a capacitor forming electrode pattern 45 formed on the second dielectric layer 22 from the bottom so as to face the first ground electrode 31 formed on the lower dielectric layer 21. Yes. Other structures are the same.

  Also in this example, the same characteristics as in the above example could be obtained. Further, the capacitor C5 portion may be connected as shown in FIG. Both the capacitor C5 of FIG. 7 and the capacitor C6 of FIG. 8 have the effect of shortening the line length of the first transmission line L1.

  According to the present invention, the switch circuit incorporating the low-pass filter circuit can be integrated and made compact. Moreover, it has excellent characteristics of low loss and high harmonic suppression effect. In the present invention, the switch circuit of the transmission circuit, the antenna, and the reception circuit has been described. Needless to say, it can be used as a switch circuit of three circuits, but can be used as a switch of other circuits. is there.

  According to the present invention, it is possible to constitute a composite switch circuit which is a switch circuit incorporating a low-pass filter circuit and which is small in size and excellent in characteristics. In addition, a transmission line and a low-pass filter circuit can be formed in a laminated body of dielectric layers to constitute a small composite switch circuit component.

It is a perspective view of one example concerning the present invention. It is a disassembled perspective view of the laminated body of the Example shown in FIG. FIG. 2 is an equivalent circuit diagram of the embodiment according to the present invention shown in FIG. 1. It is a part of equivalent circuit of the Example which concerns on this invention. It is a graph which shows the insertion loss characteristic of one Example which concerns on this invention. It is a disassembled perspective view of the laminated body of another Example which concerns on this invention. It is an equivalent circuit schematic of another Example which concerns on this invention. It is an equivalent circuit schematic of another Example which concerns on this invention. It is an equivalent circuit diagram of a conventional switch circuit. It is an equivalent circuit diagram of another conventional switch circuit.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Semiconductor element 2 Laminate body 21, 22, 23, 24, 25, 26, 27, 28, 29 Dielectric layer 31 1st earth electrode 11, 12, 13, 14, 15 Line electrodes 51, 52, 53, 54 55 Through-hole electrode 32 Second ground electrode 41, 42, 43, 44, 45 Capacitor electrode

Claims (2)

A composite switch circuit component comprising a switch element and a low-pass filter circuit, with a semiconductor element mounted on a laminate and an electrode pattern formed on a dielectric layer of the laminate,
The low-pass filter circuit includes a ground capacitor, an inductor, and a capacitor constituting a parallel resonant circuit with the inductor,
The dielectric layer of the multilayer body has a ground electrode, and when the mounting surface of the multilayer body is the bottom surface and the surface on which the semiconductor element is mounted is the top surface, the capacitor electrode for the ground capacitor is the ground electrode. Arranged on the upper side through a dielectric layer,
Furthermore, on the upper side, the capacitor electrode for the parallel resonant circuit is arranged to face the capacitor electrode for the ground capacitor via a dielectric layer,
Furthermore, on the upper side, a coil electrode constituting the inductor is arranged via a dielectric layer,
One end of the coil electrode is connected to the capacitor electrode for the parallel resonant circuit and the semiconductor element via a through-hole electrode.   The switch circuit includes a first diode connected between the transmission circuit and the antenna, a transmission line connected between the antenna and the reception circuit, and a second diode connected between the reception circuit and the ground. The composite switch circuit component according to claim 1, further comprising a ground capacitor connected between the second diode and the second diode and ground.

Images