Cylindrical multilayer ceramic capacitor and combination thereof

Abstract

A multilayer ceramic capacitor and a combination thereof for mounting to an electronic component includes a ceramic body and a plurality of external electrodes. The ceramic body is used for forming at least two sub-capacitors, each sub-capacitor comprises an independent inner electrode group, and the inner electrode group comprises a plurality of inner electrodes which are alternately stacked; wherein the ceramic body is of a cylindrical structure; the plurality of outer electrodes are arranged on the surface of the ceramic body, the outer electrodes comprise first outer electrodes and second outer electrodes with different polarities, and the inner electrodes of the at least two sub-capacitors are respectively connected with the different first outer electrodes and / or second outer electrodes; and the first external electrode and the second external electrode are connected and matched with the electronic assembly in different modes, so that at least part of the sub-capacitors are used, and the multi-layer ceramic capacitor selectively forms various different capacitance values. The multi-layer ceramic capacitor can meet the requirements of various different capacitance values required by a circuit, and the use number of the multi-layer ceramic capacitor can be greatly reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of capacitors, and in particular, to a cylindrical multilayer ceramic capacitor and a combination thereof. Background Art

[0002] As a common electronic component, a multilayer ceramic capacitor (MLCC) is widely used in various electronic products and circuits, and has been widely used in fields such as consumer electronics, new energy, and communication equipment. With the continuous improvement of the performance requirements of electronic devices, higher requirements are put forward for the performance, volume, and versatility of multilayer ceramic capacitors.

[0003] In the prior art, a single multilayer ceramic capacitor usually can only provide a single capacitance value, and in the design process, multiple multilayer ceramic capacitors with different capacitance values are often required to meet the requirements of the circuit, or multiple multilayer ceramic capacitors are connected in series or parallel to form different capacitance values. This increases the number of multilayer ceramic capacitors, not only increasing the manufacturing cost and production time, but also occupying more space for electronic components. Especially in compact electronic components, traditional cuboid-shaped multilayer ceramic capacitors cannot be closely arranged, increasing the complexity of the design and limiting the flexibility and compactness of circuit design.

[0004] Therefore, the existing multilayer ceramic capacitors need to be improved. Summary of the Invention

[0005] The purpose of the present invention is to provide a cylindrical multilayer ceramic capacitor and a combination thereof, achieving the purpose of forming multiple capacitance values with one multilayer ceramic capacitor, which can greatly reduce the number of multilayer ceramic capacitors used, not only reducing the manufacturing cost and production time, but also reducing the space occupied by electronic components, being beneficial to the flexibility and compactness of electronic component design, and thus being beneficial to the development of miniaturization of electronic components.

[0006] The purpose of the present invention is achieved by adopting the following technical solutions:

[0007] The present invention provides a cylindrical multilayer ceramic capacitor for installation to an electronic component, including:

[0008] A ceramic body for forming at least two sub-capacitors, each of the sub-capacitors including an independent inner electrode group and a plurality of dielectric layers, the inner electrode group including a plurality of inner electrodes stacked alternately, and each of the dielectric layers being located between adjacent inner electrodes; wherein, the ceramic body is arranged in a cylindrical structure;

[0009] A plurality of external electrodes are disposed on the surface of the ceramic body. The external electrodes include a first external electrode and a second external electrode with different polarities. The internal electrodes of the sub-capacitors are alternately connected to the first external electrode and the second external electrode, and the internal electrodes of at least two of the sub-capacitors are respectively connected to different ones of the first external electrode and / or the second external electrode. The first external electrode and the second external electrode are connected to the electronic component through different connection and cooperation methods so that at least some of the sub-capacitors are used and the multi-layer ceramic capacitor selectively forms a variety of different capacitance values.

[0010] As a further improvement of an embodiment of the present invention, at least one sub-capacitor is energized and independently electrically connected to the electronic component, or at least two sub-capacitors are energized and electrically connected to the electronic component in series and / or parallel.

[0011] As a further improvement of an embodiment of the present invention, the capacitance values of at least two of the sub-capacitors are set differently, or the capacitance value of each of the sub-capacitors is set differently;

[0012] And / or, the spacing between the internal electrodes of at least two of the sub-capacitors and / or the number of stacked dielectric layers are different.

[0013] As a further improvement of an embodiment of the present invention, at least two of the sub-capacitors have a common first external electrode or a common second external electrode, so that at least two of the sub-capacitors have the same input terminal or output terminal;

[0014] When at least two of the sub-capacitors have a common first external electrode, one end of a part of the internal electrodes of at least two of the sub-capacitors is exposed from the surface of the ceramic body and connected to the common first external electrode, and the other end of the other part of the internal electrodes of at least two of the sub-capacitors is exposed from the surface of the ceramic body and connected to different second external electrodes;

[0015] Or, when at least two of the sub-capacitors have a common second external electrode, one end of a part of the internal electrodes of at least two of the sub-capacitors is exposed from the surface of the ceramic body and connected to different first external electrodes, and the other end of the other part of the internal electrodes of at least two of the sub-capacitors is exposed from the surface of the ceramic body and connected to the common second external electrode.

[0016] As a further improvement of an embodiment of the present invention, a through hole penetrating the ceramic body in the direction of the internal electrode lamination is provided in the central region of the ceramic body. The surface of the ceramic body includes an inner surface forming the through hole, an outer surface opposite to the inner surface, and upper and lower surfaces respectively connecting the inner surface and the outer surface;

[0017] The first external electrode is disposed on the outer surface and extends to the upper surface and / or the lower surface of the ceramic body. The second external electrode is disposed on the inner surface and extends to the upper surface and / or the lower surface of the ceramic body. A plurality of the first external electrodes are spaced apart and disposed around the outer surface and / or a plurality of the second external electrodes are spaced apart and disposed around the inner surface.

[0018] As a further improvement of an embodiment of the present invention, a plurality of the sub-capacitors are stacked along the stacking direction of the inner electrodes, and the inner electrode of each sub-capacitor has an annular sheet structure with a central hollow.

[0019] A first spacer layer is provided between the ceramic bodies corresponding to adjacent sub-capacitors.

[0020] As a further improvement of an embodiment of the present invention, a plurality of the sub-capacitors are arranged side by side along the circumferential direction of the ceramic body, and the inner electrodes of each sub-capacitor located on the same dielectric layer have a fan-shaped sheet structure.

[0021] A second spacer layer is provided between the ceramic bodies corresponding to adjacent sub-capacitors.

[0022] As a further improvement of an embodiment of the present invention, the surface areas of the inner electrodes of each sub-capacitor located on the same dielectric layer are different.

[0023] As a further improvement of an embodiment of the present invention, the external electrode includes a bottom electrode disposed on the ceramic body and corresponding to and connected to the inner electrode, and an external electrode disposed on the bottom electrode and on a side away from the inner electrode. The bottom electrode is provided as a conductive ceramic layer, and the external electrode is provided as a metal layer.

[0024] The inner electrode is provided as a conductive ceramic layer.

[0025] The conductive ceramic layer includes a matrix material and an additive. The matrix material includes one or more of tin oxide, zirconium oxide, yttrium oxide, silicon carbide, and silicon nitride, and the additive includes one or more of barium titanate, calcium carbonate, and rare earths.

[0026] As a further improvement of an embodiment of the present invention, a plurality of first outer electrodes are provided. The ceramic body further includes a plurality of first protrusions located on the outer side surface. The first protrusions are disposed between two adjacent first outer electrodes and connect the two adjacent first outer electrodes. The side surface of the first protrusion facing away from the outer side surface is flush with the side surface of the first outer electrode facing away from the outer side surface; and / or, a plurality of second outer electrodes are provided. The ceramic body further includes a plurality of second protrusions located on the inner side surface. The second protrusions are disposed between two adjacent second outer electrodes and connect the two adjacent second outer electrodes. The side surface of the second protrusion facing away from the inner side surface is flush with the side surface of the second outer electrode facing away from the inner side surface;

[0027] The ceramic body further includes a first recess formed at the intersections of the upper surface and the lower surface with the outer side surface respectively. The first outer electrode is disposed on the outer side surface and extends to the first recess. The upper surface and the lower surface of the first outer electrode are respectively flush with the upper surface and the lower surface of the ceramic body;

[0028] The ceramic body further includes a second recess formed at the intersections of the upper surface and the lower surface with the inner side surface respectively. The second outer electrode is disposed on the inner side surface and extends to the second recess. The upper surface and the lower surface of the second outer electrode are respectively flush with the upper surface and the lower surface of the ceramic body.

[0029] The present invention also provides a multi-layer ceramic capacitor combination, including an electronic component and the multi-layer ceramic capacitor. The electronic component has a plurality of pads corresponding to the plurality of outer electrodes of the multi-layer ceramic capacitor, and the plurality of outer electrodes are respectively connected to the plurality of pads in one-to-one correspondence.

[0030] Compared with the prior art, the beneficial effects of the present invention at least include: by providing a plurality of sub-capacitors, the inner electrodes of at least two sub-capacitors are respectively connected to different first outer electrodes and / or second outer electrodes, and the first outer electrode and the second outer electrode are connected to the electronic component in different connection manners to selectively enable one of the sub-capacitors or a plurality of sub-capacitors, so that the multi-layer ceramic capacitor can selectively form a variety of different capacitance values. In this way, one multi-layer ceramic capacitor can meet the requirements of a variety of different capacitance values required by the circuit, which can greatly reduce the number of multi-layer ceramic capacitors used. It can not only reduce the manufacturing cost and production time to improve production efficiency, but also reduce the space occupied by the electronic component. Moreover, the cylindrical multi-layer ceramic capacitor can be closely arranged, which is further beneficial to the flexibility and compactness of the electronic component design, thus facilitating the development of miniaturization of the electronic component. Description of the Drawings

[0031] Figure 1It is a schematic three-dimensional structure diagram of a cylindrical multi-layer ceramic capacitor combination in Embodiment 1 of the present invention;

[0032] Figure 2 It is an exploded structure schematic diagram of a cylindrical multi-layer ceramic capacitor combination in Embodiment 1 of the present invention;

[0033] Figure 3 It is a schematic three-dimensional structure diagram of a ceramic body in Embodiment 1 of the present invention;

[0034] Figure 4 It is a schematic planar structure diagram of a cylindrical multi-layer ceramic capacitor in Embodiment 1 of the present invention;

[0035] Figure 5 It corresponds to Figure 4 A schematic diagram of the structural connection relationship between the inner electrode and the outer electrode on the same dielectric layer;

[0036] Figure 6 It is along Figure 4 A cross-sectional schematic diagram along line A-A in;

[0037] Figure 7 It is along Figure 4 A cross-sectional schematic diagram along line B-B in;

[0038] Figure 8 It is along Figure 4 A cross-sectional schematic diagram along line C-C in;

[0039] Figure 9 It is a schematic three-dimensional structure diagram of a cylindrical multi-layer ceramic capacitor combination in Embodiment 2 of the present invention;

[0040] Figure 10 It is an exploded structure schematic diagram of a cylindrical multi-layer ceramic capacitor combination in Embodiment 2 of the present invention;

[0041] Figure 11 It is a schematic three-dimensional structure diagram of a ceramic body in Embodiment 2 of the present invention;

[0042] Figure 12 It is a schematic planar structure diagram of a cylindrical multi-layer ceramic capacitor in Embodiment 2 of the present invention;

[0043] Figure 13 It corresponds to Figure 12 A schematic diagram of the structural connection between the inner electrode, the outer electrode and the second spacer layer on the same dielectric layer;

[0044] Figure 14 It is along Figure 12 A cross-sectional schematic diagram along line A-A in;

[0045] Figure 15 It is alongFigure 12 Schematic cross-sectional view along line B-B;

[0046] Figure 16 along Figure 12 Schematic cross-sectional view along line C-C;

[0047] Figure 17 Schematic perspective view of a cylindrical multi-layer ceramic capacitor combination in Embodiment 3 of the present invention.

[0048] Figure 18 Schematic cross-sectional view of a cylindrical multi-layer ceramic capacitor combination in Embodiment 3 of the present invention.

[0049] In the figure: 100, cylindrical multi-layer ceramic capacitor; 1, ceramic body; 11, dielectric layer; 12, internal electrode; 121a, 121b, first internal electrode; 122a, 122b, second internal electrode; 123a, 123b, third internal electrode; 124, lead-out part; 13, inner surface; 14, outer surface; 15, upper surface; 16, lower surface; 17, first protrusion; 18, first depression; 19, second depression; 2, external electrode; 21, 211a, 211b, 212a, 212b, 213a, 213b, first external electrode; 22, second external electrode; 3, sub-capacitor; 31a, 31b, first sub-capacitor; 32a, 32b, second sub-capacitor; 33a, 33b, third sub-capacitor; 4, through-hole; 51, first spacer layer; 52, second spacer layer; 200, electronic component; 210, pad. Detailed implementation manners

[0050] Example embodiments will now be described more fully with reference to the accompanying drawings. However, the example embodiments can be implemented in various forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this invention will be more complete and comprehensive, and the concept of the example embodiments will be fully conveyed to those skilled in the art. Like reference numerals in the figures denote the same or similar structures, and thus their repeated description will be omitted.

[0051] In the present invention, the words expressing position and direction are described by taking the accompanying drawings as examples, but can be changed according to needs, and all changes made are included in the protection scope of the present invention.

[0052] Refer to Figures 1 - 18As shown, the present invention provides a cylindrical multi-layer ceramic capacitor 100 for mounting to an electronic component 200. The cylindrical multi-layer ceramic capacitor 100 includes a cylindrical ceramic body 1 and a plurality of external electrodes 2. The plurality of external electrodes 2 can be disposed on the surface of the ceramic body 1, and the cylindrical multi-layer ceramic capacitor 100 can be electrically connected to the electronic component 200 through the external electrodes 2. The electronic component 200 can be a printed circuit board (PCB), a ceramic board provided with circuits, a housing provided with circuits, etc. When the electronic component 200 is a housing provided with circuits, the circuits in the housing can be metal terminals, and the metal terminals have pads 210 connected to the multi-layer ceramic capacitor 100. The cylindrical multi-layer ceramic capacitor 100 can be directly connected to the pads 210 of the metal terminals. Since the cylindrical multi-layer ceramic capacitor 100 adopts a cylindrical ceramic body 1, compared with the traditional rectangular multi-layer ceramic capacitor, it can avoid the stress concentration problem at the corners of the rectangular body, can evenly disperse stress, and is less likely to crack or be damaged in a vibration or impact environment, and is more suitable for applications in automotive electronics and industrial equipment with higher reliability requirements; moreover, the cylindrical multi-layer ceramic capacitor 100 has a larger surface area than the rectangular body under the same volume, which is conducive to heat dissipation and is suitable for high-power or high-temperature environments. In addition, in some compact designs, the cylindrical multi-layer ceramic capacitors 100 can be closely arranged, such as a honeycomb layout, to improve space utilization.

[0053] Specifically, referring to Figures 6 - 8 、 Figures 14 - 16 , the ceramic body 1 can include a plurality of stacked dielectric layers 11 and alternately stacked internal electrodes 12. The dielectric layers 11 are located between the internal electrodes 12, that is, the dielectric layers 11 are located between adjacent internal electrodes 12. The dielectric layers 11 can isolate the adjacent internal electrodes 12 to achieve electrical separation, thereby forming a capacitor.

[0054] The inner electrode 12 is provided as a conductive ceramic layer, specifically a laminate structure formed by using a conductive ceramic material. The inner electrode 12 can be disposed on the dielectric layer 11 by means of magnetron sputtering, printing, inkjet, 3D printing, tape casting, etc. The dielectric layer 11 is a ceramic material. Among them, the conductive ceramic can specifically be formed by using one or more of tin oxide, zirconium oxide, yttrium oxide, silicon carbide, and silicon nitride as matrix materials, and doping some additives in the matrix materials. The additives are used to improve the performance of the conductive ceramic so that the inner electrode 12 made of the conductive ceramic can match the sintering temperature and other properties of the dielectric layer 11. The type and dosage of the additives can be selected according to the type of properties to be improved and the degree of improvement required. The additives can be one or more of materials such as barium titanate, calcium carbonate, and rare earths. For example, barium titanate can be added as an additive in the matrix material to improve the sintering temperature and shrinkage expansion rate of the conductive ceramic. In addition, rare earths and their modified materials can also be added, etc. The conductive ceramic with improved performance can match the sintering temperature and shrinkage expansion rate of the dielectric layer 11. The inner electrode 12 made of the conductive ceramic has a stronger bonding force with the dielectric layer 11, which can not only reduce internal stress, improve moisture resistance, but also has better antioxidant performance.

[0055] Refer to Figures 1 - 4 、 Figures 9 - 12 , the ceramic body 1 is provided as a cylindrical structure, specifically an annular cylindrical structure. The central region of the ceramic body 1 has a through hole 4 penetrating the ceramic body 1 along the lamination direction of the inner electrode 12. The surface of the ceramic body 1 includes an inner surface 13 forming the through hole 4, an outer surface 14 opposite to the inner surface 13, and an upper surface 15 and a lower surface 16 respectively connecting the inner surface 13 and the outer surface 14. The outer surface 14 is the outer circumferential surface of the ceramic body 1.

[0056] As a preferred method, the upper surface 15 or the lower surface 16 of the ceramic body 1 is used as the mounting surface, that is, when the cylindrical multilayer ceramic capacitor 100 is mounted on the electronic component 200, the mounting surface is the side facing the electronic component 200. In the present invention, the lower surface 16 of the ceramic body 1 is used as the mounting surface as an example for description.

[0057] Refer to Figures 6 - 8 、 Figures 14 - 16 , the ceramic body 1 is used to form at least two sub-capacitors 3. Each sub-capacitor 3 corresponding to the ceramic body 1 is integrally formed, that is, a cylindrical multilayer ceramic capacitor 100 can include two or more sub-capacitors 3, and each sub-capacitor 3 includes an independent inner electrode group and a plurality of dielectric layers 11. The inner electrode group of each sub-capacitor 3 includes a plurality of inner electrodes 12 stacked alternately, and each dielectric layer 11 is located between adjacent inner electrodes 12.

[0058] Specifically, the external electrode 2 includes a first external electrode 21 and a second external electrode 22 with different polarities. The internal electrodes 12 of each sub-capacitor 3 are alternately connected to the first external electrode 21 and the second external electrode 22, and the internal electrodes 12 of at least two sub-capacitors 3 are respectively connected to different first external electrodes 21 and / or second external electrodes 22. That is, the internal electrodes 12 of at least two sub-capacitors 3 can be connected to different first external electrodes 21, can also be connected to different second external electrodes 22, or can be simultaneously connected to different first external electrodes 21 and different second external electrodes 22. The first external electrode 21 and the second external electrode 22 are connected to the electronic component 200 through different connection and cooperation methods so that at least some sub-capacitors 3 are used and the cylindrical multi-layer ceramic capacitor 100 selectively forms a variety of different capacitance values. For example, through circuit regulation on the electronic component 200 or through circuit regulation where the electronic component 200 is located, at least one sub-capacitor 3 can be powered on and independently electrically connected to the electronic component 200. That is to say, multiple sub-capacitors 3 can all be powered on and independently electrically connected to the electronic component 200. A cylindrical multi-layer ceramic capacitor 100 can be used as multiple capacitors, and the multiple sub-capacitors 3 are independent of each other. Or, through circuit regulation on or where the electronic component 200 is located, at least two sub-capacitors 3 can also be powered on and electrically connected to the electronic component 200 in series and / or parallel manners. That is, multiple sub-capacitors 3 are used in combination with each other, so as to achieve a variety of different capacitance values, and further meet the requirements of a variety of different capacitance values required by the circuit, thereby achieving the purpose of forming a variety of capacitance values with one cylindrical multi-layer ceramic capacitor 100. Therefore, through different connection and cooperation methods between the first external electrode 21 and the second external electrode 22 and the electronic component 200, one of the sub-capacitors 3 or multiple sub-capacitors 3 can be selectively activated. When multiple sub-capacitors 3 are activated, the multiple sub-capacitors 3 can be independently used as one capacitor each, or can be used in series and / or parallel manners.

[0059] In one embodiment, the capacitance values of at least two sub-capacitors 3 are set differently. That is to say, when the number of sub-capacitors 3 is two, the capacitance values of the two sub-capacitors 3 are different; when the number of sub-capacitors 3 is three or more, the capacitance values of at least two sub-capacitors 3 are set differently, that is, the capacitance values of some sub-capacitors 3 can be the same.

[0060] In another embodiment, the capacitance value of each sub-capacitor 3 is set differently.

[0061] In other embodiments, the capacitance values of each sub-capacitor 3 can also be set to be the same. By energizing some of the sub-capacitors 3 and electrically connecting them in series to the electronic component 200, and energizing some of the sub-capacitors 3 and electrically connecting them in parallel to the electronic component 200, various different capacitance values can be achieved. For example, when the number of sub-capacitors 3 is five, two sub-capacitors 3 can be connected in series to the electronic component 200, two sub-capacitors 3 can be connected in parallel to the electronic component 200, and another sub-capacitor 3 is electrically connected to the electronic component 200 alone. In this way, a multi-layer ceramic capacitor 100 can form three different capacitance values.

[0062] Of course, in the present application, the capacitance value of the sub-capacitor 3 can also be changed by changing the spacing between the inner electrodes 12 of the sub-capacitor 3 or the overlapping area of the inner electrodes 12, or by changing the number of stacked dielectric layers 11 of the sub-capacitor 3, or by changing the material of the dielectric layer 11. That is to say, the spacing between the inner electrodes 12 of the sub-capacitor 3, the overlapping area of the inner electrodes 12, the number of stacked dielectric layers 11, and the material of the dielectric layer 11 all affect the capacitance value of the sub-capacitor 3. Of course, the capacitance value of the sub-capacitor 3 can also be changed by other means, which will not be listed one by one here.

[0063] See Figure 1 、 Figures 6 - 9 、 Figures 14 - 16 , the first external electrode 21 is disposed on the outer surface 14 of the ceramic body 1 and extends to the upper surface 15 and / or the lower surface 16 of the ceramic body 1, the second external electrode 22 is disposed on the inner surface 13 of the ceramic body 1 and extends to the upper surface 15 and / or the lower surface 16 of the ceramic body 1, one end of the inner electrode 12 of the sub-capacitor 3 is exposed from the outer surface 14 of the ceramic body 1 and is electrically connected to the first external electrode 21, and the other end of the inner electrode 12 of the sub-capacitor 3 is exposed from the inner surface 13 of the ceramic body 1 and is electrically connected to the second external electrode 22.

[0064] In one embodiment, at least two sub-capacitors 3 share a common second external electrode 22, so that at least two sub-capacitors 3 have the same input terminal or output terminal. One end of a part of the inner electrodes 12 of at least two sub-capacitors 3 is exposed from the surface of the ceramic body 1 and is connected to different first external electrodes 21, and the other end of the other part of the inner electrodes 12 of at least two sub-capacitors 3 is exposed from the surface of the ceramic body 1 and is connected to the common second external electrode 22.

[0065] That is to say, see Figure 1 and Figure 9, in this embodiment, the cylindrical ceramic capacitor 100 specifically includes a shared second external electrode 22 and a plurality of independently provided first external electrodes 21. The plurality of first external electrodes 21 are disposed on the outer surface 14 of the ceramic body 1 and extend to the upper surface 15 and the lower surface 16 of the ceramic body 1, and the plurality of first external electrodes 21 are spaced apart and circumferentially arranged on the outer surface 14. The second external electrode 22 is laid on the inner surface 13 of the ceramic body 1 and extends to the upper surface 15 and the lower surface 16 of the ceramic body 1. Refer to Figures 6 - 8 , Figures 14 - 16 , one end of the inner electrode 12 of at least two sub-capacitors 3 is exposed from the outer surface 14 of the ceramic body 1 and connected to different first external electrodes 21, and the other end of the inner electrode 12 of at least two sub-capacitors 3 is exposed from the inner surface 13 of the ceramic body 1 and connected to the shared second external electrode 22. In this way, each sub-capacitor 3 can be electrically connected to the electronic component 200 through different first external electrodes 21. By means of circuit regulation, the sub-capacitor 3 corresponding to the first external electrode 32 connected to the electronic component 200 is used, while the sub-capacitor 3 corresponding to the first external electrode 32 not connected to the electronic component 200 is not used. Therefore, one of the sub-capacitors 3 can be selectively used, or two or more of the sub-capacitors 3 can be independently used, or two or more of the sub-capacitors 3 can be selected simultaneously for series or parallel use to meet the requirements of various different capacitance values required by the circuit, so as to achieve the purpose of forming multiple capacitance values with one cylindrical multilayer ceramic capacitor 100.

[0066] Of course, in this embodiment, refer to Figure 17 and Figure 18When there are multiple first external electrodes 21, the ceramic body 1 may further include a plurality of first protrusions 17 located on the outer surface 14 of the ceramic body 1. The first protrusions 17 are disposed between two adjacent first external electrodes 21 and connect the two adjacent first external electrodes 21. The side surface of the first protrusion 17 facing away from the outer surface 14 is flush with the side surface of the first external electrode 21 facing away from the outer surface 14. The ceramic body 1 may further include a plurality of first recesses 18 formed at the intersections of the upper surface 15 and the lower surface 16 of the ceramic body 1 with the outer surface 14 respectively. The number of the first recesses 18 is the same as the number of the first external electrodes 21, and the first recesses 18 correspond to the first external electrodes 21 one by one. The first external electrodes 21 are disposed on the outer surface 14 and extend to the corresponding first recesses 18. The upper surface and the lower surface of the first external electrode 21 are respectively flush with the upper surface 15 and the lower surface 16 of the ceramic body 1. The ceramic body 1 further includes second recesses 19 formed at the intersections of the upper surface 15 and the lower surface 16 of the ceramic body 1 with the inner surface 13 respectively. The second recesses 19 are specifically ring structures with hollow centers. The shared second external electrode 22 is disposed on the inner surface 13 and extends to the second recesses 19. The upper surface and the lower surface of the second external electrode 22 are respectively flush with the upper surface 15 and the lower surface 16 of the ceramic body 1. In this way, the first external electrodes 21 do not protrude from the outer surface 14, the upper surface 15 and the lower surface 16 of the ceramic body 1, and the second external electrode 22 does not protrude from the upper surface 15 and the lower surface 16 of the ceramic body 1, forming a regular cylindrical multilayer ceramic capacitor 100 as a whole. When the cylindrical multilayer ceramic capacitor 100 is directly or indirectly subjected to an external force, a large pressure will not be generated on a small contact area, so that the first external electrodes 21 and the second external electrodes 22 are not easily loosened or detached, and the ability to resist deformation is stronger.

[0067] In another embodiment, at least two sub-capacitors 3 have a common first external electrode 21, such that at least two sub-capacitors 3 have the same input or output terminal. One end of a part of the internal electrodes 12 of at least two sub-capacitors 3 exposes from the surface of the ceramic body 1 and is connected to the common first external electrode 21, and the other end of the other part of the internal electrodes 12 of at least two sub-capacitors 3 exposes from the surface of the ceramic body 1 and is connected to different second external electrodes 22. That is to say, in this embodiment, the cylindrical multi-layer ceramic capacitor 100 specifically includes a common first external electrode 21 and a plurality of independently provided second external electrodes 22. The first external electrode 21 is laid on the outer surface 14 of the ceramic body 1 and extends to the upper surface 15 and the lower surface 16 of the ceramic body 1. The plurality of second external electrodes 22 are provided on the inner surface 13 of the ceramic body 1 and extend to the upper surface 15 and the lower surface 16 of the ceramic body 1, and the plurality of second external electrodes 22 are arranged at intervals in the circumferential direction on the inner surface 13. One end of a part of the internal electrodes 12 of at least two sub-capacitors 3 exposes from the outer surface 14 of the ceramic body 1 and is connected to the common first external electrode 21, and the other end of the other part of the internal electrodes 12 of at least two sub-capacitors 3 exposes from the inner surface 13 of the ceramic body 1 and is connected to different second external electrodes 22.

[0068] Of course, in this embodiment, when there are multiple second outer electrodes 22, the ceramic body 1 may further include a plurality of second convex portions (not shown in the figure) located on the inner side surface 13 of the ceramic body 1. The second convex portion is disposed between two adjacent second outer electrodes 22 and connects the two adjacent second outer electrodes 22. The side surface of the second convex portion facing away from the inner side surface 14 is flush with the side surface of the second outer electrode 22 facing away from the inner side surface 13. The ceramic body 1 may further include a first concave portion 18 formed at the junctions of the upper surface 15 and the lower surface 16 of the ceramic body 1 with the outer side surface 14 respectively. The first concave portion 18 is specifically a circular ring structure with a hollow center. The shared first outer electrode 21 is disposed on the outer side surface 14 and extends to the first concave portion 18. The upper surface and the lower surface of the first outer electrode 21 are respectively flush with the upper surface 15 and the lower surface 16 of the ceramic body 1. The ceramic body 1 further includes a plurality of second concave portions 19 formed at the junctions of the upper surface 15 and the lower surface 16 of the ceramic body 1 with the inner side surface 13 respectively. The number of the second concave portions 19 is the same as the number of the second outer electrodes 22, and the second concave portions 19 correspond to the second outer electrodes 22 one by one. The second outer electrodes 22 are disposed on the inner side surface 13 and extend to the second concave portions 19. The upper surface and the lower surface of the second outer electrodes 22 are respectively flush with the upper surface 15 and the lower surface 16 of the ceramic body 1. In this way, the first outer electrode 21 does not protrude from the upper surface 15 and the lower surface 16 of the ceramic body 1, and the second outer electrode 22 does not protrude from the inner side surface 13, the upper surface 15 and the lower surface 16 of the ceramic body 1, thus forming a regular cylindrical multi-layer ceramic capacitor 100 as a whole. When the cylindrical multi-layer ceramic capacitor 100 is directly or indirectly affected by an external force, a large pressure will not be generated on a small contact area. Moreover, the second convex portion 17 connects two adjacent second outer electrodes 22, playing a role in supporting and connecting the two adjacent second outer electrodes 22, making the second outer electrodes 22 not easy to loosen or fall off, and strengthening the structural stability.

[0069] In other embodiments, the cylindrical multi-layer ceramic capacitor 100 specifically includes a plurality of independently provided first outer electrodes 21 and a plurality of independently provided second outer electrodes 22. The plurality of first outer electrodes 21 are disposed on the outer side surface 14 of the ceramic body 1 and are spaced apart and circumferentially arranged. The plurality of second outer electrodes 22 are disposed on the inner side surface of the ceramic body 1 and are spaced apart and circumferentially arranged. The first outer electrodes 21 and the second outer electrodes 22 are arranged in one-to-one correspondence. At least two sub-capacitors 3 are respectively connected to different first outer electrodes 21 and second outer electrodes 22. That is to say, one end of a part of the inner electrodes 12 of at least two sub-capacitors 3 is exposed from the outer side surface 14 of the ceramic body 1 and is connected to different first outer electrodes 21, and the other end of the other part of the inner electrodes 12 of at least two sub-capacitors 3 is exposed from the inner side surface 13 of the ceramic body 1 and is connected to the second outer electrode 22 corresponding to the first outer electrode 21.

[0070] Of course, in this embodiment, since a plurality of first outer electrodes 21 and a plurality of second outer electrodes 22 are provided, the ceramic body 1 may further include a plurality of first protrusions 17 located on the outer surface 14 and a plurality of second protrusions located on the inner surface 13. The first protrusions 17 are disposed between two adjacent first outer electrodes 21 and connect the two first outer electrodes 21. The second protrusions are disposed between two adjacent second outer electrodes 22 and connect the two second outer electrodes 22. The ceramic body 1 may further include first recesses 18 formed at the intersections of its upper surface 15 and lower surface 16 with the outer surface 14 respectively. The number of the first recesses 18 is the same as that of the first outer electrodes 21, and the first recesses 18 correspond to the first outer electrodes 21 one by one. The first outer electrodes 21 are disposed on the outer surface 14 and extend into the first recesses 18. The upper surface and the lower surface of the first outer electrodes 21 are flush with the upper surface 15 and the lower surface 16 of the ceramic body 1 respectively. The ceramic body 1 further includes second recesses 19 formed at the intersections of its upper surface 15 and lower surface 16 with the inner surface 13 respectively. The number of the second recesses 19 is the same as that of the second outer electrodes 22, and the second recesses 19 correspond to the second outer electrodes 22 one by one. The second outer electrodes 22 are disposed on the inner surface 13 and extend into the second recesses 19. The upper surface and the lower surface of the second outer electrodes 22 are flush with the upper surface 15 and the lower surface 16 of the ceramic body 1 respectively.

[0071] Specifically, in the present invention, the outer electrode 2 includes a bottom layer electrode disposed on the ceramic body 1 and correspondingly connected to the inner electrode 12, and an external electrode disposed on the bottom layer electrode and on the side away from the inner electrode 12. The bottom layer electrode is provided as a conductive ceramic layer, and the external electrode is provided as a metal layer. The metal layer may be provided as two layers of metal, such as a copper layer and a tin layer or a nickel layer and a tin layer. The metal layer may also be provided as three layers of metal, such as a copper layer, a nickel layer, and a tin layer, etc. The metal close to the bottom layer electrode is disposed on the bottom layer electrode by adhesion or chemical plating. Refer to Figure 1 and Figure 9 , each first outer electrode 21 includes a first bottom layer electrode disposed on the ceramic body 1 and connected to the inner electrode 12, and a first external electrode disposed on the side of the first bottom layer electrode away from the inner electrode 12. The shared second outer electrode 22 includes a second bottom layer electrode disposed on the ceramic body 1 and connected to the inner electrode 12, and a second external electrode disposed on the side of the second bottom layer electrode away from the inner electrode 12. The first bottom layer electrode and the second bottom layer electrode are both conductive ceramic layers.

[0072] The conductive ceramic layer includes a matrix material and additives. The matrix material includes one or more of tin oxide, zirconium oxide, yttrium oxide, silicon carbide, and silicon nitride, and the additives include one or more of barium titanate, calcium carbonate, and rare earths. Since the bottom electrode of the outer electrode 2 and the main material of the dielectric layer 11 in the ceramic body 1 are both ceramic materials, the bottom electrode of the outer electrode 2 and the dielectric layer 11 can have a strong bonding force after sintering, thereby effectively increasing the bonding force between the outer electrode 2 and the ceramic body 1; moreover, the bottom electrode of the outer electrode 2 and the ceramic body 1, which are both of ceramic material, can more easily form an integral body, thereby making the sealing between the outer electrode 2 and the ceramic body 1 better, effectively isolating the entry of external water vapor into the joint between the outer electrode 2 and the dielectric layer 11, and improving the waterproof performance of the multilayer ceramic capacitor.

[0073] Example 1

[0074] See Figures 1 - 8 , this embodiment provides a cylindrical multilayer ceramic capacitor 100 for mounting to an electronic component 200. The cylindrical multilayer ceramic capacitor 100 includes a ceramic body 1 and a plurality of outer electrodes 2. The cylindrical multilayer ceramic capacitor 100 can be electrically connected to the electronic component 200 through the outer electrodes 2, and the outer electrodes 2 and the electronic component 200 can be connected and matched in different ways so that the cylindrical multilayer ceramic capacitor 100 can selectively form a variety of different capacitance values.

[0075] The ceramic body 1 is arranged in an annular cylindrical structure. The central region of the ceramic body 1 has a through hole 4 that penetrates the ceramic body 1 along the stacking direction of the inner electrodes 12. The surface of the ceramic body 1 includes an inner surface 13 forming the through hole 4, an outer surface 14 opposite to the inner surface 13, and upper and lower surfaces 15 and 16 connecting the inner surface 13 and the outer surface 14 respectively.

[0076] The ceramic body 1 includes a plurality of stacked dielectric layers 11 and alternately stacked inner electrodes 12. The dielectric layers 11 are located between the inner electrodes 12. The ceramic body 1 is used to form at least two sub-capacitors 3. Each sub-capacitor 3 corresponding to the ceramic body 1 is integrally formed, and each sub-capacitor 3 includes an independent inner electrode group.

[0077] See Figures 6 - 8 , a plurality of sub-capacitors 3 are stacked along the stacking direction of the inner electrodes 12. The spacing between the inner electrodes 12 and / or the number of stacked dielectric layers 11 of each sub-capacitor 3 are different, so that the capacitance values of each sub-capacitor 3 can be different.

[0078] See also Figure 5 , the inner electrode 12 of each sub-capacitor 3 is in a ring-shaped sheet structure with a central hollow.

[0079] A plurality of external electrodes 2 are provided on the surface of the ceramic body 1 and are electrically connected to the corresponding internal electrodes 12 respectively. The external electrodes 2 include a first external electrode 21 and a second external electrode 22 with different polarities. The first external electrode 21 is provided on the outer side surface 14 of the ceramic body 1 and extends to the upper surface 15 and the lower surface 16 of the ceramic body 1. The second external electrode 22 is provided on the inner side surface 13 of the ceramic body 1 and extends to the upper surface 15 and the lower surface 16 of the ceramic body 1.

[0080] See Figure 1 and Figure 4 In this embodiment, a plurality of sub-capacitors 3 share the second external electrode 22. That is, in this embodiment, a plurality of independent first external electrodes 21 and a shared second external electrode 22 are provided. The plurality of independent first external electrodes 21 are arranged at intervals around the circumferential direction of the ceramic body 1 on the outer side surface 14 of the ceramic body 1 and extend to the upper surface 15 and the lower surface 16 of the ceramic body 1. The shared second external electrode 22 is laid on the inner side surface 13 of the ceramic body 1 and extends to the upper surface 15 and the lower surface 16 of the ceramic body 1. One end of a part of the internal electrodes 12 of the plurality of sub-capacitors 3 is exposed from the through holes 4 of the ceramic body 1 and is all connected to the second external electrode 22.

[0081] The number of the first external electrodes 21 is set to be the same as the number of the sub-capacitors 3. One end of a part of the internal electrodes 12 of the plurality of sub-capacitors 3 is exposed from the inner side surface 13 of the ceramic body 1 and is electrically connected to the shared second external electrode 22. The other end of the other part of the internal electrodes 12 of the plurality of sub-capacitors 3 is exposed from the outer side surface 14 of the ceramic body 1 and is electrically connected to different first external electrodes 21. That is, in each sub-capacitor 3, the internal electrode 12 is connected to the corresponding first external electrode 21 and is separated from the remaining first external electrodes 21. Refer to Figure 5 In each sub-capacitor 3, a lead-out portion 124 is further provided at one end of the internal electrode 12 exposed from the outer side surface 14 of the ceramic body 1. The lead-out portion 124 is used to connect the internal electrode 12 to the corresponding first external electrode 21, while Figure 5 the internal electrode 12 of the sub-capacitor 3 shown is separated from the remaining first external electrodes 21. Thus, the internal electrode 12 of each sub-capacitor 3 is electrically connected to a different first external electrode 21. By selecting different first external electrodes 21 to cooperate with the second external electrode 22, different sub-capacitors 3 can be activated to be electrically connected to the electronic component 200, so that each sub-capacitor 3 can be used independently. By means of circuit regulation, one of the sub-capacitors 3 can be selected for use, or two or more sub-capacitors 3 can be selected for series or parallel use, achieving the purpose of forming multiple capacitance values with one cylindrical multi-layer ceramic capacitor 100.

[0082] More specifically, refer to Figures 6 - 8, a first spacer layer 51 is provided between the ceramic bodies 1 corresponding to the adjacent sub-capacitors 3. The cross-section of the first spacer layer 51 in the direction perpendicular to the stacking direction of the internal electrodes 12 is in an annular structure. The thickness of the first spacer layer 51 can be greater than the thickness of the dielectric layer 11 corresponding to the adjacent sub-capacitors 3. The first spacer layer 51 separates the adjacent sub-capacitors 3 from each other, avoiding mutual influence between the adjacent sub-capacitors 3, so that the adjacent sub-capacitors 3 are independent of each other. The number of the first spacer layers 51 can be multiple, and the multiple first spacer layers 51 can enable the cylindrical multi-layer ceramic capacitor 100 to form more sub-capacitors 3.

[0083] The first spacer layer 51 can be sintered simultaneously with a part of the ceramic body 1 corresponding to the sub-capacitor 3, that is, the first spacer layer 51 and the dielectric layer 11 and the internal electrode 12 of the sub-capacitor 3 are preferably sintered integrally. The first spacer layer 51 and the ceramic body 1 parts corresponding to each sub-capacitor 3 together form a complete ceramic body 1. Compared with the dielectric layer 11 of the sub-capacitor 3, no internal electrode 12 is provided on the first spacer layer 51. The first spacer layer 51 and the dielectric layer 11 of the sub-capacitor 3 can be formed of the same material, and the first spacer layer 51 and the dielectric layer 11 of the sub-capacitor 2 can also be formed of different materials.

[0084] Exemplarily, referring to Figures 3 - 8 , the ceramic body 1 includes a first sub-capacitor 31a, a second sub-capacitor 32a, and a third sub-capacitor 33a that are sequentially stacked along the stacking direction of the internal electrodes 12. A first spacer layer 51 is provided between the first sub-capacitor 31a and the second sub-capacitor 32a, and between the second sub-capacitor 32a and the third sub-capacitor 33a. The internal electrodes 12 of the first sub-capacitor 31a, the second sub-capacitor 32a, and the third sub-capacitor 33a are all in the shape of circular ring flakes, and the distances between the internal electrodes 12 and / or the number of stacked dielectric layers 11 of the first sub-capacitor 31a, the second sub-capacitor 32a, and the third sub-capacitor 33a are different, so that the capacitance values of the first sub-capacitor 31a, the second sub-capacitor 32a, and the third sub-capacitor 33a can be different. Correspondingly, three independent first external electrodes 21 are spaced apart on the outer surface 14 of the ceramic body 1, and a common second external electrode 22 is provided on the inner surface 13 of the ceramic body 1. Referring to Figure 5 and Figure 6 , one end of a part of the first internal electrode 121a of the first sub-capacitor 31a is provided with a lead-out portion 124. The lead-out portion 124 exposes from the outer surface 14 of the ceramic body 1 and is electrically connected to the first external electrode 211a, and the other end of the other part of the first internal electrode 121a exposes from the inner surface 13 of the ceramic body 1 and is electrically connected to the common second external electrode 22. That is to say, the first internal electrode 121a in the first sub-capacitor 31a is only connected to the first external electrode 211a and is separated from the first external electrode 212a and the first external electrode 213a; referring to Figure 7, one end of a part of the second inner electrode 122a of the second sub-capacitor 32a is provided with a lead-out portion 124. The lead-out portion 124 exposes from the outer surface 14 of the ceramic body 1 and is electrically connected to the first outer electrode 212a. The other end of the other part of the second inner electrode 122a exposes from the inner surface 13 of the ceramic body 1 and is electrically connected to the common second outer electrode 22. That is to say, the second inner electrode 122a in the second sub-capacitor 32a is only connected to the first outer electrode 212a and is separated from the first outer electrode 211a and the first outer electrode 213a; see Figure 8 , one end of a part of the third inner electrode 123a of the third sub-capacitor 33a is provided with a lead-out portion 124. The lead-out portion 124 exposes from the outer surface 14 of the ceramic body 1 and is electrically connected to the first outer electrode 213a. The other end of the other part of the third inner electrode 123a exposes from the inner surface 13 of the ceramic body 1 and is electrically connected to the common second outer electrode 22. That is to say, the third inner electrode 123a in the third sub-capacitor 33a is only connected to the first outer electrode 213a and is separated from the first outer electrode 211a and the first outer electrode 212a. Thus, the first sub-capacitor 31a, the second sub-capacitor 32a and the third sub-capacitor 33a can be respectively and electrically connected to the electronic component 200 through the cooperation of the first outer electrode 211a, the first outer electrode 212a and the first outer electrode 213a with the second outer electrode 22. By means of circuit regulation, one of the sub-capacitors 3 can be selectively used, or two or more of the sub-capacitors 3 can be independently used, or two or more of the sub-capacitors 3 can be simultaneously selected for series or parallel use to meet the requirements of various different capacitance values needed by the circuit, so as to achieve the purpose of forming multiple capacitance values with one cylindrical multi-layer ceramic capacitor 100.

[0085] Embodiment 2

[0086] See Figures 9 - 16 , different from Embodiment 1, in this embodiment, multiple sub-capacitors 3 are arranged side by side along the circumferential direction of the ceramic body 1, and the inner electrodes 12 of each sub-capacitor 3 located on the same dielectric layer 11 are in a fan-shaped sheet structure, as Figure 13 shown.

[0087] Specifically, see Figure 11 and Figure 13 , a second spacer layer 52 is provided between the ceramic bodies 1 corresponding to adjacent sub-capacitors 3. The second spacer layer 52 separates the inner electrodes 12 in adjacent sub-capacitors 3 to avoid mutual influence between adjacent sub-capacitors 3, so that adjacent sub-capacitors 3 are independent of each other. The number of the second spacer layers 52 can be multiple, and the multiple second spacer layers 52 can enable the cylindrical multi-layer ceramic capacitor 100 to form more sub-capacitors 3. Each second spacer layer 52 can be arranged in a laminated structure corresponding to the dielectric layer 11 and the inner electrode 12 in the stacking direction of the dielectric layer 11, or can be arranged in an integrally formed block structure.

[0088] The second spacer layer 52 can be formed by sintering simultaneously with the ceramic body 1 portion corresponding to the sub-capacitor 3. That is, the second spacer layer 52 and the dielectric layers 11 and inner electrodes 12 of each sub-capacitor 3 are preferably sintered integrally. The second spacer layer 52 and the ceramic body 1 portion corresponding to each sub-capacitor 3 together form a complete ceramic body 1. Compared with the dielectric layer 11 of the sub-capacitor 3, no inner electrode 12 is provided on the second spacer layer 52. The second spacer layer 52 and the dielectric layer 11 of the sub-capacitor 3 can be formed of the same material, or the second spacer layer 52 and the dielectric layer 11 of the sub-capacitor 2 can also be formed of different materials.

[0089] More specifically, the surface areas of the inner electrodes 12 of each sub-capacitor 3 located on the same dielectric layer 11 are different to achieve different capacitance values for each sub-capacitor 3. For example, the inner electrode 12 is in a fan-shaped structure, and the angles of the fan-shaped corners formed by the inner electrodes 12 in different sub-capacitors 3 can be the same or different.

[0090] See Figure 9 and Figure 12 In this embodiment, multiple sub-capacitors 3 have a shared second external electrode 22. That is, in this embodiment, multiple independent first external electrodes 21 and a shared second external electrode 22 are provided. The multiple independent first external electrodes 21 are spaced around and disposed on the outer surface 14 of the ceramic body 1 and extend to the upper surface 15 and lower surface 16 of the ceramic body. The shared second external electrode 22 is laid on the inner surface 13 of the ceramic body 1 and extends to the upper surface 15 and lower surface 16 of the ceramic body 1. The number of the first external electrodes 21 is set the same as the number of the sub-capacitors 3. One end of a part of the inner electrodes 12 of the multiple sub-capacitors 3 exposes from the outer surface 14 of the ceramic body 1 and is electrically connected to different first external electrodes 21, and the other end of the other part of the inner electrodes 12 of the multiple sub-capacitors 3 exposes from the inner surface 13 of the ceramic body 1 and is electrically connected to the shared second external electrode 22.

[0091] Exemplarily, see Figures 11 - 16, the ceramic body 1 includes a first sub-capacitor 31b, a second sub-capacitor 32b, and a third sub-capacitor 33b arranged side by side along the circumferential direction of the ceramic body 1. A second spacer layer 52 is provided between the first sub-capacitor 31b and the second sub-capacitor 32b, and between the second sub-capacitor 32b and the third sub-capacitor 33b. The inner electrodes 12 of the first sub-capacitor 31b, the second sub-capacitor 32b, and the third sub-capacitor 33b located on the same dielectric layer 11 are all in a fan-shaped sheet structure, and the surface areas of the inner electrodes 12 of the first sub-capacitor 31b, the second sub-capacitor 32b, and the third sub-capacitor 33b located on the same dielectric layer 11 are different, so that different capacitance values of the first sub-capacitor 31b, the second sub-capacitor 32b, and the third sub-capacitor 33b can be achieved. Correspondingly, three independent first outer electrodes 21 are arranged at intervals on the outer surface 14 of the ceramic body 1, and a common second outer electrode 22 is provided on the inner surface 13 of the ceramic body 1. For a clearer understanding of this embodiment, in Figures 14 to 16 only the first outer electrode 21 of one sub-capacitor 3 is shown respectively. Refer to Figure 13 and Figure 14 , one end of a part of the first inner electrode 121b of the first sub-capacitor 31b exposes from the outer surface 14 of the ceramic body 1 and is electrically connected to the first outer electrode 211b, and the other end of the other part of the first inner electrode 121b exposes from the inner surface 13 of the ceramic body 1 and is electrically connected to the common second outer electrode 22; refer to Figure 13 and Figure 15 , one end of a part of the second inner electrode 122b of the second sub-capacitor 32b exposes from the outer surface 14 of the ceramic body 1 and is electrically connected to the first outer electrode 212b, and the other end of the other part of the second inner electrode 122b exposes from the inner surface 13 of the ceramic body 1 and is electrically connected to the common second outer electrode 22; refer to Figure 13 and Figure 16 , one end of a part of the third inner electrode 123b of the third sub-capacitor 33b exposes from the outer surface 14 of the ceramic body 1 and is electrically connected to the first outer electrode 213b, and the other end of the other part of the third inner electrode 123b exposes from the inner surface 13 of the ceramic body 1 and is electrically connected to the common second outer electrode 22. In this way, the first sub-capacitor 31b, the second sub-capacitor 32b, and the third sub-capacitor 33b can be electrically connected to the electronic component 200 through the cooperation of the first outer electrode 211b, the first outer electrode 212b, and the first outer electrode 213b and the second outer electrode 22. By means of circuit regulation, one of the sub-capacitors 3 can be selected for use, or two or more of the sub-capacitors 3 can be independently used, or two or more of the sub-capacitors 3 can be selected simultaneously for series or parallel use to meet the requirements of various different capacitance values required by the circuit, and the purpose of forming multiple capacitance values with one multilayer ceramic capacitor 100 is achieved.

[0092] Embodiment 3

[0093] See Figure 17 and Figure 18 In this embodiment, multiple sub-capacitors 3 are arranged side by side along the circumferential direction of the ceramic body 1. The inner electrodes 12 of each sub-capacitor 3 located on the same dielectric layer 11 are in a fan-shaped sheet structure. However, different from Embodiment 2, the ceramic body 1 further includes a plurality of first protrusions 17 located on the outer surface 14 of the ceramic body 1. The first protrusions 17 are arranged between two adjacent first outer electrodes 21 and connect the two adjacent first outer electrodes 21. Moreover, the side surface of the first protrusion 17 facing away from the outer surface 14 is flush with the side surface of the first outer electrode 21 facing away from the outer surface 14. The setting of the first protrusions 17 can not only make the outer circumferential surface of the cylindrical multi-layer ceramic capacitor 100 flat, but also play a role in supporting and connecting two adjacent first outer electrodes 21, strengthening the structural stability. And the first protrusions 17 are arranged at intervals between the corresponding first outer electrodes 21 of the ceramic body 1, playing an insulating and isolating function, and can also prevent foreign objects from entering the cylindrical multi-layer ceramic capacitor 100 and causing electrical connection between adjacent first outer electrodes 21, thereby ensuring the mutual independence between adjacent sub-capacitors 3.

[0094] Specifically, the number of the first protrusions 17 is the same as the number of the second spacer layers 52. The first protrusions 17 and the second spacer layers 52 correspond to each other one by one, and each first protrusion 17 is connected to the corresponding second spacer layer 52 and integrally formed with the second spacer layer 52. That is to say, the first protrusions 17, the second spacer layers 52 can be integrally sintered with the ceramic body 1 corresponding to the sub-capacitor 3. The first protrusions 17, the second spacer layers 52 and the dielectric layer 11 of the sub-capacitor 3 can be formed of the same material or different materials.

[0095] See Figure 18, the ceramic body 1 further includes first recessed portions 18 formed at the intersections of its upper surface 15 and lower surface 16 with the outer side surface 14 respectively. The number of the first recessed portions 18 is set to be the same as the number of the first external electrodes 21, and the first recessed portions 18 and the first external electrodes 21 are in one-to-one correspondence. Each first external electrode 21 is disposed on the outer side surface 14 and extends to the corresponding first recessed portion 18. The upper surface and the lower surface of the first external electrode 21 are flush with the upper surface 15 and the lower surface 16 of the ceramic body 1 respectively; the ceramic body 1 further includes second recessed portions 19 formed at the intersections of its upper surface 15 and lower surface 16 with the inner side surface 14 respectively. The second recessed portions 19 are specifically annular structures with a hollow center. The second external electrodes 22 are disposed on the inner side surface 13 and extend to the second recessed portions 19. The upper surface and the lower surface of the second external electrodes 22 are flush with the upper surface 15 and the lower surface 16 of the ceramic body 1 respectively. Thus, a regular cylindrical multi-layer ceramic capacitor 100 is formed, and the external electrodes 2 do not protrude from the ceramic body 1. When the cylindrical multi-layer ceramic capacitor 100 is directly or indirectly subjected to an external force, a large pressure will not be generated on a small contact area, so that the external electrodes 2 are not easily loosened or detached, and the ability to resist deformation is stronger; moreover, the first protruding portions 17 directly provided on the ceramic body 1 are spaced between the corresponding first external electrodes 21 of the ceramic body 1, which plays an insulating and isolating function, and can also prevent foreign objects from entering the multi-layer ceramic capacitor 100 and causing the adjacent first external electrodes 21 to be electrically connected, thereby ensuring that the adjacent sub-capacitors 3 are independent of each other.

[0096] Of course, in this embodiment, the structural designs of the first protruding portions 17, the first recessed portions 18 and the second recessed portions 19 can also be combined and applied to the structure in Embodiment 1. The sub-capacitors 3 are stacked along the stacking direction of the inner electrodes 12. The structures of the first protruding portions 17, the first recessed portions 18 and the second recessed portions 19 are correspondingly added on the ceramic body 1. The specific positions of each structure and the specific connection relationships between the structures are the same as those in this embodiment, and will not be elaborated here too much.

[0097] The present invention also provides a cylindrical multi-layer ceramic capacitor combination, including an electronic component 200 and a cylindrical multi-layer ceramic capacitor 100. The electronic component 200 has a plurality of pads 210 corresponding to the plurality of external electrodes 2 of the cylindrical multi-layer ceramic capacitor 100. The plurality of external electrodes 2 are connected to the plurality of pads 210 in one-to-one correspondence. One or more of the sub-capacitors 3 are selected for use by means of circuit regulation, that is, one or more of the sub-capacitors 3 are selected to be energized by means of circuit regulation to enable the capacitance values of the one or more sub-capacitors 3, or two or more of the sub-capacitors 3 are selected to be energized and used in series or in parallel by means of circuit regulation, so as to form different capacitance values.

[0098] In summary, the present invention provides a cylindrical multi-layer ceramic capacitor with multiple sub-capacitors. The inner electrodes of at least two sub-capacitors are respectively connected to different first outer electrodes and / or second outer electrodes. The first outer electrodes and the second outer electrodes are connected to the electronic components in different ways to selectively enable one or more of the sub-capacitors, thereby enabling the cylindrical multi-layer ceramic capacitor to selectively form multiple different capacitance values. In this way, a single multi-layer ceramic capacitor can meet the requirements of multiple different capacitance values needed by the circuit, significantly reducing the number of multi-layer ceramic capacitors used. This not only reduces manufacturing costs and production time to improve production efficiency, but also reduces the space occupied by the electronic components. Moreover, the use of cylindrical multi-layer ceramic capacitors allows for close arrangement, further facilitating the flexibility and compactness of the electronic component design, thus promoting the development of miniaturization of electronic components.

[0099] Although the embodiments of the present invention have been shown and described above, it should be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Without departing from the principles and spirit of the present invention, those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the invention. All such changes should fall within the protection scope of the claims of the present invention.

Claims

1. A cylindrical multi-layer ceramic capacitor for mounting to an electronic component, characterized in that, Comprising: A ceramic body for forming at least two sub-capacitors, each sub-capacitor including an independent inner electrode group and a plurality of dielectric layers, the inner electrode group including a plurality of inner electrodes stacked alternately, and each dielectric layer being located between adjacent inner electrodes; wherein, the ceramic body is arranged in a cylindrical structure; A plurality of outer electrodes arranged on the surface of the ceramic body, the outer electrodes including a first outer electrode and a second outer electrode with different polarities, the inner electrodes of the sub-capacitors being alternately connected to the first outer electrode and the second outer electrode, and the inner electrodes of at least two sub-capacitors being respectively connected to different first outer electrodes and / or second outer electrodes, the first outer electrode and the second outer electrode being connected to the electronic component through different connection and cooperation methods so that at least some sub-capacitors are used and a multi-layer ceramic capacitor selectively forms a variety of different capacitance values.

2. The cylindrical multilayer ceramic capacitor according to claim 1, wherein At least one sub-capacitor is energized and independently electrically connected to the electronic component, or at least two sub-capacitors are energized and electrically connected to the electronic component in series and / or parallel.

3. The cylindrical multilayer ceramic capacitor according to claim 1, characterized in that, The capacitance values of at least two of the sub-capacitors are set differently, or the capacitance value of each sub-capacitor is set differently; And / or, the spacing between the inner electrodes and / or the number of stacked dielectric layers of at least two of the sub-capacitors are different.

4. The cylindrical multilayer ceramic capacitor according to claim 1, wherein, At least two of the sub-capacitors have a common first outer electrode or second outer electrode, so that at least two of the sub-capacitors have the same input terminal or output terminal; When at least two of the sub-capacitors have a common first outer electrode, one end of a part of the inner electrodes of at least two of the sub-capacitors exposes from the surface of the ceramic body and is connected to the common first outer electrode, and the other end of another part of the inner electrodes of at least two of the sub-capacitors exposes from the surface of the ceramic body and is connected to different second outer electrodes; Or, when at least two of the sub-capacitors have a common second outer electrode, one end of a part of the inner electrodes of at least two of the sub-capacitors exposes from the surface of the ceramic body and is connected to different first outer electrodes, and the other end of another part of the inner electrodes of at least two of the sub-capacitors exposes from the surface of the ceramic body and is connected to the common second outer electrode.

5. The cylindrical multi-layer ceramic capacitor according to claim 1, characterized in that, A through hole penetrating the ceramic body along the stacking direction of the inner electrodes is provided in the central region of the ceramic body, and the surface of the ceramic body includes an inner surface forming the through hole, an outer surface opposite to the inner surface, and an upper surface and a lower surface respectively connecting the inner surface and the outer surface; The first outer electrode is arranged on the outer surface and extends to the upper surface and / or the lower surface of the ceramic body, the second outer electrode is arranged on the inner surface and extends to the upper surface and / or the lower surface of the ceramic body, and a plurality of the first outer electrodes are arranged at intervals around the outer surface and / or a plurality of the second outer electrodes are arranged at intervals around the inner surface.

6. The cylindrical multi-layer ceramic capacitor according to claim 5, characterized in that, A plurality of the sub-capacitors are stacked along the stacking direction of the inner electrodes, and the inner electrodes of each sub-capacitor are in a ring-shaped sheet structure with a hollow center; And a first spacer layer is provided between the corresponding ceramic bodies of adjacent sub-capacitors.

7. The cylindrical multilayer ceramic capacitor according to claim 5, characterized in that, A plurality of sub-capacitors are arranged in parallel along the circumferential direction of the ceramic body, and the inner electrode of each sub-capacitor located on the same dielectric layer is in a fan-shaped sheet structure; A second spacing layer is arranged between the ceramic bodies corresponding to adjacent sub-capacitors.

8. The cylindrical multi-layer ceramic capacitor according to claim 7, wherein, The surface areas of the inner electrodes of each of the sub-capacitors located on the same dielectric layer are different.

9. The cylindrical multilayer ceramic capacitor according to claim 1, characterized in that, The external electrode comprises a bottom electrode disposed on the ceramic body and correspondingly connected to the internal electrode and an external electrode disposed on the bottom electrode and away from the internal electrode, wherein the bottom electrode is configured as a conductive ceramic layer and the external electrode is configured as a metal layer; The inner electrode is provided as a conductive ceramic layer; The conductive ceramic layer includes a matrix material and an additive, wherein the matrix material includes one or more of tin oxide, zirconium oxide, yttrium oxide, silicon carbide, and silicon nitride, and the additive includes one or more of barium titanate, calcium carbonate, and rare earth.

10. The cylindrical multilayer ceramic capacitor according to claim 5, characterized in that, There are a plurality of first external electrodes, and the ceramic body further includes a plurality of first protrusions located on the outer surface, the first protrusions are arranged between two adjacent first external electrodes and connect the two adjacent first external electrodes, and the side of the first protrusion facing away from the outer surface is flush with the side of the first external electrode facing away from the outer surface; and / or, there are a plurality of second external electrodes, and the ceramic body further includes a plurality of second protrusions located on the inner surface, the second protrusions are arranged between two adjacent second external electrodes and connect the two adjacent second external electrodes, and the side of the second protrusion facing away from the inner surface is flush with the side of the second external electrode facing away from the inner surface; The ceramic body further includes a first recessed portion formed at the intersection of the upper surface and the lower surface with the outer surface respectively, the first external electrode is arranged on the outer surface and extends to the first recessed portion, and the upper surface and the lower surface of the first external electrode are flush with the upper surface and the lower surface of the ceramic body respectively; The ceramic body also includes a second recessed portion formed at the intersection of the upper surface, the lower surface and the inner surface respectively, the second external electrode is arranged on the inner surface and extends to the second recessed portion, and the upper surface and the lower surface of the second external electrode are respectively flush with the upper surface and the lower surface of the ceramic body.

11. A multi-layer ceramic capacitor combination, characterized in that, It comprises an electronic component and a cylindrical multilayer ceramic capacitor as described in any one of claims 1 to 10, wherein the electronic component has a plurality of pads corresponding to a plurality of external electrodes of the cylindrical multilayer ceramic capacitor, and the plurality of external electrodes are connected to the plurality of pads one by one.

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