CN107768100A - A kind of preparation method of LTCC flat surface transformers - Google Patents
A kind of preparation method of LTCC flat surface transformers Download PDFInfo
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- CN107768100A CN107768100A CN201711173827.2A CN201711173827A CN107768100A CN 107768100 A CN107768100 A CN 107768100A CN 201711173827 A CN201711173827 A CN 201711173827A CN 107768100 A CN107768100 A CN 107768100A
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- ferrite
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- 238000002360 preparation method Methods 0.000 title claims abstract description 11
- 229910000859 α-Fe Inorganic materials 0.000 claims abstract description 32
- 238000000576 coating method Methods 0.000 claims abstract description 14
- 230000035699 permeability Effects 0.000 claims abstract description 13
- 239000011248 coating agent Substances 0.000 claims abstract description 10
- 239000000758 substrate Substances 0.000 claims abstract description 9
- 238000005245 sintering Methods 0.000 claims abstract description 4
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical group [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 4
- 238000013461 design Methods 0.000 abstract description 5
- 238000004804 winding Methods 0.000 description 8
- 239000000919 ceramic Substances 0.000 description 7
- 230000009466 transformation Effects 0.000 description 5
- 239000000463 material Substances 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 3
- 238000009413 insulation Methods 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 239000004020 conductor Substances 0.000 description 2
- 239000003989 dielectric material Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000012545 processing Methods 0.000 description 2
- UQSXHKLRYXJYBZ-UHFFFAOYSA-N Iron oxide Chemical compound [Fe]=O UQSXHKLRYXJYBZ-UHFFFAOYSA-N 0.000 description 1
- 230000015556 catabolic process Effects 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 238000006731 degradation reaction Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000004744 fabric Substances 0.000 description 1
- 239000011888 foil Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 230000009477 glass transition Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 230000000977 initiatory effect Effects 0.000 description 1
- 239000011810 insulating material Substances 0.000 description 1
- 239000000696 magnetic material Substances 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 238000004377 microelectronic Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 239000002002 slurry Substances 0.000 description 1
- 238000000844 transformation Methods 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F27/00—Details of transformers or inductances, in general
- H01F27/28—Coils; Windings; Conductive connections
- H01F27/2804—Printed windings
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F27/00—Details of transformers or inductances, in general
- H01F27/28—Coils; Windings; Conductive connections
- H01F27/30—Fastening or clamping coils, windings, or parts thereof together; Fastening or mounting coils or windings on core, casing, or other support
- H01F27/306—Fastening or mounting coils or windings on core, casing or other support
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F41/00—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties
- H01F41/02—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets
- H01F41/04—Apparatus or processes specially adapted for manufacturing or assembling magnets, inductances or transformers; Apparatus or processes specially adapted for manufacturing materials characterised by their magnetic properties for manufacturing cores, coils, or magnets for manufacturing coils
- H01F41/041—Printed circuit coils
- H01F41/046—Printed circuit coils structurally combined with ferromagnetic material
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F17/00—Fixed inductances of the signal type
- H01F17/0006—Printed inductances
- H01F2017/0066—Printed inductances with a magnetic layer
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F27/00—Details of transformers or inductances, in general
- H01F27/28—Coils; Windings; Conductive connections
- H01F27/2804—Printed windings
- H01F2027/2809—Printed windings on stacked layers
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F27/00—Details of transformers or inductances, in general
- H01F27/28—Coils; Windings; Conductive connections
- H01F27/2804—Printed windings
- H01F2027/2819—Planar transformers with printed windings, e.g. surrounded by two cores and to be mounted on printed circuit
Landscapes
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Coils Or Transformers For Communication (AREA)
Abstract
The present invention relates to a kind of preparation method of LTCC flat surface transformers, including：Low permeability dielectric layer is chosen, primary coil and secondary coil are respectively printed at described in same layer on low permeability dielectric layer, obtain coil dielectric layer；Internal diameter of the coil dielectric layer along coil and external diameter are cut, obtain coil layer；Ferrite substrate layer is chosen, cuts out ferrite sheet one, the ferrite sheet two to match with coil layer outside and interior shape；Ferrite sheet one and ferrite sheet two are embedded in coil layer outwardly and inwardly respectively, obtain mosaic coating；By multiple mosaic coatings together with the stacking of upper and lower ferrite end cap, LTCC flat surface transformers are formed by hot pressed sintering.The preparation method of LTCC flat surface transformers of the present invention has a higher coefficient of coup compared with conventional planar transformer, low leakage inductance, can meet the design requirement of high voltage planar transformer and high frequency planar transformer.
Description
Technical field
The present invention relates to flat surface transformer manufacture technology field, and in particular to a kind of making side of LTCC flat surface transformers
Method.
Background technology
In recent years, with the continuous development of microelectronics information technology, complete electronic set towards miniaturization, portability, it is multi-functional,
The directions such as digitlization are developed, and promote electronic component constantly to develop to miniaturization, integrated and high frequency direction.Winding transformation
Device is design most ripe at present, in view of volume, hand winding etc. limit：The efficiency of enamel-covered wire coiling processing is low, insulation
Performance is hardly resulted under the influence of coiling and is effectively ensured, it is necessary to carry out further insulation processing, such as wind insulating tape or
Use reinforced insulation line etc..This undoubtedly reduces actual magnetic material window utilization rate so that the volume of transformer can not be effective
Ground reduces.And enamel-covered wire coiling must use the skeleton of plastics or other insulating materials, the radiating of winding become one it is non-
The problem of often big.Therefore, winding transformer can not meet miniaturization, integrated, cost degradation application demand, and there is an urgent need to open
Send out novel planar transformer.
Planar high voltage transformer mainly has three kinds of PCB transformers, piezoelectric ceramic transformer and LTCC transformers.
For PCB types transformer using glass transition temperature than relatively low expoxy glass cloth material, working under high pressure will
Occur the phenomenon that mechanical performance declines such as deforming, the failure of transformer can be caused.Moreover, for the design of high tension transformer, become
Depressor turn ratio wants big and winding is more.However, because the making number of plies of multi-layer PCB has obvious limitation so that very more
The winding of circle is difficult to realize, and such transformer is difficult to be raised to high pressure.
The principle of piezoelectric ceramic transformer is the forward and inverse piezo-electric effect using piezoceramic material, and with its resonant frequency
Inspire voltage.The piezoelectric ceramic transformer majority used at present is monolithic shape or multilayer strip, the device system of this structure
It is simple to make technique, step-up ratio is higher, but load capacity is poor, and power is small, and power density is low, is generally used for high voltage, low current, height
Impedance load.
Comparatively speaking, the combination property of LTCC transformers and piezoelectric ceramic transformer occupies clear superiority, especially its
Small size and lightweight have remarkable effect for improving Exploding Foil initiation system anti high overload ability.LTCC advantages：Material system
System includes physics and chemically flexible dielectric slurry and conductor material, can be burnt altogether with ferrite ltcc substrate, produces with excellent
Different magnetic coupling, high magnetic permeability（Relative permeability>400）, high resistivity（> 1012Ω·cm）With good saturation degree（>
0.3T）.Burn altogether ferrite and dielectric material may be used as be attached or accommodate the part as power electronic system half
The substrate of conductor part and other discrete devices.
LTCC flat surface transformers and traditional core-type transformer communicate on boosting principle, and difference is LTCC
Metal paste, using multi-layer ferrite ceramics as dielectric material, is screen printed onto iron oxygen by flat surface transformer without the iron core of closure
Primary, secondary windings is formed on body ceramics, the wire coil on corresponding ceramics is connected to form primary and secondary by plated-through hole
Winding.LTCC flat surface transformers are much smaller than traditional core-type transformer in volume and quality, still, current LTCC plane transformations
The shortcomings of leakage inductance is big, and transformation efficiency is not high also be present in device.
The content of the invention
It is an object of the invention to provide a kind of preparation method of LTCC flat surface transformers, the transformation made by this method
Device, not only cost, leakage inductance, loss are relatively low, and small volume, voltage and reliability are higher.
To achieve the above object, present invention employs following technical scheme：
A kind of preparation method of LTCC flat surface transformers, comprises the following steps：
（1）Low permeability dielectric layer is chosen, low permeability dielectric layer is punched out and filled；
（2）Primary coil and secondary coil are respectively printed at described in same layer on low permeability dielectric layer, obtain coil medium
Layer；
（3）Internal diameter of the coil dielectric layer along coil and external diameter are cut, obtain coil layer；
（4）Ferrite substrate layer is chosen, a through hole being adapted with the shape of the coil layer is opened up on iron structure base board layer,
So that coil layer is embedded in the through hole, ferrite sheet one is obtained；
（5）Ferrite substrate layer is chosen, cuts out the ferrite sheet two being adapted with the interior shape of the coil layer；
（6）Ferrite sheet one and ferrite sheet two are embedded in coil layer outwardly and inwardly respectively, obtain mosaic coating；
（7）Multiple mosaic coatings are overlapped, and the mosaic coating after superposition is passed through together with the stacking of upper and lower ferrite end cap
Hot pressed sintering forms LTCC flat surface transformers.
In such scheme, the coil layer is annulus or straight-flanked ring.
In such scheme, step（3）In, it is described to be cut internal diameter of the coil dielectric layer along coil and external diameter, according to
0.01~1mm of external diameter more than exterior loop and 0.01~1mm of internal diameter less than interior loop size is cut.
As shown from the above technical solution, the preparation method of LTCC flat surface transformers of the present invention and conventional planar transformation
Device is compared, and is had the higher coefficient of coup, low leakage inductance, can be met the design of high voltage planar transformer and high frequency planar transformer
It is required that.
Brief description of the drawings
Fig. 1 is the Making programme schematic diagram of the mosaic coating of the present invention；
Fig. 2 is the section structural representation of the mosaic coating of the present invention；
Fig. 3 is structural representation of the mosaic coating of the present invention together with the stacking of upper and lower ferrite end cap.
Embodiment
The present invention will be further described below in conjunction with the accompanying drawings：
As shown in figure 1, the preparation method of the LTCC flat surface transformers of the present embodiment, comprises the following steps：
S1:Low permeability dielectric layer 2 is chosen, 21 and filling are punched out to low permeability dielectric layer 2；
S2:Primary coil 3 and secondary coil 4 are respectively printed on same layer low permeability dielectric layer 2, obtain coil medium
Layer；
S3:Internal diameter of the coil dielectric layer along coil and external diameter are cut, according to and internal diameter bigger 0.01~1mm than coil outer diameter
Small 0.01~1mm shape is cut, and is formed the ring of a circle or rectangle, is obtained coil layer 5；In the present embodiment, press
It is smaller 0.5mm than interior loop to be sheared according to bigger 0.5mm than coil outer diameter.
S4:Choose ferrite substrate layer 1, opened up on iron structure base board layer 1 one be adapted with the shape of coil layer 5 lead to
Hole, so that coil layer 5 is embedded in through hole, obtain ferrite sheet 1；
S5:Ferrite substrate layer 1 is chosen, cuts out the ferrite sheet 2 12 being adapted with the interior shape of coil layer 5；
S6:Ferrite sheet 1 and ferrite sheet 2 12 are embedded in coil layer 5 outwardly and inwardly respectively, obtain mosaic coating 8；
S7:Multiple mosaic coatings 8 are overlapped, and by the mosaic coating 8 after superposition and upper ferrite end cap 6 and lower ferrite end cap
7 stackings form LTCC flat surface transformers together, by hot pressed sintering.
Embodiment described above is only that the preferred embodiment of the present invention is described, not to the model of the present invention
Enclose and be defined, on the premise of design spirit of the present invention is not departed from, technical side of the those of ordinary skill in the art to the present invention
The various modifications and improvement that case is made, it all should fall into the protection domain of claims of the present invention determination.
Claims (3)
1. a kind of preparation method of LTCC flat surface transformers, it is characterised in that comprise the following steps：
（1）Low permeability dielectric layer is chosen, low permeability dielectric layer is punched out and filled；
（2）Primary coil and secondary coil are respectively printed at described in same layer on low permeability dielectric layer, obtain coil medium
Layer；
（3）Internal diameter of the coil dielectric layer along coil and external diameter are cut, obtain coil layer；
（4）Ferrite substrate layer is chosen, a through hole being adapted with the shape of the coil layer is opened up on iron structure base board layer,
So that coil layer is embedded in the through hole, ferrite sheet one is obtained；
（5）Ferrite substrate layer is chosen, cuts out the ferrite sheet two being adapted with the interior shape of the coil layer；
（6）Ferrite sheet one and ferrite sheet two are embedded in coil layer outwardly and inwardly respectively, obtain mosaic coating；
（7）Multiple mosaic coatings are overlapped, and the mosaic coating after superposition is passed through together with the stacking of upper and lower ferrite end cap
Hot pressed sintering forms LTCC flat surface transformers.
2. the preparation method of LTCC flat surface transformers according to claim 1, it is characterised in that：Step（3）In, the line
Ring layer is annulus or straight-flanked ring.
3. the preparation method of LTCC flat surface transformers according to claim 1, it is characterised in that：Step（3）In, it is described to incite somebody to action
Internal diameter and external diameter of the coil dielectric layer along coil are cut, according to 0.01~1mm of external diameter more than exterior loop and less than interior lines
0.01~1mm of internal diameter of circle size is cut.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711173827.2A CN107768100B (en) | 2017-11-22 | 2017-11-22 | A kind of production method of LTCC flat surface transformer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711173827.2A CN107768100B (en) | 2017-11-22 | 2017-11-22 | A kind of production method of LTCC flat surface transformer |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107768100A true CN107768100A (en) | 2018-03-06 |
| CN107768100B CN107768100B (en) | 2019-11-22 |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107768104A (en) * | 2017-12-09 | 2018-03-06 | 中国电子科技集团公司第四十三研究所 | A kind of preparation method of LTCC flat surface transformers |
| CN109524215A (en) * | 2018-12-29 | 2019-03-26 | 矽力杰半导体技术(杭州)有限公司 | Transformer and its manufacturing method is laminated |
| CN109545532A (en) * | 2018-11-23 | 2019-03-29 | 深圳顺络电子股份有限公司 | A kind of flat surface transformer and preparation method thereof based on LTCC |
| CN110911088A (en) * | 2019-11-29 | 2020-03-24 | 中国科学院电子学研究所 | LTCC high-voltage transformer |
| CN112530685A (en) * | 2020-11-27 | 2021-03-19 | 赣州和信诚电子有限公司 | Planar transformer with accurate winding head |
| CN114743787A (en) * | 2022-03-29 | 2022-07-12 | 中国电子科技集团公司第四十三研究所 | Manufacturing method of detachable LTCC planar transformer |
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| CN2509690Y (en) * | 2001-12-19 | 2002-09-04 | 李明宗 | Improvement of multi-layer chip inductance structure |
| CN1452774A (en) * | 1998-07-06 | 2003-10-29 | 密德康姆股份有限公司 | Multilayer transformer having electrical connection in magnetic core |
| CN101599347A (en) * | 2009-06-17 | 2009-12-09 | 北京科耐特科技有限公司 | Coil board and production method thereof and the method for producing multi-layer planar transformer |
| CN101789311A (en) * | 2010-02-11 | 2010-07-28 | 深圳顺络电子股份有限公司 | LTCC low temperature co-fired ceramic flat surface transformer |
| KR20120054432A (en) * | 2010-11-19 | 2012-05-30 | 삼성전기주식회사 | An inner electrode printing sheet for layered inductor and manufacturing method for layered inductor using thereof |
| CN104465020A (en) * | 2014-12-25 | 2015-03-25 | 深圳市固电电子有限公司 | Cascading inductor based on metal magnetic slurry and preparation method thereof |
| CN204857391U (en) * | 2015-07-28 | 2015-12-09 | 深圳市高斯博电子科技有限公司 | Adopt reactor of compound magnetic circuit structure |
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2017
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| CN1452774A (en) * | 1998-07-06 | 2003-10-29 | 密德康姆股份有限公司 | Multilayer transformer having electrical connection in magnetic core |
| CN2509690Y (en) * | 2001-12-19 | 2002-09-04 | 李明宗 | Improvement of multi-layer chip inductance structure |
| CN101599347A (en) * | 2009-06-17 | 2009-12-09 | 北京科耐特科技有限公司 | Coil board and production method thereof and the method for producing multi-layer planar transformer |
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| KR20120054432A (en) * | 2010-11-19 | 2012-05-30 | 삼성전기주식회사 | An inner electrode printing sheet for layered inductor and manufacturing method for layered inductor using thereof |
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Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107768104A (en) * | 2017-12-09 | 2018-03-06 | 中国电子科技集团公司第四十三研究所 | A kind of preparation method of LTCC flat surface transformers |
| CN109545532A (en) * | 2018-11-23 | 2019-03-29 | 深圳顺络电子股份有限公司 | A kind of flat surface transformer and preparation method thereof based on LTCC |
| CN109524215A (en) * | 2018-12-29 | 2019-03-26 | 矽力杰半导体技术(杭州)有限公司 | Transformer and its manufacturing method is laminated |
| CN110911088A (en) * | 2019-11-29 | 2020-03-24 | 中国科学院电子学研究所 | LTCC high-voltage transformer |
| CN112530685A (en) * | 2020-11-27 | 2021-03-19 | 赣州和信诚电子有限公司 | Planar transformer with accurate winding head |
| CN112530685B (en) * | 2020-11-27 | 2021-09-21 | 赣州和信诚电子有限公司 | Planar transformer with accurate winding head |
| CN114743787A (en) * | 2022-03-29 | 2022-07-12 | 中国电子科技集团公司第四十三研究所 | Manufacturing method of detachable LTCC planar transformer |
| CN114743787B (en) * | 2022-03-29 | 2023-11-21 | 中国电子科技集团公司第四十三研究所 | Manufacturing method of detachable LTCC planar transformer |
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| CN107768100B (en) | 2019-11-22 |
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