WO2005029517A1 - ビーズ型ノイズフィルタ - Google Patents
ビーズ型ノイズフィルタ Download PDFInfo
- Publication number
- WO2005029517A1 WO2005029517A1 PCT/JP2003/012044 JP0312044W WO2005029517A1 WO 2005029517 A1 WO2005029517 A1 WO 2005029517A1 JP 0312044 W JP0312044 W JP 0312044W WO 2005029517 A1 WO2005029517 A1 WO 2005029517A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- bead
- noise filter
- magnetic core
- type noise
- component
- Prior art date
Links
- 239000011324 bead Substances 0.000 title claims abstract description 27
- 229910000859 α-Fe Inorganic materials 0.000 claims abstract description 35
- 239000000696 magnetic material Substances 0.000 claims abstract description 10
- 239000000203 mixture Substances 0.000 claims description 11
- 230000005540 biological transmission Effects 0.000 abstract description 5
- 230000000052 comparative effect Effects 0.000 description 13
- 229910003962 NiZn Inorganic materials 0.000 description 12
- 239000011248 coating agent Substances 0.000 description 7
- 238000000576 coating method Methods 0.000 description 7
- 230000035699 permeability Effects 0.000 description 7
- 230000005855 radiation Effects 0.000 description 7
- 230000004907 flux Effects 0.000 description 6
- 238000004519 manufacturing process Methods 0.000 description 6
- 230000001629 suppression Effects 0.000 description 6
- 238000004804 winding Methods 0.000 description 6
- KOAWAWHSMVKCON-UHFFFAOYSA-N 6-[difluoro-(6-pyridin-4-yl-[1,2,4]triazolo[4,3-b]pyridazin-3-yl)methyl]quinoline Chemical compound C=1C=C2N=CC=CC2=CC=1C(F)(F)C(N1N=2)=NN=C1C=CC=2C1=CC=NC=C1 KOAWAWHSMVKCON-UHFFFAOYSA-N 0.000 description 5
- 238000005259 measurement Methods 0.000 description 5
- 229910017706 MgZn Inorganic materials 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 2
- 229910001035 Soft ferrite Inorganic materials 0.000 description 2
- FFBHFFJDDLITSX-UHFFFAOYSA-N benzyl N-[2-hydroxy-4-(3-oxomorpholin-4-yl)phenyl]carbamate Chemical compound OC1=C(NC(=O)OCC2=CC=CC=C2)C=CC(=C1)N1CCOCC1=O FFBHFFJDDLITSX-UHFFFAOYSA-N 0.000 description 2
- 230000000903 blocking effect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000009413 insulation Methods 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 239000011812 mixed powder Substances 0.000 description 2
- 239000000843 powder Substances 0.000 description 2
- 239000002994 raw material Substances 0.000 description 2
- 229920006395 saturated elastomer Polymers 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 229910018663 Mn O Inorganic materials 0.000 description 1
- 239000004372 Polyvinyl alcohol Substances 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000008901 benefit Effects 0.000 description 1
- 238000001354 calcination Methods 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000008187 granular material Substances 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 229920002451 polyvinyl alcohol Polymers 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000008054 signal transmission Effects 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F17/00—Fixed inductances of the signal type
- H01F17/04—Fixed inductances of the signal type with magnetic core
- H01F17/06—Fixed inductances of the signal type with magnetic core with core substantially closed in itself, e.g. toroid
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F1/00—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties
- H01F1/01—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials
- H01F1/03—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity
- H01F1/12—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials
- H01F1/34—Magnets or magnetic bodies characterised by the magnetic materials therefor; Selection of materials for their magnetic properties of inorganic materials characterised by their coercivity of soft-magnetic materials non-metallic substances, e.g. ferrites
- H01F1/342—Oxides
- H01F1/344—Ferrites, e.g. having a cubic spinel structure (X2+O)(Y23+O3), e.g. magnetite Fe3O4
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F17/00—Fixed inductances of the signal type
- H01F17/04—Fixed inductances of the signal type with magnetic core
- H01F17/06—Fixed inductances of the signal type with magnetic core with core substantially closed in itself, e.g. toroid
- H01F2017/065—Core mounted around conductor to absorb noise, e.g. EMI filter
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F17/00—Fixed inductances of the signal type
- H01F17/04—Fixed inductances of the signal type with magnetic core
- H01F17/06—Fixed inductances of the signal type with magnetic core with core substantially closed in itself, e.g. toroid
- H01F2017/067—Core with two or more holes to lead through conductor
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
- H01F3/00—Cores, Yokes, or armatures
- H01F3/08—Cores, Yokes, or armatures made from powder
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03H—IMPEDANCE NETWORKS, e.g. RESONANT CIRCUITS; RESONATORS
- H03H1/00—Constructional details of impedance networks whose electrical mode of operation is not specified or applicable to more than one type of network
- H03H2001/0092—Inductor filters, i.e. inductors whose parasitic capacitance is of relevance to consider it as filter
Definitions
- the present invention relates to a bead type noise filter used for a signal line (signal line) for mounting on a circuit board and a power supply line (such as a DC line) for suppressing unnecessary radiation noise and the like.
- signal lines signal lines and power lines
- the simplest method for suppressing such noise is to penetrate the signal line through a closed magnetic path core called a bead core having a toroidal shape or a tubular shape (hereinafter collectively referred to as a toroidal shape).
- the signal wire is often wound around the magnetic core once and penetrated (one turn), but a plurality of holes are provided in the magnetic core, and the signal line is wound multiple times around the magnetic core using this number of holes. Sometimes it comes.
- reference numeral 1 denotes a closed magnetic core (bead core) made of a soft magnetic material having a high specific resistance.
- the magnetic core 1 has a cylindrical outer shape, and is provided with one through hole 1a in the center axis direction, and the signal line 2 is passed through the through hole 1a to form a bead type noise filter.
- the number of the through holes la is not limited to one, but may be plural (see FIG. 2).
- the number 1 for suppressing unnecessary radiation noisyzu of 0 Number 1 0 0 MH z, such also available high resistivity N i Z n Fuwerai Bok at high frequencies (1 0 2-1 0 5 Q m) is used for core 1.
- a high specific resistance was required for the magnetic core 1 so that no problem would occur if the signal line 2 without insulation coating was directly in contact with the inner surface of the magnetic core 1 (through hole la). Therefore, NiZn ferrite is used for the core 1 from this point.
- the bead-type noise filter has a very simple structure, since the Ni Zn ferrite containing expensive Ni has been used as a raw material in the past, the bead-type noise filter can be used for expensive components. There was a problem of becoming.
- MgZn ferrite Another inexpensive soft ferrite is MgZn ferrite.
- MgZn ferrite is inferior in soft magnetic properties such as initial permeability and saturation magnetic flux density to other soft ferrites, when trying to obtain the same characteristics as a bead type noise filter, One had to increase the dimensions.
- the magnetic core 1 when used for noise suppression of signal lines (in particular, power supply lines) 2 where ripple current and surge noise pose a problem, the magnetic core 1 must be further enlarged to prevent magnetic saturation. Due to such a problem, MgZn ferrite is not actually used as a bead-type noise filter.
- the equivalent circuit of the bead-type noise filter is represented by a circuit in which a capacitance C component is connected in parallel to a series circuit of an inductance L component and a resistance R component.
- the inductance L component, the resistance R component, and the capacitance C component are also simply referred to as L component, R component, and C component, respectively.
- L in the frequency band of the signal to be transmitted (signal frequency band), L >> R [L: L component value, R: R component value. Each value represents the impedance IZI value (the same applies hereinafter). ].
- the bead-type noise filter acts as an inductor for the series circuit portion of the L and R components (almost only the L component), and does not cause loss due to the R component to the signal to be transmitted.
- the bead-type noise filter forms a low-pass filter in a circuit with the C component between the signal lines.
- the inductance L component Is small and the cutoff frequency is higher than the frequency band of the signal to be transmitted, so that the signal transmission loss can be ignored.
- the series circuit portion of the L and R components acts as resistance (substantially only the R component), and absorbs noise as heat. Therefore, an effective suppression effect is exhibited especially for unnecessary radiation noise.
- the impedance IZI of the bead type noise filter can be separated into a reactance X component (hereinafter, also simply referred to as X component) and a resistance R component by the following equation (1).
- the complex permeability ⁇ is expressed by the following equation (2).
- the real part 'generates an X component (also called an L component) of the bead-type noise filter
- the imaginary part ⁇ "generates an R component.
- the X component is dominant in the frequency band of the signal to be transmitted, which means that the bead type noise filter acts as a single-pass filter formed by the C component between signal lines, and the noise component superimposed on the signal It is useful for blocking and preventing passage.
- this noise component that has not been cut off and passed through may become a noise component that affects other circuits.
- the R component is dominant in the high frequency band where unwanted radiation noise occurs, and this R component is a factor that converts noise components including unwanted radiation noise into thermal energy and removes it. In this way, converting noise to heat energy and removing the noise can more safely and surely suppress noise as compared with the above-described one-pass filter for blocking noise.
- the frequency at which the magnitudes of both the X and R components are the same is the boundary between which of the components that reflects noise and the components that are converted into thermal energy and removed is larger than the others. Frequency. In general, when removing noise, it is desirable to have a large amount of components that are converted to heat energy and removed. For impedance characteristics, the lower the X-R cross point, the better.
- a bead-type noise filter using the NiZn ferrite as the magnetic core is examined below.
- the R cross point exists at a high frequency band of 10 MHz, and its reactance X component extends to the high frequency band. Therefore, if a bead-type noise filter using NiZn ferrite as the magnetic core is connected to the input signal line of a high-impedance digital circuit having a capacitance of several pF, such as a C-MOS There is a problem that the waveform of the ringing may cause ringing, undershoot, overshoot, or other waveform distortion.
- a bead-type noise filter that does not use NiZn ferrite for the magnetic core has been desired.
- a bead-type noise filter with a lower XR cross-point than when NiZn ferrite was used for the magnetic core was desired.
- a bead-type noise filter that suppresses noise mainly with a safe and reliable R component was desired.
- An object of the present invention has been made in view of the above-mentioned demands, and has been developed so that transmission signals such as digital signals can be manufactured at low cost and in recent years in order to cope with higher frequency and digitalization of signals in electronic devices. It is an object of the present invention to provide a bead-type noise filter that can suppress noise without distorting the waveform.
- the object of the present invention is to significantly increase the specific resistance of inexpensive MnZn ferrite to achieve a high frequency band comparable to that of NiZn ferrite.
- to obtain soft magnetic properties in the present invention is to provide a bead-type noise filter which can be used for the suppression of unnecessary radiation noisyzu having 1 0 number 1 0 0 MH Z.
- the object of the present invention (the invention according to claims 2 and 3) is to achieve a more secure and reliable R component in order to achieve the above object and to suppress noise without distorting the transmission signal waveform.
- An object of the present invention is to provide a high-performance bead-type noise filter that can mainly suppress noise. Disclosure of the invention
- a bead type noise filter that can be used for suppression can be provided. Also, it is possible to provide an inexpensive bead-type noise filter that allows a signal line or power supply line without insulating coating to pass through directly in contact with the magnetic core.
- the beads-type noise filter of the invention described in claim 2 the basic composition, F e 2 0 3: 44. 0 ⁇ 50. Omo 1% ( excluding the 50. Omo 1%;), Z n O:. 4. 0 ⁇ 26 5mo 1% , T i O 2 ⁇ Pi S N_ ⁇ one of the two or two: 0.:! ⁇ 8.
- Omo 1%, MnZn ferrite with the balance being MnO is used for the core (beads core).
- the bead-type noise filter according to the third aspect of the present invention has a basic composition wherein F e 2
- Zn ferrite is used for the magnetic core (bead core).
- FIG. 1 is a perspective view showing an example of a bead type noise filter to which the present invention is applied.
- FIG. 2 is a view similar to that of FIG.
- FIG. 3 is an equivalent circuit diagram of a bead-type noise filter.
- FIG. 4 is a graph showing measurement results of frequency characteristics of impedance in a bead-type noise filter using each sample shown in Table 1 below.
- FIG. 5 is a graph showing the measurement results of the frequency characteristics of impedance in the present invention 1 (bead type noise filter using sample 1) shown in Table 3 below.
- FIG. 6 is a graph showing measurement results of frequency characteristics of impedance in Comparative Example 2 (bead type noise filter using sample 4) shown in Table 3 below.
- a bead-type noise filter according to an embodiment of the present invention will be described with reference to FIGS.
- FIG. 1 shows a bead type noise filter including a magnetic core (bead core) 1 made of a soft magnetic material having a high specific resistance and a signal line (or power supply line, the same applies hereinafter) 2.
- the magnetic core 1 has a cylindrical outer shape, is provided with one through-hole 1a in the axial direction at the center thereof, and the signal line 2 is penetrated into the through-hole 1a to form a bead-type noise filter. ing.
- the present invention has a configuration illustrated in FIGS. 1 and 2, and is applied to a bead-type noise filter having an equivalent circuit illustrated in FIG.
- the F e 2 O 3 which is generally conventionally 5 0. O mo 1% or more containing Mn Z n Fuwera site is inexpensive, and although having good properties, the resistivity is very low. For this reason, this is used for the magnetic core of a bead-type noise filter and cannot be used in a high frequency band.In addition, the signal line must be used directly without an insulating film or insulating coating and in contact with the magnetic core. Was impossible.
- the present inventors have the F e 2 O 3 composition as a 5 0. O mo less than 1%, and by including an appropriate amount of one or more of the T i 0 2 ⁇ Pi S N_ ⁇ 2, It has been clarified that the specific resistance can be significantly increased in Japanese Patent No. 3108803, Japanese Patent No. 310884 and the like.
- the object of the present invention is to provide a safer and more reliable R in order to suppress noise without distorting the transmission signal waveform. It is impossible to provide a high-performance bead-type noise filter capable of suppressing noise mainly by components.
- the XR cross point exists in a high frequency band of 1 OMHz or more, as described later. According to this, since the reactance X component extends to a high frequency band and is large, when such a bead-type noise filter is inserted into the input signal line of a high-impedance digital circuit, the waveform of the input digital signal becomes oversaturated. It causes distortion such as ringing.
- such a bead-type noise filter has a signal wire wound around a magnetic core (bead core) once to penetrate (penetrate one turn). (Coiled signal line)
- the capacitance C component is small.
- the C component can depend on the real part ⁇ 'of the complex relative permittivity of the magnetic core.
- the capacitance C component generated between the winding and the magnetic core becomes very large.
- the C component greatly depends on the real part ⁇ 'of the complex relative permittivity of the magnetic core.
- the present inventors produced a bead-type noise filter using ⁇ ferrite having the same L component and R component, and obtained the following knowledge from the measurement results of the impedance characteristics.
- the real part ⁇ ′ of the complex relative permittivity is large (the C component is large), and the conventional general ⁇ ⁇ ⁇ ⁇ ferrite has the X-R cross point on the low frequency side, but the impedance characteristic at high frequencies
- NiZn ferrite which has a small real part of the complex relative permittivity (small C component)
- has an X-R cross point on the high frequency side but has excellent impedance characteristics at high frequencies.
- the real part ⁇ 'of the complex relative permittivity of the conventional MnZn ferrite ⁇ NiZn ferrite keeps an almost constant value from the low frequency band to the high frequency band. Even so, the width is less than an order of magnitude.
- the present inventors have come to propose a bead-type noise filter using a soft magnetic material for the magnetic core in which the real part ⁇ ′ of the complex relative permittivity changes extremely from low frequency to high frequency. .
- the real part ⁇ ′ of the complex relative permittivity at low frequencies is somewhat large, the X--R cross point exists on the low frequency side, and the real part ⁇ ' of the complex relative permittivity at high frequencies is small, so that It is possible to manufacture a bead-type noise filter that has excellent impedance characteristics at frequencies.
- the magnetic core has a specific resistance of 150 ⁇ or more.
- the real part ⁇ of the complex relative permittivity of the magnetic core is not less than 1,000 and not more than 20,000 at 1 kHz, and not more than 50 at 1 MHz.
- the real part ⁇ ′ of the complex relative permittivity changes greatly from a low frequency to a high frequency
- the X-R cross point of the bead-type noise filter is reduced to a low frequency side, for example, 5 ⁇ Move around ⁇ .
- An embodiment of a bead-type noise filter according to the present invention, in which a signal line is passed through a through hole using a magnetic core of a closed magnetic circuit having the same, will be described.
- Table 1 shows the basic compositions of a magnetic core (sample) using the soft magnetic material according to the embodiment of the present invention and a magnetic core (sample) using the soft magnetic material for comparison.
- Samples 1 to 3 were baked at 1,150 ° C for 3 hours in an atmosphere in which nitrogen was supplied and oxygen partial pressure was controlled. Samples 4 and 5 were fired in air at 1,150 for 3 hours.
- Each of the samples 1 to 5 had a baked shape, an outer shape: 3.2 mm, an inner diameter: 1.6 mm, and: 6 mm.
- Sample 5 which is MgZnFrite, has a low initial magnetic permeability i and a low saturation magnetic flux density Bs, and has no advantage compared to the other Samples 1-4.
- the MgZn ferrite with a low saturation magnetic flux density Bs must have a large core size There is a problem.
- Sample 3 which is a general MnZn ferrite, shows good values for both the initial magnetic permeability ⁇ i and the saturation magnetic flux density B s, but has a very low specific resistance p V and is difficult to use in a high frequency band.
- Sample 3 was a signal without insulating film or coating. The point that the line cannot be used directly in contact with the magnetic core also limits its use.
- Sample 1 core in the invention of claim 2 of MnZn ferrite used as the magnetic core in the present invention
- sample 2 core in the invention of claim 3
- sample 4 of NiZn ferrite were , Initial magnetic permeability ⁇ i, saturation magnetic flux density B s, and specific resistance p V show favorable values.
- Comparative Example 1 As shown in FIG. 4, at higher frequencies than 10 MHz, which is important in noise suppression, the impedance characteristics of Comparative Example 1 are different from those of the present invention (the present inventions 1, 2 and Comparative Examples 2 and 3). Is significantly lower than that of. This is due to the low specific resistance ⁇ V of the MnZn ferrite.
- Comparative Example 3 the impedance characteristics of Comparative Example 3 are lower than those of any of the other bead-type noise filters (Inventive Examples 1 and 2 and Comparative Examples 1 and 2). This is due to the low initial permeability i of MgZnf: lite.
- the impedance characteristics of the present inventions 1 and 2 and Comparative Example 2 show good values in a high frequency band.
- the impedance measured in the production step 2 was separated into a reactance X component and a resistance R component according to the above equation (1).
- both the present inventions 1 and 2 and the comparative example 2 are good, but the waveform of the input digital signal is distorted. It has been found that the present inventions 1 and 2 are superior to the comparative example 2 in that the risk is extremely small.
- the specific resistance is 150 ⁇ or more
- the real part of the complex relative permittivity ⁇ ′ is 1 kHz at 1 kHz.
- the bead type noise filter (the present inventions 1 and 2), which is 32 or 28 in relation to ⁇ 42, has been described, but the real part ⁇ ′ of the complex relative permittivity is not limited to the range described in claim 1. In this case, the same or almost the same effect as that of the above embodiment was obtained.
- the basic yarn of the magnetic core ( ⁇ ferrite) is composed of Fe 2 O 3 : 47.0 m ⁇ 1% and ⁇ ⁇ ⁇ : 10. 5 m ⁇ 1%,
- the bead-type noise filter according to the present invention can easily and inexpensively suppress high-frequency noise radiated from the signal lines of electronic devices due to the trend of electronic devices that have a tendency to be more compact / higher in performance.
- This filter is useful as a filter for noise reduction, and is particularly suitable for suppressing noise without distorting the waveform of the input digital signal.
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- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Coils Or Transformers For Communication (AREA)
- Filters And Equalizers (AREA)
- Soft Magnetic Materials (AREA)
Abstract
Description
Claims
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN038143933A CN1663003A (zh) | 2003-09-22 | 2003-09-22 | 珠形噪声滤波器 |
US10/515,494 US7148767B2 (en) | 2003-09-22 | 2003-09-22 | Bead type noise filter |
EP03816939A EP1569249A1 (en) | 2003-09-22 | 2003-09-22 | Bead noise filter |
PCT/JP2003/012044 WO2005029517A1 (ja) | 2003-09-22 | 2003-09-22 | ビーズ型ノイズフィルタ |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
PCT/JP2003/012044 WO2005029517A1 (ja) | 2003-09-22 | 2003-09-22 | ビーズ型ノイズフィルタ |
Publications (1)
Publication Number | Publication Date |
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WO2005029517A1 true WO2005029517A1 (ja) | 2005-03-31 |
Family
ID=34362504
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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PCT/JP2003/012044 WO2005029517A1 (ja) | 2003-09-22 | 2003-09-22 | ビーズ型ノイズフィルタ |
Country Status (4)
Country | Link |
---|---|
US (1) | US7148767B2 (ja) |
EP (1) | EP1569249A1 (ja) |
CN (1) | CN1663003A (ja) |
WO (1) | WO2005029517A1 (ja) |
Families Citing this family (11)
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US7307495B2 (en) * | 2004-06-17 | 2007-12-11 | Fci Americas Technology, Inc. | Electrical filter assembly having IDC connection |
CN100468930C (zh) * | 2006-03-17 | 2009-03-11 | 鸿富锦精密工业(深圳)有限公司 | 抗电磁干扰电源滤波器的磁珠选择方法 |
US20140241217A1 (en) * | 2011-08-18 | 2014-08-28 | Zte Corporation | Headset device, headset, and method for processing signal by using headset device |
JP6206654B2 (ja) * | 2013-08-30 | 2017-10-04 | セイコーエプソン株式会社 | 液体吐出装置およびヘッドユニット |
JP6206655B2 (ja) | 2013-08-30 | 2017-10-04 | セイコーエプソン株式会社 | 液体吐出装置およびヘッドユニット |
JP6421424B2 (ja) * | 2014-03-07 | 2018-11-14 | 北川工業株式会社 | バスバーアセンブリ、バスバーアセンブリの製造方法 |
DE102014007780A1 (de) | 2014-05-21 | 2015-11-26 | Audi Ag | Energiespeicher, Energiespeicheranordnung für ein Kraftfahrzeug und Kraftfahrzeug |
US9600214B2 (en) | 2014-06-13 | 2017-03-21 | Ricoh Company, Ltd. | Aggregate work volume estimation mechanism |
US9213510B1 (en) | 2014-06-13 | 2015-12-15 | Ricoh Company, Ltd. | Print scheduling mechanism |
CN106021811B (zh) * | 2016-06-08 | 2019-04-02 | 福州大学 | 一种磁性材料宽频复数磁导率测定方法 |
JP6380773B2 (ja) * | 2017-03-27 | 2018-08-29 | セイコーエプソン株式会社 | 液体吐出装置 |
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JP3108803B2 (ja) * | 1998-08-19 | 2000-11-13 | ミネベア株式会社 | Mn−Znフェライト |
JP2003282318A (ja) * | 2002-03-22 | 2003-10-03 | Minebea Co Ltd | 信号弁別器 |
JP2003324014A (ja) * | 2002-04-30 | 2003-11-14 | Minebea Co Ltd | ビーズコア型ノイズフィルタ |
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JPS5636163Y2 (ja) * | 1976-08-19 | 1981-08-26 | ||
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JPS6441202U (ja) | 1987-09-04 | 1989-03-13 | ||
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JPH08181478A (ja) * | 1994-12-26 | 1996-07-12 | Kanegafuchi Chem Ind Co Ltd | ノイズフィルタ及びその製造方法 |
JP3584439B2 (ja) * | 2000-02-08 | 2004-11-04 | ミネベア株式会社 | Mn−Znフェライトおよびその製造方法 |
JP2002167272A (ja) * | 2000-11-28 | 2002-06-11 | Minebea Co Ltd | Mn−Znフェライトの製造方法 |
JP2003059712A (ja) * | 2001-08-10 | 2003-02-28 | Minebea Co Ltd | Mn−Znフェライトおよび巻き線部品 |
JP2003068515A (ja) * | 2001-08-22 | 2003-03-07 | Minebea Co Ltd | Mn−Znフェライトおよび巻き線部品 |
JP2004039787A (ja) * | 2002-07-02 | 2004-02-05 | Minebea Co Ltd | インダクタ |
-
2003
- 2003-09-22 CN CN038143933A patent/CN1663003A/zh active Pending
- 2003-09-22 EP EP03816939A patent/EP1569249A1/en not_active Withdrawn
- 2003-09-22 US US10/515,494 patent/US7148767B2/en not_active Expired - Fee Related
- 2003-09-22 WO PCT/JP2003/012044 patent/WO2005029517A1/ja not_active Application Discontinuation
Patent Citations (6)
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JPS6441202A (en) * | 1987-08-06 | 1989-02-13 | Mitsubishi Petrochemical Co | Cable shielding bead |
JPH05283223A (ja) * | 1992-04-03 | 1993-10-29 | Mitsubishi Electric Corp | 信号弁別器 |
JP3108804B2 (ja) * | 1998-08-19 | 2000-11-13 | ミネベア株式会社 | Mn−Znフェライト |
JP3108803B2 (ja) * | 1998-08-19 | 2000-11-13 | ミネベア株式会社 | Mn−Znフェライト |
JP2003282318A (ja) * | 2002-03-22 | 2003-10-03 | Minebea Co Ltd | 信号弁別器 |
JP2003324014A (ja) * | 2002-04-30 | 2003-11-14 | Minebea Co Ltd | ビーズコア型ノイズフィルタ |
Also Published As
Publication number | Publication date |
---|---|
US20060055487A1 (en) | 2006-03-16 |
EP1569249A1 (en) | 2005-08-31 |
US7148767B2 (en) | 2006-12-12 |
CN1663003A (zh) | 2005-08-31 |
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