JP2010135602A - Noise suppressing component and connection structure of the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a noise suppressing component which not only functions as a common mode choke coil, but also suppresses the occurrence of radiant noise by adjusting a voltage balance on a substrate side and a voltage balance on a connector side, and to provide a connection structure of the same. <P>SOLUTION: The noise suppressing component 1 includes a common mode choke coil part 3-1, a common mode choke coil part 3-2, a laminate 2 including them, external terminals 4-1, 4-3, 4-5 arranged on a front surface 2a of the laminate 2 side by side, and external terminals 4-2, 4-4, 4-6 arranged on a rear surface 2b side by side. Coils 31, 32 face each other. Coils 33, 34 face each other in an adjacent state to the coils 31, 32. A parallel circuit of the coils 31, 34 is formed. The external terminals 4-1, 4-2 are connected to both ends of the parallel circuit, the external terminals 4-3, 4-4 are connected to both ends of the coil 32, and the external terminals 4-5, 4-6 are connected to both ends of the coil 33. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a noise countermeasure component for removing noise on a differential transmission path and a connection structure thereof.

Usually, a connector for connecting a differential transmission cable to an electronic circuit component on the board is provided on a board having electronic circuit parts for transmitting and receiving differential signals, and a pair of coils for removing noise. Is provided between the electronic circuit components of this connector (see, for example, Patent Document 1).
Specifically, a pair of coils are formed on the surface of a substrate having a solid ground layer, a pair of differential signal pins of the connector are connected to these coils, and the ground pins are connected to the ground layer. It is connected.
This connects the cable that passes one differential signal to one differential signal pin of the connector, and connects the cable that passes the other differential signal to the other differential signal pin of the connector. By connecting the grounding cable to the ground pin, the differential signal is transmitted / received to / from the electronic circuit component, and the generated noise is removed by a pair of coils.
However, in such a configuration, since the pair of coils are formed on the surface of the substrate having the solid ground layer, the function as the common mode choke coil cannot be sufficiently exhibited, and the noise removal effect is low.

Therefore, it is also considered to improve the noise countermeasure effect by providing a common mode choke coil array (for example, see Patent Document 2) having four coils and eight external terminals between the connector and the electronic circuit component. Can do.
FIG. 14 is a circuit diagram showing a noise countermeasure structure using a common mode choke coil array.
In FIG. 14, reference numeral 100 denotes a differential transmission cable, reference numeral 110 denotes a connector attached to a substrate (not shown), and reference numeral 120 denotes a common mode choke coil array provided between the connector and the electronic circuit component. .
As shown in FIG. 14, the positive differential signal line 101 and the negative differential signal line 102 of the differential transmission cable 100 are connected to the adjacent differential signal pins 111 and 112 of the connector 110, and the ground line 103 is It is connected to the ground pin 113 of the connector 110.
In this state, the ground pin 113 is directly connected to the ground layer 130 of the substrate.
The common mode choke coil array 120 includes four coils 121 to 124 and eight external terminals 125 to 132, and the coil 122 is connected to the differential signal pin 111 of the connector 110 through the external terminal 126, and the coil 123. Is connected to the differential signal pin 112 of the connector 110 through the external terminal 127. The coils 121 and 124 are connected to the ground layer 130 through the external terminals 125, 128, 129, and 131.
With this structure, common mode noise that has entered the common mode choke coil array 120 through the external terminals 125 and 126 (or 127 and 128) is removed by the choke coil portions of the coils 121 and 122 (or the coils 123 and 124). I am doing so.

Japanese Patent Laid-Open No. 10-242892 JP 2003-217932 A

  In the technique shown in FIG. 14, the reference voltage of the coils 122 and 123 on the substrate side in the differential mode is located between the voltage of the coil 122 and the voltage of the coil 123. On the other hand, on the connector 110 side, the ground pin 113 is directly connected to the ground layer 130 of the substrate, and the ground pin 113 is located outside the differential signal pins 111 and 112. Therefore, the reference voltage of the differential signal pins 111 and 112 is not located between the voltage of the differential signal pin 111 and the voltage of the differential signal pin 112. As a result, the voltage balance on the board side and the voltage balance on the connector 110 side are greatly different, and the differential mode may be converted to the common mode, and radiation noise may be generated.

  The present invention has been made to solve the above-described problems, and not only functions as a common mode choke coil, but also generates radiation noise by adjusting the voltage balance on the board side and the voltage balance on the connector side. An object of the present invention is to provide a noise suppression component that can be suppressed and a connection structure thereof.

In order to solve the above-mentioned problems, the invention of claim 1 includes a first coil and a second coil constituting the first common mode choke coil section, and a second adjacent to the first common mode choke coil section. A noise countermeasure component comprising a third coil and a fourth coil constituting the common mode choke coil portion, wherein the first external terminal and the second external terminal for connecting to the ground line are A pair of differential signal lines are respectively connected to both ends of a parallel circuit formed by connecting the first coil of the common mode choke coil section and the fourth coil of the second common mode choke coil section in parallel. A third external terminal and a fourth external terminal for connecting to one of the two are connected to both ends of the second coil, respectively, and a fifth external terminal for connecting to the other of the pair of differential signal lines And the sixth outer end And a structure connected to both ends of the third coil.
With this configuration, the first external terminal and the second external terminal of the noise countermeasure component are connected to the ground line that is drawn from the ground pin of the connector on the board and reaches the ground layer, and the third external terminal and the fourth external terminal are connected. Are connected to one of the pair of differential signal lines drawn from the pair of differential signal pins, and the fifth and sixth external terminals are connected to the pair of differential signal pins. Can be connected to the other of the pair of differential signal lines drawn out from.
In this state, when one differential signal is sent from one differential signal pin of the connector to one differential signal line, the differential signal is transmitted to the third external terminal and fourth external terminal of the noise countermeasure component. The signal is output from the terminal to the one differential signal line through the second coil. Further, when the other differential signal is sent from the other differential signal pin of the connector to the other differential signal line, the differential signal is sent from the fifth external terminal and the sixth external terminal of the noise countermeasure component. The signal is output on the other differential signal line through the third coil.
Then, by connecting the first external terminal and the second external terminal respectively connected to both ends of the parallel circuit of the first coil and the fourth coil on the ground line, noise countermeasures can be achieved in the differential mode. Both the reference voltage of the voltage of the second and third coils of the component and the reference voltage of the pair of differential signal pins of the connector can be set to the potential on the ground line. As a result, the voltage balance between the differential signal pins on the connector side and the voltage balance between the second and third coils on the board side can be made substantially equal.
When common mode noise enters one differential signal line and the ground line of the pair of differential signal lines (or the other differential signal line and the ground line), the first common mode choke coil Section (or the second common mode choke coil section) functions to remove this common mode noise.

  According to a second aspect of the present invention, in the noise countermeasure component according to the first aspect, the first coil and the second coil of the first common mode choke coil portion are laminated in the laminated body so as to face each other. The two common mode choke coil portions are included in the laminate so as to be adjacent to the first common mode choke coil portion, and the third coil and the fourth coil of the second common mode choke coil portion are laminated. The first external terminal, the third external terminal, and the fifth external terminal are juxtaposed on one outer surface of the multilayer body, and the second external terminal and the fourth external terminal are formed so as to face each other. The external terminal and the sixth external terminal are arranged side by side on the other outer surface facing the one outer surface.

According to a third aspect of the present invention, there is provided a noise countermeasure component connecting structure including a pair of differential signal lines and a ground line, and a pair of differential signal pins and ground pins included in a connector on the board. A pattern is formed on the substrate so as to extend to the ground layer of the substrate, and the first external terminal and the second external terminal in the noise countermeasure component of claim 1 or 2 are connected to the ground line of the substrate. The third external terminal and the fourth external terminal are connected to one of the pair of differential signal lines, and the fifth external terminal and the sixth external terminal are connected to the other of the pair of differential signal lines. The configuration is connected to
With this configuration, when a cable is connected to a connector on the board and a pair of differential signals is transmitted, one differential signal reaches one differential signal line from one differential signal pin of the connector, and noise The signal is output from the third external terminal and the fourth external terminal of the countermeasure component to the one differential signal line through the second coil. The other differential signal reaches from the other differential signal pin of the connector to the other differential signal line, and passes through the third coil from the fifth external terminal and the sixth external terminal of the noise countermeasure component. It is output on the other differential signal line. As a result, a pair of differential signals is sent to the electronic circuit component through the pair of differential signal lines.
In the differential mode, in the mounted noise countermeasure component, the first external terminal and the second external terminal respectively connected to both ends of the parallel circuit of the first coil and the fourth coil are connected to the connector ground. It is connected to a ground line that is drawn from the pin and reaches the ground layer. For this reason, both the reference voltage of the voltage of the second and third coils of the noise countermeasure component and the reference voltage of the pair of differential signal pins of the connector become the potential on the ground line, and between the differential signal pins on the connector side The voltage balance and the voltage balance between the second and third coils on the substrate side are substantially equal.
When common mode noise enters one differential signal line and the ground line of the pair of differential signal lines (or the other differential signal line and the ground line), the first common mode choke coil Section (or the second common mode choke coil section) functions to remove this common mode noise.

  As described above in detail, according to the noise countermeasure component and the connection structure thereof of the present invention, not only common mode noise can be removed, but also the voltage balance on the connector side and the voltage balance on the board side can be made substantially equal. Therefore, there is an excellent effect that the generation of radiation noise caused by the difference in voltage balance can be suppressed.

  The best mode of the present invention will be described below with reference to the drawings.

  1 is an exploded perspective view showing a noise countermeasure component according to a first embodiment of the present invention, FIG. 2 is an external view of the noise countermeasure component shown in FIG. 1, and FIG. 3 is a noise countermeasure component of FIG. It is a perspective view which sees through and shows the inside of components.

  As shown in FIGS. 1 to 3, the noise countermeasure component 1 of this embodiment is a stacked common mode choke coil array, and includes a common mode choke coil section 3-1 as a first common mode choke coil section. The common mode choke coil section 3-2 as the second common mode choke coil section is included in the laminate 2 so as to be adjacent to each other, and the six external terminals 4 as the first to sixth external terminals are included. -1 to external terminals 4-6 are attached to the outer surface of the laminate 2.

The common mode choke coil section 3-1 includes a coil 31 as a first coil and a coil 32 as a second coil.
Specifically, as shown in FIG. 1, the spiral coil 31 is patterned on the insulating layer 22 stacked on the magnetic substrate 21, and the insulating layers 22 to 25 are stacked on the coil 31. A coil 32 having substantially the same shape as the coil 31 is patterned on the insulating layer 25 and at a position directly above the coil 31. Thereby, the coil 31 and the coil 32 are positioned so as to face each other in the stacked body 2.

On the other hand, the common mode choke coil section 3-2 includes a coil 33 as a third coil and a coil 34 as a fourth coil.
Specifically, a spiral coil 33 symmetric about the coil 32 and the center line M is patterned on the insulating layer 25, and a coil 34 having substantially the same shape as the coil 33 is on the insulating layer 22 and A pattern is formed at a position directly below the coil 33. Accordingly, the coil 33 and the coil 34 are positioned so as to face each other in a state where they are adjacent to the coil 31 and the coil 32.

Further, the coil 31 of the common mode choke coil section 3-1 and the coil 34 of the common mode choke coil section 3-2 are connected in parallel, and a parallel circuit of the coils 31, 34 is formed on the insulating layer 22. .
Specifically, the outer ends of the coils 31 and 34 are connected to each other by a linear pattern 35b formed on the front edge (the front edge in FIGS. 1 to 3) on the insulating layer 22. Lead-out patterns 35c and 35d are formed on the insulating layer 23, and the bases thereof are connected to the inner ends of the coils 31 and 34 through the through holes 23a and 23b of the insulating layer 23, respectively. The lead patterns 35c and 35d are connected to each other by a linear pattern 35e formed on the rear edge (the edge on the back side in FIGS. 1 to 3) on the insulating layer 22. Furthermore, the connection end portion 35a extends from the left portion of the linear pattern 35b and is exposed on the front outer surface (the outer surface on the front side in FIGS. 1 to 3) of the stacked body 2, and the connection end portion 35f is linear. It extends from the left part of the pattern 35e and is exposed on the rear outer surface of the laminate 2 (the outer surface on the back side in FIGS. 1 to 3).

  In the coils 32 and 33, lead-out patterns 36 b and 37 b are formed on the insulating layer 25, and these connection end portions 36 a and 37 a are formed at the center portion and the right portion of the front edge on the insulating layer 25, respectively. It is exposed on the front outer surface of the laminate 2. In addition, lead patterns 36c and 37c are formed on the insulating layer 26, and base portions thereof are connected to inner end portions of the coils 32 and 33 through through holes 26a and 26b of the insulating layer 26, respectively. Then, connection end portions 36d and 37d of the lead patterns 36c and 37c are respectively formed at the center portion and the right portion of the upper rear edge of the insulating layer 26, and are exposed from the rear outer surface of the stacked body 2.

  The magnetic substrate 29 is disposed on the coils 32 and 33, and is adhered to the insulating layer 26 by the adhesive layers 27 and 28 so as to cover the lead patterns 36c and 37c.

The external terminals 4-1 to 4-6 are provided on the outer surface of the multilayer body 2 including the common mode choke coil portions 3-1 and 3-2 as described above. This will be specifically described below.
FIG. 4 is a plan view showing a connection state between the parallel circuit of the coils 31 and 34 and the external terminals 4-1 and 4-2, and FIG. It is a top view which shows a connection state with -6.

As shown in FIGS. 4A and 4B, the coils 31 and 34 on the insulating layer 22 are connected to the lead patterns 35c and 35d on the insulating layer 23 through the through holes 23a and 23b. (C), a parallel circuit of the coils 31 and 34 is configured.
The external terminals 4-1 and 4-2 are terminals for connection to a ground line to be described later. As shown in FIGS. 2 and 3, the external terminal 4-1 is one outer surface of the multilayer body 2. The external terminal 4-2 is disposed on the left side of the rear surface 2b, which is the other outer surface facing the front surface 2a of the multilayer body 2.
As shown in FIG. 4C, the external terminal 4-1 is connected to the connection end 35a of the parallel circuit, and the external terminal 4-2 is connected to the connection end 35f of the parallel circuit. .

  Further, as shown in FIGS. 5A and 5B, by connecting the coils 32 and 33 on the insulating layer 25 and the lead patterns 36c and 37c on the insulating layer 26 through the through holes 26a and 26b, As shown in FIG. 5 (c), coils 32 and 33 are formed in which the connection end portions 36a and 37a are exposed on the front surface 2a of the laminate 2 and the connection end portions 36d and 37d are exposed on the rear surface 2b. The

The external terminals 4-3 and 4-4 are terminals for connecting to one differential signal line described later. As shown in FIGS. 2 and 3, the external terminals 4-3 are connected to the laminate 2. The external terminal 4-4 is disposed at the center of the rear surface 2 b of the laminate 2.
As shown in FIG. 5C, the external terminals 4-3 and 4-4 are connected to the connection ends 36a and 36d of the coil 32, respectively.

The external terminals 4-5 and 4-6 are terminals for connecting to the other differential signal line described later. As shown in FIGS. The external terminal 4-6 is disposed on the right side of the rear surface 2 b of the laminate 2.
Then, as shown in FIG. 5C, the external terminals 4-5 and 4-6 are connected to the connection end portions 37a and 37d of the coil 33, respectively.

  As described above, the external terminal 4-1, the external terminal 4-3, and the external terminal 4-5 are arranged in parallel on the front surface 2a of the multilayer body 2, and the external terminal 4-2, the external terminal 4-4, and the external terminal are arranged. 4-6 are juxtaposed on the rear surface 2b so as to face the external terminals 4-1, 4-3, 4-5, and further, as shown in FIG. 2, these external terminals 4-1, 4 The pitch d1 of −3, 4-5 (4-2, 4-4, 4-6) is a distance d2 between a ground line 143, one differential signal line 141, and the other differential signal line 142, which will be described later. It is set almost equal.

Here, an example of a manufacturing method of the noise countermeasure component 1 will be briefly described.
6 is a process diagram showing a method for manufacturing the noise countermeasure component 1, FIG. 7 is a cross-sectional view showing a lamination process, FIG. 8 is a cross-sectional view showing a crimping process, and FIG. 9 is a dicing process. It is the schematic which shows a baking process and an external terminal formation process.
As shown in FIG. 6, the noise countermeasure component 1 is manufactured by executing a stacking step S1, a crimping step S2, a dicing step S3, a firing step S4, and an external terminal forming step S5.

First, in the lamination step S1, a magnetic substrate 21 such as ferrite is prepared.
In this embodiment, the insulating layers 22 to 26 are stacked on the magnetic substrate 21, but depending on the application, the insulating layer may be stacked on the substrate formed of a dielectric or an insulator. good. However, the substrate 21 is polished so that the surface roughness Ra is 0.5 μm or less so that there is no problem when the insulating layers 22 to 26 and the coils 31 to 34 that are conductor patterns are stacked on the substrate 21. It is desirable to keep it.
On the substrate 21, the insulating layers 22 to 26 and the coils 31 to 34, which are conductor patterns, are alternately stacked a plurality of times using a photolithography technique.
Specifically, as shown in FIG. 7A, an insulating layer 22 made of polyimide resin is laminated on the upper surface of the magnetic substrate 21, and then sputtering, vapor deposition, or the like is performed as shown in FIG. 7B. The Ag film layer is formed on the insulating layer 22 by using a film forming technique such as a thin film forming method or a thick film forming method such as screen printing, and thereafter, a series of processes such as resist coating, exposure, development and etching are performed. Using the photolithography technique, the conductor patterns of the coils 31, 34, the connecting end portion 35a, and the linear pattern 35b (see FIG. 1) are formed.
Subsequently, as shown in FIG. 7C, a photosensitive polyimide resin is applied on these conductor patterns 31, 34, 35a, and 35b, and exposure and development are performed, thereby providing through holes 23a and 23b. The insulating layer 23 thus formed is formed. On the insulating layer 23, the lead patterns 35c and 35d, the linear pattern 35e, the conductor pattern of the connecting end portion 35f (see FIG. 1) and the insulating layer 24 are sequentially laminated, so that the coils 31 and 34 A parallel circuit is formed.
Thereafter, adjacent coils 32 and 33 are formed on the insulating layer 24 by alternately laminating the insulating layers 25 and 26, the coils 32 and 33 as the conductor patterns, and the lead patterns 36c and 37c. To do.
Thereby, lamination process S1 is completed.
In this example, Ag is used as a material for forming conductor patterns such as coils 31 to 34, connection end portions 35a, 35b to 37a and 37b, linear patterns 35b and 35e, and lead patterns 35c, 35d, 36b and 37b. However, as a matter of course, a metal such as Cu, Pd, or Al having excellent conductivity or an alloy thereof can be used as these conductor patterns.
In addition, although polyimide resin is used as the insulating layers 22 to 26, in order to form the through holes 23a, 23b, 26a, and 26b in the insulating layers 23 and 26, the insulating layers 22 to 26 are made of photosensitive polyimide resin. It is necessary to use it. In addition to the polyimide resin, the insulating layers 22 to 26 can be made of various resin materials such as epoxy resin and benzocycloptene resin, glass such as SiO2, glass ceramics, dielectrics and the like.

Next, in the crimping step S2, first, as shown in FIG. 8A, a magnetic substrate 29 similar to the magnetic substrate 21 is prepared, and a thermosetting polyimide resin that also functions as an insulating layer is prepared. The adhesive layers 27 and 28 are applied to the upper surface of the insulating layer 26 and the lead patterns 36 c and 37 c and the lower surface of the magnetic substrate 29, respectively, and the magnetic substrate 29 is bonded to the insulating layer 26.
In this state, as shown in FIG. 8 (b), the laminate 2 with the magnetic substrate 29 attached thereto is set in a vacuum hot press machine 200 and heated in vacuum or in an inert gas. By pressing the magnetic substrate 29 at a high pressure, the magnetic substrate 29 is thermocompression bonded onto the insulating layer 26 on which the drawing patterns 36c and 37c are formed. Thereafter, cooling and releasing the pressure of the vacuum hot press machine 200 completes the crimping step S3.
Note that when the noise countermeasure component 1 is reflow-mounted, the maximum temperature reaches about 260 ° C., and therefore a thermosetting polyimide resin having a glass transition temperature of 270 ° C. or higher is used as the adhesive layers 27 and 28. It was. Further, in the pressure bonding step S3, since the magnetic substrate 29 is pressure bonded by applying a high temperature of 350 ° C. to 390 ° C., the gas flows out from the adhesive layers 27 and 28 due to this high temperature and enters the adhesive layers 27 and 28. There is a risk of creating holes. This hole may cause a short circuit of the internal conductor pattern when the adhesion is reduced or moisture accumulates in the hole. Therefore, as the adhesive layers 27 and 28, it is desirable to use a thermosetting polyimide resin having a heat resistant temperature of 400 ° C. or higher.

As described above, the mother substrate 1 ′ having the laminate 2 is formed through the crimping step S3. Therefore, the mother substrate 1 ′ is divided into small chips by the dicing step S4.
Specifically, as shown in FIG. 9A, the mother substrate 1 ′ is divided by a dicing saw 300, and the chip 1 ″ is cut out as shown in FIG. 9B.
Thereafter, by chamfering with a barrel (not shown), it is possible to obtain the chip 1 ″ in which the connection end portions 35a, 35f, 36a, 37a, 36d, and 37d are exposed on the front surface 2a and the rear surface 2b of the laminate 2, respectively. it can.
And this chip | tip 1 '' is baked in baking process S4 as shown in (c) of FIG.
After the firing step S4, the external terminal forming step S5 is executed.

In the external terminal forming step S5, first, an Ag film is connected to the connection end portions 35a, 35f, 36a, 37a, 36d, and 37d by applying a conductive paste containing Ag, sputtering or vapor deposition of Ag, or the like. Is formed on the front surface 2a and the rear surface 2b of the laminate 2. Then, a metal film such as Ni, Sn, Sn—Pb is formed on the Ag film by wet electrolytic plating or the like.
Thereby, as shown in FIG.9 (d), the noise countermeasure component 1 provided with the external terminals 4-1 to 4-6 is manufactured.
In this example, the Ni film is provided on the thin film Ag to form the external terminals 4-1 to 4-6. However, the Ni film is formed on the thin film such as Ab-Pd, Cu, NiCr, or NiCu. , Sn, Sn-Pb, etc. may be provided to form the external terminals 4-1 to 4-6.

By adopting the above configuration, the noise countermeasure component 1 of this embodiment connects the external terminals 4-1 and 4-2 to, for example, a ground line that is drawn from the ground pin of the connector and reaches the ground layer of the board. The external terminals 4-3 and 4-4 are connected to one of the pair of differential signal lines drawn from the pair of differential signal pins, and the external terminals 4-5 and 4-6 are connected to one pair. Can be connected to the other of the differential signal lines.
In such a state, when a differential signal is transmitted through a cable connected to the connector on the board, one differential signal reaches one differential signal line from one differential signal pin of the connector. The signal is output from the external terminals 4-3 and 4-4 to one differential signal line through the coil 32. Further, the other differential signal reaches the other differential signal line from the other differential signal pin of the connector, passes through the coil 33 from the external terminals 4-5 and 4-6 of the noise countermeasure component, and the difference between the other differential signals. It is output on the motion signal line.

Next explained is the second embodiment of the invention.
FIG. 10 is a schematic perspective view for explaining the connection structure of the noise countermeasure component according to the second embodiment of the present invention, and FIG. 11 is a circuit diagram showing the connection structure of the noise countermeasure component.
In this embodiment, the noise countermeasure component connection structure for effectively removing noise on the substrate 150 using the noise countermeasure component 1 of the first embodiment (hereinafter simply referred to as “noise countermeasure structure”). It is an example.

  In FIG. 10, reference numeral 150 denotes a substrate having a connector 110 and an electronic circuit component 140 on the surface, and a solid ground layer 130 is formed on the back surface of the substrate 150.

  The connector 110 is a female connector for connecting the male connector 110 ′ of the differential transmission cable 100, and a pair of differential signal pins 111, 112 that receive the pins 111 ′, 112 ′, 113 ′ of the male connector 110 ′. And a ground pin 113.

A pair of differential signal lines 141 and 142 and a ground line 143 are formed between the connector 110 and the electronic circuit component 140 as a pattern.
Specifically, the positive differential signal line 141 extends from the differential signal pin 111 to the electronic circuit component 140, and the negative differential signal line 142 extends from the differential signal pin 112 to the electronic circuit component 140. ing. A ground line 143 extends from the ground pin 113 and is connected to the ground layer 130 on the back surface of the substrate 150 through a path (not shown).

The noise countermeasure component 1 is mounted on the differential signal lines 141 and 142 and the ground line 143.
Specifically, the lands 141a and 141b and the lands 142a and 142b are provided in the middle of the differential signal lines 141 and 142, respectively, and the lands 143a and 143b are provided in the middle of the ground line 143.
The external terminals 4-1 and 4-2 of the noise countermeasure component 1 are connected to the lands 143a and 143b of the ground line 143, and the external terminals 4-3 and 4-4 are connected to the lands 141a and 14b of the differential signal line 141. The external terminals 4-5 and 4-6 are soldered to the lands 142a and 142b of the differential signal line 142.

  The noise countermeasure structure of this embodiment adopts such a structure, and by connecting the male connector 110 ′ of the differential transmission cable 100 to the connector 110, as shown in FIG. The differential signal lines 101 and 102 are electrically connected to the electronic circuit component 140 through the connector 110, the differential signal lines 141 and 142, and the noise countermeasure component 1, and the ground line 103 is connected to the connector 110, the ground line 143, and noise. It is electrically connected to the ground layer 130 through the countermeasure component 1.

In this state, when the pair of positive and negative differential signal lines S + and S− is transmitted to the differential transmission cable 100, the differential signal lines S + and S− are connected to the differential signal on the substrate 150 through the connector 110. Output to lines 141 and 142. Then, the differential signal lines S + and S− reach the coils 32 and 33 from the external terminals 4-4 and 4-6 of the noise countermeasure component 1 and pass through the external terminals 4-3 and 4-5 to be electronic circuit components. The differential signal lines 141 and 142 on the 140 side are output to the electronic circuit component 140.
At this time, the ground line 103 of the differential transmission cable 100 passes through the ground pins 113 ′ and 113, the ground line 143 on the board 150, and the parallel circuit of the coils 31 and 34 of the noise countermeasure component 1. It is connected to the. That is, the ground pin 113 of the connector 110 is not directly connected to the ground layer 130 but is connected to the ground layer 130 through a parallel circuit of the coils 31 and 34. Therefore, in the differential mode as described above, the reference voltage of the coils 32 and 33 of the noise countermeasure component 1 and the reference voltage of the differential signal pins 111 and 112 of the connector 110 are both at the potential of the ground line 143. The voltage balance between the differential signal pins 111 and 112 on the connector 110 side and the voltage balance between the coils 32 and 33 on the board 150 side are substantially equal. As a result, the generation of radiation noise due to the difference in voltage balance can be suppressed.

  Further, when the common mode noise enters the differential signal line 141 and the ground line 143 (or the differential signal line 142 and the ground line 143), for example, the common mode choke coil unit 3-1 (or The common mode choke coil section 3-2) functions to remove this common mode noise.

The inventor conducted the following experiment in order to confirm the noise countermeasure effect.
FIG. 12 is a diagram showing the noise radiation characteristic in the differential mode and the noise radiation characteristic in the common mode when the conventional noise countermeasure structure is used, and FIG. 13 uses the noise countermeasure structure of this embodiment. FIG. 6 is a diagram showing noise radiation characteristics in a differential mode and noise radiation characteristics in a common mode when the operation is performed.
First, in the structure shown in FIG. 11, without providing the noise countermeasure component 1 and the conventional common mode choke coil array 120 shown in FIG. 14, the common mode noise radiation characteristic (Ssc12: dB) is set to a frequency of 30 MHz to 1000 MHz. When measured in the range, the dashed curve F1 of FIGS. 12 and 13 was obtained. Further, under the same structure, the noise radiation characteristic (Ssd12: dB) of the differential mode was measured in the frequency range of 30 MHz to 1000 MHz, and the thin broken line curve F2 of FIGS. 12 and 13 was obtained.

Next, in the structure shown in FIG. 11, the common mode choke coil array 120 shown in FIG. 14 is provided in place of the noise countermeasure component 1, and as shown in FIG. With the 124 connected to the ground layer 130, the noise radiation characteristic (Ssc12: dB) of the common mode was measured in the frequency range of 30 MHz to 1000 MHz, and a solid curve F3 in FIG. 12 was obtained. Further, under the same structure, the noise radiation characteristic (Ssd12: dB) of the differential mode was measured in the frequency range of 30 MHz to 1000 MHz, and a thin solid curve F4 in FIG. 12 was obtained.
As shown in FIG. 12, in such a structure, the solid curve F3 indicating the noise radiation characteristic in the common mode is higher than the dashed curve F1 indicating the noise radiation characteristic when the common mode choke coil array 120 is not provided. It can also be seen that the fine solid line curve F4 indicating the noise radiation characteristic in the differential mode is higher than the thin broken line curve F2 indicating the noise radiation characteristic when the common mode choke coil array 120 is not provided.

Finally, in the structure shown in FIG. 11, when the common mode noise radiation characteristic (Ssc12: dB) was measured in the frequency range of 30 MHz to 1000 MHz, a solid curve F5 in FIG. 13 was obtained. Moreover, when the noise radiation characteristic (Ssd12: dB) of the differential mode was measured in the frequency range of 30 MHz to 1000 MHz under the same structure, a thin solid curve F6 in FIG. 12 was obtained.
As shown in FIG. 13, in such a structure, the solid line curve F5 indicating the noise radiation characteristic in the common mode is lower than the broken line curve F1 indicating the noise radiation characteristic when the common mode choke coil array 120 is not provided. Further, it can be seen that the thin solid line curve F6 indicating the noise radiation characteristic in the differential mode is lower than the thin broken line curve F2 indicating the noise radiation characteristic when the common mode choke coil array 120 is not provided.
That is, it has been confirmed that by taking the noise countermeasure structure of this embodiment, good noise radiation characteristics can be obtained both in the common mode and in the differential mode.
Since other configurations, operations, and effects are the same as those in the first embodiment, description thereof is omitted.

In addition, this invention is not limited to the said Example, A various deformation | transformation and change are possible within the range of the summary of invention.
For example, in the above embodiment, a multilayer common mode choke coil array structure is exemplified as a noise countermeasure component. However, the present invention is not limited to the multilayer type, and a winding type component can also be applied as a noise countermeasure component. Of course you can.
Moreover, in the said Example, although the coil 31 and the coil 34 were formed on the same insulating layer 22, the example of the noise countermeasure component which formed the coil 32 and the coil 33 on the same insulating layer 25 was shown, The coil 31 and the coil 34 are not limited to being formed on the same layer, and the coil 32 and the coil 33 are not limited to being formed on the same layer.

It is a disassembled perspective view which shows the noise countermeasure component which concerns on 1st Example of this invention. It is an external view of the noise countermeasure component shown in FIG. FIG. 3 is a perspective view showing the inside of the noise countermeasure component of FIG. It is a top view which shows the connection state of a parallel circuit and an external terminal. It is a top view which shows the connection state of a pair of coil and an external terminal. It is process drawing which shows the manufacturing method of noise countermeasure components. It is sectional drawing which shows a lamination process. It is sectional drawing which shows a crimping | compression-bonding process. It is the schematic which shows a dicing process, a baking process, and an external terminal formation process. It is a schematic perspective view for demonstrating the noise countermeasure structure which concerns on 2nd Example of this invention. It is a circuit diagram which shows a noise countermeasure structure. It is a diagram which shows the noise radiation characteristic in the differential mode at the time of using the conventional noise countermeasure structure, and the noise radiation characteristic in the common mode. It is a diagram which shows the noise radiation characteristic in the differential mode at the time of using the noise countermeasure structure of an Example, and the noise radiation characteristic in the common mode. It is a circuit diagram which shows the conventional noise countermeasure structure using a common mode choke coil array.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Noise suppression component, 2 ... Laminate body, 2a ... Front surface, 2b ... Rear surface, 3-1, 3-2 ... Common mode choke coil part, 4-1-4-6 ... External terminal 21, 29 ... Magnetic body Substrate, 22-26 ... insulating layer, 23a, 23b, 26a, 26b ... through hole, 27, 28 ... adhesive layer, 31-34 ... coil, 35a, 35f, 36a, 36d, 37a, 37d ... end for connection, 35b, 35e ... linear pattern, 35c, 35d, 36c, 37c ... drawer pattern, 100 ... differential transmission cable, 110 ... connector, 111, 112 ... differential signal pin, 113 ... ground pin, 130 ... ground layer, 140 ... Electronic circuit components 141, 142 ... Differential signal lines, 143 ... Ground lines, 150 ... Substrate.

Claims (3)

A first coil and a second coil constituting a first common mode choke coil portion; a third coil constituting a second common mode choke coil portion adjacent to the first common mode choke coil portion; A noise countermeasure component comprising a fourth coil,
The first external terminal and the second external terminal for connecting to the ground line are connected to the first coil of the first common mode choke coil section and the fourth coil of the second common mode choke coil section. Connect to both ends of the parallel circuit formed in parallel,
A third external terminal and a fourth external terminal for connecting to one of the pair of differential signal lines are respectively connected to both ends of the second coil;
A fifth external terminal and a sixth external terminal for connecting to the other of the pair of differential signal lines are connected to both ends of the third coil, respectively.
Noise suppression parts characterized by this. In the noise countermeasure component according to claim 1,
The first common mode choke coil portion of the first common mode choke coil portion is laminated so as to face each other in the laminated body, and the second common mode choke coil portion is formed as the first common mode choke coil portion. And the third coil and the fourth coil of the second common mode choke coil portion are stacked so as to face each other in the stacked body.
The first external terminal, the third external terminal, and the fifth external terminal are juxtaposed on one outer surface of the laminate, and the second external terminal, the fourth external terminal, and the sixth external terminal are arranged. The external terminals are arranged side by side on the other outer surface facing the one outer surface.
Noise suppression parts characterized by this. On the board, a pair of differential signal lines and a ground line are extended from the pair of differential signal pins and ground pins of the connector on the board to a predetermined electronic circuit component and the ground layer of the board, respectively. To form a pattern,
The first external terminal and the second external terminal in the noise countermeasure component of claim 1 or claim 2 are connected to the ground line of the substrate,
The third external terminal and the fourth external terminal are connected to one of the pair of differential signal lines, and the fifth external terminal and the sixth external terminal are connected to the pair of differential signal lines. Connected to the other of the
A connection structure for noise suppression components.

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