KR101883011B1 - Filter for Removing Noise - Google Patents

Abstract

The present invention relates to a lower coil layer in which a lower primary coil and a lower secondary coil are wound in parallel to each other; An upper coil layer having an upper secondary coil disposed on an upper portion of the lower primary coil and an upper primary coil disposed on an upper portion of the lower secondary coil; And a lower secondary coil interposed between the lower coil layer and the upper coil layer, wherein the lower primary coil and the upper primary coil, the lower secondary coil and the upper secondary coil are connected to the upper and lower coil layers Disclosed is a noise elimination filter comprising first and second vias electrically and serially alternately connected in series.
According to the present invention, it is possible to realize high common mode impedance at the same frequency, improve performance and capacity, and reduce manufacturing cost and productivity by simplifying structure and process.

Description

Filter for Removing Noise [

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a noise canceling filter, and more particularly, to a noise canceling filter capable of realizing high common mode impedance at the same frequency and improving insertion loss to improve performance and capacity.

Electronic products such as digital TVs, smart phones, laptops, etc. are widely used for data transmission and reception in high frequency bands. In the future, these IT electronic products will be connected not only to one device but also to each other via USB and other communication ports, The frequency of use is expected to be high.

Here, in order to rapidly transmit and receive the data, the frequency band of the MHz band shifts to the high frequency band of the GHz band, and data is exchanged through a larger amount of internal signal lines.

In order to transmit and receive such a large amount of data, there is a problem in processing smooth data due to signal delays and other noises in transmission and reception of a high frequency band of GHz band between a main device and a peripheral device.

In order to solve this problem, the EMI countermeasure parts are provided around the connection between the IT and the peripheral device. However, the conventional EMI countermeasures are the wire wound type and the laminate type, and the chip parts are large in size and have poor electrical characteristics. Therefore, it is required to provide EMI countermeasures for the slimming, miniaturization, integration and multifunctionalization of electronic products.

Hereinafter, the common mode filter of the EMI countermeasure coil component according to the related art, that is, the noise removing filter according to the related art will be described in more detail with reference to FIGS. 1 to 3. FIG.

1, the conventional common mode filter includes a first magnetic substrate 1 and a first coil pattern 2a and a second coil pattern 2b provided on the magnetic substrate 1, And a second magnetic substrate 3 provided on the insulating layer 2. The second magnetic substrate 3 is formed on the insulating layer 2,

Here, the insulating layer 2 is formed on the first magnetic substrate 1 so that the first coil pattern 2a and the second coil pattern 2b are formed inside through a thin film process. An example of the thin film process is disclosed in Japanese Patent Application Laid-Open No. 8-203737.

The second magnetic substrate 3 is provided on the insulating layer 2 via a bonding layer 4 in a bonding manner.

The outer electrode 5 is provided to surround both ends of the laminate including the first magnetic substrate 1, the insulating layer 2 and the second magnetic substrate 3, And is electrically connected to the first coil pattern 2a and the second coil pattern 2b through a lead wire (not shown).

The conventional common mode filter configured as described above is configured to remove the noise in the common mode and to smoothly pass the signal in the differential mode, the first coil pattern 2a and the second coil pattern 2b facing each other in the up and down direction.

More specifically, as shown in FIG. 2, in the case of common mode noise, magnetic fluxes generated by the current flow of the first coil pattern 2a and the second coil pattern 2b are mutually different from each other It can not be passed because it has a large impedance, and in the case of the differential mode signal, the magnetic fluxes cancel each other and smoothly pass.

However, in the conventional common mode filter, as the frequency increases, even in the differential mode, there is a problem that the impedance increases and insertion loss occurs.

That is, the magnetic fluxes flowing between the first coil pattern 2a and the second coil pattern 2b are strengthened with each other, and the impedance increases in the differential mode according to the increase of the frequency, thereby increasing the insertion loss.

In particular, the greater the distance between the first coil pattern 2a and the second coil pattern 2b, the greater the impedance in the differential mode and the greater the insertion loss. As a result, do.

In the conventional common mode filter, since the second magnetic substrate 3 is bonded to the insulating layer 2 via the adhesive layer 4, the flow of magnetic flux is blocked by the non-magnetic property of the adhesive layer 4 And there is a problem that rapid characteristic deterioration is caused.

In order to improve this, the length of the first coil pattern 2a and the second coil pattern 2b may be increased. In this case, however, the manufacturing cost of the noise removing filter is increased and the size of the noise removing filter is increased There were disadvantages.

SUMMARY OF THE INVENTION The present invention has been conceived to solve the problems described above, and it is an object of the present invention to provide a high-frequency noise elimination circuit which can realize high common mode impedance at the same frequency, reduce impedance in a differential mode, And to provide a filter.

Another object of the present invention is to provide a noise canceling filter capable of minimizing an increase in size of a product accompanied by increase in performance and capacity.

In order to achieve the above-mentioned object, the present invention is characterized by: a lower coil layer in which a lower primary coil and a lower secondary coil are wound in parallel; An upper coil layer having an upper secondary coil disposed on an upper portion of the lower primary coil and an upper primary coil disposed on an upper portion of the lower secondary coil; And a lower secondary coil interposed between the lower coil layer and the upper coil layer, wherein the lower primary coil and the upper primary coil, the lower secondary coil and the upper secondary coil are connected to the upper and lower coil layers And a first via and a second via which are electrically connected in series in succession.

Here, the lower primary coil and the upper primary coil, and the lower secondary coil and the upper secondary coil may have a continuous spiral shape from the inner side to the outer side.

The noise removing filter may include a lower magnetic body provided below the lower coil layer and an upper magnetic body provided above the upper coil layer; At this time, the upper magnetic body may extend to the center of the lower coil layer.

The noise removing filter may include a lower insulating layer covering the lower primary and secondary coils, and an upper insulating layer covering the upper primary and secondary coils; At this time, the lower insulating layer may include a primary coating layer covering the lower primary and secondary coils, and a secondary coating layer for planarizing the upper surface of the primary coating layer.

It is preferable that the horizontal width of the lower primary coil and the secondary coil is larger than the horizontal width of the upper primary coil and the secondary coil.

At this time, the horizontal width of the innermost coil and the outermost coil of the lower primary and secondary coils may be larger than the horizontal width of the coil positioned between the innermost coil and the outermost coil.

As described above, according to the noise canceling filter of the present invention, it is possible to realize high common mode impedance at the same frequency, reduce the impedance in the differential mode, and improve the insertion loss to improve the characteristics and performance of the noise canceling filter There is an advantage.

According to the noise elimination filter of the present invention, there is an advantage that the capacity of the noise elimination filter can be improved.

1 is a cross-sectional view schematically showing a common mode filter of a conventional noise reduction filter.
FIG. 2 is a schematic view showing a magnetic flux by a primary coil pattern and a secondary coil pattern of FIG. 1; FIG.
3 is a perspective view schematically showing an embodiment of a noise removing filter according to the present invention.
Figure 4 is a cross-sectional view of Figure 3;
5 is a cross-sectional view taken along line I-I 'of FIG.
FIG. 6A is a plan view schematically showing the input side lead portion of the lower primary coil of FIG. 3; FIG.
FIG. 6B is a plan view schematically showing the output side lead portions of the lower primary, secondary, and lower secondary coils of FIG. 3; FIG.
Fig. 6C is a plan view schematically showing the output side lead portions of the upper primary coil and the upper primary coil of Fig. 3; Fig.
FIG. 7 is a schematic diagram showing a magnetic flux generated by a lower primary coil and an upper primary coil applied to a noise removing filter according to the present invention. FIG.
8A is a graph illustrating impedance characteristics of a conventional noise filter and an impedance characteristic of a conventional common mode filter according to an embodiment of the present invention.
8B is a graph showing an insertion loss characteristic of a conventional noise filter according to an embodiment of the present invention and a conventional common mode filter.
9A and 9B are process drawings schematically showing a process of forming a lower insulating layer covering lower primary and secondary coils,
9A is a view showing a state in which a primary coating layer is formed on lower primary and secondary coils,
FIG. 9B is a view showing a state in which a secondary coating layer is formed on the primary coating layer of FIG. 9A. FIG.
10 is a cross-sectional view schematically showing another form of the lower primary coil and the secondary coil applied to the noise canceling filter according to the present invention.

Preferred embodiments of the present invention in which the object of the present invention can be specifically realized will be described with reference to the accompanying drawings. In describing the present embodiment, the same designations and the same reference numerals are used for the same components, and additional description thereof will be omitted in the following.

Hereinafter, an embodiment of the noise canceling filter according to the present invention will be described in more detail with reference to FIGS. 3 to 12.

FIG. 3 is a perspective view schematically showing an embodiment of the noise canceling filter according to the present invention, FIG. 4 is a cross-sectional view of FIG. 3, FIG. 5 is a sectional view taken along the line I- 3 is a plan view schematically showing the input side lead portion of the lower primary coil and the secondary coil of FIG. 3, FIG. 6B is a plan view schematically showing the output side lead portion of the lower primary coil and the lower secondary coil of FIG. 3, And an output side lead portion of the upper primary coil and the upper primary coil.

FIG. 7 is a schematic view illustrating a magnetic flux generated by a lower primary coil and an upper primary coil applied to a noise removing filter according to the present invention. FIG. FIG. 8B is a graph showing a comparison between an embodiment of a noise elimination filter and an impedance characteristic of a conventional common mode filter, FIG. 8B is a graph showing an insertion loss characteristic of a conventional common mode filter, to be.

9A and 9B are schematic views illustrating a process of forming a lower insulating layer covering lower primary and secondary coils. FIG. 9A is a view showing a state in which a primary coating layer is formed on lower primary and secondary coils And FIG. 9B is a view showing a state in which a secondary coating layer is formed on the primary coating layer of FIG. 9A.

10 is a cross-sectional view schematically showing another form of a lower primary coil and a secondary coil applied to the noise canceling filter according to the present invention.

3 to 6C, an embodiment of a noise removing filter 100 according to the present invention includes a lower magnetic body 110, a coil layer 130 provided on the lower magnetic body 110, And an upper magnetic body 160 provided on the coil layer 130.

The lower magnetic body 110 may be formed in the form of a substrate made of ferrite magnetic material.

The coil layer 130 includes a lower coil layer in which a lower primary coil 121 and a lower secondary coil 122 are wound in parallel to each other and an upper secondary coil 121 disposed at an upper portion of the lower primary coil 121. [ A coil 142 and an upper primary coil 141 disposed on top of the lower secondary coil 122 may include an upper coil layer wound in parallel.

Here, the lower coil layer may include a lower insulating layer 131 covering the lower primary coil 121 and the lower secondary coil 122, and the upper coil layer may include the upper primary coil 121 And an upper insulating layer 132 covering the upper secondary coil 142.

At this time, the lower insulating layer 131 and the upper insulating layer 132 may be formed of the same material and may be formed as one insulating layer.

The noise elimination filter 100 of the present embodiment is disposed between the lower coil layer and the upper coil layer and includes the lower primary coil 121 and the upper primary coil 141, A first via 151 electrically connected to the lower coil layer in an alternating manner and a second via 151 alternately connected to the upper and lower coil layers per single winding in the lower secondary coil 122 and the upper secondary coil 142, And a second via 152 that electrically connects to the second via 152 in series.

Accordingly, the lower primary coil 121 and the upper primary coil 141 may have a continuous spiral shape from the inner side to the outer side, and the lower secondary coil 122 and the upper secondary coil (142) may also have a continuous spiral shape from the inner side to the outer side.

In the noise elimination filter 100 of the present embodiment, the lower primary coil 121 and the lower secondary coil 122 are provided on the same layer, and the upper primary coil 141 and the upper secondary coil Coils 142 are provided on the same layer. The lower primary coil 121 and the upper primary coil 141 are alternately and continuously provided in the upper and lower coil layers per single winding through the first vias 151, (122) and the upper secondary coil (142) are alternately and continuously provided in the upper and lower coil layers per single winding through the second via (152).

The electric input lead patterns 121a and 122a of the upper and lower primary coils 141 and 121 and the upper and lower secondary coils 142 and 122 may be provided on the same layer, Each of the electrical output lead patterns 141b and 122b may be provided on a different layer from among the upper and lower insulating layers 131 and 132.

On the other hand, in the noise elimination filter 100 of the present embodiment, the primary pattern and the secondary pattern are provided on the same horizontal layer, that is, the lower primary coil 121 and the lower secondary coil 122 are disposed on the same horizontal layer And the upper primary coil 141 and the upper secondary coil 142 are provided alternately on the same horizontal layer so that the lower primary and secondary coils 121 and 122 and The magnetic fluxes flowing between the upper and the lower primary and secondary coils 141 and 142 cancel each other to lower the impedance in the differential mode and thereby reduce the insertion loss and improve the characteristics of the noise canceling filter.

That is, as shown in FIGS. 8A and 8B, the characteristics of the conventional common mode filter and the noise canceling filter 100 of the present embodiment are simulated. As a result, in the present embodiment, the impedance of the differential mode is lowered, It can be confirmed that the loss is improved.

9A and 9B, the lower insulating layer 131 covering the lower primary and secondary coils 121 and 122 of the noise canceling filter 100 of the present embodiment includes a primary coating layer 131a, And a secondary coating layer 131b for planarizing the upper surface of the primary coating layer 131a.

That is, when the lower insulating layer 131 for covering the lower primary coil 121 and the lower secondary coil 122 is formed by a single coating, concaves and convexes may be formed on the upper surface of the lower insulating layer 130, It is difficult to form the upper primary and secondary coils 141 and 142 on the upper surfaces of the lower primary and secondary coils 121 and 122 in the correct positions and shapes.

9B, the secondary coating layer 131b is formed on the primary coating layer 131a having the concavo-convex shape on the upper surface to form the lower insulating layer 131 covering the lower primary and secondary coils 121 and 122, So that the upper primary coil 141 and the upper secondary coil 142 can be precisely formed on the upper portions of the lower primary coil 121 and the lower secondary coil 122, respectively.

Even though the lower insulating layer 131 covering the lower primary and secondary coils 121 and 122 is formed through two coating processes, the region where the lower primary and secondary coils 121 and 122 are not formed That is, coating may not be performed on the innermost and uppermost outermost surfaces of the lower insulating layer 131. Accordingly, the upper and the lower secondary coils 141 and 142 located in the non- Can be switched.

Therefore, as shown in FIG. 10, the widths of the lower primary and secondary coils 121 and 122 can be larger than the widths of the upper primary coil 141 and the upper secondary coil 142.

In particular, the widths of the innermost and outermost patterns of the lower primary and secondary coils 121 and 122 may be greater than the width of the pattern located between the innermost pattern and the outermost pattern.

The upper magnetic body 160 may be formed by filling a ferrite magnetic material on the upper and the lower primary and secondary coils 141 and 142. Although not shown in detail, The first and second coils 121 and 122 can be extended to the center of the lower primary and secondary coils 121 and 122, respectively.

Therefore, the performance and characteristics of the noise canceling filter 100 of the present embodiment can be improved by improving the magnetic flux density due to the extension of the upper magnetic body 160.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, and that various changes, substitutions and alterations can be made therein without departing from the spirit and scope of the invention. However, it should be understood that such substitutions, changes, and the like fall within the scope of the following claims.

100: An embodiment of a noise removing filter 110:
121, 122: Lower primary and secondary coils 130: Coil layer
131: lower insulating layer 132: upper insulating layer
141, 142: upper and secondary coils 151, 152: first and second vias
160: upper magnetic body

Claims (6)

A lower coil layer wound in parallel with the lower primary coil and the lower secondary coil;
An upper coil layer having an upper secondary coil disposed on an upper portion of the lower primary coil and an upper primary coil disposed on an upper portion of the lower secondary coil; And
Wherein the lower primary coil and the upper primary coil and the lower secondary coil and the upper secondary coil are interposed between the lower coil layer and the upper coil layer, A first via and a second via electrically connected in series to each other,
A lower insulating layer covering the lower primary and secondary coils, and an upper insulating layer covering the upper primary and secondary coils,
Wherein the lower insulating layer includes a primary coating layer covering the lower primary and secondary coils and a secondary coating layer for planarizing an upper surface of the primary coating layer,
Wherein a horizontal width of the lower primary coil and the lower secondary coil is greater than a horizontal width of the upper primary coil and the secondary coil.
The method according to claim 1,
Wherein the lower primary coil, the upper primary coil, the lower secondary coil, and the upper secondary coil have a spiral shape continuous from the inner side to the outer side.
The method according to claim 1,
A lower magnetic body provided below the lower coil layer, and an upper magnetic body provided above the upper coil layer; And the upper magnetic body extends to the center of the lower coil layer.
delete delete The method according to claim 1,
Wherein the horizontal width of the innermost coil and the outermost coil of the lower primary coil is greater than the horizontal width of the coil located between the innermost coil and the outermost coil.

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