JP7582476B2 - Composite coil components and electronic circuit units - Google Patents

Description

The present invention relates to a composite coil component and an electronic circuit unit.

Patent documents 1 and 2 describe circuits that transmit differential signals and DC currents by superimposing them on a differential transmission line.

JP 2019-213186 A JP 2019-201237 A

In the circuit described in Patent Document 1, there are two coils that supply DC power. The fact that there are two coils that supply DC power places restrictions on the characteristics of the common mode choke coil that is connected. Therefore, if there is only one coil that supplies DC power, as in Patent Document 2, there is a possibility that unnecessary radiation caused by this coil cannot be suppressed.

The present invention has been made in consideration of the above, and aims to provide a composite coil component and an electronic circuit unit that consolidates the coil that supplies DC power into a single coil while suppressing unnecessary radiation caused by the coil that supplies DC power.

A composite coil component according to one aspect of the present invention comprises a magnetic support, a first electrode pair, a second electrode pair, and a third electrode supported by the support, two first coils wound around the support to form a first common mode choke coil, two second coils wound around the support to form a second common mode choke coil, and a third coil wound around the support, one end of each of the two first coils is connected to each electrode of the first electrode pair, one end of each of the two second coils is connected to each electrode of the second electrode pair, one end of the third coil is connected to the third electrode, the other end of one of the two first coils is electrically connected to the other end of one of the two second coils, and the other end of the third coil, and the other end of the other of the two first coils is electrically connected to the other end of the other of the two second coils.

The electronic circuit unit of another aspect of the present invention is an electronic circuit unit connected to a differential transmission line, and includes an integrated circuit, a power supply circuit, and a composite coil component including a first electrode pair connected to the integrated circuit, a second electrode pair connected to the differential transmission line, and a third electrode connected to the power supply circuit, and the composite coil component includes a magnetic support body, the first electrode pair, the second electrode pair, and the third electrode supported by the support body, two first coils wound around the support body to form a first common mode choke coil, and a second common mode choke coil wound around the support body. The support includes two second coils that serve as arc coils, and a third coil that is wound around the support, one ends of the two first coils are connected to each electrode of the first electrode pair, one ends of the two second coils are connected to each electrode of the second electrode pair, one end of the third coil is connected to the third electrode, the other end of one of the two first coils, the other end of one of the two second coils, and the other end of the third coil are electrically connected, and the other end of the other of the two first coils and the other end of the other of the two second coils are electrically connected.

The present invention makes it possible to increase the degree of freedom in the characteristics of the common mode choke coil and suppress unnecessary radiation caused by the coil that supplies DC power.

FIG. 1 is an equivalent circuit diagram of an electronic circuit unit connected to a differential transmission line according to the first embodiment. FIG. 2 is a front view showing the configuration of the composite coil component of the first embodiment. FIG. 3 is a bottom view of FIG. FIG. 4 is a side view of the first side of FIG. FIG. 5 is a side view of the second side of FIG. FIG. 6 is an explanatory diagram for explaining an example of frequency characteristics of the composite coil component of the first embodiment. FIG. 7 is a diagram illustrating an example of frequency characteristics of the composite coil component of the first embodiment. FIG. 8 is an equivalent circuit diagram of an electronic circuit unit connected to a differential transmission line of the second embodiment. FIG. 9 is a front view showing the configuration of a composite coil component according to the second embodiment. FIG. 10 is a bottom view of FIG. FIG. 11 is a front view showing the configuration of a composite coil component according to the third embodiment. FIG. 12 is a bottom view of FIG. FIG. 13 is a side view of the first side of FIG.

The following describes the embodiments in detail with reference to the drawings. Note that the present invention is not limited to these embodiments. Each embodiment is merely an example, and it goes without saying that partial substitution or combination of the configurations shown in different embodiments is possible. From the second embodiment onwards, a description of matters common to the first embodiment will be omitted, and only the differences will be described. In particular, similar effects resulting from similar configurations will not be mentioned in each embodiment.

(Embodiment 1)
1 is an equivalent circuit diagram of an electronic circuit unit connected to a differential transmission line of embodiment 1. The electronic circuit unit 100 has a main line 60 and an electronic circuit module 40 to which the main line 60 is connected. The main line 60 is a differential transmission line. Signal lines of the main line 60 are connected to external connection terminals 43 and 44 of the electronic circuit module 40, respectively.

In the electronic circuit module 40, an integrated circuit 41, a power supply circuit 42, and a composite coil component 20 are mounted on a printed circuit board. The integrated circuit 41 is a so-called electronic control unit, and transmits and receives differential signals via the main line 60 with other devices connected to the main line 60. The electronic control unit includes a communication circuit for transmitting and receiving and a termination circuit (terminator). The electronic control unit may include the integrated circuit 41 and other electronic components on the printed circuit board.

The power supply circuit 42 superimposes a power supply current on one of the signal lines of the main line 60. In the differential transmission line of the main line 60, a differential signal and a direct current are superimposed, and the differential signal and the direct current are transmitted to other devices. The power supply circuit 42 may be included in the integrated circuit 41.

The composite coil component 20 includes a first common mode choke coil 31, a second common mode choke coil 32, and a third coil 33. The impedance of each of the first common mode choke coil 31 and the second common mode choke coil 32 is the same as the impedance of the main line 60. The first common mode choke coil 31 includes two first coils. One end of each of the two first coils is connected to each electrode of the first electrode pair 11. Each electrode of the first electrode pair 11 is connected to the integrated circuit 41.

The second common mode choke coil 32 includes two second coils. One end of each of the two second coils is connected to each of the electrodes of the second electrode pair 12. Each of the electrodes of the second electrode pair 12 is connected to the external connection terminals 43, 44, respectively.

One end of the third coil 33 is connected to the third electrode 13. The third electrode 13 is connected to the power supply circuit 42. The third coil 33 also becomes part of a circuit (Bias-T circuit) that prevents high-frequency components of the differential signal from being transmitted to the power supply circuit 42, which has a low load impedance.

In the first auxiliary electrode 14, the other end of one of the two first coils that form the first common mode choke coil 31, the other end of one of the two second coils that form the second common mode choke coil 32, and the other end of the third coil 33 are electrically connected. In the second auxiliary electrode 15, the other end of the other of the two first coils is connected to the other end of the other of the two second coils. As a result, in the first auxiliary electrode 14 and the second auxiliary electrode 15 provided in the composite coil component 20, the third coil 33 is connected to the first common mode choke coil 31 and the second common mode choke coil 32, and therefore the composite coil component 20 can be made smaller.

Figure 2 is a front view showing the configuration of the composite coil component of embodiment 1. Figure 3 is a bottom view of Figure 2. Figure 4 is a side view of the first side of Figure 2. Figure 5 is a side view of the second side of Figure 2. As shown in Figures 2 to 5, the support body 28 includes a first core portion 21, a first flange portion 22, a second flange portion 23, a third flange portion 24, a top plate portion 25, and a second core portion 26. The first core portion 21, the first flange portion 22, the second flange portion 23, the third flange portion 24, the top plate portion 25, and the second core portion 26 are formed of a magnetic material such as Ni-Zn ferrite.

The first core portion 21 is sandwiched between the first flange portion 22 and the second flange portion 23. The second core portion 26 is sandwiched between the second flange portion 23 and the third flange portion 24. The first flange portion 22, the second flange portion 23, and the third flange portion 24 are larger than the outer shapes of the first core portion 21 and the second core portion 26. The first core portion 21, the first flange portion 22, the second flange portion 23, the third flange portion 24, and the second core portion 26 are integrally molded.

The first electrode pair 11, the second electrode pair 12, the third electrode 13, the first auxiliary electrode 14, and the second auxiliary electrode 15 are conductors such as Au, Cu, or an alloy thereof. The first electrode pair 11 and the third electrode 13 are provided on the bottom surface of the first flange 22. The first auxiliary electrode 14 and the second auxiliary electrode 15 are provided on the bottom surface of the second flange 23. The second electrode pair 12 is provided on the bottom surface of the third flange 24. The first electrode pair 11, the second electrode pair 12, the third electrode 13, the first auxiliary electrode 14, and the second auxiliary electrode 15 are arranged at different positions on the bottom surface of the support 28. Here, the bottom surface of the support 28 faces the printed circuit board of the electronic circuit module 40 (see FIG. 1).

The first core portion 21 is, for example, a rectangular prism or a cylinder. Similarly, the second core portion 26 is, for example, a rectangular prism or a cylinder. Two first coils that become the first common mode choke coil 31 are wound around the first core portion 21. A third coil 33 is wound around the first core portion 21 so as to overlap the first coil. Two second coils that become the second common mode choke coil 32 are wound around the second core portion 26. Since the first common mode choke coil 31 and the third coil 33 are wound around the same first core portion 21, the composite coil component 20 can be made smaller.

As shown in FIG. 3, one end of each of the two first coils that form the first common mode choke coil 31 is connected to each electrode of the first electrode pair 11. The other ends of the two first coils are connected to the first auxiliary electrode 14 and the second auxiliary electrode 15, respectively. One end of each of the two second coils that form the second common mode choke coil 32 is connected to each electrode of the second electrode pair 12. The other ends of the two second coils are connected to the first auxiliary electrode 14 and the second auxiliary electrode 15, respectively. One end of the third coil 33 is connected to the third electrode 13. The other end of the third coil 33 is connected to the first auxiliary electrode 14.

The top plate portion 25 covers the upper surface of the support body 28. The top plate portion 25 is in contact with the first flange portion 22, the second flange portion 23, and the third flange portion 24, forming a closed magnetic circuit.

6 and 7 are explanatory diagrams for explaining an example of the frequency characteristics of the composite coil component of embodiment 1. The horizontal axis of FIG. 6 represents frequency, and the vertical axis represents the mode conversion transmission characteristic (Scd21) from differential mode to common mode of the S parameter. The horizontal axis of FIG. 7 represents frequency, and the vertical axis represents the mode conversion reflection characteristic (Scd22) of the S parameter. In the evaluation examples shown in FIG. 6 and FIG. 7, the comparative example is the equivalent circuit shown in Patent Document 2, and the example is the equivalent circuit of embodiment 1. In other words, the comparative example does not have the second common mode choke coil 32 of embodiment 1.

In the comparative example, the third coil provides inductance to only one of the signal lines of the differential transmission line, so there is concern about degradation of the mode conversion characteristics (Scd21 and Scd22). In contrast, in the embodiment, even if part of the differential signal is converted to common mode by the inductance component of the third coil 33, the second common mode choke coil 32 increases the common mode attenuation. As a result, as shown in Figures 6 and 7, the embodiment including the second common mode choke coil 32 has improved mode conversion characteristics (Scd21 and Scd22) compared to the comparative example.

As described above, the composite coil component 20 of the first embodiment includes a magnetic support 28, a first electrode pair 11, a second electrode pair 12, and a third electrode 13 provided on the support 28, two first coils that form the first common mode choke coil 31, two second coils that form the second common mode choke coil 32, and a third coil 33. The first common mode choke coil 31, the second common mode choke coil 32, and the third coil 33 are wound around the support 28.

As a result, the first common mode choke coil 31, the second common mode choke coil 32, and the third coil 33 are integrated together. In the composite coil component 20 of embodiment 1, the number of components mounted on the printed circuit board of the electronic circuit module 40 is reduced, compared to when the first common mode choke coil 31, the second common mode choke coil 32, and the third coil 33 are each formed as separate components, and the cost of the electronic circuit module 40 is reduced.

In addition, since the third coil 33 that constitutes the Bias-T circuit, and the first common mode choke coil 31 and the second common mode choke coil 32 are wound around a common support 28, the composite coil component 20 can be made smaller.

The electronic circuit unit 100 superimposes a power supply current on one of the signal lines of the main line 60, which is a differential transmission line. Compared to connecting inductors to both of the signal lines of the main line 60, which is a differential transmission line, connecting an inductor to one of the signal lines of the main line 60, which is a differential transmission line, reduces restrictions on the coil winding diameter and core material of the first common mode choke coil 31 to be selected, and the degree of freedom in the characteristics of the first common mode choke coil 31 can be increased.

Furthermore, the composite coil component 20 can improve the mode conversion characteristics, thereby suppressing unnecessary radiation caused by the third coil 33 that constitutes the Bias-T circuit.

(Embodiment 2)
8 is an equivalent circuit diagram of an electronic circuit unit connected to a differential transmission line of embodiment 2. The equivalent circuit of the electronic circuit unit 100 of embodiment 2 differs from embodiment 1 in that it includes a capacitor C1. In embodiment 2, the same components as those in embodiment 1 are denoted by the same reference numerals, and detailed description thereof will be omitted.

As shown in Figure 8, a capacitor C1 is connected between the first coil of the first common mode choke coil 31 and the second coil of the second common mode choke coil 32. The capacitor C1, together with the third coil 33, forms part of the noise filter circuit (Bias-T circuit).

Figure 9 is a front view showing the configuration of the composite coil component of embodiment 2. Figure 10 is a bottom view of Figure 9. As shown in Figures 9 and 10, the composite coil component 20 includes a first common mode choke coil 31, a second common mode choke coil 32, a third coil 33, and two capacitors C1.

9 and 10, the first auxiliary electrode 14 is divided by a slit SL into electrode piece 14A and electrode piece 14B. The second auxiliary electrode 15 is divided by a slit SL into electrode piece 15A and electrode piece 15B. Each terminal of one capacitor C1 is electrically connected to electrode piece 14A and electrode piece 14B, respectively. Each terminal of the other capacitor C1 is electrically connected to electrode piece 15A and electrode piece 15B.

As described above, since the capacitor C1 is connected between each of the first coil of the first common mode choke coil 31 and the second coil of the second common mode choke coil 32, the high frequency components of the differential signal are less likely to be transmitted to the power supply circuit 42, which has a lower load impedance, than in embodiment 1.

In the composite coil component 20 of embodiment 2, the number of components mounted on the printed circuit board of the electronic circuit module 40 is reduced compared to when the first common mode choke coil 31, the second common mode choke coil 32, the third coil 33 and the capacitor C1 are each individual components, thereby reducing the cost of the electronic circuit module 40.

(Embodiment 3)
Fig. 11 is a front view showing the configuration of a composite coil part of embodiment 3. Fig. 12 is a bottom view of Fig. 11. Fig. 13 is a side view of the first side surface of Fig. 11. The second side surface of the support body 29 is the same as that of Fig. 5, and therefore description thereof will be omitted. The composite coil part 20 of embodiment 3 differs from embodiment 1 in that it does not include a second core portion 26. Note that in embodiment 3, the same components as those of embodiment 1 are denoted by the same reference numerals, and detailed description thereof will be omitted.

The support 29 includes a first core portion 21, a first flange portion 22, a second flange portion 23, a third flange portion 24, and a top plate portion 25. The first core portion 21, the first flange portion 22, the second flange portion 23, the third flange portion 24, and the top plate portion 25 are formed of a magnetic material such as Ni-Zn ferrite.

The first core portion 21 is sandwiched between the second flange portion 23 and the third flange portion 24. The first flange portion 22, the second flange portion 23, and the third flange portion 24 are larger than the outer shape of the first core portion 21. The first core portion 21, the first flange portion 22, the second flange portion 23, and the third flange portion 24 are integrally molded. Each electrode of the first electrode pair 11 and each electrode of the second electrode pair 12 are divided by a slit SL2.

The top plate portion 25 covers the upper surface of the support body 28. The top plate portion 25 is in contact with the first flange portion 22, the second flange portion 23, and the third flange portion 24, forming a closed magnetic circuit.

The first core portion 21 is, for example, a rectangular prism or a cylinder. Two first coils that become the first common mode choke coil 31 are wound around the first core portion 21. Two second coils that become the second common mode choke coil 32 are wound around the first core portion 21. A third coil 33 is wound around the first core portion 21 so as to overlap the first coils and the second coils.

As a result, the first common mode choke coil 31, the second common mode choke coil 32, and the third coil 33 are integrated together. In the composite coil component 20 of embodiment 3, the number of components mounted on the printed circuit board of the electronic circuit module 40 is reduced, compared to when the first common mode choke coil 31, the second common mode choke coil 32, and the third coil 33 are each formed as separate components, and the cost of the electronic circuit module 40 is reduced.

In addition, since the third coil 33 that constitutes the Bias-T circuit, and the first common mode choke coil 31 and second common mode choke coil 32 are wound around a common first core portion 21, the composite coil component 20 can be made smaller.

In addition, the composite coil part 20 of embodiment 3 may also be provided with the capacitor C1 of embodiment 2.

The above-described embodiment is intended to facilitate understanding of the present invention, and is not intended to limit the present invention. The present invention may be modified or improved without departing from the spirit of the present invention, and equivalents thereof are also included in the present invention.

Reference Signs List 11 First electrode pair 12 Second electrode pair 13 Third electrode 14 First auxiliary electrode 15 Second auxiliary electrode 20 Composite coil component 21 First core portion 26 Second core portion 28, 29 Support body 31 First common mode choke coil 32 Second common mode choke coil 33 Third coil 41 Integrated circuit 42 Power supply circuit 60 Main line 100 Electronic circuit unit C1 Capacitor

Claims (6)

A magnetic support;
a first electrode pair, a second electrode pair, and a third electrode provided on the support;
Two first coils wound around the support to form first common mode choke coils;
Two second coils wound around the support to form second common mode choke coils;
and a third coil wound around the support,
one end of each of the first coils is connected to each of the first electrodes of the first electrode pair;
one end of each of the second coils is connected to each of the electrodes of the second electrode pair;
One end of the third coil is connected to the third electrode,
the other end of one of the two first coils, the other end of one of the two second coils, and the other end of the third coil are electrically connected to each other;
the other end of the other of the two first coils is electrically connected to the other end of the other of the two second coils;
Composite coil parts. Further comprising a first auxiliary electrode and a second auxiliary electrode,
the other end of one of the two first coils, the other end of one of the two second coils, and the other end of the third coil are electrically connected to the first auxiliary electrode;
the other end of the other of the two first coils is electrically connected to the other end of the other of the two second coils in the second auxiliary electrode;
The composite coil component according to claim 1 . The composite coil component according to claim 1, wherein a capacitor is connected between the other end of one of the two first coils and the other end of one of the two second coils. The support includes a first core portion and a second core portion,
the first coil and the third coil are wound around the first core portion,
The composite coil component according to claim 1 , wherein the second coil is wound around the second core portion. The support body includes a first core portion,
The composite coil component according to claim 1 , wherein the first coil, the second coil, and the third coil are wound around the first core portion. An electronic circuit unit connected to a differential transmission line,
An integrated circuit;
A power supply circuit;
a composite coil component including a first electrode pair connected to the integrated circuit, a second electrode pair connected to the differential transmission line, and a third electrode pair connected to the power supply circuit,
The composite coil component includes:
A magnetic support;
the first electrode pair, the second electrode pair, and the third electrode supported by the support;
Two first coils wound around the support to form first common mode choke coils;
Two second coils wound around the support to form second common mode choke coils;
and a third coil wound around the support,
one end of each of the first coils is connected to each of the first electrodes of the first electrode pair;
one end of each of the second coils is connected to each of the electrodes of the second electrode pair;
One end of the third coil is connected to the third electrode,
the other end of one of the two first coils, the other end of one of the two second coils, and the other end of the third coil are electrically connected to each other;
the other end of the other of the two first coils is electrically connected to the other end of the other of the two second coils;
Electronic circuit unit.

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