Current control module, and battery and electronic device equipped with the same

Abstract

To provide a current control module with a shortened current path.SOLUTION: A current control module 10 includes a multilayer circuit board 100, a switching element 200 embedded in the multilayer circuit board 100, an external terminal 331 connected to a current port P1 of the switching element 200 and exposed on one surface 101 of the multilayer circuit board 100, and an external terminal 382 connected to a current port P2 of the switching element 200 and exposed on the other surface 102 of the multilayer circuit board 100.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present disclosure relates to a current control module, a battery including the same, and an electronic device.

Background Art

[0002] A current control circuit that controls charging and discharging of a battery may be modularized by being integrated on a multilayer circuit board.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in a general circuit module, since external terminals are provided only on one side as described in Patent Document 1, when configuring a current control module, the current mainly flows in the planar direction, and the current path tends to be long.

[0005] In the present disclosure, a technique for shortening the current path in a current control module is described.

Means for Solving the Problems

[0006] A current control module according to one aspect of the present disclosure includes a multilayer circuit board having a first surface and a second surface located on the opposite side of the first surface, a switching element embedded in the multilayer circuit board and having first and second current ports, a first external terminal connected to the first current port of the switching element and exposed on the first surface of the multilayer circuit board, and a second external terminal connected to the second current port of the switching element and exposed on the second surface of the multilayer circuit board.

Effects of the Invention

[0007] According to the present disclosure, in a current control module, a technique for shortening a current path is provided.

Brief Description of the Drawings

[0008]

Figure 1

Figure 2

Figure 3

Embodiments for Carrying Out the Invention

[0009] Hereinafter, embodiments of the technique according to the present disclosure will be described in detail with reference to the accompanying drawings.

[0010] FIG. 1 is a schematic cross-sectional view for explaining the structure of a current control module 10 according to an embodiment of the technique according to the present disclosure.

[0011] As shown in FIG. 1, the current control module 10 according to the present embodiment includes a multilayer circuit board 100 and a switching element 200 embedded in the multilayer circuit board 100. The multilayer circuit board 100 has a structure in which a plurality of conductor layers L1 to L4 and a plurality of insulating layers 111 to 113 are alternately laminated. The switching element 200 is embedded in the insulating layer 112. One surface 101 of the multilayer circuit board 100 is covered with a solder resist 121 except for the exposed portions of the external terminals. The other surface 102 of the multilayer circuit board 100 is covered with a solder resist 122 except for the exposed portions of the external terminals. The surfaces 101 and 102 are located on opposite sides of each other and are perpendicular to the lamination direction of the insulating layers 111 to 113. The overall thickness of the multilayer circuit board 100 including the solder resists 121 and 122 is about 350 μm, which is very thin.

[0012] The switching element 200 is a power semiconductor such as a transistor or a power IC, and has current ports P1 and P2. As an example, when the switching element 200 is a transistor, one of the current ports P1 and P2 is a source, and the other of the current ports P1 and P2 is a drain. The switching element 200 is controlled by a driver circuit (not shown). The driver circuit for controlling the switching element 200 may be embedded in the multilayer circuit board 100, or may be mounted on the surface of the multilayer circuit board 100.

[0013] The current port P1 of the switching element 200 is connected to an external terminal 331 exposed on one surface 101 of the multilayer circuit board 100 via via conductors 301, conductor pattern 311, and via conductor 321. The via conductors 301 and 321 are respectively embedded in insulating layers 112 and 111. The conductor pattern 311 and the external terminal 331 are respectively located in conductor layers L2 and L1. In the example shown in FIG. 1, most of the external terminal 331 overlaps with the switching element 200 in plan view. Therefore, the wiring distance between the current port P1 of the switching element 200 and the external terminal 331 is very short.

[0014] The current port P2 of the switching element 200 is connected to an external terminal 382 exposed on the other surface 102 of the multilayer circuit board 100 via via conductors 302, conductor pattern 312, via conductor 304, conductor pattern 362, and via conductor 372. The via conductors 302 and 304 are embedded in the insulating layer 112. The via conductor 362 is embedded in the insulating layer 113. The conductor pattern 312, the conductor pattern 362, and the external terminal 382 are respectively located in conductor layers L2 to L4. In the example shown in FIG. 1, the external terminal 382 is connected to a connector 352 via a conductive member 392 such as solder. The connector 352 is provided to establish an electrical connection with an external device by fitting with another connector provided in the external device.

[0015] The conductor layer L1 is further provided with a heat radiation terminal 333 that is exposed on one surface 101 of the multilayer circuit board 100. The heat radiation terminal 333 is connected to the switching element 200 via the via conductor 323, the conductor pattern 313, and the via conductor 303. The via conductors 323 and 303 are respectively embedded in the insulating layers 111 and 112. The conductor pattern 313 is located in the conductor layer L2. When the switching element 200 is a transistor, the via conductor 303 connected to the heat radiation terminal 333 may be in contact with the semiconductor substrate constituting the transistor. According to this, the heat generated by the switching of the transistor is efficiently transmitted to the heat radiation terminal 333. Also, when the switching element 200 is a power IC, the via conductor 303 connected to the heat radiation terminal 333 may be connected to the ground terminal provided in the power IC. According to this, the heat generated by the switching of the power IC is efficiently transmitted to the heat radiation terminal 333 via the ground terminal. In the example shown in FIG. 1, the entire heat radiation terminal 333 overlaps with the switching element 200 in a plan view. For this reason, the wiring distance between the switching element 200 and the heat radiation terminal 333 is very short.

[0016] The conductor layer L4 is further provided with land patterns 381, 383, and 384 that are exposed on one surface 102 of the multilayer circuit board 100. In the example shown in FIG. 1, passive components 401 and 402 such as capacitors and inductors are mounted on one surface 102 of the multilayer circuit board 100. A pair of terminal electrodes provided on the passive component 401 are respectively connected to the land patterns 381 and 384. A pair of terminal electrodes provided on the passive component 402 are respectively connected to the land patterns 383 and 384.

[0017] The land pattern 383 is connected to the conductor pattern 363 located in the conductor layer L3 via the via conductor 373 embedded in the insulating layer 113. The land pattern 381 is connected to the shield pattern 361 located in the conductor layer L3 via the via conductor 371 embedded in the insulating layer 113. The shield pattern 361 is provided at a position overlapping the switching element 200 in a plan view. The shield pattern 361 may cover most or the entire surface of the switching element 200. A ground potential may be applied to the shield pattern 361.

[0018] With such a configuration, the current control module 10 according to the present embodiment can flow a current from the external terminal 331 to the external terminal 382 or from the external terminal 382 to the external terminal 331 via the switching element 200. The amount of current is controlled by the switching element 200. Since the external terminals 331 and 382 are arranged on the front and back of the multilayer circuit board 100, the current path in the current control module 10 becomes very short, and the current path is reduced in resistance. Thereby, even when the amount of current is as large as 1 A or more, for example, heat generation of the current path can be suppressed. Moreover, since the current path is short, generation of electromagnetic noise from the current path is also suppressed. Further, since the shield pattern 361 is provided between the switching element 200 and the passive components 401 and 402, electromagnetic field interference between the two is also suppressed.

[0019] FIG. 2 is a schematic diagram for explaining a configuration according to a first example of the electronic device 50 using the current control module 10 according to the present embodiment.

[0020] In the example shown in FIG. 2, the battery body 20 and the device body 30 are arranged so as to sandwich the current control module 10 in the stacking direction. The battery body 20 is, for example, a secondary battery, serves to supply power to the device body 30, and is charged by a battery charger included in the device body 30.

[0021] The battery body 20 has a power supply terminal 21 and a ground terminal 22. The power supply terminal 21 and the ground terminal 22 of the battery body 20 are respectively connected to the external terminal 331 and the heat dissipation terminal 333 of the current control module 10 via conductive members 391 and 393 such as solder. The current control module 10 and the battery body 20 constitute a battery 40. That is, the current control module 10 is a part of the battery 40. The device body 30 has a connector 31 that constitutes a power supply terminal. The connector 31 of the device body 30 fits with the connector 352 of the current control module 10.

[0022] Thereby, the battery body 20 and the device body 30 are connected via the current control module 10. As described above, since the multilayer circuit board 100 constituting the current control module 10 is very thin, the space required between the battery body 20 and the device body 30 for arranging the current control module 10 can be reduced, and the current path 60 between the two can be shortened. In addition, since the shield pattern 361 is provided in the current control module 10, electromagnetic field interference between the battery body 20 and the device body 30 is also suppressed.

[0023] In addition, since the heat dissipation terminal 333 is arranged at a position overlapping the switching element 200, the heat generated by the switching element 200 is efficiently transmitted to the battery body 20 via the heat dissipation terminal 333 and the ground terminal 22. Thereby, it is possible to obtain high heat dissipation characteristics. In addition, since the heat generated by the switching element 200 is also dissipated via the external terminal 331, higher heat dissipation characteristics can be obtained if the external terminal 331 is arranged at a position overlapping the switching element 200. The heat generated by the switching element 200 is also dissipated to the device body 30 side via the external terminal 382.

[0024] In the example shown in FIG. 2, since the current control module 10 and the device main body 30 are connected via a connector, for example, when the battery main body 20 deteriorates or malfunctions, by disconnecting the connection by the connector, the battery 40 composed of the battery main body 20 and the current control module 10 can be replaced with a new one.

[0025] FIG. 3 is a schematic diagram for explaining the configuration according to a second example of the electronic device 50 using the current control module 10 according to the present embodiment.

[0026] In the example shown in FIG. 3, contact pins 32 are provided on the device main body 30 instead of a connector. The tip of the contact pin 32 contacts the external terminal 382. Thereby, for example, when the battery main body 20 deteriorates or malfunctions, the battery 40 composed of the battery main body 20 and the current control module 10 can be replaced with a new one.

[0027] Although the embodiments of the technology according to the present disclosure have been described above, the technology according to the present disclosure is not limited to the above embodiments, and various modifications can be made without departing from the gist thereof, and it goes without saying that those are also included in the scope of the technology according to the present disclosure.

[0028] The technology according to the present disclosure includes, but is not limited to, the following configuration examples.

[0029] The current control module according to one aspect of the present disclosure includes a multilayer circuit board having a first surface and a second surface located on the opposite side of the first surface, a switching element embedded in the multilayer circuit board and having first and second current ports, a first external terminal connected to the first current port of the switching element and exposed on the first surface of the multilayer circuit board, and a second external terminal connected to the second current port of the switching element and exposed on the second surface of the multilayer circuit board. According to this, it is possible to shorten the current path between the first external terminal and the second external terminal.

[0030] In the above-described current control module, the multilayer circuit board may include a shield pattern disposed between the switching element and the second surface. According to this, it is possible to reduce electromagnetic interference between the front and back surfaces of the multilayer circuit board.

[0031] In the above-described current control module, at least one of the first and second external terminals may be disposed at a position overlapping the switching element. According to this, it is possible to further shorten the current path.

[0032] The above-described current control module may further include a heat dissipation terminal that is connected to the switching element, disposed at a position overlapping the switching element, and exposed on the first surface of the multilayer circuit board. According to this, it is possible to enhance the heat dissipation characteristics of the switching element.

[0033] A battery according to one aspect of the present disclosure includes a battery body having a first power supply terminal, and the above-described current control module disposed so as to overlap the battery body, and the first power supply terminal of the battery body is connected to the first external terminal of the current control module. According to this, it is possible to shorten the current path between the battery body and the switching element.

[0034] An electronic device according to one aspect of the present disclosure includes a device body having a second power supply terminal, and the above-described battery, and the current control module is disposed so as to be sandwiched between the battery and the device body, and the second power supply terminal of the device body is connected to the second external terminal of the current control module. According to this, it is possible to shorten the current path between the battery and the device body.

[0035] In the above-described electronic device, the second power supply terminal of the device body may be a connector or a contact pin. According to this, it is easy to attach and detach the device body and the battery.

Description of Signs

[0036] 10 Current control module 20 Battery body 21 Power supply terminal 22 Ground terminal 30 Equipment body 31 Connector 32 Contact pin 40 Battery 50 Electronic device 60 Current path 100 Multilayer circuit board 101, 102 Surfaces of the multilayer circuit board 111~113 Insulating layer 121, 122 Solder resist 200 Switching element 301~304, 321, 323, 362, 371~373 Via conductor 311~313, 362, 363 Conductor pattern 331, 382 External terminal 333 Heat dissipation terminal 352 Connector 361 Shield pattern 381, 383, 384 Land pattern 391~393 Conductive member 401, 402 Passive component 402 Passive component L1~L4 Conductor layer P1, P2 Current port

Claims

1. A multilayer circuit board having a first surface and a second surface located on the opposite side of the first surface; A switching element embedded in the multilayer circuit board and having first and second current ports; A first external terminal connected to the first current port of the switching element and exposed on the first surface of the multilayer circuit board; A second external terminal connected to the second current port of the switching element and exposed on the second surface of the multilayer circuit board; A current control module comprising the above.

2. The multilayer circuit board includes a shield pattern disposed between the switching element and the second surface, The current control module according to claim 1.

3. At least one of the first and second external terminals is disposed at a position overlapping the switching element, The current control module according to claim 1.

4. Further comprising a heat dissipation terminal connected to the switching element, disposed at a position overlapping the switching element, and exposed on the first surface of the multilayer circuit board, The current control module according to claim 1.

5. A battery body having a first power terminal; The current control module according to any one of claims 1 to 4, disposed so as to overlap the battery body, and The first power terminal of the battery body is connected to the first external terminal of the current control module, A battery.

6. An equipment body having a second power terminal; The battery according to claim 5, and The current control module is disposed so as to be sandwiched between the battery and the equipment body, The second power terminal of the equipment body is connected to the second external terminal of the current control module, An electronic device.

7. The second power terminal of the equipment body is a connector or a contact pin, The electronic device according to claim 6.

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