WO2012102190A1

WO2012102190A1 - Capacitance element, method for manufacturing capacitance element, resonance circuit, communication system, wireless charging system, power supply device, and electronic instrument

Info

Publication number: WO2012102190A1
Application number: PCT/JP2012/051167
Authority: WO
Inventors: 則孝佐藤; 管野　正喜
Original assignee: ソニー株式会社
Priority date: 2011-01-27
Filing date: 2012-01-20
Publication date: 2012-08-02
Also published as: JP2012169589A

Abstract

[Problem] To provide a capacitance element with which an electrostatic capacitance can be accurately ensured, and a variable-capacitance element with which a capacitance variability ratio can be adequately ensured; and also to provide a resonance circuit, a communication system, a wireless charging system, a power supply device, and an electronic instrument in which the capacitance elements are used. [Solution] This capacitance element (variable-capacitance element (1)) is provided with a capacitance element body (2) configured from a dielectric layer (4) and at least one pair of capacitance element electrodes (5a, 5b) that sandwich the dielectric layer (4) and generate a desired electric field on the dielectric layer (4). The capacitance element is also provided with stress controllers (6, 7) for controlling stress generated in the dielectric layer (4) of the capacitance element body (2) and increasing the electrostatic capacitance of the capacitance element body (2).

Description

Capacitor element, method for manufacturing capacitor element, resonance circuit, communication system, wireless charging system, power supply device and electronic device

The present invention relates to a capacitive element and a resonance circuit including the capacitive element, and more particularly to a capacitive element capable of controlling a stress generated in the capacitive element during use and increasing a capacitance, a method of manufacturing the capacitive element, and a capacitance thereof The present invention relates to a resonant circuit using an element. In addition, the present invention relates to a communication system, a wireless charging system, a power supply device, and an electronic device using the capacitor.

In recent years, with the miniaturization and high reliability of electronic devices, development of miniaturized capacitive elements has been demanded as electronic components used in the electronic devices. Then, in order to enable a reduction in size and increase in capacitance, a multilayer ceramic capacitor in which external electrodes are formed on a multilayer dielectric element body in which dielectric layers and internal electrode layers are alternately stacked has been proposed. (Patent Document 1).

In Patent Document 1, the obtained electrostatic capacity is improved by utilizing the fact that the dielectric constant is improved by the residual stress applied as a result of the manufacturing process inside the multilayer dielectric element body constituting the multilayer ceramic capacitor. It is described. As described above, since the residual stress is eventually applied to the multilayer dielectric element body in the multilayer ceramic capacitor, the dielectric constant can be improved, so that further miniaturization is possible.

WO2005 / 050679 publication

By the way, when there is variation in capacitance for each capacitor element to be used, there is a problem that the performance of the electronic device cannot be ensured with high accuracy. For this reason, when using a capacitive element, there is a desire to match the capacitance.
In recent years, capacitive elements (variable capacitive elements) using a dielectric layer whose electrostatic capacitance changes according to the applied control voltage have been developed. The capacitance was reduced.

In view of the above points, the present disclosure provides a capacitive element that can ensure a capacitance value with high accuracy, a capacitive element that can increase capacitance by applying a control voltage, and a method for manufacturing the capacitive element. provide. In addition, a resonance circuit, a communication system, a wireless charging system, a power supply device, and an electronic device using these capacitive elements are provided.

The capacitive element of the present disclosure includes a capacitive element body that includes a dielectric layer and at least one pair of capacitive element electrodes that sandwich the dielectric layer and generate a desired electric field in the dielectric layer. Further, a stress control unit is provided for controlling the stress generated in the dielectric layer of the capacitive element body and increasing the capacitance of the capacitive element body.

In the capacitive element of the present disclosure, the stress generated in the dielectric layer of the capacitive element body can be controlled by the stress control unit, and the capacitance of the capacitive element body can be increased. Thereby, the electrostatic capacitance of the capacitive element body can be controlled.

In the method of manufacturing a capacitive element according to the present disclosure, a capacitive paste is formed by applying a conductive paste on a dielectric sheet to be a dielectric layer so as to have a desired electrode shape, and the periphery of the capacitive element electrode is embedded. Forming a dielectric material film on the dielectric sheet; In addition, the method includes a step of forming a laminated body that becomes a capacitive element body by laminating a plurality of dielectric sheets on which capacitive element electrodes are formed. In addition, there is a step of forming a capacitive element body in which a plurality of capacitive element electrodes are laminated via a dielectric layer by firing the laminate. In addition, the method includes a step of bonding the capacitor element body to a stress control unit that controls the stress generated in the dielectric layer of the capacitor element body and increases the capacitance of the capacitor element body.

According to the capacitive element manufacturing method of the present disclosure, the periphery of the capacitive element electrode is reinforced by forming the dielectric material film. As a result, when the dielectric sheet on which the capacitive element electrode is formed is laminated and fired, the thickness of the dielectric layer in the part where the capacitive element electrode is not formed is not reduced.

The resonance circuit according to the present disclosure includes a resonance capacitor and a resonance coil connected to the resonance capacitor. The resonant capacitor includes a capacitive element body including a dielectric layer and at least one pair of capacitive element electrodes that sandwich the dielectric layer and generate a desired electric field in the dielectric layer. The resonant capacitor includes a stress control unit that controls the stress generated in the dielectric layer of the capacitive element body and increases the capacitance of the capacitive element body.

The communication system according to the present disclosure includes a transmission device and a reception device. The transmission device includes a first resonance capacitor and a first resonance coil connected to the first resonance capacitor. The first resonance coil includes a first capacitor composed of a first dielectric layer and at least one pair of first capacitive element electrodes that sandwich the first dielectric layer and generate a desired electric field in the first dielectric layer. An element body is provided. Furthermore, a first stress control unit is provided that controls the stress generated in the first dielectric layer of the first capacitive element body and increases the capacitance of the first capacitive element body. The receiving device includes a second resonance capacitor and a second resonance coil connected to the second resonance capacitor. The second resonance coil includes a second capacitor composed of at least one pair of second capacitor elements that sandwich the second dielectric layer and the second dielectric layer and generate a desired electric field in the second dielectric layer. An element body is provided. Further, a second stress control unit is provided for controlling the stress generated in the second dielectric layer of the second capacitive element body and increasing the capacitance of the second capacitive element body.

The wireless charging system of the present disclosure includes a power feeding device and a power receiving device. The power feeding device includes a first resonance capacitor and a first resonance coil connected to the first resonance capacitor. The first resonance coil includes a first capacitor composed of a first dielectric layer and at least one pair of first capacitive element electrodes that sandwich the first dielectric layer and generate a desired electric field in the first dielectric layer. An element body is provided. Furthermore, a first stress control unit is provided that controls the stress generated in the first dielectric layer of the first capacitive element body and increases the capacitance of the first capacitive element body. The power receiving device includes a second resonance capacitor and a second resonance coil connected to the second resonance capacitor. The second resonance coil includes a second capacitor composed of at least one pair of second capacitor elements that sandwich the second dielectric layer and the second dielectric layer and generate a desired electric field in the second dielectric layer. An element body is provided. Further, a second stress control unit is provided for controlling the stress generated in the second dielectric layer of the second capacitive element body and increasing the capacitance of the second capacitive element body.

The power supply device of the present disclosure includes a variable impedance configured to include a power supply unit and a resonant capacitor including a capacitive element. The capacitive element includes a capacitive element body that includes a dielectric layer and at least one pair of capacitive element electrodes that sandwich the dielectric layer and generate a desired electric field in the dielectric layer. Furthermore, the stress control part which controls the stress which generate | occur | produces in the dielectric material layer of a capacitive element main body, and increases the electrostatic capacitance of a capacitive element main body is provided.

The electronic device of the present disclosure includes a resonance capacitor and a resonance coil to which the resonance coil is connected. The resonant capacitor includes a capacitive element body including a dielectric layer and at least one pair of capacitive element electrodes that sandwich the dielectric layer and generate a desired electric field in the dielectric layer. Further, a stress control unit is provided for controlling the stress generated in the dielectric layer of the capacitive element body and increasing the capacitance of the capacitive element body.

According to the present disclosure, it is possible to obtain a capacitive element whose capacitance value is accurately controlled. Moreover, the electrostatic capacity of the capacitive element body can be increased by applying stress to the capacitive element body by the stress control unit. The performance of the resonance circuit can be improved by using these capacitive elements in the resonance circuit.

1 is a schematic cross-sectional configuration diagram of a variable capacitance element according to a first embodiment of the present disclosure. A and B are a circuit configuration and an equivalent circuit diagram of a variable capacitance element according to the first embodiment of the present disclosure. It is the figure which showed the change rate of the electrostatic capacitance Cac obtained by the variable capacitance element main body when applying changing the 1st control voltage V1 and the 2nd control voltage V2. It is the figure which showed the change rate of the electrostatic capacitance Cac of a variable capacitive element main body when the 2nd control voltage V2 is hold | maintained at 0V and only the 1st control voltage V1 is changed. The variable capacitance element when the first control voltage V1 and the second control voltage V2 are opposite in polarity, and the absolute values of the first control voltage V1 and the second control voltage V2 are increased while changing the polarity. It is the figure which showed the change rate of the electrostatic capacitance Cac of a main body. The rate of change of the capacitance Cac of the variable capacitance element body when the first control voltage V1 is alternately changed to 0V and 60V and the second control voltage V2 is alternately changed to 0V and −60V is shown. It is a figure. FIG. 6 is a diagram showing the rate of change of the capacitance Cac of the variable capacitance element body when the polarities of the first control voltage V1 and the second control voltage V2 are the same and are alternately changed to 60V and −60V. FIG. 6 is a diagram showing the rate of change of the capacitance Cac of the variable capacitance element body 2 when the first control voltage V1 and the second control voltage V2 are reversed in polarity and are alternately changed between 60V and −60V. It is the figure which showed the change rate of the electrostatic capacitance Cac of the variable capacitance element main body 2 when the 2nd control voltage V2 is 60V and the 1st control voltage V1 is changed to 0V and 60V alternately. FIG. 6 is a diagram showing the rate of change of the capacitance Cac of the variable capacitance element body 2 when the first control voltage V1 is 60V and the second control voltage V2 is alternately changed to −60V and 60V. It is the figure which showed the change rate of the electrostatic capacitance Cac of the variable capacitance element main body 2 when the 1st control voltage V1 is 60V and the 2nd control voltage V2 is changed to 0V and 60V alternately. The circuit structure concerning the modification 1 of the variable capacitance element concerning a 1st embodiment of this indication is shown. The circuit structure concerning the modification 2 of the variable capacitance element concerning a 1st embodiment of this indication is shown. The circuit structure concerning the modification 3 of the variable capacitance element concerning a 1st embodiment of this indication is shown. The circuit structure concerning the modification 4 of the variable capacitance element concerning a 1st embodiment of this indication is shown. The circuit structure concerning the modification 5 of the variable capacitance element concerning a 1st embodiment of this indication is shown. The circuit structure concerning the modification 6 of the variable capacitance element concerning a 1st embodiment of this indication is shown. The circuit structure concerning the modification 7 of the variable capacitance element concerning a 1st embodiment of this indication is shown. The circuit structure concerning the modification 8 of the variable capacitance element concerning a 1st embodiment of this indication is shown. A to C are process diagrams illustrating a conventional method for manufacturing a variable capacitance element. A to D are process diagrams illustrating a method for manufacturing the variable capacitor according to the first embodiment of the present disclosure. FIG. 6 is a schematic cross-sectional configuration diagram of a variable capacitance element according to a second embodiment of the present disclosure. FIG. 6 is a schematic cross-sectional configuration diagram of a variable capacitance element according to a third embodiment of the present disclosure. It is a block block diagram of the receiving system circuit part of the non-contact IC card using the resonance circuit which concerns on 4th Embodiment of this indication. It is a schematic block diagram of the communication system which concerns on 5th Embodiment of this indication. It is a schematic block diagram of the wireless charging system which concerns on 6th Embodiment of this indication. It is a schematic block diagram of the power supply device which concerns on 7th Embodiment of this indication. It is a schematic cross-sectional block diagram of the variable capacitance element for a principle explanation.

Hereinafter, an example of a capacitive element according to an embodiment of the present disclosure and an electronic apparatus including the same will be described with reference to the drawings. Embodiments of the present disclosure will be described in the following order. Note that the present disclosure is not limited to the following examples.
1. First Embodiment: An Example of Applying the Present Disclosure to a Variable Capacitance Element 1-1 Principle 1-2 Configuration of Variable Capacitance Element 1-3 Measurement Experiment of Capacitance of Variable Capacitance Element 1-4 Manufacturing method 2. Second Embodiment: An example when the present disclosure is applied to a variable capacitance element 3. Third Embodiment: An example when the present disclosure is applied to a variable capacitance element. 4. Fourth embodiment: an example of an electronic device including the variable capacitance element of the present disclosure Fifth embodiment: an example of a communication system including the variable capacitance element of the present disclosure. Sixth Embodiment: An example of a wireless charging system including the variable capacitance element of the present disclosure. Seventh Embodiment: An example of a power supply device including the variable capacitance element of the present disclosure

<1. First Embodiment: Variable Capacitance Element>
[1-1 Principle]
First, before describing the variable capacitance element according to the first embodiment of the present disclosure, the principle of the present embodiment will be described with reference to FIG. 28 in order to facilitate understanding of the variable capacitance element of the present embodiment. .

FIG. 28 shows a schematic cross-sectional configuration of a conventional variable capacitance element for explaining the principle. A variable capacitance element 100 shown in FIG. 28 includes a dielectric layer 103 and at least a pair of

electrodes

101 and 102 that are sandwiched by the dielectric layer 103. One electrode 101 is connected to one external terminal 104, and the other electrode 102 is connected to the other external terminal 105. In the variable capacitance element 100, the dielectric layer 103 is made of a ferroelectric material, and the capacitance changes as the polarization state changes according to the control voltage applied from the outside.

In the variable capacitance element 100 shown in FIG. 28, generally, a sintered material of a ferroelectric material is often used as the ferroelectric material constituting the dielectric layer 103. And, for example, when barium titanate is used as a specific substance, it is known that its crystal state is changed by an electric field generated in the dielectric layer 103. Before explaining the change, the crystal structure of barium titanate will be explained. Although the stable crystal structure varies depending on the temperature, for the sake of easy explanation, the following description will be made only at room temperature. It is known that barium titanate is stable in tetragonal crystal, and the tetragonal crystal has spontaneous polarization in the C-axis direction. The sintered product of barium titanate is polycrystalline, and spontaneous polarization does not appear outside. The reason is as follows.

In the sintered product of barium titanate, there is no spontaneous polarization in the range of very thin thickness in the direction perpendicular to the spontaneous polarization, in contact with the small area of the tetragonal crystal with spontaneous polarization (side surface parallel to the spontaneous polarization direction) There are cubic crystals. In addition, there is another small region of tetragonal crystal in which the cubic crystal is interposed and is in contact with the cubic crystal and has spontaneous polarization opposite to the direction of the spontaneous polarization region. In addition, cubic crystals exist in a very thin thickness range in the direction of 45 degrees with respect to the C-axis in the end region in the C-axis direction of the small region cubic crystal, and the cubic crystal in the small region is 90 to each other. There may also be other microregions of cubic crystals with a degree (orthogonal) orientation and spontaneous polarization.

Furthermore, the spontaneous polarization region becomes a collective region composed of a plurality of small regions of several tetragonal crystals existing so that the polarizations cancel each other through the cubic crystal. In addition, as described above, the micro regions exist also in the adjacent collective region, in an arrangement parallel to and orthogonal to the C-axis direction of the main tetragonal crystal in the collective area.
For the above reasons, polarization does not appear to the outside as a whole of the sintered barium titanate. In this case, it is also known that the so-called C-axis lattice constant, which is the polarization direction of tetragonal crystal, is longer than the lattice constant of the original cubic C-axis.

In the variable capacitance element 100 shown in FIG. 28, for example, when a sintered material of barium titanate is used as the ferroelectric material constituting the dielectric layer 103, the crystal state is changed depending on the electric field generated in the dielectric layer 103. How it changes will be described. There are a plurality of patterns in how the crystal state changes, and it is known that it depends on the strength and application time of the electric field, the reversal of the direction of the electric field, and the period (frequency) of the reversal.

The typical pattern of how the crystal state changes is as follows. First, an electric field in the dielectric layer is applied. Then, a very narrow region plane (domain) between a small region of a tetragonal crystal having a spontaneous polarization parallel to (and nearly parallel to) the electric field direction and a small region of a tetragonal crystal having a spontaneous polarization in the 90-degree direction adjacent thereto. The crystal type changes continuously as if the wall were moving. Then, the tetragonal microregions with the spontaneous polarization (and near parallel) spontaneously erode the tetragonal microregions with the spontaneous polarization in the 90-degree direction. That is, a large amount of polarization is arranged in the electric field direction. At this time, when the two minute regions are viewed together, they expand in the direction of the electric field and contract in the direction perpendicular to the direction of the electric field.

In addition, when the electric field strength is large and the time is applied for a long time, in the collective region parallel to and parallel to the electric field direction, a very narrow region plane (domain wall) of the tetragonal crystal moves in the collective region, and the reverse direction A large amount of polarization is arranged in the direction of the electric field so as to erode a minute region. And if it tries to make a reverse micro area | region, it will come to be eroded from the circumference | surroundings and finally a reverse micro area | region will lose | disappear. Of course, the cubic region also disappears. At this time, when one collective region is viewed together, the direction orthogonal to the electric field direction is neither expanded nor contracted. In addition, the amount of elongation in the electric field direction is slightly increased by the amount of the cubic crystal region disappeared and changed to tetragonal crystal.

In addition, it is known that the entire polarization is reversed without the movement of a very narrow region plane (domain wall) of tetragonal crystal as described above with respect to the applied electric field.
A high dielectric constant can be obtained in accordance with such a change in the crystalline state of barium titanate or a change in the polarization direction. In addition, by applying a DC bias voltage called so-called domain clamping, it becomes difficult to reverse the polarity of the AC electric field caused by the superimposed AC voltage, and control is performed to change the capacitance by the DC bias voltage. You can also
Based on such considerations, the present inventors can control the polarization state, dielectric constant, and electrostatic capacity of barium titanate by promoting or inhibiting the extension of barium titanate by the applied electric field. The knowledge that it might be.

In the variable capacitance element 100 as shown in FIG. 28, since a dedicated control terminal for controlling the capacitance is not configured, the control voltage for changing the capacitance and the signal voltage (alternating current) are between the same electrodes (see FIG. 28). 28, it is applied to the electrode 101 and the electrode 102). For this reason, the sum of the control voltage and the signal voltage is applied to the dielectric layer 103. Then, the crystal state of barium titanate constituting the dielectric layer 103 changes in accordance with the direction of the electric field generated in the dielectric layer 103, and the barium titanate expands or contracts back to the original state. A phenomenon of contraction occurs. As a result, the entire dielectric layer 103 expands or contracts back in the direction of the electric field, and further contracts from the original state.

At this time, an electrostatic force (Coulomb force) is generated between the pair of

electrodes

101 and 102 that generate an electric field in the dielectric layer 103 as indicated by arrows A and B. The electric field (electrode) acts to compress the dielectric layer 103 by this Coulomb force.

Based on these considerations, the present inventors have also obtained the knowledge that the coulomb force works to inhibit the elongation of barium titanate.

When a control voltage is applied to the dielectric layer 103 composed of barium titanate, the polarization domains are aligned in the direction of the electric field, and the capacitance changes. However, for the reasons described above, it is considered that the Coulomb force inhibits the dislocation of the barium titanate crystal state and prevents the polarization domains from being aligned, thereby reducing the capacitance variable rate.

In the variable capacitance element 100 shown in FIG. 28, when the signal voltage (alternating current) applied to the dielectric layer 103 is particularly larger than the control voltage, the capacitance variable ratio due to the control voltage is reduced, and the dielectric loss is large. There was a problem of becoming. These phenomena are also considered because the electric field (electrode) brings compressive stress to the dielectric layer 103 due to Coulomb force acting between the electrodes.

Therefore, the present inventors, when configuring a variable capacitance element, use a configuration that can reduce or increase the stress on the dielectric layer, thereby improving the capacitance variable rate, reducing the dielectric loss, We thought that capacity could be stabilized.

[1-2 Configuration of variable capacitance element]
Based on the above principle, the variable capacitance element according to the first embodiment will be described. FIG. 1 is a schematic cross-sectional configuration diagram of a variable capacitance element 1 of the present embodiment. 2A is a circuit configuration of the variable capacitance element 1 of the present embodiment, and FIG. 2B is an equivalent circuit diagram of the variable capacitance element 1 of the present embodiment.

As shown in FIG. 1, the variable capacitance element 1 of the present embodiment is composed of a variable capacitance element main body 2 and

stress control units

6 and 7 that are provided on the upper and lower sides thereof. The variable capacitance element body 2 includes a dielectric layer 4, first and second variable

capacitance element electrodes

5 a and 5 b formed by alternately laminating a plurality of layers with the dielectric layer 4 interposed therebetween, and first and

second Signal terminals

3a and 3b.

The first and second variable

capacitance element electrodes

5 a and 5 b are formed of rectangular plate-like members, and are alternately stacked via the dielectric layers 4. The end portion of the first variable capacitance element electrode 5 a is formed so as to be exposed from one side surface of the dielectric layer 4. On the other hand, the end portion of the second variable capacitance element electrode 5 b is formed so as to be exposed from the other side surface facing one side surface of the dielectric layer 4. The first signal terminal 3 a is formed on one side surface of the dielectric layer 4 and is electrically connected to the end portion of the first variable capacitance element electrode 5 a exposed on the side surface of the dielectric layer 4. The second signal terminal 3 b is formed on the other side surface of the dielectric layer 4 and is electrically connected to the end of the second variable capacitance element electrode 5 b exposed on the side surface of the dielectric layer 4. ing.

As a material for forming the first and second variable

capacitance element electrodes

5a and 5b, a metal material such as Pt, Pb, Pb / Ag, Ni, Ni alloy or the like can be used. The dielectric layer 4 is formed of a dielectric material whose dielectric constant is changed by applying a voltage between the first and second variable

capacitance element electrodes

5a and 5b sandwiching the dielectric layer 4. For example, it is made of a ferroelectric material having a relative dielectric constant exceeding 1000.

As a material for the dielectric layer 4, specifically, a dielectric material that causes ion polarization can be used. A ferroelectric material that causes ion polarization is a ferroelectric material that is made of an ionic crystal material and is electrically polarized by the displacement of positive and negative ion atoms. In general, a ferroelectric material that generates ionic polarization is represented by the chemical formula ABO ₃ (O is an oxygen element) and has a perovskite structure, where A and B are two predetermined elements. Examples of such a ferroelectric material include barium titanate (BaTiO ₃ ), potassium niobate (KNbO ₃ ), lead titanate (PbTiO ₃ ), and the like. Moreover, PZT (lead zirconate titanate) obtained by mixing lead zirconate (PbZrO ₃ ) with lead titanate (PbTiO ₃ ) may be used as a material for forming the dielectric layer 4.

Further, a ferroelectric material that generates electronic polarization may be used as the material for forming the dielectric layer 4. In this ferroelectric material, an electric dipole moment is generated in a portion biased to a positive charge and a portion biased to a negative charge, and polarization occurs. As such a material, a rare earth iron oxide having a ferroelectric property by forming polarization by forming a charge surface of Fe ^{2+ and} a charge surface of Fe ³⁺ has been reported. In this system, when the rare earth element is RE and the iron group element is TM, the material represented by the molecular formula (RE) · (TM) ₂ · O ₄ (O: oxygen element) has a high dielectric constant. It has been reported. Examples of rare earth elements include Y, Er, Yb, and Lu (particularly Y and heavy rare earth elements), and examples of iron group elements include Fe, Co, and Ni (particularly Fe). Examples of (RE) · (TM) ₂ · O ₄ include ErFe ₂ O ₄ , LuFe ₂ O ₄ , and YFe ₂ O ₄ .

In the variable capacitor element body 2, as shown in FIGS. 2A and 2B, by applying a desired signal voltage from the signal voltage power supply AC to the first signal terminal 3a and the second signal terminal 3b, the adjacent first In addition, a capacitance Cac is obtained between the second variable

capacitance element electrodes

5a and 5b.

The

stress control units

6 and 7 include first and second

stress control electrodes

9a and 9b, and first and second control terminals, which are alternately stacked in layers with the dielectric layer 10 for stress control unit interposed therebetween. 8a and 8b. The first and second

stress control electrodes

9a and 9b are formed of rectangular plate-like members, and are alternately stacked with the stress control portion dielectric layers 10 interposed therebetween. The end portion of the first stress control electrode is formed so as to be exposed from one side surface of the stress control portion dielectric layer 10. On the other hand, the end portion of the second stress control electrode 9b is formed so as to be exposed from the other side surface opposed to one side surface of the stress control unit dielectric layer 10. The first control terminal 8a is formed on one side surface of the stress control unit dielectric layer 10, and is electrically connected to the end portion of the first stress control electrode 9a exposed on the side surface of the stress control unit dielectric layer 10. It is connected. The second control terminal 8 b is formed on the other side surface of the stress control unit dielectric layer 10, and the end of the second stress control electrode 9 b exposed on the side surface of the stress control unit dielectric layer 10. It is electrically connected to the part.

The

stress controllers

6 and 7 are configured to sandwich the variable capacitor element body 2 in the thickness direction of the dielectric layer 4 of the variable capacitor element body 2 (the direction in which the electric field is generated). Further, the first and second

stress control electrodes

9a and 9b are for the stress control unit while substantially maintaining a parallel relationship with the first and second variable

capacitance element electrodes

5a and 5b constituting the variable capacitance element body 2. The dielectric layers 10 are alternately stacked.

In FIG. 1, the thickness of the stress control portion dielectric layer 10 (the distance between the first stress control electrode 9 a and the second stress control electrode 9 b) and the thickness of the dielectric layer 4 (first variable). The distance between the capacitive element electrode 5a and the second variable capacitive element electrode 5b) is the same. However, the present invention is not limited to this and may be different. In addition, the thickness (distance between the first stress control electrode 9a and the second stress control electrode 9b) of each dielectric layer for stress control unit 10 shown in FIG. 1 may be different.

As a forming material of the stress control unit dielectric layer 10 constituting the

stress control units

6 and 7, the same material as the forming material of the dielectric layer 4 constituting the variable capacitance element body 2 can be used. In addition, it is possible to use a material that is harder than the dielectric layer 4 of the variable capacitance element body 2 or a material having a higher compressibility with respect to an applied stress control voltage (electric field). Such a substance may be selected from specific examples of a material for forming the dielectric layer 4 constituting the variable capacitance element body 2 or may be selected from generally used dielectric materials. The dielectric material that is generally used, paper, polyethylene terephthalate, polypropylene, polyphenylene sulfide, _{_{_{polystyrene, TiO 2, MgTiO 2, SrMgTiO}}} 2, Al 2 O 3, Ta 2 O 5, and the like.

As a material for forming the first and second

stress control electrodes

9a and 9b, a metal material such as Pt, Pb, Pb / Ag, Ni, Ni alloy or the like is used as in the electrode constituting the variable capacitance element body 2. it can.

In the variable capacitance element 1 having such a configuration, as shown in FIGS. 2A and 2B, in the upper layer stress control section 6, the first control terminal 8a and the second control terminal 8b are connected to the first stress control first. The first control voltage V1 is applied by the control voltage power source DC1. On the other hand, in the lower stress control unit 7, the second control voltage V2 is applied to the first control terminal 8a and the second control terminal 8b by the second control voltage power source DC2 for stress control. Then, a Coulomb force is generated between the first stress control electrode 9a and the second stress control electrode 9b, and in the first and second

stress control electrodes

9a and 9b other than the outermost electrode, the surface of the electrode On the side and the back side, Coulomb forces are generated in the opposite directions. For this reason, although the Coulomb forces generated in the first and second

stress control electrodes

9a and 9b other than the outermost electrode are canceled out, the outermost electrodes of the

stress control portions

6 and 7 pull the dielectric layer 4. Coulomb force is generated in the direction. Therefore, tensile stress is generated in the dielectric layer 4 of the variable capacitance element body 2 by the

stress control units

6 and 7 formed above and below.

In such a state, the polarization state in the dielectric layer 4 can be easily changed between the first and second variable

capacitor element electrodes

5a and 5b of the variable capacitor element body 2 in accordance with the signal voltage. For this reason, the capacitance Cac of the dielectric layer 4 can be increased as compared with the case where the control voltage is not applied to the

stress controllers

6 and 7. That is, the dislocation of the crystal structure in the dielectric layer 4 becomes easier as compared with the conventional one in which no control voltage is applied. For this reason, the loss (dielectric loss) at the time of dislocation of the crystal structure of the dielectric material in the dielectric layer 4 is also smaller than that of the conventional one.

As described above, in the variable capacitance element 1 of the present embodiment, by applying a control voltage to the

stress control units

6 and 7, it is possible to bring a tensile stress to the variable capacitance element body 2, and thereby, the variable capacitance element The capacitance Cac of the main body 2 can be increased.

[1-3 Measurement experiment of capacitance of variable capacitance element]
Next, an experiment for measuring the change rate of the capacitance Cac using the variable capacitance element of the present embodiment will be described. In the measurement experiment, barium titanate was used for the dielectric layer 4 of the variable capacitance element body 2 and the stress control unit dielectric layer 10 of the

stress control units

6 and 7, and each dielectric layer 4 and the stress control unit dielectric. The layer thickness of the body layer 10 was 3 μm. The first and second variable

capacitance element electrodes

5a and 5b and the first and second

stress control electrodes

9a and 9b are made of nickel, and the layer thickness of each electrode is 1 μm. In the variable capacitance element 1, the length between the terminals is 3.2 mm, the width of the side surface where each terminal is formed is 1.6 mm, and the dielectric layer 4 and the stress control unit dielectric layer 10 in the thickness direction. The height was 1.6 mm. In addition, the thickness of the variable capacitor element body 2 was set to about 0.15 mm, and the distance between the variable capacitor element body 2 and the upper and lower

stress control units

6 and 7 was set to 0.10 mm. In such a configuration, the capacitance C1 of the upper layer stress control unit 6 portion was 3.25 μF, and the capacitance C2 of the lower layer stress control unit 7 portion was 3.14 μF. Further, the capacitance Cac of the variable capacitance element body 2 when no control voltage was applied to the

stress controllers

6 and 7 was 1.35 μF. In addition, these electrostatic capacitances were measured according to a measuring instrument and measurement conditions described later.

This measurement experiment was performed using the equivalent circuit shown in FIG. 2B. As shown in FIG. 2B, in the upper-layer stress control unit 6, the first control terminal 8a is connected to one terminal of the first control voltage power source DC1 via the current limiting resistor _R1a to perform the second control. terminal 8b is connected to the other terminal of the first control voltage supply DC1 through the current limiting resistor R _1b. Further, in the lower layer of stress control unit 7, the first control terminal 8a is connected to one terminal of the second control voltage supply DC2 through the current limiting resistor R _2a, the second control terminal 8b current limit through a resistor R _2b is connected to the other terminal of the second control voltage supply DC2.

As described above, in the present embodiment, only the signal voltage power supply AC is connected to the variable capacitance element body 2, and only the first control voltage power supply DC1 or the second control voltage power supply DC2 is connected to the

stress controllers

6 and 7. Is connected. That is, in the variable capacitance element 1, the AC terminal and the DC terminal are provided independently. The

stress controllers

6 and 7 and the variable capacitor element body 2 are electrically independent.

In such a configuration, the upper layer stress control unit 6 supplies the first control voltage V1 supplied from the first control voltage power source DC1 to the first and second

stress control electrodes

9a and 9b, A capacitance C1 is obtained. In the lower stress control unit 7, the second control voltage V2 supplied from the second control voltage power source DC2 is supplied to the first and second

stress control electrodes

9a and 9b, and the capacitance C2 is obtained. It is done.

On the other hand, a signal voltage power supply AC is connected between the first and

second signal terminals

3 a and 3 b of the variable capacitance element body 2. The electrostatic capacity Cac is measured by causing a desired signal current (alternating current) to flow from the signal voltage power source AC to the variable capacitance element body 2.
In this measurement experiment, an impedance analyzer model number 4294A manufactured by Agilent Technologies is used as a capacitance measuring device which also serves as a signal voltage power supply AC, and Yokogawa is used as the first control voltage power supply DC1 and the second control voltage power supply DC2. An electric source measure unit model number GS610 was used. In this measurement experiment, the frequency transmitted from the signal voltage power supply AC was 1 kHz, the amplitude was 500 mVrms, and each current limiting resistance R _1a , R _1b , R _2a , R _2b was 510 kΩ.

FIG. 3 is a graph showing the rate of change of the capacitance Cac obtained in the variable capacitance element body 2 when the first control voltage V1 and the second control voltage V2 are applied while being changed. In FIG. 3, the horizontal axis indicates time, and the vertical axis indicates first and second control voltages V1 and V2 applied between the first and

second control terminals

8a and 8b, and the variable capacitance element body 2 at that time. The rate of change of the capacitance Cac obtained in (1) is shown. The change rate of the capacitance Cac is based on the capacitance measured at the start of measurement, that is, at time zero.

As shown in FIG. 3, in the variable capacitance element 1 of the present embodiment, the first and

second signal terminals

3a and 3b are increased by increasing the absolute values of the first control voltage V1 and the second control voltage V2. It can be seen that the capacitance Cac obtained between the two increases. That is, increasing the control voltage applied to the

stress controllers

6 and 7 increases the capacitance Cac of the variable capacitance element body 2.

FIG. 4 shows the rate of change of the capacitance Cac of the variable capacitance element body 2 when the second control voltage V2 is held at 0 V and only the first control voltage V1 is changed in the circuit configuration of FIG. 2B. FIG. That is, the change rate of the capacitance Cac of the variable capacitance element body 2 is measured when no control voltage is applied to the lower stress control section 7 and only the upper stress control section 6 is applied. is there.

It can be seen that when the second control voltage V2 is set to 0 V, the increase rate of the capacitance Cac of the variable capacitance element body 2 is approximately halved compared to the result shown in FIG. From the results of FIGS. 3 and 4, it can be seen that the stress generated in each of the

stress controllers

6 and 7 contributes to the increase in the capacitance Cac in the variable capacitance element body 2.

FIG. 5 shows that in the circuit configuration of FIG. 2B, the first control voltage V1 and the second control voltage V2 are opposite in polarity, and the absolute values of the first control voltage V1 and the second control voltage V2 are changed in polarity. It is the figure which showed the change rate of the electrostatic capacitance Cac of the variable capacitance element main body 2 when it enlarged, however. It can be seen that when the absolute values of the first control voltage V1 and the second control voltage V2 are gradually changed from 0, the capacitance Cac of the variable capacitance element body 2 also increases. However, when the polarities of the first control voltage V1 and the second control voltage V2 are changed, the capacitance Cac of the variable capacitance element body 2 gradually increases from the moment when the polarities are changed, and after a certain time has elapsed. Stabilize.

FIG. 6 shows the variable capacitance when the first control voltage V1 is alternately changed to 0V and 60V and the second control voltage V2 is alternately changed to 0V and −60V in the circuit configuration of FIG. 2B. FIG. 5 is a diagram showing a rate of change of capacitance Cac of the element body 2. That is, the first control voltage V1 and the second control voltage V2 have opposite polarities. Also in this case, when the absolute values of the first control voltage V1 and the second control voltage V2 are 60V, the capacitance Cac of the variable capacitance element body 2 increases, and the first control voltage V1 and the second control voltage V2 When the control voltage V2 was set to 0V, the change rate of the capacitance Cac was about 0%.

FIG. 7 shows a change in the capacitance Cac of the variable capacitance element body 2 when the first control voltage V1 and the second control voltage V2 are alternately changed to 60 V and −60 V in the circuit configuration of FIG. 2B. It is the figure which showed the rate. Although the rate of increase of the capacitance Cac of the variable capacitance element body 2 at the moment when the polarities of the first control voltage V1 and the second control voltage V2 change, it decreases after a certain time has elapsed.

FIG. 8 shows the static capacitance of the variable capacitor element body 2 when the first control voltage V1 and the second control voltage V2 have opposite polarities in the circuit configuration of FIG. 2B and are alternately changed to 60V and −60V, respectively. It is a figure showing change rate of electric capacity Cac. Although the increasing rate of the capacitance Cac of the variable capacitance element body 2 at the moment when the polarities of the first control voltage V1 and the second control voltage V2 change, the capacitance Cac is stabilized after a certain time has elapsed. Further, under the conditions of FIG. 8, the increasing rate of the capacitance Cac of the variable capacitance element body 2 is higher than that of FIG. This is because the number of stacked stress control electrodes in the upper layer stress control unit 6 and the lower layer stress control unit 7 is different, or the stress control electrodes (9a, 9b) and the variable capacitance element electrodes (5a, 5b) This is considered to be due to the formation of a capacitance between the two.

FIG. 9 shows the capacitance Cac of the variable capacitance element body 2 when the second control voltage V2 is set to 60V and the first control voltage V1 is alternately changed between 0V and 60V in the circuit configuration of FIG. 2B. It is the figure which showed the rate of change. When both the first and second control voltages V1 and V2 are 60V, the rate of increase of the capacitance Cac of the variable capacitance element body 2 compared to when only the second control voltage V2 is 60V It can be seen that is approximately doubled.

FIG. 10 shows the capacitance Cac of the variable capacitance element body 2 when the first control voltage V1 is set to 60V and the second control voltage V2 is alternately changed between 0V and 60V in the circuit configuration of FIG. 2B. It is the figure which showed the rate of change. When both the first and second control voltages V1 and V2 are 60V, the capacitance Cac increases even when the first control voltage V1 is 60V and the second control voltage V2 is 60V. ing.

FIG. 11 shows the capacitance Cac of the variable capacitance element body 2 when the first control voltage V1 is set to 60V and the second control voltage V2 is alternately changed to −60V and 60V in the circuit configuration of FIG. 2B. It is the figure which showed the change rate. It can be seen that the electrostatic capacitance Cac of the variable capacitance element body 2 increases in the same manner when the second control voltage V2 is 60V or −60V.
9 and 11, it can be seen that each of the Coulomb forces generated in the upper and

lower stress controllers

6 and 7 affects the rate of change of the capacitance Cac of the variable capacitance element body 2. It can also be seen that the upper layer stress control unit 6 has a greater influence on the variable capacitance element body 2 than the lower layer stress control unit 7.

As described above, in the variable capacitance element 1 of the present embodiment, the capacitance Cac of the variable capacitance element body 2 increases as the absolute values of the first control voltage V1 and the second control voltage V2 are increased. I understood it. That is, the tensile stress due to the Coulomb force generated between the first stress control electrode 9 a and the second stress control electrode 9 b in the

stress control units

6 and 7 has an effect of increasing the capacitance Cac of the variable capacitance element body 2. Proven to connect.

Further, according to the present embodiment, the control voltage may be applied only to the

stress control units

6 and 7 formed above and below, and the first and

second signal terminals

3a and 3b in the variable capacitance element body 2 are applied to the first and

second signal terminals

3a and 3b. Only the signal voltage is applied. As described above, in the present embodiment, the capacitance Cac of the variable capacitance element body 2 can be increased without directly applying a control voltage to the variable capacitance element body 2, and the signal ( AC) voltage and control (DC) voltage can be completely separated.

In the circuit configuration of the variable capacitance element 1 of the present embodiment, the upper layer stress control unit 6 and the lower layer stress control unit 7 are electrically separated from each other, but may be connected to each other. FIG. 12 shows a circuit configuration according to Modification 1 of the variable capacitance element 1 of the present embodiment.

In the circuit configuration according to the first modification, the first control terminal 8a of the upper stress control unit 6, connected to one terminal of the first control voltage supply DC1 through the current limiting resistor R _a, of the second The control terminal 8b is connected to the other terminal of the first control voltage power supply DC1 through the current limiting resistor _Rb . The first control terminal 8a of the underlying stress control unit 7 is connected between the second control terminal 8b and the current limiting resistor R _b of the upper layer of the stress control unit 6, the second control voltage supply DC2 Is connected between the current limiting resistor _Rb and the first control voltage power supply DC1. The second control terminal 8b in the lower layer of stress control unit 7 is connected to the other terminal of the second control voltage supply DC2 through the current limiting resistor R _c.

FIG. 13 shows a circuit configuration according to Modification 2 of the variable capacitance element 1 of the present embodiment. In the second modification connects the first control terminal 8a of the upper stress control unit 6, to the terminal of the first control voltage supply DC1 through the current limiting resistor R _a, a second control terminal 8b Is connected to the other terminal of the first control voltage power supply DC1 via the current limiting resistor _Rb . Further, the lower layer of stress control unit 7, connects the first control terminal 8a, to one terminal of the second control voltage supply DC2 through the current limiting resistor R _c. Then, the second control terminal 8b of the lower layer of the stress control unit 7, is connected between the first control terminal 8a and the current limiting resistor R _a of the upper layer of the stress control unit 6, the second control voltage supply DC2 Is connected between the current limiting resistor _Ra and one terminal of the first control voltage power source DC1.

FIG. 14 shows a circuit configuration according to Modification 3 of the variable capacitance element 1 of the present embodiment. In Modification 3, connects the first control terminal 8a of the upper stress control unit 6, to the terminal of the first control voltage supply DC1 through the current limiting resistor R _a, a second control terminal 8b Is connected to the other terminal of the first control voltage power supply DC1 via the current limiting resistor _Rb . Further, the first control terminal 8a of the underlying stress control unit 7, is connected between the first control terminal 8a and the current limiting resistor R _a of the upper layer of the stress control unit 6, the second control voltage supply DC2 one terminal of is connected between the current limiting resistor R _a first control voltage source DC1. Then, to connect the second control terminal 8b of the lower layer of the stress control unit 7, to the other terminal of the second control voltage supply DC2 through the current limiting resistor R _c.

FIG. 15 shows a circuit configuration according to Modification 4 of the variable capacitance element 1 of the present embodiment. In Modification 4, connects the first control terminal 8a of the upper stress control unit 6, to the terminal of the first control voltage supply DC1 through the current limiting resistor R _a. In addition, the first control terminal 8a of the lower layer stress control unit 7 is connected to one terminal of the second control voltage power source DC2 via the current limiting resistor _Rb , and the second control terminal 8b is connected to the current limiting resistor _Rb. through a resistor R _c is connected to the other terminal of the second control voltage supply DC2. Then, the second control terminal 8b in the upper layer of stress control unit 6 is connected between the second control terminal 8b and the current limiting resistor R _c of the lower stress control unit 7, the first control voltage supply DC1 Is connected between the current limiting resistor _Rc and the second control voltage power supply DC2.

FIG. 16 shows a circuit configuration according to Modification 5 of the variable capacitance element 1 of the present embodiment. Modification 5 is configured to connect the second control terminal 8b of the first control terminal 8a and a lower stress control unit 7 of the upper layer of stress control unit 6 to each other, the control voltage source through a current limiting resistor R _a Connect to one terminal of DC. Further, the second control terminal 8b of the upper layer stress control unit 6 and the first control terminal 8a of the lower layer stress control unit 7 are connected to each other, and the other of the control voltage power source DC is connected via the current limiting resistor _Rb . Connect to the terminal.

FIG. 17 shows a circuit configuration according to Modification 6 of the variable capacitance element 1 of the present embodiment. Modification 6 is configured to connect the second control terminal 8b of the first control terminal 8a and a lower stress control unit 7 of the upper layer of stress control unit 6 to each other, the control voltage source through a current limiting resistor R _a Connect to one terminal of DC. Further, the second control terminal 8b of the upper layer stress control unit 6 and the first control terminal 8a of the lower layer stress control unit 7 are connected to each other, and the other of the control voltage power source DC is connected via the current limiting resistor _Rb . Connect to the terminal.

FIG. 18 shows a circuit configuration according to Modification 7 of the variable capacitance element 1 of the present embodiment. In the seventh modification, the first control terminal 8a of the upper stress control unit 6 is connected to one terminal of the control voltage source DC through the current limiting resistor R _a, of the underlying stress control unit 7 second The control terminal 8b is connected to the other terminal of the control voltage power supply DC through the current limiting resistor _Rb . Then, the second control terminal 8 b of the upper layer stress control unit 6 and the first control terminal 8 a of the lower layer stress control unit 7 are connected.

FIG. 19 shows a circuit configuration according to Modification 8 of the variable capacitance element 1 of the present embodiment. Modification 8, the first control terminal 8a of the upper stress control unit 6 is connected to one terminal of the control voltage source DC through the current limiting resistor R _a, of the underlying stress control unit 7 first The control terminal 8a is connected to the other terminal of the control voltage power source DC through the current limiting resistor _Rb . Then, the second control terminal 8b of the upper layer stress control unit 6 and the second control terminal 8b of the lower layer stress control unit 7 are connected.

As described above, various modifications can be made to the circuit configuration for driving the variable capacitance element 1 of the present embodiment. In any of the modifications, the variable voltage element 1 can be changed by applying a control voltage to the

stress control units

6 and 7. The capacitance Cac of the capacitive element body 2 can be increased.

By the way, the conventional capacitive element that changes the capacitance according to the control voltage has a characteristic that the capacitance decreases by applying the control voltage. In this embodiment, since the electrostatic capacity can be increased by applying the control voltage, the range of applications as a variable capacitance element can be expanded.

[1-4 Method for Manufacturing Variable Capacitance Element]
Next, an example of a method for manufacturing the variable capacitance element 1 having the above configuration will be described. First, a general conventional method of manufacturing a capacitive element will be described with reference to FIGS. 20A to 20C. As shown in FIG. 20A, a dielectric sheet 20 made of a desired dielectric material is prepared. The dielectric sheet 20 constitutes the dielectric layer 4 in the variable capacitance element body 2, and the dielectric layer 10 for the stress control part in the

stress control parts

6 and 7. These dielectric sheets 20 can be formed by forming a pasty dielectric material, for example, on a PET (polyethylene terephthalate) film to a desired thickness. Also, a mask is prepared in which regions corresponding to the formation regions of the first and second variable

capacitance element electrodes

5a and 5b and the first and second

stress control electrodes

9a and 9b constituting the variable capacitance element body 2 are opened. To do.

Next, a conductive paste in which a metal powder such as Pt, Pb, Pb / Ag, Ni, Ni alloy or the like is pasted is controlled, and the conductive paste 21 is passed through the respective masks prepared in the previous stage, and then the dielectric sheet 20. Apply on top (silk printing, etc.). As a result, the first and second variable

capacitance element electrodes

5a and 5b and the first and second

stress control electrodes

9a and 9b are formed on one surface of the dielectric sheet 20, respectively.

Then, as shown in FIG. 20B, each dielectric sheet 20 on which the first and second variable

capacitance element electrodes

5a and 5b and the first and second

stress control electrodes

9a and 9b are formed, Laminate in the desired order by aligning the orientation of the printed surface. Further, dielectric sheets 20 on which no electrodes are printed are laminated on the upper and lower sides of this laminated body, and are subjected to pressure bonding.

Then, as shown in FIG. 20C, the pressure-bonded member is fired at a high temperature in a reducing atmosphere to integrate the dielectric sheet 20 and the electrodes formed of the conductive paste 21. In the present embodiment, the variable capacitance element 1 is formed in this way.
Then, since no electrode is formed on the dielectric sheet 20 at the end portion of the capacitive element, the total thickness after sintering becomes thinner than the total thickness at the central portion of the capacitive element. As a result, as shown in FIG. 20C, there is a problem that the end of the capacitive element becomes thin and the mechanical strength becomes low. In the variable capacitance element 1 of the present embodiment, when the mechanical strength is low, there is a problem that even if the

stress control units

6 and 7 are configured, the tensile stress applied to the variable capacitance element body 2 cannot be sufficiently exhibited.

Therefore, a manufacturing method of the variable capacitance element of the present embodiment capable of maintaining the mechanical strength will be described with reference to FIGS. 21A to 21D. 21A to 21D show cross sections in which the electrodes are not exposed at the end portions.

First, as shown in FIG. 21A, a dielectric sheet 20 made of a desired dielectric material is prepared. The dielectric sheet 20 constitutes the dielectric layer 4 in the variable capacitance element body 2, and the dielectric layer 10 for the stress control part in the

stress control parts

6 and 7. These dielectric sheets 20 can be formed by forming a pasty dielectric material, for example, on a PET (polyethylene terephthalate) film to a desired thickness. In addition, a mask is prepared in which regions corresponding to regions where the first and second variable

capacitance element electrodes

5a and 5b and the first and second

stress control electrodes

9a and 9b are formed are opened.

Next, a conductive paste in which a metal powder such as Pt, Pb, Pb / Ag, Ni, Ni alloy or the like is made into a paste is prepared, and the conductive paste 21 is passed through the respective masks prepared in the previous stage through the dielectric sheet 20. Apply on top (silk printing, etc.). As a result, the first and second variable

capacitance element electrodes

5a and 5b and the first and second

stress control electrodes

9a and 9b are formed on one surface of the dielectric sheet 20, respectively.

Next, as shown in FIG. 21B, a dielectric material film 22 is formed around the conductive paste 21 so as to embed the periphery of the conductive paste 21 constituting each electrode formed on the dielectric sheet 20. Here, on the surface of the dielectric sheet 20, the width of the end portion where the conductive paste 21 is not formed is 10% to 20% of the entire width, and the portion is filled with the dielectric material film 22. Then, the surface of the dielectric material film 22 and the surface of the conductive paste 21 are made substantially the same.

Then, as shown in FIG. 21C, each dielectric sheet 20 on which each electrode is formed is laminated in a desired order with the orientation of the surface on which each electrode is printed aligned. When the variable capacitance element body 2 is sandwiched between the

stress control units

6 and 7 as in the variable capacitance element 1 of the present embodiment, a plurality of first and second

stress control electrodes

9a and 9b are alternately stacked. Thereafter, a plurality of first and second variable

capacitance element electrodes

5a and 5b are alternately stacked. Further, a plurality of first and second

stress control electrodes

9a and 9b are alternately laminated, and dielectric sheets 20 on which no electrodes are printed are laminated on the upper and lower sides of the laminated body, followed by pressure bonding.

Then, as shown in FIG. 21D, the pressure-bonded member is fired at a high temperature in a reducing atmosphere, and the dielectric sheet 20 and each electrode formed of the conductive paste 21 are integrated. In the present embodiment, the variable capacitance element 1 is formed in this way.

In the manufacturing method of the variable capacitance element of this embodiment, since the periphery of the conductive paste 21 formed on the dielectric sheet 20 is embedded with the dielectric material film 22, when the plurality of dielectric sheets 20 are stacked and fired, It is possible to prevent the periphery of the variable capacitance element 1 from being thinned. Thereby, the mechanical strength around the variable capacitance element 1 can be increased. For this reason, the tensile stress due to the Coulomb force generated in the

stress control units

6 and 7 can be sufficiently transmitted to the variable capacitance element body 2.

21A to 21C show cross sections in which the electrodes are not exposed at the end portions, but in the cross sections in which the stacked electrodes are alternately exposed on the opposite side surfaces, the dielectric material is not formed in the portion where the conductive paste 21 is not formed. A film 22 is formed. Thereby, it is possible to prevent the variable capacitance element 1 from being thin even around the side where the signal terminal and the control terminal are formed, and it is possible to generate tensile stress more effectively.

<2. Second Embodiment: Variable Capacitance Element>
Next, a variable capacitance element according to the second embodiment of the present disclosure will be described. FIG. 22 is a schematic configuration diagram of the variable capacitance element 24 of the present embodiment. In FIG. 22, parts corresponding to those in FIG. This embodiment is an example in which the thickness w1 of the dielectric layer 4 of the variable capacitance element body 2 and the thickness w2 of the stress control unit dielectric layer 10 in the

stress control units

6 and 7 are different.

In the present embodiment, the thickness (distance between the first and second

stress control electrodes

9a and 9b) w2 of the stress control unit dielectric layer 10 in the

stress control units

6 and 7 is set to the dielectric layer of the variable capacitance element body 2. 4 (the distance between the first and second variable

capacitance element electrodes

5a and 5b) w1. As a result, the electric field strength at the

stress control units

6 and 7 is increased, and a larger stress can be generated. As a result, the tensile stress applied to the variable capacitance element main body 2 increases, and when a control voltage is applied to the

stress control units

6 and 7, the capacitance Cac of the variable capacitance element main body 2 is more likely to increase.

<3. Third Embodiment: Variable Capacitance Element>
Next, a variable capacitance element according to the third embodiment of the present disclosure will be described. FIG. 23 is a schematic configuration diagram of the variable capacitance element 25 of the present embodiment. In FIG. 23, parts corresponding to those in FIG. This embodiment is an example in which the material of the dielectric layer 26 of the variable capacitance element body 2 is different from the material of the stress control unit dielectric layer 27 in the

stress control units

6 and 7.

In the present embodiment, as the dielectric layer 27 for the stress control unit, a material that is easily compressed and contracted in the electric field direction by applying a voltage to the first and second

stress control electrodes

9a and 9b is used. For example, a material having a condition that the elastic modulus of the dielectric layer 26 of the variable capacitance element body 2 is larger than the elastic modulus of the stress control unit dielectric layer 27 in the

stress control units

6 and 7 can be used. In addition, a material in which the Poisson's ratio of the dielectric layer 26 of the variable capacitance element body 2 is smaller than the Poisson's ratio of the stress control unit dielectric layer 27 in the

stress control units

6 and 7 can be used. By using the material under such conditions, more tensile stress can be applied to the variable capacitance element body 2, and the capacitance Cac of the variable capacitance element body 2 can be increased more.

In addition, the variable capacitance element 25 of the present embodiment is formed by the steps shown in FIGS. 21A to 21D, and portions corresponding to the dielectric material film 22 of FIGS. 21A to 21D in the

stress control units

6 and 7 are formed. The material may have a larger elastic modulus than the stress control part dielectric layer 27. As described above, the portions surrounding the first and second

stress control electrodes

9a and 9b in the

stress control portions

6 and 7 are filled with a material having a large elastic modulus, so that the dielectric material film 22 formed in the surroundings is formed. Play the role of a beam. Thereby, tensile stress can be more effectively generated in the variable capacitor element body 2. In the

stress control units

6 and 7, the material of the dielectric layer other than the stress control unit dielectric layer 27 sandwiched between the first and second

stress control electrodes

9a and 9b is used as the stress control unit dielectric layer. It is good also as a material which has an elastic modulus larger than the elastic modulus of 27.

In addition, as the dielectric layer 27 for the stress control unit in the

stress control units

6 and 7, a material that contracts in the electric field direction (for example, PZT) may be used. By doing so, more tensile stress can be given to the variable capacitance element body 2, and as a result, the capacitance Cac of the variable capacitance element body 2 can be increased more with a small control voltage.

Also in the variable capacitance elements according to the first and second embodiments described above, a variable capacitance element having high mechanical strength can be obtained by using the manufacturing method shown in FIGS. 21A to 21D. In this case as well, as described above, it is preferable to select the material of the dielectric material film 22 so that the portions surrounding the first and second

stress control electrodes

9a and 9b are filled with a material having a large elastic modulus. . By using such a material, the dielectric material film 22 formed around the first and second

stress control electrodes

9a and 9b serves as a beam, so that a larger tensile stress can be applied to the variable capacitor element body 2. Can be generated.

In the variable capacitive elements according to the first to third embodiments described above, the variable capacitive element electrode constituting the variable capacitive element body is configured to be laminated in plural layers. However, the variable capacitive element body sandwiches the dielectric layer. It is sufficient that at least one pair of variable capacitance element electrodes is configured. That is, the number of electrodes of the variable capacitance element body can be variously changed as long as a desired capacitance can be obtained.

In the variable capacitance elements according to the first to third embodiments described above, the stress control unit is configured by sandwiching the variable capacitance element body. However, the stress control is performed only in one direction of the variable capacitance element body. It is good also as an example which comprises a part. Also in this case, as shown in FIG. 4, the capacitance of the variable capacitance element body can be increased by applying the control voltage. In addition, the variable capacitor element electrode and the stress control electrode are stacked. However, the stress control unit may be provided on the side surface of the variable capacitor element body in the direction orthogonal to the stacking direction of the variable capacitor element electrode. .

In the first to third embodiments described above, the stress control unit is configured by laminating a plurality of first and second stress control electrodes through the dielectric layer for the stress control unit. The configuration is not limited as long as a tensile stress can be applied to the capacitive element body. For example, it is possible to configure the stress control unit with a piezoelectric element or the like. When the stress control unit is configured by a piezoelectric element, the electrostatic capacity of the capacitive element body can be increased by applying tensile stress to the dielectric layer of the capacitive element body by the piezoelectric element. In addition, a tensile stress may be applied to the dielectric layer of the capacitor element body using magnetic force. Further, the present disclosure is not limited to the above-described embodiments, and various changes and combinations are possible.

In the first to third embodiments described above, a ferroelectric material is used as a material for forming the dielectric layer of the capacitive element body, and the variable capacitive element is used. However, the capacitance of the capacitive element body is applied with voltage. The present disclosure can also be applied to a capacitor element that does not change depending on the case. In this case, the capacitance of the capacitive element body can be changed by controlling the stress control voltage. Therefore, the entire capacitive element has a function as a variable capacitive element.

In addition, by configuring the stress control unit in a capacitive element whose capacitance does not change due to the application of voltage, it becomes possible to match the capacitance values among a plurality of capacitive elements. Thereby, when such a capacitive element is used for the circuit of an electronic device, the dispersion | variation in the performance of an electronic device can be suppressed.

In the first to third embodiments described above, a ferroelectric material is used as a material for forming the dielectric layer of the capacitor element body, and the ferroelectric material has a characteristic of expanding in the electric field direction when a voltage is applied. However, the present disclosure can be adapted to and applied to a dielectric material having a characteristic of contracting in the electric field direction when a voltage is applied. That is, when using, for example, the above-described PZT (lead zirconate titanate) for the capacitor element body, by applying a control voltage to the stress control unit to apply compressive stress to the capacitor element body, Capacitance can be increased. For example, in order to generate the compressive stress, the stress control unit may be extended in the electric field direction of the capacitive element body by applying a control voltage to the stress control unit.

Note that the capacitance C (F) of the capacitive element suitable for the present disclosure also depends on the frequency f (Hz) to be used. The present disclosure is suitable for a capacitor element having a capacitance C (F) in which the impedance Z (ohm) (Z = 1 / 2πfc) is 2 ohms or more, preferably 15 ohms or more, and more preferably 100 ohms or more.

<4. Fourth Embodiment: Resonant Circuit>
Next, a resonant circuit according to the fourth embodiment of the present disclosure will be described. The present embodiment is an example in which the capacitive element of the present disclosure is applied to a resonance circuit, and particularly shows an example in which the variable capacitive element 1 in the first embodiment is applied. Moreover, in this embodiment, the example which used the resonance circuit for the non-contact IC card is shown.

FIG. 24 is a block configuration diagram of a reception system circuit unit of the non-contact IC card 50 using the resonance circuit of the present embodiment. In this embodiment, in order to simplify the description, a signal transmission system (modulation system) circuit unit is omitted. The configuration of the transmission system circuit unit is the same as that of a conventional non-contact IC card or the like. Also, in FIG. 24, parts corresponding to those in FIG.

The non-contact IC card includes a receiving unit 71 (antenna), a rectifying unit 72, and a signal processing unit 73 as shown in FIG.

The receiving unit 71 is constituted by a resonance circuit including a resonance coil 74 and a resonance capacitor 75, and receives a signal transmitted from the R / W (not shown) of the non-contact IC card 50 by this resonance circuit. In FIG. 24, the resonance coil 74 is divided into an inductance component 74a (L) and a resistance component 74b (r: about several ohms).

In the resonant capacitor 75, a capacitor 75a having a capacitance Co and a variable capacitance element body 2 whose capacitance Cv changes according to the voltage value (reception voltage value) of the received signal are connected in parallel. That is, in the present embodiment, the variable capacitance element body 2 is connected in parallel to a conventional antenna (a resonance circuit including a resonance coil 74 and a capacitor 75a). The variable capacitance element body 2 is configured to be incorporated in the variable capacitance element 1 having the

stress control units

6 and 7, as shown in FIG.

As the capacitor 75a, a capacitor formed of a paraelectric material is used as in the conventional antenna. The capacitor 75a made of a paraelectric material has a low relative dielectric constant, and its capacitance hardly changes regardless of the type of input voltage (AC or DC) and its voltage value. Therefore, the capacitor 75a has a very stable characteristic with respect to the input signal. In the conventional antenna, in order to prevent the resonance frequency of the antenna from shifting, a capacitor formed of a paraelectric material having high stability with respect to such an input signal is used.

In the actual circuit, there is a capacitance variation (about several pF) of the receiving unit 71 due to variations in the inductance component L of the resonance coil 74 and parasitic capacitance of the input terminal of the integrated circuit in the signal processing unit 73. The amount of change differs for each non-contact IC card 50. Therefore, in the present embodiment, in order to suppress (correct) these effects, the capacitor Co is appropriately adjusted by trimming the electrode pattern of the capacitor 75a.

The rectifier 72 is constituted by a half-wave rectifier circuit including a rectifier diode 76 and a rectifier capacitor 77, and rectifies and outputs the AC voltage received by the receiver 71 to a DC voltage.

The signal processing unit 73 is mainly composed of an integrated circuit (LSI: Large Scale Integration) of semiconductor elements, and demodulates the AC signal received by the receiving unit 71. The LSI in the signal processing unit 73 is driven by a DC voltage supplied from the rectifying unit 72. Note that the same LSI as a conventional non-contact IC card can be used.

In this embodiment, since the variable capacitance element used in the receiving unit is configured by the stress control unit, the capacitance is not only controlled by the control voltage applied to the variable resonance capacitor itself but also by the control voltage applied to the stress control unit. Can be controlled. For this reason, a large variable width can be obtained with a lower voltage. In addition, since the burden of change on the resonance capacitor can be reduced by the increase in the variable width, if the dielectric of the resonance capacitor is thickened, the withstand voltage is improved and a larger AC voltage can be handled.

In the present embodiment, the variable capacitor of the first embodiment is used as the variable capacitor of the resonance circuit. However, the variable capacitor of the second embodiment or the third embodiment may be used. . Further, as the circuit configuration for driving the variable capacitance element 1, the configuration shown in FIGS. 2A and 2B is applied, but the circuit configuration of FIGS. 12 to 19 may be applied.

Incidentally, the variable capacitance element of the present disclosure shown in the first to third embodiments can be applied to various electronic devices. When applied to an electronic device, for example, the variable capacitance element of the present disclosure can be incorporated and used in a communication system, a wireless charging system including a power feeding device and a power receiving device, a power supply device, and the like. Hereinafter, a communication system, a wireless charging system, and a power supply device configured using the variable capacitance element of the present disclosure are shown, and electronic devices using them are exemplified.

<5. Fifth Embodiment: Communication System>
FIG. 25 illustrates a schematic configuration diagram of a communication system according to the fifth embodiment of the present disclosure. The communication system 200 according to the present embodiment includes a transmission device 201 and a reception device 202 that perform non-contact communication. The communication system 200 of the present embodiment is a communication system that combines a non-contact IC card standard represented by Felica (registered trademark) and a near field communication (NFC) standard, for example. That is, the receiving device 202 constituting the communication system 200 of this embodiment corresponds to the non-contact IC card 50 shown in the fourth embodiment. In this embodiment, the signal processing unit 73 of the non-contact IC card 50 The configuration is described in more detail. In FIG. 25, the wiring related to power supply is indicated by a broken-line arrow.

First, the transmission apparatus 201 will be described. The transmission device 201 has a reader / writer function for reading and writing data without contact with the reception device 202, and includes a primary side antenna unit (transmission side antenna unit) 203, a transmission side system control unit 209, a modulation circuit 207, A demodulation circuit 208 is provided. Furthermore, the transmission apparatus 201 of this embodiment includes a transmission signal unit 205, a variable impedance matching unit 204, and a transmission / reception control unit 206.

The primary antenna unit 203 has the same configuration as that of the receiving unit 71 shown in the fourth embodiment. That is, although not shown, the primary side antenna unit 203 is configured by a resonance circuit including a resonance coil and a resonance capacitor, and the resonance capacitor includes the variable capacitance element shown in the first to third embodiments. It is said that. The primary antenna unit 203 radiates a transmission signal having a desired frequency by the resonance circuit and receives a response signal from the receiving device 202 described later.

The transmission-side system control unit 209 generates control signals for various controls according to external commands and built-in programs, controls the modulation circuit 207 and the transmission / reception control unit 206, and generates transmission data corresponding to the commands. And supplied to the modulation circuit 207. The transmission-side system control unit 209 performs predetermined processing based on the response data demodulated by the demodulation circuit 208.

The modulation circuit 207 modulates the transmission data input from the transmission-side system control unit 209 and sends the modulated transmission data to the transmission signal unit 205. The demodulation circuit 208 acquires the response signal received by the primary antenna unit 203 via the variable impedance matching unit 204, and demodulates the response signal. Then, the demodulation circuit 208 supplies the demodulated response data to the transmission side system control unit 209.

The transmission signal unit 205 modulates a carrier signal having a desired frequency (13.56 MHz) with the transmission data output from the modulation circuit 207, and sends the modulated carrier signal to the variable impedance matching unit 204.
The variable impedance matching unit 204 is a circuit that performs impedance matching between the transmission signal unit 205 and the primary antenna unit 203. Although not shown in FIG. 25, the variable impedance matching unit 204 shown in the first to third embodiments is used. It is a circuit including the disclosed variable capacitance element.

The transmission / reception control unit 206 monitors the communication state such as the transmission voltage and transmission current of the carrier signal transmitted from the transmission signal unit 205 to the variable impedance matching unit 204 and controls the variable impedance matching unit 204 and the primary antenna unit 203. . At this time, the transmission / reception control unit 206 optimizes the impedance matching between the transmission signal unit 205 and the primary side antenna unit 203 and the resonance frequency of the primary side antenna unit 203. Specifically, the impedance and the resonance frequency are adjusted by controlling the capacitances of the variable capacitance elements (not shown) of the present disclosure constituting the variable impedance matching unit 204 and the primary antenna unit 203 by the transmission / reception control unit 206. .

Next, the receiving device 202 will be described. The receiving device 202 constitutes a non-contact IC card that is a data carrier. The receiving device 202 includes a secondary side antenna unit (reception side antenna unit) 210, a rectification unit 211, a constant voltage unit 212, a reception control unit 213, a demodulation circuit 217, a reception side system control unit 214, a modulation circuit 216, and a battery 215. Prepare.

The secondary antenna unit 210 has the same configuration as that of the receiving unit 71 shown in the fourth embodiment. That is, although not shown, the secondary side antenna unit 210 includes a resonance circuit including a resonance coil and a resonance capacitor, and the resonance capacitor is the one disclosed in the first to third embodiments. The variable capacitance element is provided. The secondary antenna unit 210 is a part that communicates with the transmission device 201 by electromagnetic coupling, receives a magnetic field generated by the primary antenna unit of the transmission device 201, and receives a transmission signal from the transmission device 201.

The rectifying unit 211 is configured by a half-wave rectifier circuit including, for example, a rectifying diode and a rectifying capacitor, and rectifies and outputs AC power received by the secondary antenna unit 210 to DC power.
The constant voltage unit 212 performs voltage fluctuation (data component) suppression processing and stabilization processing on the electrical signal supplied from the rectifying unit 211, and outputs the processed DC power. The DC power output via the rectifying unit 211 and the constant voltage unit 212 is used as a power source for operating the IC in the receiving device 202.

The reception control unit 213 determines the size of the reception signal, the voltage / current phase, and the like, and controls the resonance characteristics of the secondary antenna unit 210 to optimize the resonance frequency during reception. Specifically, the resonance frequency is adjusted by controlling the capacitance of the variable capacitance element (not shown) of the present disclosure constituting the secondary antenna unit 210 by the reception control unit 213.

The demodulation circuit 217 demodulates the reception signal received by the secondary side antenna unit 210 and sends the demodulated signal to the reception side system control unit 214.
Based on the signal demodulated by the demodulation circuit 217, the reception-side system control unit 214 determines the contents thereof, performs necessary processing, and controls the modulation circuit 216 and the reception control unit 213.
The modulation circuit 216 modulates the reception carrier according to the result (contents of the demodulated signal) determined by the reception-side system control unit 214, and thereby transmits a response signal transmitted from the secondary-side antenna unit 210 to the primary-side antenna unit 203 Generate.

The battery 215 supplies power to the receiving system control unit 214. The battery 215 is charged by connecting to the external power source 219. As described above, the receiving device 202 according to the present embodiment has a built-in battery to which power is supplied from the external power source 219, and thus can supply more stable power than the power output through the constant voltage unit 212. Stable operation is possible.

In the communication system 200 of the present embodiment, data communication is performed in a non-contact manner via electromagnetic coupling between the primary side antenna unit 203 of the transmission device 201 and the secondary side antenna unit 210 of the reception device 202. Therefore, in this embodiment, in order to perform efficient communication in the transmission device 201 and the reception device 202, the resonance circuits of the primary side antenna unit 203 and the secondary side antenna unit 210 have the same carrier frequency (13. 56 MHz).

And in this embodiment, the variable capacity element of this indication is used for primary side antenna part 203, secondary side antenna part 210, and variable impedance matching part 204, and the capacity can be increased or decreased. Thereby, it is possible to optimize the characteristics by keeping the resonance frequency and the impedance matching characteristics optimal.

In addition, since the variable capacitance element of the present disclosure is incorporated in the resonance capacitor of the resonance circuit that constitutes the primary side antenna unit 203 and the secondary side antenna unit 210, the respective resonance frequencies can always be maintained optimally. For this reason, even if the reception resonance frequency and / or the transmission resonance frequency is shifted due to various factors, the shift of the resonance frequency can be easily adjusted in its own device, and stable communication characteristics can be obtained.

<6. Sixth Embodiment: Wireless Charging System>
Next, a wireless charging system according to the sixth embodiment of the present disclosure will be described. FIG. 26 is a schematic configuration diagram of the wireless charging system 220 of the present embodiment. The wireless charging system 220 of the present embodiment is a device for supplying power (charging) wirelessly (contactlessly), and electromagnetic induction, magnetic field resonance, etc. can be applied as a wireless system. In FIG. 26, parts corresponding to those in FIG. In the present embodiment, the transmission device 201 constitutes a power supply device that supplies power to a desired electronic device in a contactless manner, and the reception device 221 is supplied with power as represented by a portable device. The power receiving apparatus is configured.

In the present embodiment, the receiving device 221 is configured such that the constant voltage unit 212 of the receiving device 202 in the communication system 200 according to the fifth embodiment is a charge control unit 218. The charging control unit 218 supplies the electric signal supplied from the rectifying unit 211 to the battery 215 to charge the battery 215, and supplies the electric signal to the reception control unit 213 as power for operating the reception control unit 213. In addition, the charging control unit 218 monitors the charging status and outputs the monitoring result to the receiving-side system control unit 214. In the present embodiment, the charging control unit 218 can be charged by connecting an external power source 219 from the outside.

In such a wireless charging system 220, an electromagnetic wave for power transmission is radiated from the primary side antenna unit (feeding side antenna unit) 203 based on a signal generated by the transmission side system control unit 209, and the electromagnetic wave is transmitted to the secondary side. It is received by the side antenna unit (power receiving side antenna unit) 210. Then, the signal received by the secondary antenna unit 210 is converted into DC power by the rectifying unit 211, and the DC power is charged to the battery 215 via the charging control unit 218.

Also in the wireless charging system 220 of the present embodiment, the signal transmitted from the transmitter 201 side is received by the secondary antenna unit 210, and the received signal is demodulated by the demodulation circuit 217. Then, the content of the demodulated data is judged by the reception side system control unit 214, and a response is made by modulating the reception carrier by the modulation circuit 216 according to the result. This series of recognition processes can avoid power transmission to out-of-system devices and metals. In order to perform charging for a long time, such recognition processing is performed intermittently as appropriate to ensure safety, and when it is determined that the recognition processing is correct, the transmission signal is not modulated for power transmission. Output.

Further, in the wireless charging system 220 of the present embodiment, the charging status is monitored by the charging control unit 218 of the receiving device 221 as described above, via the receiving-side system control unit 214 so as to obtain an optimal charging current. Information on the charging status is sent to the transmitting device 201. The information returned from the receiving device 221 is demodulated by the demodulating circuit 208 of the transmitting device 201, and then the content is judged, and the transmitting side system control unit 209 executes necessary processing.

Otherwise, the same processing as the communication system according to the fifth embodiment is performed. Also in this embodiment, the variable capacitance element of the present disclosure is incorporated in the variable impedance matching unit 204, the primary antenna unit 203, and the secondary antenna unit 210, and the same effects as those of the fifth embodiment are obtained. be able to.

<7. Seventh Embodiment: Power Supply Device>
Next, a power supply device according to a seventh embodiment of the present disclosure will be described. FIG. 27 is a schematic configuration diagram showing the power supply device 230 of the present embodiment. In the present embodiment, a power supply device that steps down the voltage (AC 100 V) of the commercial power supply 236 via a power transformer 235 that is a power supply unit will be described as an example.

The power supply device 230 of this embodiment includes a power supply transformer 235, a variable impedance 231, a rectifier circuit 232, an error amplifier 234, a constant voltage circuit 233, a first reference voltage power supply 239, and a second reference voltage power supply 238.

The power transformer 235 includes a primary transformer 235a and a secondary transformer 235b. One end of the AC 100V commercial power source 236 is connected to one end of the primary side transformer 235a, and the other end of the commercial power source 236 is connected to the other end of the primary side transformer 235a. A variable impedance 231 is connected to one end of the secondary transformer 235b, and a rectifier circuit 232 is connected to the other end. The power transformer 235 steps down the voltage of the commercial power source 236 at a rate corresponding to the turn ratio between the primary transformer 235a and the secondary transformer 235b.

Although not shown, the variable impedance 231 includes the variable capacitance element of the present disclosure shown in the first to third embodiments. The variable impedance 231 includes the secondary transformer 235b, the rectifier circuit 232, It is connected to the error amplifier 234. The variable impedance 231 increases or decreases the AC voltage input from the secondary transformer 235 b by increasing or decreasing the capacitance of the variable capacitance element to change the impedance, and supplies the increased or decreased AC voltage to the rectifier circuit 232.

The rectifier circuit 232 is configured by a half-wave rectifier circuit including, for example, a rectifier diode and a rectifier capacitor. In the rectifier circuit 232, the variable impedance 231 is connected to the anode side of the rectifier diode, and the terminal on the opposite side to the connection side of the variable impedance 231 of the secondary transformer 235b is connected to the cathode side. The output terminal of the rectifier circuit 232 is connected to the constant voltage circuit 233 and to the error amplifier 234. The rectifier circuit 232 rectifies the AC voltage input from the variable impedance 231 into a DC voltage and supplies the DC voltage to the error amplifier 234 and the constant voltage circuit 233.

The constant voltage circuit 233 is connected to the rectifier circuit 232. The first reference voltage power source 239 is connected to the other terminal of the constant voltage circuit 233, and the other terminal is connected to the load 237. The constant voltage circuit 233 compares the reference voltage V _ref 1 supplied from the first reference voltage power source 239 with the DC voltage input from the rectifier circuit 232 and supplies a constant DC voltage to the load 237.

The error amplifier 234 is connected to the second reference voltage power source 238, the rectifier circuit 232, and the variable impedance 231. The error amplifier 234 controls the impedance of the variable impedance 231 by comparing the DC voltage rectified by the rectifier circuit 232 with the reference voltage V _ref 2 supplied from the second reference voltage power source 238. Usually, the reference voltage V _ref 2 supplied from the second reference voltage power source 238 is set to be about 2V higher than the reference voltage V _ref 1 supplied from the first reference voltage power source 239.

In the power supply device 230 of the present embodiment, the voltage stepped down at a ratio corresponding to the turn ratio of the primary transformer 235a and the secondary transformer 235b of the power transformer 235 is rectified, and the load is reduced by the voltage drop type constant voltage circuit 233. A constant voltage can be provided to 237.

By the way, in such a power supply device 230, the voltage output from the rectifier circuit 232 changes due to the increase / decrease of the load current or the voltage change of the primary transformer 235a. In contrast, in the present embodiment, when the load current is large and the AC voltage of the secondary transformer 235b is lowered, the impedance is lowered, the voltage of the commercial power supply 236 is increased, and the AC voltage of the secondary transformer 235b is raised. If so, increase the impedance. As a result, the AC voltage input to the rectifier circuit 232 can be stabilized, and the input power of the constant voltage circuit 233 can be controlled stably.

In such a power supply device 230, the voltage drop type constant voltage circuit 233 stabilizes the voltage by increasing or decreasing its own voltage drop so that the reference voltage V _ref 1 and the voltage applied to the load 237 are the same. I am trying. This voltage drop accounts for most of the power loss in the constant voltage circuit 233 constituting the power supply device 230. Therefore, ideally, the loss can be minimized if the input voltage of the constant voltage circuit 233 can be controlled to be the minimum operating voltage of the constant voltage circuit 233.

In the present embodiment, the variable impedance 231 including the variable capacitance element of the present disclosure described above is inserted between the secondary-side transformer 235b and the rectifier circuit 232, and the impedance is changed by increasing or decreasing the capacitance of the variable capacitance element. AC voltage can be increased or decreased. Thereby, the input voltage value of the constant voltage circuit 233 can be controlled to be a value near the minimum operating voltage of the constant voltage circuit 233, and the power loss in the constant voltage circuit 233 can be reduced.

Also, in the conventional general voltage drop type constant voltage circuit, the voltage is stabilized by a variable resistor, so that power loss occurs. On the other hand, in this embodiment, since the voltage drop is caused by changing the capacitance of the variable capacitance element configured in the variable impedance 231, no resistance component occurs and no power loss occurs.

In the present embodiment, the power supply device 230 using the commercial power supply 236 and the power transformer 235 has been described as an example, but the same configuration can be adopted when considered as a SW power supply (switch power supply). For example, if the input is a switching frequency of 100 KHz, the same circuit can be configured. In this embodiment, the output voltage is one system. However, if there are a plurality of transformer output terminals, it can be used as a plurality of power supply systems.

The above-described communication system, wireless charging system, and power supply device can be applied to various electronic devices in an appropriate combination. For example, a communication system and a wireless charging system may be combined. Examples of such electronic devices include a mobile phone, a smartphone, a tablet PC (Personal Computer), a notebook PC, a remote controller, a wireless speaker, a camcorder, and a digital Examples include cameras, Walkman (registered trademark), and 3D glasses. A communication system and a power supply device may be combined. Examples of such electronic devices include a tablet PC, a notebook PC, a desktop PC, a printer, a projector, a liquid crystal TV (Television), a refrigerator, a DVD (Digital Versatile Disk). ) / BD (Blu-ray Disk: registered trademark) player, DVD / BD recorder, and electric vehicle. In addition, a wireless charging system and a power supply device may be combined. Examples of such an electronic device include a notebook PC, a portable TV, a radio, a radio cassette recorder, an electric toothbrush, an electric shaver, an iron, and an electric vehicle. It is done. In addition, a communication system, a wireless charging system, and a power supply device may be combined. Examples of such electronic devices include notebook PCs, portable TVs, radios, radio cassette recorders, and electric vehicles.
When combining these devices, a control unit for controlling each device may be provided for each device, and a plurality of control units that can be used in common among the devices are configured integrally. May be.

And in these electronic devices, since the above-described variable capacitance element of the present disclosure is incorporated in the communication system, the wireless charging system, and the power supply device, the reliability of the product is improved. In the fifth to seventh embodiments described above, the variable capacitance elements shown in the first to third embodiments are incorporated in the respective devices. However, according to the first to third embodiments. It is good also as a structure incorporating the element which combined the variable capacity element, and can change suitably.

Moreover, this indication can take the following structures.
(1)
A capacitive element body composed of a dielectric layer and at least one pair of capacitive element electrodes that sandwich the dielectric layer and generate a desired electric field in the dielectric layer;
A capacitive element configured to control a stress generated in the dielectric layer of the capacitive element body and increase a capacitance of the capacitive element body.
(2)
The stress control unit includes a stress control unit dielectric layer and a plurality of stress control electrodes stacked in the stress control unit dielectric layer,
The capacitive element according to (1), wherein a capacitance of the capacitive element body is increased by applying a desired control voltage to the stress control electrode.
(3)
The said stress control part is laminated | stacked on the thickness direction of the dielectric material layer of the said capacitive element main body. The capacitive element as described in (1) or (2).
(4)
The capacitive element according to any one of (1) to (3), wherein the stress control unit is stacked in a thickness direction of a dielectric layer of the capacitive element body with the capacitive element body interposed therebetween.
(5)
The capacitive element according to any one of (2) to (4), wherein the capacitive element electrode and the stress control electrode are stacked in parallel with each other.
(6)
The capacitor element according to any one of (2) to (5), wherein the dielectric layer is made of a ferroelectric material whose capacitance changes according to a control voltage.
(7)
The capacitive element according to any one of (2) to (6), wherein the stress control electrode is electrically separated from the capacitive element electrode.
(8)
The capacitive element according to any one of (1) to (7), wherein a plurality of capacitive element electrodes are laminated via a dielectric layer in the capacitive element body.
(9)
The capacitive element according to any one of (2) to (8), wherein a thickness of the stress control dielectric layer of the stress control unit is configured to be thinner than a thickness of the dielectric layer of the capacitive element body.
(10)
The two stress control units stacked with the capacitive element body sandwiched therebetween are connected to different control voltage power sources, respectively, and control voltages supplied from the corresponding control voltage power sources are supplied to the two stress control units. The capacitive element according to any one of (4) to (9), which is applied independently.
(11)
The two stress control units stacked with the capacitive element body interposed therebetween are connected in series or in parallel via two control voltage power supplies, and the electric field directions in the two stress control units are the same or opposite. The capacitive element according to any one of (4) to (10).
(12)
The two stress control units stacked with the capacitive element body interposed therebetween are connected in series or in parallel via one control voltage power source, and the electric field directions in the two stress control units are the same or opposite. The capacitive element according to any one of (4) to (11).
(13)
A capacitor element electrode is formed by applying a conductive paste on a dielectric sheet to be a dielectric layer so as to have a desired electrode shape, and a dielectric material is formed on the dielectric sheet so as to embed the periphery of the capacitor element electrode. Forming a film;
Forming a laminated body to be a capacitive element body by laminating a plurality of dielectric sheets on which the capacitive element electrodes are formed; and
A step of firing the laminated body to form a capacitive element body in which a plurality of capacitive element electrodes are laminated via a dielectric layer;
Forming a stress control unit for controlling the stress generated in the dielectric layer of the capacitive element body and increasing the capacitance of the capacitive element body by bonding to the capacitive element body. Method.
(14)
The stress control unit forms a stress control electrode by applying a conductive paste on the dielectric sheet to be a dielectric layer for the stress control unit to form a desired electrode shape, and embeds the periphery of the stress control electrode. A step of forming a dielectric material film on the dielectric sheet, and a step of forming a laminate that becomes a stress control unit by laminating a plurality of dielectric sheets on which the stress control electrodes are formed. Formed,
The firing process is performed after laminating a laminated body that becomes the stress control unit and a laminated body that becomes the capacitive element body, thereby integrating the capacitive element body and the stress control unit. Manufacturing method of capacitive element.
(15)
Capacitor element body composed of a dielectric layer and at least one pair of capacitor element electrodes that sandwich the dielectric layer and generate a desired electric field in the dielectric layer, and generated in the dielectric layer of the capacitor element body A resonance capacitor including a capacitive element configured to have a stress control unit that controls stress to increase and increases a capacitance of the capacitive element body;
A resonance circuit comprising: a resonance coil connected to the resonance capacitor.
(16)
The stress control unit includes a stress control unit dielectric layer and a plurality of stress control electrodes stacked in the stress control unit dielectric layer,
The resonant circuit according to (15), wherein a capacitance of the capacitive element body is increased by applying a desired control voltage to the stress control electrode.
(17)
The resonance circuit according to (15) or (16), wherein the stress control unit is stacked in a thickness direction of a dielectric layer of the capacitive element body with the capacitive element body interposed therebetween.
(18)
The two stress control units stacked with the capacitive element body interposed therebetween are connected to different control voltage power sources, and the two stress control units have independent control voltages supplied from the corresponding control voltage power sources. The resonance circuit according to (17).
(19)
The two stress control units stacked with the capacitive element body interposed therebetween are connected in series or in parallel via two control voltage power supplies, and the electric field directions in the two stress control units are the same or opposite. The resonance circuit according to (17) or (18).
(20)
The two stress control units stacked with the capacitive element body interposed therebetween are connected in series or in parallel via one control voltage power source, and the electric field directions in the two stress control units are the same or opposite. The resonance circuit according to (17) or (18).
(21)
A first capacitive element body comprising a first dielectric layer and at least one pair of first capacitive element electrodes that sandwich the first dielectric layer and generate a desired electric field in the first dielectric layer; A first capacitor configured to include a first stress control unit configured to control a stress generated in the first dielectric layer of the first capacitor element body and to increase a capacitance of the first capacitor element body; A transmission device including a transmission-side antenna unit having a first resonance capacitor including an element and a first resonance coil connected to the first resonance capacitor;
A second capacitive element body comprising a second dielectric layer and at least one pair of second capacitive element electrodes that sandwich the second dielectric layer and generate a desired electric field in the second dielectric layer; A second capacitor configured to include a second stress control unit configured to control a stress generated in the second dielectric layer of the second capacitor element body and increase a capacitance of the second capacitor element body. A receiving system comprising: a receiving-side antenna unit having a second resonant capacitor including an element and a second resonant coil connected to the second resonant capacitor.
(22)
A first capacitive element body comprising a first dielectric layer and at least one pair of first capacitive element electrodes that sandwich the first dielectric layer and generate a desired electric field in the first dielectric layer; A first capacitor configured to include a first stress control unit configured to control a stress generated in the first dielectric layer of the first capacitor element body and to increase a capacitance of the first capacitor element body; A power feeding device including a power feeding side antenna unit having a first resonant capacitor including an element and a first resonant coil connected to the first resonant capacitor;
A second capacitive element body comprising a second dielectric layer and at least one pair of second capacitive element electrodes that sandwich the second dielectric layer and generate a desired electric field in the second dielectric layer; A second capacitor configured to include a second stress control unit configured to control a stress generated in the second dielectric layer of the second capacitor element body and increase a capacitance of the second capacitor element body. A wireless charging system comprising: a power receiving device including a power receiving side antenna unit having a second resonant capacitor including an element and a second resonant coil connected to the second resonant capacitor.
(23)
A power supply unit;
Capacitor element body composed of a dielectric layer and at least one pair of capacitor element electrodes that sandwich the dielectric layer and generate a desired electric field in the dielectric layer, and generated in the dielectric layer of the capacitor element body And a variable impedance configured to include a resonant capacitor including a capacitive element that includes a stress control unit configured to control a stress to increase and increase a capacitance of the capacitive element body.
(24)
A first capacitive element body comprising a first dielectric layer and at least one pair of first capacitive element electrodes that sandwich the first dielectric layer and generate a desired electric field in the first dielectric layer; A first capacitor configured to include a first stress control unit configured to control a stress generated in the first dielectric layer of the first capacitor element body and to increase a capacitance of the first capacitor element body; A transmission device including a transmission-side antenna unit having a first resonance capacitor including an element and a first resonance coil connected to the first resonance capacitor;
A second capacitive element body comprising a second dielectric layer and at least one pair of second capacitive element electrodes that sandwich the second dielectric layer and generate a desired electric field in the second dielectric layer; A second capacitor configured to include a second stress control unit configured to control a stress generated in the second dielectric layer of the second capacitor element body and increase a capacitance of the second capacitor element body. A receiving device including a receiving-side antenna unit having a second resonance capacitor including an element and a second resonance coil connected to the second resonance capacitor;
An electronic device comprising: a control unit that controls a capacitance of the first capacitive element and the second capacitive element.
(25)
A first capacitive element body comprising a first dielectric layer and at least one pair of first capacitive element electrodes that sandwich the first dielectric layer and generate a desired electric field in the first dielectric layer; A first capacitor configured to include a first stress control unit configured to control a stress generated in the first dielectric layer of the first capacitor element body and to increase a capacitance of the first capacitor element body; A power feeding device including a power feeding side antenna unit having a first resonant capacitor including an element and a first resonant coil connected to the first resonant capacitor;
A second capacitive element body comprising a second dielectric layer and at least one pair of second capacitive element electrodes that sandwich the second dielectric layer and generate a desired electric field in the second dielectric layer; A second capacitor configured to include a second stress control unit configured to control a stress generated in the second dielectric layer of the second capacitor element body and increase a capacitance of the second capacitor element body. A power receiving device including a power receiving side antenna unit having a second resonant capacitor including an element and a second resonant coil connected to the second resonant capacitor;
An electronic device comprising: a control unit that controls a capacitance of the first capacitive element and the second capacitive element.
(26)
A power supply unit;
Capacitor element body composed of a dielectric layer and at least one pair of capacitor element electrodes that sandwich the dielectric layer and generate a desired electric field in the dielectric layer, and generated in the dielectric layer of the capacitor element body A variable impedance configured to include a resonant capacitor including a capacitive element that includes a stress control unit configured to control a stress to increase and increase a capacitance of the capacitive element body;
And an electronic device including a control unit that controls the capacitance of the capacitive element.
(27)
A first capacitive element body comprising a first dielectric layer and at least one pair of first capacitive element electrodes that sandwich the first dielectric layer and generate a desired electric field in the first dielectric layer; A first capacitor configured to include a first stress control unit configured to control a stress generated in the first dielectric layer of the first capacitor element body and to increase a capacitance of the first capacitor element body; A transmission device including a transmission-side antenna unit having a first resonance capacitor including an element and a first resonance coil connected to the first resonance capacitor;
A second capacitive element body comprising a second dielectric layer and at least one pair of second capacitive element electrodes that sandwich the second dielectric layer and generate a desired electric field in the second dielectric layer; A second capacitor configured to include a second stress control unit configured to control a stress generated in the second dielectric layer of the second capacitor element body and increase a capacitance of the second capacitor element body. A receiving device including a receiving-side antenna unit having a second resonance capacitor including an element and a second resonance coil connected to the second resonance capacitor;
A third capacitive element body comprising a third dielectric layer and at least one pair of third capacitive element electrodes that sandwich the third dielectric layer and generate a desired electric field in the third dielectric layer; A third capacitor configured to include a third stress control unit that controls a stress generated in the third dielectric layer of the third capacitor element body and increases a capacitance of the third capacitor element body; A power supply apparatus including a power supply side antenna unit having a third resonance capacitor including an element and a third resonance coil connected to the third resonance capacitor;
A fourth capacitive element body comprising a fourth dielectric layer and at least one pair of fourth capacitive element electrodes that sandwich the fourth dielectric layer and generate a desired electric field in the fourth dielectric layer; A fourth capacitor configured to include a fourth stress control unit that controls a stress generated in the fourth dielectric layer of the fourth capacitor element body and increases a capacitance of the fourth capacitor element body; A power receiving device including a power receiving side antenna unit having a fourth resonant capacitor including an element and a fourth resonant coil connected to the fourth resonant capacitor;
An electronic device comprising: a control unit that controls the capacitance of each of the first capacitive element, the second capacitive element, the third capacitive element, and the fourth capacitive element.
(28)
A first capacitive element body comprising a first dielectric layer and at least one pair of first capacitive element electrodes that sandwich the first dielectric layer and generate a desired electric field in the first dielectric layer; A first capacitor configured to include a first stress control unit configured to control a stress generated in the first dielectric layer of the first capacitor element body and to increase a capacitance of the first capacitor element body; A transmission device including a transmission-side antenna unit having a first resonance capacitor including an element and a first resonance coil connected to the first resonance capacitor;
A second capacitive element body comprising a second dielectric layer and at least one pair of second capacitive element electrodes that sandwich the second dielectric layer and generate a desired electric field in the second dielectric layer; A second capacitor configured to include a second stress control unit configured to control a stress generated in the second dielectric layer of the second capacitor element body and increase a capacitance of the second capacitor element body. A receiving device including a receiving-side antenna unit having a second resonance capacitor including an element and a second resonance coil connected to the second resonance capacitor;
A power supply section, a third dielectric layer, and at least one pair of third capacitive element electrodes sandwiching the third dielectric layer and generating a desired electric field in the third dielectric layer A third capacitive element main body, and a third stress control unit that controls a stress generated in the third dielectric layer of the third capacitive element main body and increases a capacitance of the third capacitive element main body. A power supply device including a variable impedance configured to include a third resonant capacitor including a configured third capacitive element, and a capacitance of each of the first capacitive element, the second capacitive element, and the third capacitive element An electronic device including a control unit for controlling.
(29)
A first capacitive element body comprising a first dielectric layer and at least one pair of first capacitive element electrodes that sandwich the first dielectric layer and generate a desired electric field in the first dielectric layer; A first capacitor configured to include a first stress control unit configured to control a stress generated in the first dielectric layer of the first capacitor element body and to increase a capacitance of the first capacitor element body; A power feeding device including a power feeding side antenna unit having a first resonant capacitor including an element and a first resonant coil connected to the first resonant capacitor;
A second capacitive element body comprising a second dielectric layer and at least one pair of second capacitive element electrodes that sandwich the second dielectric layer and generate a desired electric field in the second dielectric layer; A second capacitor configured to include a second stress control unit configured to control a stress generated in the second dielectric layer of the second capacitor element body and increase a capacitance of the second capacitor element body. A power receiving device including a power receiving side antenna unit having a second resonant capacitor including an element and a second resonant coil connected to the second resonant capacitor;
A power supply section, a third dielectric layer, and at least one pair of third capacitive element electrodes sandwiching the third dielectric layer and generating a desired electric field in the third dielectric layer A third capacitive element main body, and a third stress control unit that controls a stress generated in the third dielectric layer of the third capacitive element main body and increases a capacitance of the third capacitive element main body. A power supply device including a variable impedance configured to include a third resonance capacitor including a third capacitance element configured;
An electronic device comprising: a control unit that controls a capacitance of each of the first capacitive element, the second capacitive element, and the third capacitive element.
(30)
A first capacitive element body comprising a first dielectric layer and at least one pair of first capacitive element electrodes that sandwich the first dielectric layer and generate a desired electric field in the first dielectric layer; A first capacitor configured to include a first stress control unit configured to control a stress generated in the first dielectric layer of the first capacitor element body and to increase a capacitance of the first capacitor element body; A transmission device including a transmission-side antenna unit having a first resonance capacitor including an element and a first resonance coil connected to the first resonance capacitor;
A second capacitive element body comprising a second dielectric layer and at least one pair of second capacitive element electrodes that sandwich the second dielectric layer and generate a desired electric field in the second dielectric layer; A second capacitor configured to include a second stress control unit configured to control a stress generated in the second dielectric layer of the second capacitor element body and increase a capacitance of the second capacitor element body. A receiving device including a receiving-side antenna unit having a second resonance capacitor including an element and a second resonance coil connected to the second resonance capacitor;
A third capacitive element body comprising a third dielectric layer and at least one pair of third capacitive element electrodes that sandwich the third dielectric layer and generate a desired electric field in the third dielectric layer; A third capacitor configured to include a third stress control unit that controls a stress generated in the third dielectric layer of the third capacitor element body and increases a capacitance of the third capacitor element body; A power supply apparatus including a power supply side antenna unit having a third resonance capacitor including an element and a third resonance coil connected to the third resonance capacitor;
A fourth capacitive element body comprising a fourth dielectric layer and at least one pair of fourth capacitive element electrodes that sandwich the fourth dielectric layer and generate a desired electric field in the fourth dielectric layer; A fourth capacitor configured to include a fourth stress control unit that controls a stress generated in the fourth dielectric layer of the fourth capacitor element body and increases a capacitance of the fourth capacitor element body; A power receiving device including a power receiving side antenna unit having a fourth resonant capacitor including an element and a fourth resonant coil connected to the fourth resonant capacitor;
The power supply unit includes a fifth dielectric layer, and at least one pair of fifth capacitive element electrodes that sandwich the fifth dielectric layer and generate a desired electric field in the fifth dielectric layer. A fifth capacitive element main body, and a fifth stress control unit that controls a stress generated in the fifth dielectric layer of the fifth capacitive element main body and increases a capacitance of the fifth capacitive element main body. A power supply device including a variable impedance configured to include a fifth resonant capacitor including a fifth capacitive element configured as follows:
An electronic device comprising: a control unit that controls the capacitance of each of the first capacitive element, the second capacitive element, the third capacitive element, the fourth capacitive element, and the fifth capacitive element.
(31)
Capacitor element body composed of a dielectric layer and at least one pair of capacitor element electrodes that sandwich the dielectric layer and generate a desired electric field in the dielectric layer, and generated in the dielectric layer of the capacitor element body A resonance capacitor including a capacitive element configured to have a stress control unit that controls stress to increase and increases a capacitance of the capacitive element body;
An electronic device comprising: a resonance coil connected to the resonance capacitor.

DESCRIPTION OF SYMBOLS 1 ... Variable capacitance element, 2 ... Variable capacitance element main body, 3a ... 1st signal terminal, 3b ... 2nd signal terminal, 4 ... Dielectric layer, 5a ... 1st 1 variable capacitance element electrode, 5b ... second variable capacitance element electrode, 6 ... stress control unit, 7 ... stress control unit, 8a ... first control terminal, 8b ... first 2 control terminals, 9a ... first stress control electrode, 9b ... second stress control electrode, 10 ... dielectric layer for stress control part, 20 ... dielectric sheet, 21 ... Conductive paste, 22: Dielectric material film, 24: Variable capacitance element, 26: Dielectric layer, 27: Dielectric layer for stress control unit, 50: Non-contact IC card, 71 ... Receiving unit 72 ... Rectifying unit 73 ... Signal processing unit 74 ... Resonance coil 74a ... Inductance component 74b - resistance component, 75 ... resonant capacitor, 75a ... capacitor, 76 ... rectifying diode, 77 ... rectifying capacitor

Claims

A capacitive element body composed of a dielectric layer and at least one pair of capacitive element electrodes that sandwich the dielectric layer and generate a desired electric field in the dielectric layer;
A capacitive element configured to control a stress generated in the dielectric layer of the capacitive element body and increase a capacitance of the capacitive element body.
The stress control unit includes a stress control unit dielectric layer and a plurality of stress control electrodes stacked in the stress control unit dielectric layer,
The capacitive element according to claim 1, wherein a capacitance of the capacitive element body is increased by applying a desired control voltage to the stress control electrode.
The capacitive element according to claim 1, wherein the stress control unit is stacked in a thickness direction of a dielectric layer of the capacitive element body.
The capacitive element according to claim 1, wherein the stress control unit is stacked in a thickness direction of a dielectric layer of the capacitive element body with the capacitive element body interposed therebetween.
The capacitive element according to claim 2, wherein the capacitive element electrode and the stress control electrode are stacked in parallel with each other.
The capacitive element according to claim 2, wherein the dielectric layer is made of a ferroelectric material whose capacitance changes according to a control voltage.
The capacitive element according to claim 2, wherein the stress control electrode is electrically separated from the capacitive element electrode.
The capacitive element according to claim 1, wherein in the capacitive element body, a plurality of capacitive element electrodes are laminated via a dielectric layer.
The capacitive element according to claim 2, wherein a thickness of the stress control dielectric layer of the stress control unit is configured to be thinner than a thickness of the dielectric layer of the capacitive element body.
The two stress control units stacked with the capacitive element body sandwiched therebetween are connected to different control voltage power sources, respectively, and control voltages supplied from the corresponding control voltage power sources are supplied to the two stress control units. The capacitive element according to claim 4, which is applied independently.
The two stress control units stacked with the capacitive element body interposed therebetween are connected in series or in parallel via two control voltage power supplies, and the electric field directions in the two stress control units are the same or opposite. The capacitive element according to claim 4, wherein the capacitance element is in a direction.
The two stress control units stacked with the capacitive element body interposed therebetween are connected in series or in parallel via one control voltage power source, and the electric field directions in the two stress control units are the same or opposite. The capacitive element according to claim 4, wherein the capacitance element is in a direction.
A capacitor element electrode is formed by applying a conductive paste on a dielectric sheet to be a dielectric layer so as to have a desired electrode shape, and a dielectric material is formed on the dielectric sheet so as to embed the periphery of the capacitor element electrode. Forming a film;
Forming a laminated body to be a capacitive element body by laminating a plurality of dielectric sheets on which the capacitive element electrodes are formed; and
A step of firing the laminated body to form a capacitive element body in which a plurality of capacitive element electrodes are laminated via a dielectric layer;
Forming a stress control unit for controlling the stress generated in the dielectric layer of the capacitive element body and increasing the capacitance of the capacitive element body by bonding to the capacitive element body. Method.
The stress control unit forms a stress control electrode by applying a conductive paste on the dielectric sheet to be a dielectric layer for the stress control unit to form a desired electrode shape, and embeds the periphery of the stress control electrode. A step of forming a dielectric material film on the dielectric sheet, and a step of forming a laminate that becomes a stress control unit by laminating a plurality of dielectric sheets on which the stress control electrodes are formed. Formed,
The said baking process integrates the said capacitive element main body and the said stress control part by performing after laminating | stacking the laminated body which becomes the said stress control part, and the laminated body which becomes the said capacitive element main body. Manufacturing method of capacitive element.
Capacitor element body composed of a dielectric layer and at least one pair of capacitor element electrodes that sandwich the dielectric layer and generate a desired electric field in the dielectric layer, and generated in the dielectric layer of the capacitor element body A resonance capacitor including a capacitive element configured to have a stress control unit that controls stress to increase and increases a capacitance of the capacitive element body;
A resonance circuit comprising: a resonance coil connected to the resonance capacitor.
The stress control unit includes a stress control unit dielectric layer and a plurality of stress control electrodes stacked in the stress control unit dielectric layer,
The resonant circuit according to claim 15, wherein a capacitance of the capacitive element body is increased by applying a desired control voltage to the stress control electrode.
The resonance circuit according to claim 15, wherein the stress control unit is stacked in a thickness direction of a dielectric layer of the capacitive element body with the capacitive element body interposed therebetween.
The two stress control units stacked with the capacitive element body interposed therebetween are connected to different control voltage power sources, and the two stress control units have independent control voltages supplied from the corresponding control voltage power sources. The resonance circuit according to claim 17, which is applied to the resonance circuit.
The two stress control units stacked with the capacitive element body interposed therebetween are connected in series or in parallel via two control voltage power supplies, and the electric field directions in the two stress control units are the same or opposite. The resonance circuit according to claim 17, wherein the resonance circuit is a direction.
The two stress control units stacked with the capacitive element body interposed therebetween are connected in series or in parallel via one control voltage power source, and the electric field directions in the two stress control units are the same or opposite. The resonance circuit according to claim 17, wherein the resonance circuit is a direction.
A first capacitive element body comprising a first dielectric layer and at least one pair of first capacitive element electrodes that sandwich the first dielectric layer and generate a desired electric field in the first dielectric layer; A first capacitor configured to include a first stress control unit configured to control a stress generated in the first dielectric layer of the first capacitor element body and to increase a capacitance of the first capacitor element body; A transmission device including a transmission-side antenna unit having a first resonance capacitor including an element and a first resonance coil connected to the first resonance capacitor;
A second capacitive element body comprising a second dielectric layer and at least one pair of second capacitive element electrodes that sandwich the second dielectric layer and generate a desired electric field in the second dielectric layer; A second capacitor configured to include a second stress control unit configured to control a stress generated in the second dielectric layer of the second capacitor element body and increase a capacitance of the second capacitor element body. A receiving system comprising: a receiving-side antenna unit having a second resonant capacitor including an element and a second resonant coil connected to the second resonant capacitor.
A first capacitive element body comprising a first dielectric layer and at least one pair of first capacitive element electrodes that sandwich the first dielectric layer and generate a desired electric field in the first dielectric layer; A first capacitor configured to include a first stress control unit configured to control a stress generated in the first dielectric layer of the first capacitor element body and to increase a capacitance of the first capacitor element body; A power feeding device including a power feeding side antenna unit having a first resonant capacitor including an element and a first resonant coil connected to the first resonant capacitor;
A second capacitive element body comprising a second dielectric layer and at least one pair of second capacitive element electrodes that sandwich the second dielectric layer and generate a desired electric field in the second dielectric layer; A second capacitor configured to include a second stress control unit configured to control a stress generated in the second dielectric layer of the second capacitor element body and increase a capacitance of the second capacitor element body. A wireless charging system comprising: a power receiving device including a power receiving side antenna unit having a second resonant capacitor including an element and a second resonant coil connected to the second resonant capacitor.
A power supply unit;
Capacitor element body composed of a dielectric layer and at least one pair of capacitor element electrodes that sandwich the dielectric layer and generate a desired electric field in the dielectric layer, and generated in the dielectric layer of the capacitor element body And a variable impedance configured to include a resonant capacitor including a capacitive element that includes a stress control unit configured to control a stress to increase and increase a capacitance of the capacitive element body.
A first capacitive element body comprising a first dielectric layer and at least one pair of first capacitive element electrodes that sandwich the first dielectric layer and generate a desired electric field in the first dielectric layer; A first capacitor configured to include a first stress control unit configured to control a stress generated in the first dielectric layer of the first capacitor element body and to increase a capacitance of the first capacitor element body; A transmission device including a transmission-side antenna unit having a first resonance capacitor including an element and a first resonance coil connected to the first resonance capacitor;
A second capacitive element body comprising a second dielectric layer and at least one pair of second capacitive element electrodes that sandwich the second dielectric layer and generate a desired electric field in the second dielectric layer; A second capacitor configured to include a second stress control unit configured to control a stress generated in the second dielectric layer of the second capacitor element body and increase a capacitance of the second capacitor element body. A receiving device including a receiving-side antenna unit having a second resonance capacitor including an element and a second resonance coil connected to the second resonance capacitor;
An electronic device comprising: a control unit that controls a capacitance of the first capacitive element and the second capacitive element.
A first capacitive element body comprising a first dielectric layer and at least one pair of first capacitive element electrodes that sandwich the first dielectric layer and generate a desired electric field in the first dielectric layer; A first capacitor configured to include a first stress control unit configured to control a stress generated in the first dielectric layer of the first capacitor element body and to increase a capacitance of the first capacitor element body; A power feeding device including a power feeding side antenna unit having a first resonant capacitor including an element and a first resonant coil connected to the first resonant capacitor;
A second capacitive element body comprising a second dielectric layer and at least one pair of second capacitive element electrodes that sandwich the second dielectric layer and generate a desired electric field in the second dielectric layer; A second capacitor configured to include a second stress control unit configured to control a stress generated in the second dielectric layer of the second capacitor element body and increase a capacitance of the second capacitor element body. A power receiving device including a power receiving side antenna unit having a second resonant capacitor including an element and a second resonant coil connected to the second resonant capacitor;
An electronic device comprising: a control unit that controls a capacitance of the first capacitive element and the second capacitive element.
A power supply unit;
Capacitor element body composed of a dielectric layer and at least one pair of capacitor element electrodes that sandwich the dielectric layer and generate a desired electric field in the dielectric layer, and generated in the dielectric layer of the capacitor element body A variable impedance configured to include a resonant capacitor including a capacitive element that includes a stress control unit configured to control a stress to increase and increase a capacitance of the capacitive element body;
And an electronic device including a control unit that controls the capacitance of the capacitive element.
A first capacitive element body comprising a first dielectric layer and at least one pair of first capacitive element electrodes that sandwich the first dielectric layer and generate a desired electric field in the first dielectric layer; A first capacitor configured to include a first stress control unit configured to control a stress generated in the first dielectric layer of the first capacitor element body and to increase a capacitance of the first capacitor element body; A transmission device including a transmission-side antenna unit having a first resonance capacitor including an element and a first resonance coil connected to the first resonance capacitor;
A second capacitive element body comprising a second dielectric layer and at least one pair of second capacitive element electrodes that sandwich the second dielectric layer and generate a desired electric field in the second dielectric layer; A second capacitor configured to include a second stress control unit configured to control a stress generated in the second dielectric layer of the second capacitor element body and increase a capacitance of the second capacitor element body. A receiving device including a receiving-side antenna unit having a second resonance capacitor including an element and a second resonance coil connected to the second resonance capacitor;
A third capacitive element body comprising a third dielectric layer and at least one pair of third capacitive element electrodes that sandwich the third dielectric layer and generate a desired electric field in the third dielectric layer; A third capacitor configured to include a third stress control unit that controls a stress generated in the third dielectric layer of the third capacitor element body and increases a capacitance of the third capacitor element body; A power supply apparatus including a power supply side antenna unit having a third resonance capacitor including an element and a third resonance coil connected to the third resonance capacitor;
A fourth capacitive element body comprising a fourth dielectric layer and at least one pair of fourth capacitive element electrodes that sandwich the fourth dielectric layer and generate a desired electric field in the fourth dielectric layer; A fourth capacitor configured to include a fourth stress control unit that controls a stress generated in the fourth dielectric layer of the fourth capacitor element body and increases a capacitance of the fourth capacitor element body; A power receiving device including a power receiving side antenna unit having a fourth resonant capacitor including an element and a fourth resonant coil connected to the fourth resonant capacitor;
An electronic device comprising: a control unit that controls the capacitance of each of the first capacitive element, the second capacitive element, the third capacitive element, and the fourth capacitive element.
A first capacitive element body comprising a first dielectric layer and at least one pair of first capacitive element electrodes that sandwich the first dielectric layer and generate a desired electric field in the first dielectric layer; A first capacitor configured to include a first stress control unit configured to control a stress generated in the first dielectric layer of the first capacitor element body and to increase a capacitance of the first capacitor element body; A transmission device including a transmission-side antenna unit having a first resonance capacitor including an element and a first resonance coil connected to the first resonance capacitor;
A second capacitive element body comprising a second dielectric layer and at least one pair of second capacitive element electrodes that sandwich the second dielectric layer and generate a desired electric field in the second dielectric layer; A second capacitor configured to include a second stress control unit configured to control a stress generated in the second dielectric layer of the second capacitor element body and increase a capacitance of the second capacitor element body. A receiving device including a receiving-side antenna unit having a second resonance capacitor including an element and a second resonance coil connected to the second resonance capacitor;
A power supply section, a third dielectric layer, and at least one pair of third capacitive element electrodes sandwiching the third dielectric layer and generating a desired electric field in the third dielectric layer A third capacitive element main body, and a third stress control unit that controls a stress generated in the third dielectric layer of the third capacitive element main body and increases a capacitance of the third capacitive element main body. A power supply device including a variable impedance configured to include a third resonant capacitor including a configured third capacitive element, and each capacitance of the first capacitive element, the second capacitive element, and the third capacitive element An electronic device including a control unit for controlling.
A first capacitive element body comprising a first dielectric layer and at least one pair of first capacitive element electrodes that sandwich the first dielectric layer and generate a desired electric field in the first dielectric layer; A first capacitor configured to include a first stress control unit configured to control a stress generated in the first dielectric layer of the first capacitor element body and to increase a capacitance of the first capacitor element body; A power feeding device including a power feeding side antenna unit having a first resonant capacitor including an element and a first resonant coil connected to the first resonant capacitor;
A second capacitive element body comprising a second dielectric layer and at least one pair of second capacitive element electrodes that sandwich the second dielectric layer and generate a desired electric field in the second dielectric layer; A second capacitor configured to include a second stress control unit configured to control a stress generated in the second dielectric layer of the second capacitor element body and increase a capacitance of the second capacitor element body. A power receiving device including a power receiving side antenna unit having a second resonant capacitor including an element and a second resonant coil connected to the second resonant capacitor;
A power supply section, a third dielectric layer, and at least one pair of third capacitive element electrodes sandwiching the third dielectric layer and generating a desired electric field in the third dielectric layer A third capacitive element main body, and a third stress control unit that controls a stress generated in the third dielectric layer of the third capacitive element main body and increases a capacitance of the third capacitive element main body. A power supply device including a variable impedance configured to include a third resonance capacitor including a third capacitance element configured;
An electronic device comprising: a control unit that controls a capacitance of each of the first capacitive element, the second capacitive element, and the third capacitive element.
A first capacitive element body comprising a first dielectric layer and at least one pair of first capacitive element electrodes that sandwich the first dielectric layer and generate a desired electric field in the first dielectric layer; A first capacitor configured to include a first stress control unit configured to control a stress generated in the first dielectric layer of the first capacitor element body and to increase a capacitance of the first capacitor element body; A transmission device including a transmission-side antenna unit having a first resonance capacitor including an element and a first resonance coil connected to the first resonance capacitor;
A second capacitive element body comprising a second dielectric layer and at least one pair of second capacitive element electrodes that sandwich the second dielectric layer and generate a desired electric field in the second dielectric layer; A second capacitor configured to include a second stress control unit configured to control a stress generated in the second dielectric layer of the second capacitor element body and increase a capacitance of the second capacitor element body. A receiving device including a receiving-side antenna unit having a second resonance capacitor including an element and a second resonance coil connected to the second resonance capacitor;
A third capacitive element body comprising a third dielectric layer and at least one pair of third capacitive element electrodes that sandwich the third dielectric layer and generate a desired electric field in the third dielectric layer; A third capacitor configured to include a third stress control unit that controls a stress generated in the third dielectric layer of the third capacitor element body and increases a capacitance of the third capacitor element body; A power supply apparatus including a power supply side antenna unit having a third resonance capacitor including an element and a third resonance coil connected to the third resonance capacitor;
A fourth capacitive element body comprising a fourth dielectric layer and at least one pair of fourth capacitive element electrodes that sandwich the fourth dielectric layer and generate a desired electric field in the fourth dielectric layer; A fourth capacitor configured to include a fourth stress control unit that controls a stress generated in the fourth dielectric layer of the fourth capacitor element body and increases a capacitance of the fourth capacitor element body; A power receiving device including a power receiving side antenna unit having a fourth resonant capacitor including an element and a fourth resonant coil connected to the fourth resonant capacitor;
The power supply unit includes a fifth dielectric layer, and at least one pair of fifth capacitive element electrodes that sandwich the fifth dielectric layer and generate a desired electric field in the fifth dielectric layer. A fifth capacitive element main body, and a fifth stress control unit that controls a stress generated in the fifth dielectric layer of the fifth capacitive element main body and increases a capacitance of the fifth capacitive element main body. A power supply device including a variable impedance configured to include a fifth resonant capacitor including a fifth capacitive element configured as follows:
An electronic device comprising: a control unit that controls the capacitance of each of the first capacitive element, the second capacitive element, the third capacitive element, the fourth capacitive element, and the fifth capacitive element.
Capacitor element body composed of a dielectric layer and at least one pair of capacitor element electrodes that sandwich the dielectric layer and generate a desired electric field in the dielectric layer, and generated in the dielectric layer of the capacitor element body A resonance capacitor including a capacitive element configured to have a stress control unit that controls stress to increase and increases a capacitance of the capacitive element body;
An electronic device comprising: a resonance coil connected to the resonance capacitor.