JP3694067B2 - Antenna switch with surface mount parts - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an antenna switch that can be used in the field of wireless devices such as mobile phones and automobile phones, or other various communication devices, and more particularly to an antenna switch that uses a multilayer substrate and is made into an SMD (surface mount component).
[0002]
[Prior art]
FIG. 7 is an explanatory diagram of a conventional example, and shows a circuit of a general antenna switch with antenna switching. In the figure, C40 to C43, C50 to C53 and C60 to C62 are capacitors, L40, L50 and L60 are coils, DA1, DA2, DB1 and DB2 are PIN diodes, SL41 and SL42 are striplines, Vb1 and Vb2 are PIN diodes. A power supply terminal for bias current to be turned off / off, TX is a transmission terminal, RX is a reception terminal, ANT1 is a terminal connected to the first antenna, and ANT2 is a terminal connected to the second antenna.
[0003]
First, the basic operation will be described by taking the transmission / reception switching unit as an example. In the antenna switch as described above, when a bias current is input from the power supply terminal Vb1, the PIN diodes of DA1 and DA2 are turned on, and both ends of the PIN diode are resistances. Very small conductive state. At this time, since the side of the strip line SL41 to which the PIN diode DA2 is connected is grounded, if the length is set to ¼ wavelength of the signal input from the transmission terminal TX, the PIN diode of the strip line SL41 At the DA1 side end, the input impedance becomes infinite due to the 1/4 wavelength resonance of the stripline SL41. Therefore, the signal input from the transmission terminal TX passes through the PIN diode D1, and almost flows to the capacitor C42 side. Signal leakage from the transmission terminal TX to the reception terminal RX at this time is called isolation. On the other hand, when the bias current from the power supply terminal Vb1 is cut off, the PIN diodes DA1 and DA2 are turned off, and the resistances at both ends of the PIN diode become infinite. At this time, the transmission terminal TX side is insulated from the capacitor C42 side by the PIN diode DA1, but the reception terminal RX side is input from the capacitor C42 side because the capacitor C43 and the stripline SL41 are in a conductive state by turning off the PIN diode DA2. Most of the received signals flow to the receiving terminal RX.
[0004]
In general, since transmission power is much larger than reception power, isolation is important between the transmission terminal TX and the reception terminal RX at the time of transmission, but it is not necessary to place much importance on reception.
[0005]
Since the above operation is the same in the antenna switching unit, the description is omitted.
[0006]
[Problems to be solved by the invention]
The conventional ones as described above have the following problems.
(1) The above antenna switch using a stripline resonator needs to form a stripline resonator having a length that is ¼ of the wavelength for the frequency to be used. Since two stripline resonators are required, it is difficult to reduce the size when designing a small SMD antenna switch.
[0007]
(2) When designing the antenna switch by incorporating components in a multilayer board, it is necessary to reduce the number of constituent elements as much as possible. This is because it is easy to secure the pattern area when the design is advanced with the element built in the board, and the trial characteristics are repeated by making several conditions on the constants of each element and driving to the target characteristics. Thus, the large number of elements to be changed is a burden for advancing the design quickly. However, although the circuit of FIG. 3 is calculated by optimizing the characteristics of the antenna switch by a computer, it cannot be said that the number of constituent elements is small.
[0008]
(3) When the above antenna switch using a stripline resonator is designed with a multilayer substrate, the stripline resonator needs to be housed in the substrate and is usually a triplate type sandwiched between GND (ground) electrodes. Although a stripline resonator is used, in order to ensure the Q and line impedance of the resonator, it is necessary to set the distance between the GND electrode and the stripline large to some extent. Therefore, it tends to be thick as a substrate. This means that when the substrate is designed with ceramic, the debinding property is deteriorated at the time of firing, and it is difficult to individually divide the original substrate at the time of manufacture into a substrate shape as a component.
[0009]
It is an object of the present invention to provide two systems of switch circuits with symmetry so as to reduce the types of constituent elements, and to achieve sufficient isolation with a small size, a thin shape, low insertion loss.
[0010]
[Means for Solving the Problems]
1 and FIG. 2 are diagrams for explaining the principle of the present invention. FIG. 1A is a circuit configuration diagram, FIG. 1B is an example of a multilayer substrate pattern configuration, and FIG. 1C is an equivalent of a switch circuit configuration example. The circuit, A in FIG. 2, is a cross-sectional view of the antenna switch. In the figure, 20 is a multilayer substrate, 22 is a GND electrode pattern, 21 is an external connection electrode, the filter stage is a low-pass filter (LPF) stage, XY is a line passing through the center of the LPF stage, C10 to C13 are capacitors, L10 L12 is a coil, D1 and D2 are PIN diodes, a is a terminal connected to the transmission input or the antenna 2, c is a terminal connected to the receiving side or the antenna 1, and e is connected to an LPF (low-pass filter) stage via a capacitor. Indicates a terminal.
[0011]
In order to achieve the above object, the present invention is configured as follows.
[0012]
(1) : A surface mount component including at least a plurality of switch circuits and a filter stage of a first switch circuit and a second switch circuit for switching a signal by turning on / off a current flowing through the PIN diodes D1 and D2. PIN diodes D1 and D2 are mounted on a multilayer substrate, which is an antenna switch, and at least a part of each of the passive elements forming the circuit and the filter stage is patterned. A grounding capacitor portion composed of an electrode opposed to the formed grounding conductor, a spacer portion having a layer whose distance is longer than that between the grounding capacitor electrodes and having no pattern electrode formed in a plane direction, a coil electrode pattern and a capacitor electrode pattern Consists of a capacitor and a coil forming part.
(2) In the antenna switch formed as a surface mount component according to ( 1 ) above, the dielectric material constituting the multilayer substrate is a ceramic material, and the thickness of the multilayer substrate after firing is 1.5 mm or less.
[0013]
(3) In the antenna switch formed as a surface mount component according to ( 1 ) or ( 2 ), the coil avoids overlapping with electrodes for mounting PIN diodes D1 and D2 formed on the surface of the multilayer substrate. Form.
(4) : In the antenna switch formed as a surface mount component according to ( 1 ) to ( 3 ), the two stages of the switch circuit and the filter stage are connected to the filter stage after the first switch circuit, A second switch circuit having the same configuration as that of the first switch circuit is connected to the subsequent stage.
[0014]
(5) In the antenna switch formed as a surface mount component according to (1) to ( 4 ) above, the patterning of each layer of the multilayer substrate of the first switch circuit and the second switch circuit is performed on the filter stage. Make symmetrical.
(6) : In the antenna switch formed as a surface mount component according to (1) to ( 5 ), the first switch circuit and the second switch circuit include a first PIN diode D1 close to the control power supply terminal Vb. An inductance element L11 connected between the second PIN diode D2 and the second PIN diode D2 is provided, and the PIN diode is turned on / off by the control power supply of the control power supply terminal Vb to switch between transmission and reception.
[0015]
(7) : In the antenna switch formed as a surface-mount component according to ( 6 ), an impedance correcting capacitive element C13 is connected in parallel to the inductance element L11.
[0016]
(Function)
Since this configuration is configured as described above, it has the following effects.
In the antenna switch with antenna switching, when an LPF stage is added, as shown in FIG. 7, even if the circuit is optimized in the direction of reducing the number of constituent elements, a considerable number of elements are configured.
[0017]
In most cellular phone systems, the transmission frequency and the reception frequency are set to different frequencies. Therefore, when designing an antenna switch that performs transmission / reception switching and antenna switching under the system, the transmission / reception switching unit should optimize the characteristics of the transmitting end side and the receiving end side to the respective frequencies of the transmission band and the reception band. Good characteristics can be obtained. On the other hand, the antenna switching side needs to be designed well for both transmission and reception frequency bands.
[0018]
Based on the above, it was thought that the constants of the constituent elements of the transmission / reception switching unit circuit and the antenna switching unit circuit should be set so that their respective features can be obtained. Therefore, different constants as shown in FIG. 7 are likely to be set. It was.
[0019]
Therefore, in the present invention, a configuration for reducing the types of constants of the constituent elements has been studied. Conventionally, in order to cut the bias current of the PIN diode between the switch circuits, one capacitor is inserted in series in the signal line between the first switch circuit and the second switch circuit, and an LPF stage is further inserted. However, it has been found that the constants of the corresponding constituent elements of each switch circuit can be designed to be exactly the same by inserting capacitors on both sides of the LPF stage in series with the signal line.
[0020]
As a result, the number of constituent elements is increased by one compared to the conventional design, but the number of types of constituent elements is reduced to about half.
Furthermore, when designing an antenna switch with antenna switching with the above configuration using a multilayer substrate, the configuration and constant values of each switch circuit are exactly the same, so it is possible to design utilizing the sameness within the multilayer substrate Become. That is, as shown in FIG. 1B, the LPF stage is set near the center of the substrate (although slightly biased to one end of the substrate), and the XY line passing through the center of the LPF stage is symmetrical. In addition, it is possible to pattern the constituent elements of each switch circuit.
[0021]
As a result, it becomes easier to set the conditions of each element with respect to the pursuit of the target characteristic, and it becomes relatively easy to solve the problem in the pattern design. That is, conventionally, countermeasures have been taken individually for places where problems are likely to occur.However, in the present invention, another place can be taken simultaneously by using symmetry, so that it is easy to find the problematic places. Become.
[0022]
Further, as for the input impedance of each terminal a, b, c, d, since the transmission terminal a and the connection terminal b of the antenna 2 and the reception terminal c and the connection terminal d of the antenna 1 have the same input impedance, Compared to the conventional configuration in which the input impedance of the terminals is different, the characteristic evaluation itself is easier.
[0023]
On the other hand, although there are various switch circuits, the circuit shown in FIG. This will be described here. First, the coil increases its impedance linearly with respect to the normal frequency. (Z = ωL Z: impedance, ω: angular frequency, L: inductance of the coil) However, in the high frequency band, the impedance increases nonlinearly with respect to the frequency due to the stray capacitance of the coil itself, resulting in self-resonance. Therefore, the stray capacitance of the coil cannot be ignored in the high frequency band. Therefore, in the present invention, the circuit calculation is performed by adding a capacitor C13 in parallel to the coil L11 inserted between the PIN diodes D1 and D2 in order to include the stray capacitance.
[0024]
In performing the circuit calculation, the frequency characteristic of the PIN diode is measured in advance as an S parameter, and the result is substituted into the transmission equation of the equivalent circuit of C in FIG. 1, and the optimum capacitor and coil constants are obtained. A constant that can minimize the insertion loss in the signal passband (between ae and ec terminals) in the equivalent circuit of C, and ensure isolation between a and c when the PIN diode is ON is 20 dB or more. I found that there was a combination.
[0025]
At this time, the capacitance value of the capacitor C13 is somewhat larger than the stray capacitance of the coil L11, and the parallel resonance frequency of the coil L11 and the capacitor C13 does not become a frequency near the transmission and reception frequencies. Therefore, it is considered that the isolation is not expressed by a resonance phenomenon as in the case of using a stripline resonator.
[0026]
On the other hand, since an antenna switch can be configured with a capacitor and a coil without using a stripline resonator, a passive element is patterned on a plurality of dielectric sheets, and a multilayer substrate obtained by laminating them is formed as shown in FIG. If the antenna switch is configured using the equivalent circuit, it is preferable to reduce the size of the antenna switch.
[0027]
FIG. 2A shows a schematic cross-sectional view when an antenna switch is configured with a multilayer substrate. As shown in this figure, the multilayer substrate 20 has a GND electrode pattern 22 formed on almost the entire surface of the lower layer in the stacking direction, and a grounding capacitor counter electrode formed on the upper layer. Thus, the grounding capacitor portion is formed. Thereby, it becomes a structure which is hard to receive the electrical influence from the motherboard which mounts an antenna switch.
[0028]
Furthermore, a spacer part with almost no pattern is set on the upper side of the grounding capacitor part, and a capacitor and a coil forming part for patterning by mixing capacitors and coils other than the grounding capacitor are set on the upper side of the spacer part. To do. Thereby, the patterned capacitor | condenser and coil can reduce the stray capacitance with respect to GND. In particular, the coil tends to deteriorate if the electrode pattern is close to the coil in the stacking direction. This causes deterioration of insertion loss and reduction of isolation. It is even better to perform patterning at a position deviated from the electrode for use.
[0029]
With such a configuration, the space utilization in the substrate is increased as compared with the design in which the strip line is built in the substrate, and the thickness of the spacer portion is a triplate type strip line in which the strip line is sandwiched between the GND electrodes. It can be set depending on the characteristics of the antenna switch from the thickness of the spacer portion, which is about the distance between the GND electrode and the strip line when set by the resonator. Therefore, compared to the thickness of the substrate of the antenna switch using the triplate type stripline resonator, the thickness of the substrate having the above configuration can be designed to be approximately half the thickness.
[0030]
Therefore, it is possible to reduce the size by the configuration of the multilayer substrate, and it is possible to design an antenna switch having a substrate thickness thinner than that of the conventional design and having a low insertion loss and sufficient isolation.
[0031]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings.
3 to 6 show an embodiment of the present invention, and the same components as those in FIGS. 1 and 2 are denoted by the same reference numerals.
[0032]
FIG. 3 is a circuit diagram of the antenna switch. In FIG. 3, C20A to C24A and C20B to C24B are capacitors, L20A to L22A, and L20B to L22B are coils, and D1A, D2A, D1B, and D2B are PIN diodes. Components having the same reference numerals other than A and B at the end of the capacitor and coil are set to the same constant. That is, C20A = C20B and L20A = L20B,. Further, C31 and C32 in the LPF (low-pass filter) stage have a relationship of C31 = C32.
[0033]
The circuit of this embodiment is an antenna switch used in the vicinity of about 1 GHz, and coils L22A and L22B are added to improve the insertion loss between ANT (antenna) 1-RX and ANAT2-RX. Since the constant was about several nH, the coil L22A and L22B were used as they were because there was no significant influence on calculation even if the stray capacitance of the frequency band was ignored to some extent in the frequency band. Further, the capacitance values of the capacitors C24A and C24B were calculated by previously measuring the stray capacitance of the coils L22A and L22B by measuring the self-resonance frequency, and set the capacitance value by subtracting that value.
[0034]
4 is an exploded perspective view of the antenna switch (part 1), FIG. 5 is an exploded perspective view of the antenna switch (part 2), FIG. 6A is a diode package, and FIG. 6B is a completed antenna switch. Show. In FIG. 6B, 1A is a TX terminal (transmission terminal), 2A, 2B, 5A, 5B, 6A, 6B are GND terminals (grounding terminals), 3A is a Vb1 terminal (transmission / reception switching bias current terminal), and 3B is a Vb2 terminal. (Antenna switching bias current terminal) 1B is an ANT2 terminal (terminal connected to the antenna 2), 4B is an ANT1 terminal (terminal connected to the antenna 1), and 4A is an RX terminal (receiving terminal). In addition, the PIN diode used in this example uses the SMD component of the package shown in FIG. Therefore, the anode of the PIN diode D1A is connected to the electrode 501A for the mounting component, the cathode of the PIN diode D1A is connected to the electrode 502A for the mounting component, and the anode of the PIN diode D2A is connected to the electrode 503A for the mounting component. The cathode of the PIN diode D2A is connected to the electrode 504A. On the other hand, the anode of the PIN diode D1B is connected to the electrode 501B for the mounting component, the cathode of the PIN diode D1B is connected to the electrode 502B for the mounting component, and the anode of the PIN diode D2B is connected to the electrode 503B for the mounting component. The cathode of the PIN diode D2B is connected to the electrode 504B.
[0035]
In the exploded perspective view of FIG. 4, the line XY is a line that substantially indicates the center with respect to the length of the substrate in the orthogonal direction. The electrode having the description of A and B at the end of each symbol indicates that the electrode is arranged symmetrically with respect to the XY line. That is, the electrodes 221A and 221B, 420A and 420B, 11A and 11B,... Are arranged symmetrically with respect to the line XY. Therefore, if the conductor pattern with A (transmission / reception switching unit) is described, if the symbol is replaced with B as it is, the conductor pattern with B (antenna switching unit) will be described. The (transmission / reception switching unit) will be described in detail, and the conductor pattern with B (antenna switching unit) will be omitted.
[0036]
4 and 5, reference numerals 20-1 to 20-8 denote the first to eighth layers (dielectric layers) of the multilayer substrate 20. First, the electrode 211A and the electrode 212A are opposed to each other via the second layer 20-2 to form a capacitor C21A, and the electrode 211 is connected to the mounting component electrode 501A by the through-hole electrode 11A and is connected to the anode side of the PIN diode D1A. Connecting. On the other hand, the electrode 212A is drawn to the end of the multilayer substrate by the electrode 210A and connected to the external connection electrode 1A. The electrode 401A extending from the electrode 211A is connected to the electrode 402A by the through-hole electrode 15A, and further connected to the electrode 403A by the through-hole electrode 22A to form a coil L20A. The coil L20A is drawn to the end of the multilayer substrate by the electrode 400A and connected to the external connection electrode 3A.
[0037]
The capacitor C22A connected to the cathode of the PIN diode D1A is formed such that the electrode 221A and the electrode 222A are opposed to each other with the second layer 20-2 interposed therebetween, but the electrode 221A from the mounting component electrode 502A through the through-hole electrode 12A. Connected to. Further, the through-hole electrode 12A reaches the third layer 20-3, is connected to the electrode 412A, and reaches the electrode 413A on the fourth layer 20-4 by the through-hole electrode 20A connected to the electrode 412A. The electrode 413A is connected to one electrode 242A of the capacitor C24A through the through-hole electrode 21A. The electrode 412A is connected to the electrode 411A on the second layer 20-2 by the through-hole electrode 16A connected on the third layer 20-3, and the coil L21A is constituted by the electrodes 411A, 16A, and 412A. ing. The electrode 41A of the coil L21A is connected to the other electrode 241A of the capacitor C24A via the electrode 231A. In the capacitor C24A, the electrode 242A and the electrode 241A are formed to face each other via the second layer 20-2. With this configuration, L21A and C24A are connected in parallel.
[0038]
Further, the electrode 231A connected to 411A forms a capacitor C23A with the electrode 232A opposed via the second layer 20-2. Further, the electrode 231A is connected to the component mounting electrode 503A (not visible in the figure behind the component) by the through-hole electrode 13A, and the component mounting electrode 503A is connected to the anode of the PIN diode D2APIN diode D2A. . One electrode 232A of the capacitor C23A is connected to the electrode 422A, and the electrode 422A is connected to the electrode 421A on the second layer 20-2 by the through-hole electrode 17A, thereby forming a coil L22A. The coil L22A is drawn to the end of the multilayer substrate by the electrode 420A and connected to the external connection electrode 4A. Further, the cathode side of the PIN diode D2A is connected to the component mounting electrode 504A, and is connected to the electrode 300A on the second layer 20-2 via the through-hole electrode 14A. Connect to the GND terminal of the electrode 6A.
[0039]
The dielectric layers of the fourth layer 20-4, the fifth layer 20-5, and the sixth layer 20-6 are used as a spacer portion. The electrode 201A on the seventh layer is an electrode on the side other than the GND (ground) of the ground capacitor C20A, and the ground capacitor C20A is formed from the GND (ground) electrode 22 facing through the seventh layer 20-7. The electrode 201A of the ground capacitor C20A is drawn to the end of the multilayer substrate by the electrode 200A and connected to the external connection electrode 3A.
[0040]
The eighth layer 20-8 has a GND electrode formed on substantially the entire surface of the dielectric. These GND electrodes 22 are led out to the end of the multilayer substrate by the electrodes 22-1A, 22-2A, and 22-3A and connected to the GND terminals of the external connection electrodes 2A, 6A, and 5A, respectively.
[0041]
This completes the description of the conductor pattern with A (transmission / reception switching unit).
Next, the LPF stage will be described. In the LPF stage, one electrode 222A of the capacitor CC22A of the transmission / reception switching unit is an input / output unit. The electrode 222A on the third layer 20-3 is connected to the electrode 312, and the electrode 312 forms the capacitor C31 with the electrode 311 on the second layer 20-2 facing each other through the second layer 20-2. The capacitor C31 is connected to the electrode 300A on the electrode 311 side and led to the end of the multilayer substrate, and is connected to the GND terminal of the external connection electrode 6A.
[0042]
The electrode 312 on the third layer 20-3 is connected to the electrode 602, and this electrode 602 is connected to the through-hole electrode 18 and connected to the electrode 601 on the second layer 20-2. These electrodes 602, 18 and 601 constitute a coil L30. Further, both ends of the coil L30 are connected to the electrode 302 by the electrode 602 on the third layer 20-3 and to the electrode 301 by the electrode 601 on the second layer 20-2, and the electrodes 302 and 301 are connected to the second layer. A capacitor C30 is formed so as to face each other through 20-2. As a result, the capacitor C30 and the coil L30 are connected in parallel.
[0043]
Furthermore, the electrode 601 on the second layer is connected to the electrode 322 on the third layer 20-3 by the through-hole electrode 19. The electrode 322 constitutes a capacitor C32 with the electrode 321 on the second layer 20-2 facing each other through the second layer 20-2. In the capacitor C32, one electrode 321 on the second layer 20-2 is led to the end of the multilayer substrate by the electrode 300B, and is connected to the GND electrode of the external connection electrode 6B. The electrode 322 is connected to one electrode 222B of the capacitor C22B serving as an antenna switching circuit side input / output unit. The above is the pattern configuration of the LPF stage.
[0044]
In this embodiment, the surfaces of the second layer, the third layer, and the fourth layer are the capacitor and coil forming portions, the fourth dielectric layer and the fifth and sixth layers are the spacer portions, and the seventh and eighth layers. The surface is a grounding capacitor. Regarding the patterning of the coil, particularly in the capacitor and coil forming part, it is better to pattern the coil by avoiding the part overlapping the mounting part electrodes (501A, 502A, 503A, 504A, 501B, 502B, 503B, 504B) on the substrate surface as much as possible. Does not deteriorate. Also, multiple coils formed on the substrate are prone to stray coupling if they are too close to each other, so it is necessary to separate them as much as possible or to form a capacitor between the coils to make stray coupling difficult to occur. There is. In particular, the method of forming a capacitor between coils is a very effective method for producing a shielding effect between coils and effectively utilizing a narrow area.
[0045]
The thicker the spacer, the better the characteristics for capacitors and coils that are not grounded.For example, when this configuration is made of ceramic, it has a debinding property during firing and a substrate shape as a component during manufacturing. Therefore, a method of dividing the original substrate separately is a problem. Therefore, as a guideline, the thickness of the spacer portion is adjusted so that the entire substrate thickness is about 1.5 mm or less (in the case of ceramic, the thickness of the substrate after firing).
[0046]
In addition, the circuit of the filter stage is preferably a symmetrical circuit in the input / output section of the filter stage.
[0047]
【The invention's effect】
As described above, the present invention has the following effects.
(1) Since the number of component elements in the multilayer substrate is about half that of the conventional one, the number of combinations of element constant conditions can be reduced in pursuing the target characteristics, so that development can be promoted quickly.
[0048]
(2) Since the patterning of the constituent elements in the multilayer substrate is set taking advantage of symmetry, it becomes easy to find and take measures against patterning problems.
(3) Regarding the input impedance of each terminal, the input impedance of each terminal was different in the past, but due to the symmetry of the circuit, two of the terminals have the same input impedance, making it easier to evaluate the characteristics. .
[0049]
(4) the amount antenna switch that does not use a strip line can be designed compact.
(5) When a ceramic multilayer substrate is used, the substrate thickness can be designed to be thin, so that the binder removal property during firing is good, and individual division can be easily performed into the substrate shape as a component from the original substrate during manufacturing. .
[0050]
(6) An antenna switch with sufficient isolation can be obtained with a low insertion loss even when a multilayer board is used and the board thickness is reduced.
[Brief description of the drawings]
FIG. 1 is a diagram for explaining the principle of the present invention (part 1);
FIG. 2 is a diagram for explaining the principle of the present invention (part 2);
FIG. 3 is a circuit diagram of an antenna switch in the embodiment.
FIG. 4 is an exploded perspective view (No. 1) of the antenna switch in the embodiment.
FIG. 5 is an exploded perspective view (No. 2) of the antenna switch in the embodiment.
6A is a diagram of a diode package, and B is a diagram of a completed antenna switch. FIG.
FIG. 7 is an explanatory diagram of a conventional example.
[Explanation of symbols]
20 Multilayer Substrate 21 External Connection Electrode 22 GND Electrode ANT1 Terminal 1 Connected to Antenna 1 ANT2 Terminal Connected to Antenna 2 TX Transmission Terminal RX Reception Terminal

Claims (7)

An antenna switch that is a surface-mount component including at least a plurality of switch circuits of a first switch circuit and a second switch circuit that switch a signal by turning on / off a current flowing through a PIN diode and a filter stage,
A PIN diode is mounted on a multilayer substrate in which at least a part of each of the passive elements forming the circuit and the filter stage is patterned,
The multilayer substrate comprises a grounding capacitor portion composed of an electrode facing a grounding conductor formed on almost the entire surface in order from the mounting surface;
A spacer part having a layer whose distance is longer than that between the grounded capacitor electrodes and having no pattern electrode formed in the plane direction;
An antenna switch formed as a surface mount component, comprising a capacitor and a coil forming portion in which a coil electrode pattern and a capacitor electrode pattern are mixed. It said dielectric constituting the multilayer substrate is a ceramic material, the antenna switch and the surface mount components of claim 1, wherein the thickness after firing of the multilayer substrate is 1.5mm or less. The antenna switch according to claim 1 or 2 , wherein the coil is formed so as not to overlap with an electrode for mounting a PIN diode formed on the surface of the multilayer substrate. The two switch circuits and the filter stage are configured such that the filter stage is connected to the subsequent stage of the first switch circuit, and the second switch circuit having the same configuration as the first switch circuit is connected to the subsequent stage. antenna switch with surface mount components of according to any one of claims 1 to 3. Said first switch circuit and patterning of each layer of the multilayer substrate of the second switch circuit surface mounted part according to any one of claims 1 to 4, characterized in that symmetrically with respect to said filter stage Antenna switch. The first switch circuit and the second switch circuit each include an inductance element connected between a first PIN diode close to a control power supply terminal and a second PIN diode following the first PIN diode, and the control power supply terminal antenna switch with surface mount components of according to any one of claims 1 to 5 the PIN diode by controlling power on / off control to characterized in that it is a configuration in which switching between transmission and reception. 7. The antenna switch according to claim 6 , wherein a capacitance element for impedance correction is connected in parallel to the inductance element.

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