KR20120059680A - Common Mode Filter for HDMI - Google Patents

Abstract

PURPOSE: A common mode filter for an HDMI is provided to minimize the efficiency reduction of a magnetic body while obtaining insulating effect by printing a dielectric seat forming an insulating layer on an electrode part. CONSTITUTION: A common mode filter for an HDMI comprises a base layer(120), a first pattern layer(140), a second pattern layer(160), and a protective layer(180). Dielectrics(125,185) formed for insulation of electrode patterns(122,182) and magnetic sheets(126,186) are formed in the base layer and the protective layer in the same size and shape as the electrode patterns. The dielectrics can be printed larger than the electrode patterns in a set range according to the size and shape of the electrode patterns.

Description

Common Mode Filter for HDMD {Common Mode Filter for HDMI}

The present invention relates to a common mode filter, and more particularly, to a common mode filter for HDMI that minimizes the reduction of the effect of the magnetic material while ensuring insulation.

As technology advances, electronic devices such as mobile phones, home appliances, PCs, PDAs, LCDs, etc. are changing from analog to digital, and the speed of data is increasing due to an increase in the amount of data processed.

However, digitized and accelerated electronics are sensitive to external stimuli. That is, when a small abnormal voltage and high frequency noise from outside enters the internal circuit of the electronic device, the circuit may be broken or the signal may be distorted. At this time, the circuit of the electronic device, the abnormal voltage and noise causing the signal distortion, such as lightning strike, electrostatic discharge charged to the human body, switching voltage generated in the circuit, power supply noise included in the power supply voltage, unnecessary electromagnetic signals or Electromagnetic noise.

In order to prevent circuit breakage and signal distortion of the electronic device, a filter is provided to prevent abnormal voltage and high frequency noise from flowing into the circuit. In general, a common mode filter is used for high speed differential signal lines to remove common mode noise.

Common-mode noise is noise that occurs on differential signal lines, and common-mode filters remove noise that cannot be eliminated with conventional EMI filters. The common mode filter contributes to the improvement of EMC characteristics of home appliances or antenna characteristics of mobile phones.

Such common mode filters can be applied to USB, MDDI / MIPI, and HDMI. In particular, the market expansion of HDMI makes common mode filters the best solution in this market.

Currently, there are three main requirements for common mode filters in the HDMI market. The first requirement is miniaturization and slimness, for example 2.0 mm x 1.0 mm (2 pole), 1.2 mm x 1.0 mm (1 pole). The second requirement requires that the common mode impedance in the low frequency band of 100 MHz should be around 65-115, and the differential mode impedance should be up to 15 Ω. The third requirement is that the IR characteristic should be kept above 10 Hz and the cut-off frequency band should be above 3 Hz.

In order to satisfy these requirements, researches on common mode filters for multilayer and thin film HDMI have been conducted.

In the case of a multi-layered common mode filter, as illustrated in FIG. 1, the insulating layer 10 is formed on and under the pattern (that is, the in-pattern 20 and the spiral pattern 30). Ensure insulation properties. In this case, in order to increase the common mode impedance, a structure for forming the insulating layer 10 using a magnetic material has been studied.

However, in the case of forming the insulating layer using a magnetic material, there are problems that it is difficult to realize the characteristics of insulation resistance of 10 MΩ or more, which is required in the HDMI market, since several insulation resistances are formed.

In addition, in the case of a thin film type common mode filter, as illustrated in FIG. 2, a common mode filter having a high frequency characteristic by configuring a three-layer structure having the pattern 40 at the center has been studied. In this case, a plurality of magnetic bodies 50 are formed outside the pattern.

However, in the case of the thin film common mode filter, expensive manufacturing equipment and manufacturing cost are generated, and heat deformation during the SMT process and rework may occur.

SUMMARY OF THE INVENTION The present invention has been proposed in view of the above-mentioned conventional problems, and an object thereof is to provide a common mode filter for HDMI for forming an insulating layer by printing a dielectric on an electrode portion.

In order to achieve the above object, a common mode filter for HDMI according to an embodiment of the present invention, a magnetic sheet; An electrode pattern printed and formed on an upper surface of the magnetic sheet; And a base layer formed of a dielectric printed and formed between the magnetic sheet and the electrode pattern, wherein the dielectric is formed only at a portion where the electrode pattern is formed on the upper surface of the magnetic sheet.

An electrode pattern is formed on the top of the dielectric sheet by printing, and further includes a first pattern layer stacked on the base layer.

An electrode pattern is printed and formed on the dielectric sheet, and further includes a second pattern layer stacked on the first pattern layer.

Dielectric sheets; An electrode pattern printed on the upper surface of the dielectric sheet;

A dielectric formed by being printed on the upper surface of the electrode pattern; And a protective layer composed of a magnetic sheet printed and formed on an upper portion of the dielectric and stacked on an upper portion of the second pattern layer, wherein the dielectric is formed by being printed only on a portion where an electrode pattern is formed on a lower surface of the magnetic sheet.

A dielectric sheet printed and formed on the electrode pattern of the base layer; And a first pattern layer formed of an electrode pattern printed and formed on the dielectric sheet.

A dielectric sheet printed and formed on the electrode pattern of the first pattern layer; And a second pattern layer formed of an electrode pattern printed and formed on the dielectric sheet.

A dielectric sheet printed and formed on the electrode pattern of the second pattern layer; An electrode pattern printed on the upper surface of the dielectric sheet; A dielectric formed by being printed on the upper surface of the electrode pattern; And a protective layer formed of a magnetic sheet printed and formed on an upper portion of the dielectric, wherein the dielectric is printed and formed only on a portion where an electrode pattern is formed on a lower surface of the magnetic sheet.

The dielectric is formed in the same size and shape as the electrode pattern.

The dielectric is formed larger within the set range than the electrode pattern.

In order to achieve the above object, a common mode filter for HDMI according to another embodiment of the present invention, a magnetic sheet; A dielectric formed by printing on the upper surface of the magnetic sheet; An electrode pattern printed and formed on an upper surface of the dielectric; And a base layer formed of a dielectric sheet printed and formed on an upper portion of the electrode pattern, wherein the magnetic sheet is spaced apart from the electrode pattern on the outer side and the center of the upper surface to form a magnetic body, and the dielectric is formed only at a portion where the electrode pattern is formed. .

Magnetic sheet; A dielectric formed on top of the magnetic sheet; An electrode pattern printed and formed on the dielectric; And a first pattern layer composed of a dielectric sheet printed and formed on an upper portion of the electrode pattern, the first pattern layer stacked on an upper portion of the protective layer, wherein the magnetic sheet is spaced apart from the electrode pattern on the outer side and the center of the upper surface to form a magnetic body. Is formed only in the portion where the electrode pattern is formed.

Magnetic sheet; A dielectric formed on top of the magnetic sheet; An electrode pattern printed and formed on the dielectric; And a second pattern layer composed of a dielectric sheet printed and formed on the upper part of the electrode pattern, the second pattern layer stacked on the first pattern layer. The dielectric is formed only at the portion where the electrode pattern is formed.

Electrode patterns; A dielectric formed by being printed on the electrode pattern; It further comprises a protective layer composed of a magnetic sheet printed and formed on the upper portion of the dielectric layer is laminated on the upper portion of the second pattern layer, the magnetic body is formed on the outer side and the center of the lower surface of the magnetic sheet to be spaced apart from the electrode pattern. Only the part where the pattern is formed is printed and formed.

A magnetic sheet printed and formed on the dielectric sheet of the base layer; A dielectric formed on top of the magnetic sheet; An electrode pattern printed and formed on the dielectric; And a first pattern layer including a dielectric sheet printed and formed on an upper portion of the electrode pattern, wherein the magnetic sheet is spaced apart from the electrode pattern on an outer side and a central portion of the upper surface to form a magnetic body, and the dielectric portion is a portion where the electrode pattern is formed. Only formed.

A magnetic sheet printed and formed on the dielectric sheet of the first pattern layer; A dielectric formed on top of the magnetic sheet; An electrode pattern printed and formed on the dielectric; And a second pattern layer including a dielectric sheet printed and formed on an upper portion of the electrode pattern, wherein the magnetic sheet is spaced apart from the electrode pattern at an outer side and a center of the upper surface to form a magnetic body, and the dielectric portion is a portion where the electrode pattern is formed. Only formed.

An electrode pattern printed and formed on the dielectric sheet of the second pattern layer; A dielectric formed by being printed on the electrode pattern; And a protective layer formed of a magnetic sheet printed and formed on an upper portion of the dielectric, wherein a magnetic body is formed at an outer side and a center of the magnetic sheet to be spaced apart from the electrode pattern, and the dielectric is formed only at a portion where the electrode pattern is formed. .

The dielectric is formed in the same size and shape as the electrode pattern.

The dielectric is formed larger within the set range than the electrode pattern.

The common mode filter for HDMI according to the present invention is formed by printing a dielectric sheet constituting the insulating layer on the electrode portion, thereby ensuring an insulating layer and minimizing the reduction of the effect of the magnetic material.

Incidentally, the common mode filter for HDMI increases the common mode impedance, thereby minimizing and reducing the size of the common mode filter by minimizing the length of the pattern, and improving the high frequency characteristics.

In addition, the common mode filter for HDMI is formed by printing a dielectric sheet constituting the insulating layer on the electrode part, so that the firing temperature can be increased as compared with the conventional common mode filter, thereby increasing the common mode impedance and the differential mode SRF impedance. In addition, the magnetic permeability is increased to increase the impedance of the common mode and the SRF impedance of the differential mode.

In addition, the common mode filter for HDMI prints the magnetic material on the upper and outer sides and the core of the magnetic sheet so that the upper and lower parts, the left part, the right part, and the center part of the electrode pattern are affected so that the magnetic effect is applied to the upper and lower parts of the electrode pattern. The common mode impedance is increased and the punching and casting processes are omitted, compared to the conventional one provided only in the direction, thereby reducing the facility investment cost.

1 and 2 are diagrams for explaining a conventional common mode filter for HDMI.
3 is a diagram for explaining the structure of a common mode filter for HDMI according to a first embodiment of the present invention;
4 and 5 are views for explaining the base layer of FIG.
FIG. 6 is a view for explaining a first pattern layer of FIG. 3. FIG.
FIG. 7 is a diagram for describing a second pattern layer of FIG. 3. FIG.
8 and 9 are views for explaining the protective layer of FIG.
11 and 12 are views for comparing and explaining the characteristics of the common mode filter for HDMI and the conventional common mode filter for HDMI according to the first embodiment of the present invention.
13 to 14 are diagrams for explaining characteristics according to firing temperature of a common mode filter for HDMI according to a first embodiment of the present invention.
FIG. 15 is a diagram for explaining cutoff frequency characteristics of a common mode filter for HDMI according to a first embodiment of the present invention.
16 is a diagram for explaining the structure of a common mode filter for HDMI according to a second embodiment of the present invention;
FIG. 17 is a view for explaining a base layer of FIG. 16; FIG.
FIG. 18 is a diagram for explaining a first pattern layer of FIG. 16. FIG.
FIG. 19 is a diagram for describing a second pattern layer of FIG. 16. FIG.
20 is a view for explaining a protective layer of FIG. 16;

Hereinafter, the preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the technical idea of the present invention. . First of all, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are used as much as possible even if displayed on different drawings. In addition, in describing the present invention, when it is determined that the detailed description of the related well-known configuration or function may obscure the gist of the present invention, the detailed description thereof will be omitted. Embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art. Accordingly, the shape and size of elements in the drawings may be exaggerated for clarity.

First, before describing an embodiment of the present invention, the features of the common mode filter for HDMI of the present invention will be described.

Conventionally, in order to form a base layer located at the lowermost part of the common mode filter for HDMI, LTCC interlayer is laminated on the upper surface of the magnetic sheet (for example, ferrite sheet), and an electrode pattern is laminated on the LTCC interlayer. In the case of the protective layer, the electrode pattern is laminated on the upper surface of the LTCC sheet, the LTCC interleaf paper is laminated on the upper electrode pattern, and the magnetic sheet (eg, ferrite sheet) is laminated on the upper surface of the LTCC interleaf paper.

At this time, an LTCC interlayer, which is a dielectric, is laminated between the magnetic sheet and the electrode pattern to form an insulating layer. Here, the LTCC interlayer formed between the magnetic sheet and the electrode pattern is formed to have a size covering all of the upper surface (or lower surface) of the magnetic sheet. That is, regardless of the size of the electrode pattern is formed to have the same area as the upper surface of the magnetic sheet to cover all the magnetic sheet.

However, when a dielectric sheet having the same area as the magnetic sheet (that is, LTCC interlayer) is used, the influence of the magnetic properties of the magnetic sheet on the electrode pattern by the dielectric sheet is reduced. That is, the dielectric sheet blocks the transfer of the magnetic properties of the magnetic sheet to the electrode pattern.

The common mode filter for HDMI according to the present invention forms an area of the dielectric formed between the magnetic sheet and the electrode pattern in the same manner as the electrode pattern in order to minimize the blocking of the transfer of the magnetic property to the electrode pattern. That is, by forming a dielectric having the same size as the electrode pattern between the magnetic sheet and the electrode pattern, it is characterized in that the transmission of the magnetic properties to the electrode pattern is minimized.

Of course, the dielectric printed between the magnetic sheet and the electrode pattern may be larger than the electrode pattern within the set range. Here, since the setting range may be set differently according to the size and shape of the electrode pattern, the setting range is not limited.

(Embodiment 1)

Hereinafter, the common mode filter for HDMI according to the first embodiment of the present invention will be described in detail with reference to the accompanying drawings. 3 is a view for explaining the structure of a common mode filter for HDMI according to a first embodiment of the present invention. 4 and 5 are views for explaining the base layer of FIG. 3, FIG. 6 is a view for explaining the first pattern layer of FIG. 3, and FIG. 7 is a view for explaining the second pattern layer of FIG. 8 and 9 are diagrams for describing the protective layer of FIG. 3.

As shown in FIG. 3, the common mode filter 100 for HDMI includes a base layer 120, a first pattern layer 140, a second pattern layer 160, and a protective layer 180. Here, the common mode filter 100 for HDMI is divided into a base layer 120, a first pattern layer 140, a second pattern layer 160, and a protective layer 180 for convenience of description. The mode filter 100 is manufactured by printing the components included in each layer. In particular, the dielectric layers 125 and 185 formed on the base layer 120 and the protective layer 180 to insulate the magnetic sheets 126 and 186 and the electrode patterns 122 and 182 may be formed of the electrode patterns 122 and 182. Characterized in that the same size and shape. Of course, the dielectrics 125 and 185 may be printed larger than the electrode patterns 122 and 182 within a set range. Here, since the setting range may be set differently according to the size and shape of the electrode patterns 122 and 182, the setting range is not limited.

The base layer 120 is located at the bottom. The base layer 120 is formed by printing a dielectric 125 and an electrode pattern 122 on an upper surface of a sheet made of a magnetic material (eg, ferrite). That is, as shown in FIG. 4, the magnetic sheet 126 is disposed at the bottom of the base layer 120. The dielectric 125 is printed on the upper surface of the magnetic sheet 126. In this case, the dielectric 125 is mainly used of glass, and is printed in the same size and shape as the electrode pattern 122 printed on the dielectric 125. Of course, the dielectric 125 formed between the magnetic sheet 126 and the electrode pattern 122 may be printed larger than the electrode pattern 122 within the set range. Here, since the setting range may be set differently according to the size and shape of the electrode pattern 122, the range is not limited. The electrode pattern 122 is printed on the top surface of the dielectric 125. In this case, the lead electrode 123 exposed to the outside is formed at one end of the electrode pattern 122, and the electrode pattern 142 of the first pattern layer 140 is formed at the other end of the electrode pattern 122. A lead electrode 124 connected to the lead electrode 146 is formed.

The base layer 120 may have a core 127 made of a magnetic material at a central portion thereof. Here, as shown in FIG. 5, the base layer 120 includes a dielectric 121 for facilitating printing of the first pattern layer 140 on the top surface on which the dielectric 125 and the electrode pattern 122 are formed. LTCC) may be printed. That is, the dielectric 121 is additionally printed on the upper surface of the magnetic sheet 126 on which the dielectric 125 and the electrode pattern 122 are formed to facilitate printing of the first pattern layer 140.

The first pattern layer 140 is positioned on the base layer 120. The first pattern layer 140 is formed by printing an electrode pattern 142 on the top surface of the sheet 141 made of a dielectric (eg, LTCC). That is, as shown in FIG. 6, the first pattern layer 140 is formed by printing a spiral electrode pattern 142 on the upper surface of the dielectric sheet 141. In this case, the lead electrode 144 exposed to the outside is formed at one end of the electrode pattern 142, and the electrode pattern 122 of the base layer 120 (that is, the lead electrode 124 of the base layer 120) is formed at the other end thereof. A lead electrode 146 connected to the)) is formed. Here, the core 147 of the magnetic material may be formed in the center of the dielectric sheet 141 (that is, inside the electrode pattern 142). A dielectric (eg, LTCC) (not shown) may be printed on the first pattern layer 140 on the electrode pattern 142.

The first pattern layer 140 may be formed by printing a spiral electrode pattern 142 on the upper surface of the base layer 120 without using a separate dielectric sheet 141. That is, when a dielectric (eg, LTCC) is printed on the top surface of the base layer 120, the first pattern layer 140 may be formed by printing a spiral electrode pattern 142 on the top surface of the base layer 120. It may be.

The second pattern layer 160 is positioned on the first pattern layer 140. The second pattern layer 160 is formed by printing an electrode pattern 162 on the top surface of the sheet 161 made of a dielectric (eg, LTCC). That is, as shown in FIG. 7, the second pattern layer 160 is formed by printing a spiral electrode pattern 162 on the upper surface of the dielectric sheet 161. At this time, the lead electrode 164 exposed to the outside is formed at one end of the electrode pattern 162, and the electrode pattern 182 of the protective layer 180 (ie, the lead electrode 184 of the protective layer 180) is formed at the other end. A lead electrode 166 connected to the)) is formed. Here, the core 167 of the magnetic material may be formed in the center of the dielectric sheet 161 (that is, inside of the electrode pattern 162). A dielectric (eg, LTCC) may be printed on the second pattern layer 160 on the electrode pattern 162.

The second pattern layer 160 may be formed by printing an electrode pattern 162 on an upper surface of the first pattern layer 140. That is, the second pattern layer 160 may be formed by printing a spiral electrode pattern 162 on the top surface of the first pattern layer 140 on which the dielectric (eg, LTCC) is printed.

The passivation layer 180 is positioned on the second pattern layer 160. The protective layer 180 is formed by printing an electrode pattern 182, a dielectric 185, and a magnetic sheet (eg, ferrite) material 186 on a top surface of the sheet 181 formed of a dielectric (eg, LTCC). That is, as shown in FIG. 8, the protective layer 180 forms an electrode pattern 182 on the top surface of the dielectric sheet 181. At this time, one end of the electrode pattern 182 is formed with the extraction electrode 184 exposed to the outside, the other end of the electrode pattern 162 of the second pattern layer 160 (that is, of the second pattern layer 160) A lead electrode 183 connected to the lead electrode 166 is formed. The dielectric 185 is printed on the top surface of the electrode pattern 182. In this case, the dielectric 185 is mainly glass, and is printed in the same size and shape as the electrode pattern 182 printed on the dielectric sheet 181. Of course, the dielectric 185 formed between the magnetic sheet 186 and the electrode pattern 182 may be printed larger than the electrode pattern 182 within the set range. Here, since the setting range may be set differently according to the size and shape of the electrode pattern 182, the setting range is not limited. The magnetic sheet 186 is printed on the top surface of the dielectric sheet 181 to cover the electrode pattern 182 and the dielectric 185 (see FIG. 9). The core 187 may be printed on the bottom surface of the magnetic sheet 186.

The protective layer 180 may be formed by printing the electrode pattern 182, the dielectric 185, and the magnetic sheet 186 on the upper surface of the second pattern layer 160 without using a separate dielectric sheet 181. . That is, when the dielectric layer (eg, LTCC) is printed on the upper surface of the second pattern layer 160, the protective layer 180 may include the electrode pattern 182, the dielectric 185, and the upper surface of the second pattern layer 160. The magnetic sheet 186 may be printed and formed.

As described above, the HDMI common mode filter 100 is formed by printing a dielectric sheet constituting the insulating layer on the electrode portion, thereby ensuring an insulating layer and minimizing the reduction of the effect of the magnetic material. have.

Incidentally, the common mode filter 100 for HDMI increases the common mode impedance, thereby minimizing and reducing the size of the common mode filter by minimizing the length of the pattern, and improving the high frequency characteristics.

In addition, the common mode filter 100 for HDMI is formed by printing a dielectric sheet constituting the insulating layer on the electrode portion, so that the firing temperature can be increased as compared to the conventional common mode filter, so that the common mode impedance and the differential mode SRF The impedance is increased and the magnetic permeability of the magnetic material is increased to increase the impedance of the common mode and the SRF impedance of the differential mode.

Hereinafter, the characteristics of the common mode filter for HDMI according to the first embodiment of the present invention will be described in detail with reference to the accompanying drawings.

10 is a view for explaining the characteristics of the common mode filter 100 for HDMI according to the first embodiment of the present invention.

The common mode filter 100 for HDMI may include a dielectric 125 formed between the magnetic sheets 126 and 186 and the electrode patterns 122 and 182 in order to minimize blockage of transmission of magnetic properties to the electrode patterns 122 and 182. , 185 is formed in the same manner as the electrode patterns 122 and 182. That is, by forming the dielectrics 125 and 185 having the same size as the electrode patterns 122 and 182 between the magnetic sheets 126 and 186 and the electrode patterns 122 and 182, the electrode sheets 122 and 182 are formed into the electrode patterns 122 and 182. It is characterized by minimizing the blocking of the transfer of magnetic properties. Of course, the dielectrics 125 and 185 formed between the magnetic sheets 126 and 186 and the electrode patterns 122 and 182 may be printed larger than the electrode patterns 122 and 182 within a setting range. Here, the setting range may be set differently according to the size and shape of the electrode patterns 122 and 182, and thus the setting range is not limited. For example, as shown in FIG. 10, when the electrode patterns 122 and 182 having a line width of about 50 μm are printed, the dielectrics 125 and 185 may be printed to have a line width of about 150 μm or less. Can be.

11 and 12 are diagrams for comparing and explaining the characteristics of the common mode filter for HDMI and the conventional common mode filter for HDMI according to the first embodiment of the present invention.

 In FIG. 11, curve A shows a change in common mode impedance of the common mode filter 100 for HDMI according to the first embodiment of the present invention, and curve B shows a conventional common mode filter 100 for HDMI using LTCC interleave. ) Shows the change in common mode impedance. Curve C shows the differential mode impedance change of the common mode filter 100 for HDMI according to the first embodiment of the present invention, curve D is a differential mode of the conventional common mode filter 100 for HDMI using LTCC interleaver The impedance change is shown.

As can be seen in FIG. 11, the base layer is printed between the magnetic sheets 126 and 186 and the electrode patterns 122 and 182 by printing the dielectrics 125 and 185 which are the same as or larger than the electrode patterns 122 and 182 or within a set range. As the 120 and the protective layer 180 are formed, the common mode impedance in the low frequency band of about 100 MHz is increased (raised) by 20% or more.

On the other hand, as shown in Figure 12, the common mode filter 100 for HDMI and the conventional common mode filter 100 for HDMI according to the first embodiment of the present invention in a low frequency band of about 100 MHz (Ω) It can be seen that the differential mode impedance has almost the same characteristics in the common mode SRF and the differential mode SRF. That is, the common mode filter 100 for HDMI according to the first embodiment of the present invention which partially prints the dielectrics 125 and 185 has the same effect as that formed on the magnetic body, and has the same insulation characteristics as those of the dielectrics. It means to have.

As described above, the partial mode printing common mode filter 100 for HDMI is a conventional common mode for HDMI, which is a dielectric sheet stacking method covering the entire surface of the magnetic sheet in the characteristics of differential mode impedance, common mode SRF, and differential mode SRF. While maintaining the same characteristics as the filter 100, it can be seen that there is an effect that the common mode impedance is increased by 20% or more compared with the conventional common mode filter 100 for HDMI.

13 and 14 are diagrams for explaining characteristics according to firing temperatures of the common mode filter 100 for HDMI according to the first embodiment of the present invention.

In general, the conventional common mode filter 100 for HDMI prints an electrode pattern made of silver (Ag) on a dielectric sheet (that is, LTCC interlayer) for low dielectric constant (that is, to improve common mode impedance characteristics). Was used. At this time, since a low reactivity dielectric material (for example, CaO-BaO-SiO ₂ , Tg: 700 ° C. or more) is used as the dielectric sheet, a problem arises in the bonding property with the magnetic sheet. Accordingly, the conventional common mode filter 100 for HDMI cannot be fired at a high temperature.

On the other hand, the common mode filter 100 for HDMI according to the first embodiment of the present invention partially prints the dielectrics 125 and 185 of the glass material between the magnetic sheets 126 and 186 and the electrode patterns 122 and 182. Use the method. When the dielectrics 125 and 185 are printed, there is no problem in bonding with the magnetic sheets 126 and 186. Accordingly, the common mode filter 100 for HDMI according to the first embodiment of the present invention can be fired at a high temperature, thereby increasing the magnetic permeability.

In Fig. 13, curve E shows the change in the common mode impedance of the common mode filter 100 for HDMI fired at about 890 ° C, and curve F shows the change in the common mode filter 100 for HDMI fired at about 830 ° C. Common mode impedance change is shown. Curve G shows the differential mode impedance change of the common mode filter 100 for HDMI fired at about 890 ° C., and curve H shows the differential mode impedance change of the common mode filter 100 for HDMI fired at about 830 ° C. It is shown.

As can be seen from Fig. 13, since the common mode filter 100 for HDMI is fired at a firing temperature of about 890 ° C, the firing temperature of the common mode impedance in the low frequency band of about 100 MHz is about 830 ° C. Is increased by more than 10% compared to the common mode filter 100 for HDMI.

Meanwhile, as shown in FIG. 14, the common mode filter 100 for the HDMI fired at about 890 ° C. has a common mode impedance and the differential mode SRF compared to the common mode filter 100 for the HDMI fired at about 830 ° C. It can be seen that the impedance increases (raises). That is, since the common mode filter 100 for HDMI according to the first embodiment of the present invention can be baked at a high temperature by partially printing a dielectric for insulating the magnetic material and the electrode pattern, the magnetic permeability of the magnetic material is increased to increase the common mode impedance. And the differential mode SRF impedance is increased.

15 is a view for explaining the cutoff frequency characteristics of the common mode filter for HDMI according to the first embodiment of the present invention. As shown in FIG. 15, the common mode filter 100 for HDMI according to the first embodiment of the present invention has a cutoff frequency at about 3.5 kHz. Through this, it can be seen that the HDMI common mode filter 100 according to the first embodiment of the present invention satisfies a cutoff frequency characteristic of 3 kHz or more that is required in the HDMI common mode filter 100 market. That is, the HDMI common mode filter 100 according to the first embodiment of the present invention may be miniaturized and slimmed, differential mode impedance characteristics, IR characteristics, cutoff frequency characteristics, and the like, which are required in the HDMI common mode filter 100 market. And improved common-mode impedance characteristics.

(Second Embodiment)

Hereinafter, the common mode filter for HDMI according to the second embodiment of the present invention will be described in detail with reference to the accompanying drawings. 16 is a diagram for explaining the structure of a common mode filter for HDMI according to a second embodiment of the present invention. FIG. 17 is a diagram for describing the base layer of FIG. 16, FIG. 18 is a diagram for explaining the first pattern layer of FIG. 16, and FIG. 19 is a diagram for explaining the second pattern layer of FIG. 16. 20 is a diagram for describing the protective layer of FIG. 16.

As illustrated in FIG. 16, the common mode filter 200 for HDMI includes a base layer 220, a first pattern layer 240, a second pattern layer 260, and a protective layer 280. Here, the common mode filter 200 for HDMI is divided into a base layer 220, a first pattern layer 240, a second pattern layer 260, and a protective layer 280 for convenience of description. The mode filter 200 is manufactured by stacking the components included in each layer. In particular, the dielectric layers 222 and 281 formed on the base layer 220 and the protective layer 280 to insulate the magnetic sheets 221 and 283 and the electrode patterns 223 and 282 may be formed of the electrode patterns 223 and 282. Characterized in that the same size and shape. Of course, the dielectrics 222 and 281 may be printed larger than the electrode patterns 223 and 282 within a setting range. Here, the setting range may be set differently according to the size and shape of the electrode patterns 223 and 282, and thus the range is not limited.

At this time, in the second embodiment of the present invention, the base layer 220, the first pattern layer 240, and the second pattern layer 260 are formed by laminating and printing a magnetic sheet, a dielectric, an electrode pattern, and a dielectric. do. That is, the dielectrics 222, 242, 262, and 281 are partially printed on the ferrite magnetic sheets 221, 241, 261, and 283 in the same size and shape as the electrode patterns 223,, 243, 263, and 282. The electrode patterns 223, 243, 263, and 282 are printed on the dielectrics 222, 242, 262, and 281. The via electrodes 226 and 266 are printed on the magnetic sheets 241 and 261, and the magnetic bodies 225, 245, 265 and 285 on the upper outer side and the core (center) of the magnetic sheets 221, 241, 261 and 283. ). On top of the magnetic sheets 221, 241, 261, 283 printed with dielectrics 222, 242, 262, 281, electrode patterns 223, 243, 263, 282 and magnetic bodies 225, 245, 265, 285. Printing the dielectrics 222, 242, 262, and 281 to generate a magnetic sheet (that is, a base layer 120, a first pattern layer 140, a second pattern layer 160, and a protective layer 180), The magnetic sheet is laminated to form a common mode filter 200 for HDMI.

The base layer 220 is located at the bottom. The base layer 220 is formed by printing a dielectric 222, an electrode pattern 223, a magnetic body 225, and a dielectric sheet 224 on an upper surface of a sheet 221 formed of a magnetic material (eg, ferrite). That is, as shown in FIG. 17, the magnetic sheet 221 is disposed at the bottom of the base layer 220. The dielectric 222 for insulating the magnetic sheet 221 and the electrode pattern 223 is printed on the upper surface of the magnetic sheet 221. In this case, the dielectric 222 is mainly glass, and is printed in the same size and shape as the electrode pattern 223 printed on the dielectric 222. Of course, the dielectric 222 formed between the magnetic sheet 221 and the electrode pattern 223 may be printed larger than the electrode pattern 223 within the setting range. Here, since the setting range may be set differently according to the size and shape of the electrode pattern 223, the range is not limited. The electrode pattern 223 is printed on the top surface of the dielectric 222. At this time, the lead electrode (not shown) exposed to the outside is formed at one end of the electrode pattern 223, and the electrode pattern 243 of the first pattern layer 240 is formed at the other end thereof, that is, the first pattern layer 240. A lead electrode (not shown) connected to the lead electrode (not shown) is formed. The magnetic body 225 is printed on the upper surface outer side and the core (center) of the magnetic body sheet 221. The dielectric sheet 224 having the via electrode 226 formed on the magnetic material 225 is printed.

The first pattern layer 240 is positioned on the base layer 220. The first pattern layer 240 is formed by printing a dielectric 242, an electrode pattern 243, a magnetic body 245, and a dielectric sheet 244 on an upper surface of a sheet 241 formed of a magnetic material (eg, ferrite). That is, as shown in FIG. 18, a magnetic sheet 241 (eg, a ferrite sheet) is disposed at the bottom of the first pattern layer 240. On the upper surface of the magnetic sheet 241, a dielectric 242 for insulating the magnetic sheet 241 and the electrode pattern 243 is printed. In this case, the dielectric 242 is mainly glass, and is printed in the same size and shape as the spiral-shaped electrode pattern 243 printed on the dielectric 242. Of course, the dielectric 242 formed between the magnetic sheet 241 and the electrode pattern 243 may be printed larger than the spiral electrode pattern 243 within the setting range. Here, the setting range may be set differently according to the size and shape of the spiral-shaped electrode pattern 243, and thus the range is not limited. The electrode pattern 243 is printed on the top surface of the dielectric 242. In this case, an extraction electrode (not shown) that is exposed to the outside is formed at one end of the electrode pattern 243, and an electrode pattern 223 of the base layer 220 is formed at the other end of the electrode pattern 243 (that is, the extraction electrode of the base layer 220). And an extraction electrode (not shown) connected thereto) is formed. The magnetic body 245 is printed on the upper surface outer side part and the core (center part) of the magnetic body sheet 241. The dielectric sheet 244 is printed on the magnetic material 245.

The second pattern layer 260 is positioned on the first pattern layer 240. The second pattern layer 260 is formed by printing a dielectric 262, an electrode pattern 263, a magnetic body 265, and a dielectric sheet 264 on an upper surface of a sheet 621 formed of a magnetic material (eg, ferrite). That is, as shown in FIG. 19, a magnetic sheet 261 (eg, a ferrite sheet) is disposed at the bottom of the second pattern layer 260. The dielectric 262 for insulating the magnetic sheet 261 and the electrode pattern 263 is printed on the top surface of the magnetic sheet 261. In this case, the dielectric 262 is mainly glass, and is printed in the same size and shape as the spiral electrode pattern 263 printed on the dielectric 262. Of course, the dielectric 262 formed between the magnetic sheet 261 and the electrode pattern 263 may be printed larger than the spiral electrode pattern 263 within a setting range. Here, the setting range may be set differently according to the size and shape of the spiral-shaped electrode pattern 263, and thus the range is not limited. The electrode pattern is printed on the upper surface of the dielectric. At this time, one end of the electrode pattern 263 is formed with a drawing electrode (not shown) that is exposed to the outside, the other end of the electrode pattern 282 of the protective layer 280 (that is, the drawing electrode of the protective layer 280) And an extraction electrode (not shown) connected thereto) is formed. The magnetic body 265 is printed on the upper surface outer side part and the core (center part) of the magnetic body sheet 261. The dielectric sheet 264 having the via electrode 266 formed on the magnetic material 265 is printed.

The protective layer 280 is positioned on the second pattern layer 260. The protective layer 280 is formed by printing a magnetic body 285, an electrode pattern 282, a dielectric 281, and a magnetic sheet 283 on the upper surface of the second pattern layer 260. That is, as shown in FIG. 20, the magnetic layer 285 is printed on the upper surface core (center) of the second pattern layer 260. The electrode pattern 282 is printed on the upper surface of the second pattern layer 260 by being spaced apart from the magnetic body 285 by a predetermined distance. At this time, the lead electrode (not shown) exposed to the outside is formed at one end of the electrode pattern 282, the electrode pattern 263 of the second pattern layer 260 (that is, the second pattern layer 260) at the other end A lead electrode (not shown) connected to the lead electrode (not shown) is formed.

The dielectric 281 is printed on the upper surface of the electrode pattern 282. In this case, the dielectric material 281 is mainly glass, and is printed in the same size and shape as the electrode pattern 282. Of course, the dielectric 281 formed between the magnetic sheet 283 and the electrode pattern 282 may be printed larger than the electrode pattern 282 within the setting range. Here, since the setting range may be set differently according to the size and shape of the electrode pattern 282, the setting range is not limited. The magnetic sheet 283 is printed on the upper surface of the dielectric 281 so as to cover the electrode pattern 282 and the dielectric 281.

The common mode filter 200 for HDMI according to the second embodiment of the present invention is formed so as to be affected at the upper, lower, left, right, and center portions of the electrode pattern by printing the magnetic material on the upper outer side and the core of the magnetic sheet. Compared to the conventional magnetic body effect is provided only in the upper and lower direction of the electrode pattern, the common mode impedance is increased, and the punching and casting process is omitted, thereby reducing the equipment investment cost.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but many variations and modifications may be made without departing from the scope of the present invention. It will be understood that the invention may be practiced.

100: common mode filter for HDMI 120: base layer
121: dielectric sheet 122: electrode pattern
123 and 124: lead-out electrode 125: dielectric
126: magnetic sheet 127: core
140: first pattern layer 141: dielectric sheet
142: electrode patterns 144, 146: lead-out electrode
147: core 160: second pattern layer
161: dielectric sheet 162: electrode pattern
164 and 166: lead-out electrode 167: core
180: protective layer 181: dielectric
182: electrode patterns 183, 184: lead-out electrode
185 dielectric sheet 186 magnetic sheet
187: core
200: common mode filter for HDMI 220: base layer
221: magnetic sheet 222: dielectric
223: electrode pattern 224: dielectric sheet
225: magnetic material 226: via electrode
240: first pattern layer 241: magnetic sheet
242: dielectric 243: electrode pattern
244: dielectric sheet 245: magnetic material
260: second pattern layer 261: magnetic sheet
262: dielectric 263: electrode pattern
264: dielectric sheet 265: magnetic material
266: via electrode 280: protective layer
281 Dielectric 282 Electrode Pattern
283: magnetic sheet 285: magnetic sheet

Claims (18)

Magnetic sheet;
An electrode pattern printed on the upper surface of the magnetic sheet; And
It includes a base layer made of a dielectric printed between the magnetic sheet and the electrode pattern,
And the dielectric is formed only at a portion where the electrode pattern is formed on an upper surface of the magnetic sheet. The method according to claim 1,
And a first pattern layer formed by printing an electrode pattern on the dielectric sheet and stacked on the base layer. The method according to claim 2,
And a second pattern layer formed by printing an electrode pattern on the dielectric sheet and stacked on the first pattern layer. The method according to claim 3,
Dielectric sheets;
An electrode pattern printed and formed on an upper surface of the dielectric sheet;
A dielectric formed on the upper surface of the electrode pattern; And
A protective layer composed of a magnetic sheet printed and formed on top of the dielectric layer and stacked on the second pattern layer,
And the dielectric is printed and formed only on a portion of the magnetic sheet on which the electrode pattern is formed. The method according to claim 1,
A dielectric sheet printed and formed on the electrode pattern of the base layer; And
And a first pattern layer formed of an electrode pattern printed and formed on the dielectric sheet. The method according to claim 5,
A dielectric sheet printed and formed on the electrode pattern of the first pattern layer; And
And a second pattern layer formed of an electrode pattern printed and formed on the dielectric sheet. The method of claim 6,
A dielectric sheet printed and formed on the electrode pattern of the second pattern layer;
An electrode pattern printed and formed on an upper surface of the dielectric sheet;
A dielectric formed on the upper surface of the electrode pattern; And
It includes a protective layer consisting of a magnetic sheet is formed printed on top of the dielectric,
And the dielectric is printed and formed only on a portion of the magnetic sheet on which the electrode pattern is formed. The method according to any one of claims 1, 4, and 7,
And the dielectric is formed in the same size and shape as the electrode pattern. The method according to any one of claims 1, 4, and 7,
And the dielectric is formed to be larger than a predetermined range than the electrode pattern. Magnetic sheet;
A dielectric formed by printing on the upper surface of the magnetic sheet;
An electrode pattern printed and formed on an upper surface of the dielectric; And
Including a base layer consisting of a dielectric sheet is formed printed on the electrode pattern,
The magnetic sheet is spaced apart from the electrode pattern on the outer surface and the central portion of the upper surface, a magnetic material is formed,
And the dielectric is formed only at a portion where the electrode pattern is formed. The method according to claim 10,
Magnetic sheet;
A dielectric formed on top of the magnetic sheet;
An electrode pattern printed and formed on the dielectric; And
Further comprising a first pattern layer consisting of a dielectric sheet printed on the upper portion of the electrode pattern is laminated on the protective layer,
The magnetic sheet is spaced apart from the electrode pattern on the outer surface and the central portion of the upper surface, a magnetic material is formed,
And the dielectric is formed only at a portion where the electrode pattern is formed. The method of claim 11,
Magnetic sheet;
A dielectric formed on top of the magnetic sheet;
An electrode pattern printed and formed on the dielectric; And
Further comprising a second pattern layer composed of a dielectric sheet printed on the upper portion of the electrode pattern is laminated on the first pattern layer,
The magnetic sheet is spaced apart from the electrode pattern on the outer surface and the central portion of the upper surface, a magnetic material is formed,
And the dielectric is formed only at a portion where the electrode pattern is formed. The method of claim 12,
Electrode patterns;
A dielectric printed on the electrode pattern;
Further comprising a protective layer composed of a magnetic sheet is formed printed on the upper portion of the dielectric stacked on top of the second pattern layer,
The magnetic body is formed on the outer side and the center of the lower surface of the magnetic sheet to be spaced apart from the electrode pattern,
And the dielectric is printed and formed only on a portion where the electrode pattern is formed. The method according to claim 10,
A magnetic sheet printed and formed on the dielectric sheet of the base layer;
A dielectric formed on top of the magnetic sheet;
An electrode pattern printed and formed on the dielectric; And
Further comprising a first pattern layer consisting of a dielectric sheet is formed printed on the electrode pattern,
The magnetic sheet is spaced apart from the electrode pattern on the outer surface and the central portion of the upper surface, a magnetic material is formed,
And the dielectric is formed only at a portion where the electrode pattern is formed. The method according to claim 14,
A magnetic sheet printed and formed on the dielectric sheet of the first pattern layer;
A dielectric formed on top of the magnetic sheet;
An electrode pattern printed and formed on the dielectric; And
Further comprising a second pattern layer made of a dielectric sheet is formed printed on the electrode pattern,
The magnetic sheet is spaced apart from the electrode pattern on the outer surface and the central portion of the upper surface, a magnetic material is formed,
And the dielectric is formed only at a portion where the electrode pattern is formed. The method according to claim 15,
An electrode pattern printed on the dielectric sheet of the second pattern layer;
A dielectric printed on the electrode pattern; And
Further comprising a protective layer consisting of a magnetic sheet is formed printed on the top of the dielectric,
The magnetic body is formed on the outer side and the center of the lower surface of the magnetic sheet to be spaced apart from the electrode pattern,
And the dielectric is formed only at a portion where the electrode pattern is formed. The method according to any one of claims 13 to 16,
And the dielectric is formed in the same size and shape as the electrode pattern. The method according to any one of claims 13 to 16,
And the dielectric is formed to be larger than a predetermined range than the electrode pattern.

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