Isolator

Abstract

To provide an isolator capable of having a compact size.SOLUTION: An isolator 1 of an embodiment comprises: a first semiconductor chip 10; a second semiconductor chip 20; a first wiring board 30 that has a first surface P1 directed in a first direction Z on which the first semiconductor chip is provided; a second wiring board 40 that has a second surface P3 directed in the first direction on which the second semiconductor chip is provided and that is spaced apart from the first wiring board in a second direction X; a third wiring board 50 that is spaced apart from the first and second wiring boards in the first direction; a first coil 31a provided on the first surface of the first wiring board; a second coil 41a provided on the second surface of the second wiring board; a third coil 51a that is provided on a third surface P6 of the third wiring board facing the first surface of the first wiring board and the second surface of the second wiring board and that faces the first coil; a fourth coil 52a that is provided on a third surface of the third wiring board, faces the second coil, and is electrically connected to the third coil; and an insulator 100 provided over the first coil to the fourth coil.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] FIELD OF THE INVENTION An embodiment of the present invention relates to an isolator. [Background technology]

[0002] 2. Description of the Related Art An isolator is known that transmits a signal from a transmitting circuit to a receiving circuit while isolating the transmitting circuit from the receiving circuit. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-150579 [Patent Document 2] Patent Publication No. 2021-150830 [Patent Document 3] Patent Publication No. 2021-5598 Summary of the Invention [Problem to be solved by the invention]

[0004] To provide an isolator capable of reducing size. [Means for solving the problem]

[0005] An isolator according to an embodiment includes a first semiconductor chip, a second semiconductor chip, a first wiring board, a second wiring board, a third wiring board, a first coil, a second coil, a third coil, a fourth coil, and an insulator. The first semiconductor chip is provided on a first surface of the first wiring board facing a first direction. The second semiconductor chip is provided on a second surface of the second wiring board facing the first direction. The second wiring board is spaced apart from the first wiring board in a second direction intersecting the first direction. The third wiring board is spaced apart from each of the first wiring board and the second wiring board in the first direction. The first coil is provided on the first surface of the first wiring board and electrically connected to the first semiconductor chip. The second coil is provided on the second surface of the second wiring board and electrically connected to the second semiconductor chip. The third coil is provided on a third surface of the third wiring board facing the first surface of the first wiring board and the second surface of the second wiring board, and faces the first coil. The fourth coil is provided on the third surface of the third wiring board, faces the second coil, and is electrically connected to the third coil. Insulators are provided between the first coil and the second coil, between the first coil and the third coil, between the second coil and the fourth coil, and between the third coil and the fourth coil. [Brief explanation of the drawings]

[0006] [Figure 1] FIG. 1 is a circuit diagram showing an example of a circuit configuration of an isolator according to the first embodiment. [Figure 2] FIG. 2 is a plan view showing an example of the planar structure of the isolator according to the first embodiment. [Figure 3] FIG. 3 is a plan view showing an example of the planar structure of the isolator according to the first embodiment. [Figure 4] FIG. 4 is a plan view showing an example of the planar structure of the isolator according to the first embodiment. [Figure 5] FIG. 5 is a cross-sectional view showing an example of the cross-sectional structure of the isolator according to the first embodiment. [Figure 6] FIG. 6 is a cross-sectional view showing an example of the cross-sectional structure of the isolator according to the first embodiment. [Figure 7]FIG. 7 is a cross-sectional view showing an example of a cross-sectional structure of an isolator according to a first modification of the first embodiment. [Figure 8] FIG. 8 is a cross-sectional view showing an example of a cross-sectional structure of an isolator according to a first modification of the first embodiment. [Figure 9] FIG. 9 is a plan view showing an example of the planar structure of an isolator according to a second modified example of the first embodiment. [Figure 10] FIG. 10 is a plan view showing an example of the planar structure of an isolator according to a second modified example of the first embodiment. [Figure 11] FIG. 11 is a cross-sectional view showing an example of a cross-sectional structure of an isolator according to a second modification of the first embodiment. [Figure 12] FIG. 12 is a cross-sectional view showing an example of a cross-sectional structure of an isolator according to a second modification of the first embodiment. [Figure 13] FIG. 13 is a plan view showing an example of the planar structure of the isolator according to the second embodiment. [Figure 14] FIG. 14 is a plan view showing an example of the planar structure of the isolator according to the second embodiment. [Figure 15] FIG. 15 is a plan view showing an example of the planar structure of the isolator according to the second embodiment. [Figure 16] FIG. 16 is a cross-sectional view showing an example of the cross-sectional structure of the isolator according to the second embodiment. [Figure 17] FIG. 17 is a cross-sectional view showing an example of the cross-sectional structure of the isolator according to the second embodiment. [Figure 18] FIG. 18 is a cross-sectional view showing an example of a cross-sectional structure of an isolator according to a first modification of the second embodiment. [Figure 19] FIG. 19 is a cross-sectional view showing an example of a cross-sectional structure of an isolator according to a first modification of the second embodiment. [Figure 20] FIG. 20 is a plan view showing an example of a planar structure of an isolator according to a second modification of the second embodiment. [Figure 21] FIG. 21 is a plan view showing an example of a planar structure of an isolator according to a second modification of the second embodiment. [Figure 22] FIG. 22 is a cross-sectional view showing an example of a cross-sectional structure of an isolator according to a second modification of the second embodiment. [Figure 23] FIG. 23 is a cross-sectional view showing an example of a cross-sectional structure of an isolator according to a second modification of the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0007] Hereinafter, embodiments will be described with reference to the drawings. The dimensions and ratios of the drawings are not necessarily the same as those in reality. In the following description, components having substantially the same functions and configurations are given the same reference numerals, and repeated description may be omitted. When elements having similar configurations are particularly distinguished from one another, different letters or numbers may be added to the end of the same reference numerals. Furthermore, all descriptions of one embodiment also apply to descriptions of other embodiments, unless explicitly or obviously excluded.

[0008] 1. First embodiment An isolator according to a first embodiment will be described below. In the following, an isolator capable of transmitting a signal from a transmitting circuit (primary circuit) to a receiving circuit (secondary circuit) by magnetically coupling a coil connected to the transmitting circuit and a coil connected to the receiving circuit while isolating the transmitting circuit from the receiving circuit will be described as an example.

[0009] 1.1 Isolator circuit configuration The circuit configuration of an isolator will be described with reference to Fig. 1. Fig. 1 is a circuit diagram showing an example of the circuit configuration of an isolator.

[0010] The isolator 1 is, for example, a semiconductor package. In the example of Figure 1, the isolator 1 is a two-channel isolator. The isolator 1 transmits signals from a transmitting circuit to a receiving circuit for each channel while isolating the transmitting circuit from the receiving circuit. Hereinafter, the two channels will be referred to as the "first channel" and the "second channel," respectively. Components corresponding to the first channel will be denoted by adding "a" to the end of their reference symbols. Components corresponding to the second channel will be denoted by adding "b" to the end of their reference symbols. Note that the isolator 1 may be a one-channel isolator or an isolator with three or more channels.

[0011] The isolator 1 includes semiconductor chips (hereinafter referred to as "chips") 10 and 20, external electrode terminals T1a, T1b, T2a, and T2b, coils 31a, 31b, 41a, 41b, 51a, 51b, 52a, and 52b, and wirings 53a, 53b, 54a, and 54b.

[0012] The chip 10 is, for example, an IC (Integrated Circuit) chip. The chip 10 corresponds to a transmitting circuit. The chip 10 includes, for example, electronic circuits 11a and 11b and transmitting circuits 12a and 12b. Details of the electronic circuits 11a and 11b and the transmitting circuits 12a and 12b will be described later. A power supply voltage VDD and a ground voltage VSS are supplied to the chip 10.

[0013] The chip 20 is, for example, an IC chip. The chip 20 corresponds to a receiving circuit. The chip 20 includes, for example, receiving circuits 21a and 21b and electronic circuits 22a and 22b. Details of the receiving circuits 21a and 21b and the electronic circuits 22a and 22b will be described later. A power supply voltage VDD and a ground voltage VSS are supplied to the chip 20.

[0014] In the following, the circuit that transmits signals corresponding to the first channel will be referred to as the "first transmission circuit TCa," and the circuit that transmits signals corresponding to the second channel will be referred to as the "second transmission circuit TCb," and the components of the isolator 1 will be explained for each transmission circuit.

[0015] The first transmission circuit TCa includes an external electrode terminal T1a, an electronic circuit 11a, a transmission circuit 12a, coils 31a, 41a, 51a, and 52a, wires 53a and 54a, a reception circuit 21a, an electronic circuit 22a, and an external electrode terminal T2a.

[0016] An external signal IN1a is input to the external electrode terminal T1a.

[0017] The electronic circuit 11a includes, for example, a modulation circuit, which modulates (for example, amplitude shift keying) an input signal IN1a received from the outside via an external electrode terminal T1a, and transmits the modulated signal S1a to the transmission circuit 12a.

[0018] The transmission circuit 12a includes, for example, an oscillator OSC and a power amplifier PA.

[0019] The oscillator OSC generates an inverted signal S2ma of the signal S1a based on the signal S1a received from the electronic circuit 11a. The oscillator OSC transmits the received signal S1a as a non-inverted signal S2pa to the non-inverting input terminal of the power amplifier PA. The oscillator OSC transmits the generated inverted signal S2ma to the inverting input terminal of the power amplifier PA.

[0020] The power amplifier PA amplifies the non-inverted signal S2pa received from the oscillator OSC and transmits the amplified non-inverted signal S3pa to one end of the coil 31a. The power amplifier PA amplifies the inverted signal S2ma received from the oscillator OSC and transmits the amplified inverted signal S3ma to the other end of the coil 31a.

[0021] One end of the coil 31a is connected to the non-inverting output terminal of the power amplifier PA. The other end of the coil 31a is connected to the inverting output terminal of the power amplifier PA. Hereinafter, of the two ends of the coil 31a, the end connected to the non-inverting output terminal of the power amplifier PA will be referred to as the "first end," and the end connected to the inverting output terminal of the power amplifier PA will be referred to as the "second end."

[0022] The coil 41a is disposed at a distance from the coil 31a. One end of the coil 41a is connected to the inverting input terminal of the amplifier AMP, which will be described later. The other end of the coil 41a is connected to the non-inverting input terminal of the amplifier AMP. Hereinafter, of the two ends of the coil 41a, the end connected to the inverting input terminal of the amplifier AMP will also be referred to as the "first end," and the end of the coil 41a connected to the non-inverting input terminal of the amplifier AMP will also be referred to as the "second end."

[0023] Coil 51a is disposed above coil 31a. One end of coil 51a is connected to one end of wiring 53a. The other end of coil 51a is connected to one end of wiring 54a. Hereinafter, of the two ends of coil 51a, the end connected to wiring 53a will also be referred to as the "first end," and the end connected to wiring 54a will also be referred to as the "second end."

[0024] Coil 52a is disposed above coil 41a. One end of coil 52a is connected to the other end of wiring 53a. The other end of coil 52a is connected to the other end of wiring 54a. Hereinafter, of the two ends of coil 52a, the end connected to wiring 53a will also be referred to as the "first end," and the end connected to wiring 54a will also be referred to as the "second end."

[0025] The receiving circuit 21a includes, for example, an amplifier AMP and a detection circuit DEC. The amplifier AMP amplifies the inverted signal S4ma received from one end of the coil 41a and transmits the amplified inverted signal S5ma to the detection circuit DEC. The amplifier AMP amplifies the non-inverted signal S4pa received from the other end of the coil 41a and transmits the amplified non-inverted signal S5pa to the detection circuit DEC.

[0026] The detector circuit DEC detects the non-inverted signal S5pa from the non-inverted signal S5pa and the inverted signal S5ma received from the amplifier AMP, and transmits the detected non-inverted signal S5pa to the electronic circuit 22a as a signal S6a.

[0027] The electronic circuit 22a includes, for example, a demodulation circuit, which demodulates the signal S6a received from the detection circuit DEC and outputs the demodulated signal as an output signal OUT1a to the outside via the external electrode terminal T2a.

[0028] The second transmission circuit TCb includes an external electrode terminal T1b, an electronic circuit 11b, a transmission circuit 12b, coils 31b, 41b, 51b, and 52b, wires 53b and 54b, a reception circuit 21b, an electronic circuit 22b, and an external electrode terminal T2b.

[0029] The external electrode terminals T1b and T2b correspond to the external electrode terminals T1a and T2a, respectively.

[0030] The electronic circuit 11b corresponds to the electronic circuit 11a and has the same configuration as the electronic circuit 11a.

[0031] The transmission circuit 12b corresponds to the transmission circuit 12a and has the same configuration as the transmission circuit 12a.

[0032] Coils 31b, 41b, 51b, and 52b correspond to coils 31a, 41a, 51a, and 52b, respectively.

[0033] The wires 53b and 54b correspond to the wires 53a and 54a, respectively.

[0034] The receiving circuit 21b corresponds to the receiving circuit 21a and has the same configuration as the receiving circuit 21a.

[0035] The electronic circuit 22b corresponds to the electronic circuit 22a and has the same configuration as the electronic circuit 22a.

[0036] Signals IN1b, S1b, S2pb, S2mb, S3pb, S3mb, S4pb, S4mb, S5pb, S5mb, S6b, and OUT1b correspond to signals IN1a, S1a, S2pa, S2ma, S3pa, S3ma, S4pa, S4ma, S5pa, S5ma, S6a, and OUT1a, respectively.

[0037] The currents I1b, I2b, and I3b correspond to the currents I1a, I2a, and I3a, respectively.

[0038] The magnetic fields H1b and H2b correspond to the magnetic fields H1a and H2a, respectively.

[0039] The connections between the components of the second transmission circuit TCb are similar to the connections between the components of the first transmission circuit TCa.

[0040] 1.2 Isolator structure The structure of the isolator 1 will be described.

[0041] (Planar structure) FIG. 2 is a plan view showing an example of the planar structure of the isolator 1. As shown in FIG.

[0042] In addition to the components shown in FIG. 1 , isolator 1 includes printed wiring boards (hereinafter referred to as “wiring boards”) 30, 40, and 50, conductors 60a and 60b, attachment materials 61a and 61b, wiring 62a and 62b, pads 63a and 63b, wiring 64a, 64b, 65a, and 65b, pads 66a and 66b, wiring 67a and 67b, vias 68a and 68b, conductors 80a and 80b, attachment materials 81a and 81b, wiring 82a and 82b, pads 83a and 83b, wiring 84a, 84b, 85a, and 85b, pads 86a and 86b, wiring 87a and 87b, vias 88a and 88b, insulator 100, and resin 110. In addition, in Figure 2, the external electrode terminals T1a, T1b, T2a, and T2b, the wiring board 50, the coils 51a, 51b, 52a, and 52b, the wiring 53a, 53b, 54a, and 54b, the vias 68a, 68b, 88a, and 88b, the insulator 100, and the resin 110 are omitted.

[0043] In the following description, the direction substantially parallel to the surface of wiring board 30, from coil 31a toward coil 41a, is defined as the X direction. The direction substantially parallel to the surface of wiring board 30, from coil 31a toward coil 31b, is defined as the Y direction. The direction substantially perpendicular to the surface of wiring board 30, from coil 31a toward coil 51a, is defined as the Z direction.

[0044] As shown in FIG. 2, the wiring board 30 is, for example, a flexible printed circuit (FPC). The wiring board 30 is made of, for example, an FPC material. The wiring board 30 has, for example, a plate-like shape. The wiring board 30 includes a first surface and a second surface aligned in the Z direction. The second surface faces the first surface. Hereinafter, the surface of the wiring board 30 on which the chip 10 is provided will be referred to as the "first surface P1," and the surface of the wiring board 30 on which the chip 10 is not provided will be referred to as the "second surface P2." The wiring board 30 may be made of, for example, a glass epoxy material or a Teflon (registered trademark) material. The thickness of the wiring board 30 is, for example, approximately 25 μm.

[0045] The coils 31a and 31b are provided on the first surface P1 of the wiring board 30. The coils 31a and 31b include, for example, a conductor wound in a spiral shape along the XY plane. The coils 31a and 31b are, for example, circular in shape. The coils 31a and 31b include, for example, copper. The thickness of the coils 31a and 31b is, for example, not less than 6 μm and not more than 12 μm. The shape of the coils 31a and 31b may be rectangular or polygonal.

[0046] The conductors 60a and 60b are, for example, members for mounting the chip 10. The conductors 60a and 60b are provided on the first surface P1 of the wiring board 30. The conductors 60a and 60b have, for example, a plate shape. The conductors 60a and 60b are made of, for example, a conductive material. The conductors 60a and 60b are, for example, copper foil.

[0047] The attachment material 61a is provided on the conductor 60a. The attachment material 61b is provided on the conductor 60b. The attachment materials 61a and 61b are made of, for example, a conductive material. The attachment materials 61a and 61b are, for example, silver paste.

[0048] The chip 10 is provided on the attachment materials 61a and 61b. The chip 10 includes pads 13a, 13b, 14a, 14b, 15a, and 15b. The pads 13a, 13b, 14a, 14b, 15a, and 15b are, for example, electrode pads. The pads 13a, 13b, 14a, and 14b are provided on the upper surface of the chip 10. The pads 15a and 15b are provided on the lower surface of the chip 10. The pad 13a is used to connect the transmitting circuit 12a to the pad 63a. The pad 13b is used to connect the transmitting circuit 12b to the pad 63b. The pad 14a is used to connect the transmitting circuit 12a to the pad 66a. The pad 14b is used to connect the transmitting circuit 12b to the pad 66b. The pad 15a is used to connect the electronic circuit 11a to the attachment material 61a. The pad 15b is used to connect the electronic circuit 11b and the attachment material 61b. The pads 13a, 13b, 14a, 14b, 15a, and 15b are made of, for example, a conductive material.

[0049] The wiring 62a and 62b are, for example, bonding wires. One end of the wiring 62a is connected to the pad 13a. The other end of the wiring 62a is connected to the pad 63a. One end of the wiring 62b is connected to the pad 13b. The other end of the wiring 62b is connected to the pad 63b. The wiring 62a electrically connects the pad 13a and the pad 63a. The wiring 62b electrically connects the pad 13b and the pad 63b. The wiring 62a and 62b are made of, for example, a conductive material.

[0050] Pads 63a and 63b are, for example, electrode pads. Pads 63a and 63b are provided on first surface P1 of wiring board 30. Pad 63a is used to connect pad 13a to coil 31a. Pad 63b is used to connect pad 13b to coil 31b. Pads 63a and 63b are made of, for example, a conductive material.

[0051] Wiring 64a and 64b are provided on the first surface P1 of wiring board 30. One end of wiring 64a is connected to pad 63a. The other end of wiring 64a is connected to a first end of coil 31a. One end of wiring 64b is connected to pad 63b. The other end of wiring 64b is connected to a first end of coil 31b. Wiring 64a electrically connects pad 63a and the first end of coil 31a. Wiring 64b electrically connects pad 63b and the first end of coil 31b. Wiring 64a and 64b are made of, for example, a conductive material.

[0052] The wiring 65a and 65b are, for example, bonding wires. One end of the wiring 65a is connected to the pad 14a. The other end of the wiring 65a is connected to the pad 66a. One end of the wiring 65b is connected to the pad 14b. The other end of the wiring 65b is connected to the pad 66b. The wiring 65a electrically connects the pad 14a and the pad 66a. The wiring 65b electrically connects the pad 14b and the pad 66b. The wiring 65a and 65b are made of, for example, a conductive material.

[0053] Pads 66a and 66b are, for example, electrode pads. Pads 66a and 66b are provided on first surface P1 of wiring board 30. Pad 66a is used to connect pad 14a to coil 31a. Pad 66b is used to connect pad 14b to coil 31b. Pads 66a and 66b are made of, for example, a conductive material.

[0054] Wiring 67a and 67b are provided on the first surface P1 of wiring board 30. One end of wiring 67a is connected to pad 66a. The other end of wiring 67a is connected to the second end of coil 31a. One end of wiring 67b is connected to pad 66b. The other end of wiring 67b is connected to the second end of coil 31b. Wiring 67a electrically connects pad 66a and the second end of coil 31a. Wiring 67b electrically connects pad 66b and the second end of coil 31b. Wiring 67a and 67b are made of, for example, a conductive material.

[0055] The wiring board 40 is, for example, an FPC. The wiring board 40 is made of, for example, an FPC material. The wiring board 40 has, for example, a plate shape. The wiring board 40 is disposed apart from the wiring board 30 in the X direction via an insulator 100 (not shown). The wiring board 40 includes a third surface and a fourth surface aligned in the Z direction. The fourth surface faces the third surface. Hereinafter, the surface of the wiring board 40 on which the chip 20 is provided will be referred to as the "third surface P3," and the surface of the wiring board 40 on which the chip 20 is not provided will be referred to as the "fourth surface P4." The wiring board 40 may be made of, for example, a glass epoxy material or a Teflon material. The thickness of the wiring board 40 is, for example, approximately 25 μm.

[0056] The coils 41a and 41b are provided on the third surface P3 of the wiring board 40. The coils 41a and 41b include, for example, a conductor wound in a spiral shape along the XY plane. The coils 41a and 41b are, for example, circular in shape. The coils 41a and 41b include, for example, copper. The thickness of the coils 41a and 41b is, for example, not less than 6 μm and not more than 12 μm. The shape of the coils 41a and 41b may be rectangular or polygonal.

[0057] The conductors 80a and 80b are, for example, members on which the chip 20 is mounted. The conductors 80a and 80b are provided on the third surface P3 of the wiring board 40. The conductors 80a and 80b have, for example, a plate shape. The conductors 80a and 80b are made of, for example, a conductive material. The conductors 80a and 80b are, for example, copper foil.

[0058] The attachment material 81a is provided on the conductor 80a. The attachment material 81b is provided on the conductor 80b. The attachment materials 81a and 81b are made of, for example, a conductive material. The attachment materials 81a and 81b are, for example, silver paste.

[0059] The chip 20 is provided on the attachment materials 81a and 81b. The chip 20 includes pads 23a, 23b, 24a, 24b, 25a, and 25b. The pads 23a, 23b, 24a, 24b, 25a, and 25b are, for example, electrode pads. The pads 23a, 23b, 24a, and 24b are provided on the upper surface of the chip 20. The pads 25a and 25b are provided on the lower surface of the chip 20. The pad 23a is used to connect the receiving circuit 21a to the pad 83a. The pad 23b is used to connect the receiving circuit 21b to the pad 83b. The pad 24a is used to connect the receiving circuit 21a to the pad 86a. The pad 24b is used to connect the receiving circuit 21b to the pad 86b. The pad 25a is used to connect the electronic circuit 22a to the attachment material 81a. The pad 25b is used to connect the electronic circuit 22b and the attachment material 81b. The pads 23a, 23b, 24a, 24b, 25a, and 25b are made of, for example, a conductive material.

[0060] The wiring 82a and 82b are, for example, bonding wires. One end of the wiring 82a is connected to the pad 23a. The other end of the wiring 82a is connected to the pad 83a. One end of the wiring 82b is connected to the pad 23b. The other end of the wiring 82b is connected to the pad 83b. The wiring 82a electrically connects the pad 23a and the pad 83a. The wiring 82b electrically connects the pad 23b and the pad 83b. The wiring 82a and 82b are made of, for example, a conductive material.

[0061] Pads 83a and 83b are, for example, electrode pads. Pads 83a and 83b are provided on third surface P3 of wiring board 40. Pad 83a is used to connect pad 23a to coil 41a. Pad 83b is used to connect pad 23b to coil 41b. Pads 83a and 83b are made of, for example, a conductive material.

[0062] Wiring 84a and 84b are provided on third surface P3 of wiring board 40. One end of wiring 84a is connected to pad 83a. The other end of wiring 84a is connected to a first end of coil 41a. One end of wiring 84b is connected to pad 83b. The other end of wiring 84b is connected to a first end of coil 41b. Wiring 84a electrically connects pad 83a and the first end of coil 41a. Wiring 84b electrically connects pad 83b and the first end of coil 41b. Wiring 84a and 84b are made of, for example, a conductive material.

[0063] The wiring 85a and 85b are, for example, bonding wires. One end of the wiring 85a is connected to the pad 24a. The other end of the wiring 85a is connected to the pad 86a. One end of the wiring 85b is connected to the pad 24b. The other end of the wiring 85b is connected to the pad 86b. The wiring 85a electrically connects the pad 24a and the pad 86a. The wiring 85b electrically connects the pad 24b and the pad 86b. The wiring 85a and 85b are made of, for example, a conductive material.

[0064] Pads 86a and 86b are, for example, electrode pads. Pads 86a and 86b are provided on third surface P3 of wiring board 40. Pad 86a is used to connect pad 24a to coil 41a. Pad 86b is used to connect pad 24b to coil 41b. Pads 86a and 86b are made of, for example, a conductive material.

[0065] Wiring 87a and 87b are provided on third surface P3 of wiring board 40. One end of wiring 87a is connected to pad 86a. The other end of wiring 87a is connected to the second end of coil 41a. One end of wiring 87b is connected to pad 86b. The other end of wiring 87b is connected to the second end of coil 41b. Wiring 87a electrically connects pad 86a and the second end of coil 41a. Wiring 87b electrically connects pad 86b and the second end of coil 41b. Wiring 87a and 87b are made of, for example, a conductive material.

[0066] Fig. 3 is a plan view showing an example of the planar structure of the isolator 1. Note that in Fig. 3, the external electrode terminals T1a, T1b, T2a, and T2b, the coils 31a, 31b, 41a, and 41b, the vias 68a, 68b, 88a, and 88b, the insulator 100, and the resin 110 are omitted.

[0067] As shown in FIG. 3 , the wiring board 50 is, for example, an FPC. The wiring board 50 is made of, for example, an FPC material. The wiring board 50 has, for example, a plate shape. The wiring board 50 is disposed spaced apart from the wiring boards 30 and 40 in the Z direction via an insulator 100 (not shown). The wiring board 50 includes a fifth surface and a sixth surface aligned in the Z direction. The sixth surface faces the fifth surface. The sixth surface faces the first surface P1 of the wiring board 30 and the third surface P3 of the wiring board 40. Hereinafter, the surface of the wiring board 50 opposite the wiring boards 30 and 40 will be referred to as the “fifth surface P5,” and the surface of the wiring board 50 facing the wiring boards 30 and 40 will be referred to as the “sixth surface P6.” The wiring board 50 may be made of, for example, a glass epoxy material or a Teflon material. The thickness of the wiring board 50 is, for example, approximately 25 μm.

[0068] Coils 51a, 51b, 52a, and 52b are provided on a sixth surface P6 of wiring board 50. Coil 51a faces coil 31a. Coil 51b faces coil 31b. Coil 52a faces coil 41a. Coil 52b faces coil 41b. Coils 51a, 51b, 52a, and 52b include, for example, a conductor wound in a spiral shape along the XY plane. Coils 51a, 51b, 52a, and 52b are, for example, circular in shape. Coils 51a, 51b, 52a, and 52b include, for example, copper. Coils 51a, 51b, 52a, and 52b have a thickness of, for example, 6 μm or more and 12 μm or less. Coils 51a, 51b, 52a, and 52b may be rectangular or polygonal in shape.

[0069] The wiring 53a and 53b are provided on the sixth surface P6 of the wiring board 50. One end of the wiring 53a is connected to a first end of the coil 51a. The other end of the wiring 53a is connected to a first end of the coil 52a. One end of the wiring 53b is connected to a first end of the coil 51b. The other end of the wiring 53b is connected to a first end of the coil 52b. The wiring 53a electrically connects the first end of the coil 51a and the first end of the coil 52a. The wiring 53b electrically connects the first end of the coil 51b and the first end of the coil 52b. The wiring 53a and 53b are made of, for example, a conductive material.

[0070] The wiring 54a and 54b are, for example, bonding wires. One end of the wiring 54a is connected to the second end of the coil 51a. The other end of the wiring 54a is connected to the second end of the coil 52a. One end of the wiring 54b is connected to the second end of the coil 51b. The other end of the wiring 54b is connected to the second end of the coil 52b. The wiring 54a electrically connects the second end of the coil 51a and the second end of the coil 52a. The wiring 54b electrically connects the second end of the coil 51b and the second end of the coil 52b. The wiring 54a and 54b are made of, for example, a conductive material.

[0071] The coil 52a is electrically connected to the coil 51a via the wires 53a and 54a, and the coil 52b is electrically connected to the coil 51b via the wires 53b and 54b.

[0072] 4 is a plan view showing an example of the planar structure of isolator 1. FIG. 4 is a plan view of isolator 1 as seen from the second surface P2 side of wiring board 30 and the fourth surface P4 side of wiring board 40. In Figure 4, chips 10 and 20, coils 31a, 31b, 41a, and 41b, wiring board 50, coils 51a, 51b, 52a, and 52b, wiring 53a, 53b, 54a, and 54b, attachment materials 61a and 61b, wiring 62a and 62b, pads 63a and 63b, wiring 64a, 64b, 65a, 65b, pads 66a and 66b, wiring 67a and 67b, attachment materials 81a and 81b, wiring 82a and 82b, pads 83a and 83b, wiring 84a, 84b, 85a, and 85b, pads 86a and 86b, wiring 87a and 87b, insulator 100, and resin 110 are omitted.

[0073] 4, the external electrode terminals T1a and T1b are provided on the second surface P2 of the wiring board 30. The external electrode terminals T1a and T1b are made of, for example, a conductive material, such as copper foil.

[0074] The vias 68a and 68b are, for example, through vias. The vias 68a and 68b penetrate the wiring board 30. One end of the via 68a is connected to the conductor 60a. The other end of the via 68a is connected to the external electrode terminal T1a. One end of the via 68b is connected to the conductor 60b. The other end of the via 68b is connected to the external electrode terminal T1b. The via 68a electrically connects the conductor 60a and the external electrode terminal T1a. The via 68b electrically connects the conductor 60b and the external electrode terminal T1b. The vias 68a and 68b are, for example, made of a conductive material. The vias 68a and 68b are, for example, copper foil.

[0075] The external electrode terminals T2a and T2b are provided on the fourth surface P4 of the wiring board 40. The external electrode terminals T2a and T2b are made of, for example, a conductive material, such as copper foil.

[0076] The vias 88a and 88b are, for example, through vias. The vias 88a and 88b penetrate the wiring board 40. One end of the via 88a is connected to the conductor 80a. The other end of the via 88a is connected to the external electrode terminal T2a. One end of the via 88b is connected to the conductor 80b. The other end of the via 88b is connected to the external electrode terminal T2b. The via 88a electrically connects the conductor 80a and the external electrode terminal T2a. The via 88b electrically connects the conductor 80b and the external electrode terminal T2b. The vias 88a and 88b are, for example, made of a conductive material. The vias 88a and 88b are, for example, copper foil.

[0077] The power supply voltage terminal T3 is provided on the second surface P2 of the wiring board 30. A power supply voltage VDD is supplied to the chip 10 via the power supply voltage terminal T3. The power supply voltage terminal T3 is made of, for example, a conductive material.

[0078] The ground voltage terminal T4 is provided on the second surface P2 of the wiring board 30. The ground voltage VSS is supplied to the chip 10 via the ground voltage terminal T4. The ground voltage terminal T4 is made of, for example, a conductive material.

[0079] The power supply voltage terminal T5 is provided on the fourth surface P4 of the wiring board 40. A power supply voltage VDD is supplied to the chip 20 via the power supply voltage terminal T5. The power supply voltage terminal T5 is made of, for example, a conductive material.

[0080] The ground voltage terminal T6 is provided on the fourth surface P4 of the wiring board 40. The ground voltage VSS is supplied to the chip 20 via the ground voltage terminal T6. The ground voltage terminal T6 is made of, for example, a conductive material.

[0081] (Cross-sectional structure) 5 is a cross-sectional view showing an example of the cross-sectional structure of the isolator 1. FIG. 5 is a cross-sectional view taken along line II in FIGS.

[0082] 5, a via 68a is provided in the wiring board 30. The via 68a extends in the Z direction and penetrates the wiring board 30.

[0083] An external electrode terminal T1a is provided on second surface P2 (the surface opposite to wiring board 50) of wiring board 30. External electrode terminal T1a contacts via 68a.

[0084] A coil 31a, a conductor 60a, a pad 63a, and a wiring 64a are provided on a first surface P1 (the surface facing the wiring board 50) of the wiring board 30. The conductor 60a is in contact with a via 68a. An attachment material 61a is provided on the conductor 60a. A chip 10 is provided on the attachment material 61a. A pad 15a of the chip 10 is in contact with the attachment material 61a. A pad 13a of the chip 10 is electrically connected to a first end of the coil 31a via the wiring 62a, the pad 63a, and the wiring 64a. In other words, the coil 31a is electrically connected to the chip 10. The pad 15a of the chip 10 is electrically connected to an external electrode terminal T1a via the attachment material 61a, the conductor 60a, and the via 68a.

[0085] The chip 10 is provided on a first surface P1 of the wiring board 30 facing in the Z direction.

[0086] A via 88a is provided in the wiring board 40. The via 88a extends in the Z direction and penetrates the wiring board 40.

[0087] An external electrode terminal T2a is provided on the fourth surface P4 (the surface opposite to wiring board 50) of wiring board 40. External electrode terminal T2a is in contact with via 88a.

[0088] A coil 41a, a conductor 80a, a pad 83a, and a wiring 84a are provided on the third surface P3 (the surface facing the wiring board 50) of the wiring board 40. The conductor 80a is in contact with the via 88a. An attachment material 81a is provided on the conductor 80a. The chip 20 is provided on the attachment material 81a. A pad 25a of the chip 20 is in contact with the attachment material 81a. The pad 23a of the chip 20 is electrically connected to the first end of the coil 41a via the wiring 82a, the pad 83a, and the wiring 84a. In other words, the coil 41a is electrically connected to the chip 20. The pad 25a of the chip 20 is electrically connected to the external electrode terminal T2a via the attachment material 81a, the conductor 80a, and the via 88a.

[0089] Chip 20 is provided on third surface P3 of wiring board 40 facing in the Z direction.

[0090] Coils 51a and 52a and a wire 53a are provided on a sixth surface P6 of the wiring board 50.

[0091] A first end of the coil 51a is electrically connected to a first end of the coil 52a via a wire 53a.

[0092] Insulators 100 are provided between wiring board 30 and wiring board 40, between wiring board 30 and wiring board 50, and between wiring board 40 and wiring board 50. In other words, insulator 100 is provided between coil 31a and coil 41a. Insulator 100 is provided between coil 31a and coil 51a. Insulator 100 is provided between coil 41a and coil 52a. Insulator 100 is provided between coil 51a and coil 52a. The distance between coil 31a and coil 51a is determined by, for example, the magnetic coupling coefficient between coil 31a and coil 51a and the dielectric strength voltage of insulator 100. The distance between coil 41a and coil 52a is determined by, for example, the magnetic coupling coefficient between coil 41a and coil 52a and the dielectric strength voltage of insulator 100. This allows magnetic coupling between coil 31a and coil 51a, and between coil 41a and coil 52a, while coils 31a, 41a, 51a, and 52a are insulated from one another. Also, a portion of first surface P1 of wiring board 30 and the surface facing wiring board 40, a portion of third surface P3 of wiring board 40 and the surface facing wiring board 30, a portion of sixth surface P6 of wiring board 50, coils 31a, 41a, 51a, and 52a, wire 53a, a portion of wire 64a, and a portion of wire 84a are covered with insulator 100. Insulator 100 is made of, for example, an insulating material.

[0093] First surface P1 of wiring board 30, conductor 60a, attachment material 61a, chip 10, wiring 62a, pad 63a, wiring 64a, third surface P3 of wiring board 40, conductor 80a, attachment material 81a, chip 20, wiring 82a, pad 83a, wiring 84a, wiring board 50, and insulator 100 are covered with resin 110. Resin 110 is, for example, epoxy resin.

[0094] 6 is a cross-sectional view showing an example of the cross-sectional structure of the isolator 1. FIG. 6 is a cross-sectional view taken along line II-II in FIGS.

[0095] 6, a pad 66a and a wiring 67a are provided on the first surface P1 of the wiring board 30. The pad 14a of the chip 10 is electrically connected to the second end of the coil 31a via the wiring 65a, the pad 66a, and the wiring 67a.

[0096] Pads 86a and wiring 87a are provided on the third surface P3 of wiring board 40. Pads 24a of chip 20 are electrically connected to the second end of coil 41a via wiring 85a, pads 86a, and wiring 87a.

[0097] The second end of the coil 51a is electrically connected to the second end of the coil 52a via a wire 54a.

[0098] The wiring 54a, a part of the wiring 67a, and a part of the wiring 87a are covered with an insulator 100.

[0099] The wiring 65a, the pad 66a, the wiring 67a, the wiring 85a, the pad 86a, and the wiring 87a are covered with resin 110.

[0100] The above structure is the cross-sectional structure of the first transmission circuit TCa of the isolator 1. The cross-sectional structure of the second transmission circuit TCb of the isolator 1 is the same as the cross-sectional structure of the first transmission circuit TCa.

[0101] 1.3 Isolator Operation The operation of the isolator 1 will be described with reference to Fig. 1. Below, the operation of the first transmission circuit TCa during signal transmission between the transmission circuit 12a and the reception circuit 21a will be described.

[0102] As shown in FIG. 1, when a non-inverted signal S3pa is input from the transmission circuit 12a to a first end of the coil 31a and an inverted signal S3ma is input from the transmission circuit 12a to a second end of the coil 31a, a current I1a flows through the coil 31a based on the signals S3pa and S3ma. The direction of the current I1a flowing through the coil 31a is, for example, from the first end to the second end of the coil 31a. As a result, an upward magnetic field H1a is generated in the coil 31a (from the coil 31a to the coil 51a). When the upward magnetic field H1a is generated in the coil 31a, the magnetic flux passing through the coil 51a changes. As a result, a current I2a (induced current) flows through the coil 51a. The direction of the current I2a flowing through the coil 51a is, for example, from the second end to the first end of the coil 51a.

[0103] When current I2a flows through coil 51a, current I2a also flows through coil 52a. The direction of current I2a flowing through coil 52a is, for example, from the first end to the second end of coil 52a. As a result, a magnetic field H2a is generated in coil 52a in the downward direction (from coil 52a to coil 41a). When the downward magnetic field H2a is generated in coil 52a, the magnetic flux passing through coil 41a changes. As a result, current I3a (induced current) flows through coil 41a. The direction of current I3a flowing through coil 41a is, for example, from the second end to the first end of coil 41a.

[0104] When the current I3a flows through the coil 41a, a non-inverted signal S4pa is input from the second terminal of the coil 41a to the receiving circuit 21a based on the current I3a, and an inverted signal S4ma is input from the first terminal of the coil 41a to the receiving circuit 21a.

[0105] In this way, the isolator 1 (first transmission circuit TCa) receives a signal (electrical signal) from the chip 10 (transmission circuit 12a) and converts the received signal into magnetic energy via the coil 31a. The isolator 1 then converts the magnetic energy back into a signal (electrical signal) via the coils 51a, 52a, and 41a and transmits the converted signal to the chip 20 (reception circuit 21a). In this way, the isolator 1 transmits a signal from the chip 10 to the chip 20 while maintaining insulation between the chips 10 and 20.

[0106] The operation of the second transmission circuit TCb in the isolator 1 is similar to the operation of the first transmission circuit TCa.

[0107] The isolator 1 of this embodiment allows the size of the semiconductor package to be reduced.

[0108] When a coil for magnetic coupling is provided on the semiconductor chip on the transmitting side and a coil for magnetic coupling is provided on the semiconductor chip on the receiving side, the size of each semiconductor chip becomes larger than when no coil is provided on each semiconductor chip. Therefore, when a semiconductor chip with a coil is placed in isolator 1, the size of isolator 1 may become larger than when a semiconductor chip without a coil is placed in isolator 1.

[0109] In contrast, in this embodiment, coils 31a and 31b are provided on the first surface P1 of wiring board 30. Coils 41a and 41b are provided on the third surface P3 of wiring board 40. Coils 51a, 51b, 52a, and 52b are provided on the sixth surface P6 of wiring board 50. Therefore, according to this embodiment, the size of chips 10 and 20 can be reduced compared to, for example, a case in which coils 31a, 31b, 51a, and 51b are provided on chip 10 and coils 41a, 41b, 52a, and 52b are provided on chip 20. Therefore, the cost of chips 10 and 20 can be reduced.

[0110] Furthermore, in this embodiment, relatively thin wiring boards 30, 40, and 50 are used as members for arranging chips, coils, wiring, etc. Therefore, according to this embodiment, the size of the isolator 1 can be reduced compared to when a lead frame is used as a member for arranging chips, coils, wiring, etc.

[0111] Furthermore, in this embodiment, external electrode terminals T1a and T1b are provided on the second surface P2 of wiring board 30. External electrode terminals T2a and T2b are provided on the fourth surface P4 of wiring board 40. Therefore, according to this embodiment, the upper and lower surfaces of the lead frame are covered with resin, and the size of isolator 1 can be reduced compared to when the lead frame is pulled out as external electrode terminals.

[0112] 1.4 First variant An isolator according to a first modification of the first embodiment will be described. The isolator 1 according to the first modification of the first embodiment differs from the first embodiment in that the coils 31a, 31b, 41a, 41b, 51a, 51b, 52a, and 52b are covered with resin. In the following explanation, the description of the same configuration as the first embodiment will be omitted, and the description will focus mainly on the configuration that differs from the first embodiment.

[0113] 1.4.1 Isolator structure The structure of the isolator 1 will be described.

[0114] The planar structure of the isolator 1 is the same as that shown in FIGS. 2 to 4 in the first embodiment.

[0115] 7 is a cross-sectional view showing an example of the cross-sectional structure of the isolator 1. FIG. 7 is a cross-sectional view taken along line II in FIGS.

[0116] As shown in Fig. 7, coil 31a is covered with resin 32a except for its first end connected to wiring 64a. Coil 41a is covered with resin 42a except for its first end connected to wiring 84a. Coil 51a is covered with resin 55a except for its first end connected to wiring 53a. Coil 52a is covered with resin 56a except for its first end connected to wiring 53a. Resins 32a, 42a, 55a, and 56a are, for example, polyimide resin.

[0117] The distance between coil 31a and coil 51a is determined by, for example, the magnetic coupling coefficient between coil 31a and coil 51a and the dielectric strength voltage between insulator 100 and resins 32a and 55a. The distance between coil 41a and coil 52a is determined by, for example, the magnetic coupling coefficient between coil 41a and coil 52a and the dielectric strength voltage between insulator 100 and resins 42a and 56a.

[0118] Resins 32a, 42a, 55a, and 56a are covered with insulator 100. In other words, resin 32a is provided between coil 31a and insulator 100. Resin 42a is provided between coil 41a and insulator 100. Resin 55a is provided between coil 51a and insulator 100. Resin 56a is provided between coil 52a and insulator 100.

[0119] Other parts of the cross-sectional structure of the isolator 1 shown in FIG. 7 are the same as those shown in FIG. 5 in the first embodiment.

[0120] 8 is a cross-sectional view showing an example of the cross-sectional structure of the isolator 1. FIG. 8 is a cross-sectional view taken along line II-II in FIGS.

[0121] 8, coil 31a is covered with resin 32a except for its second end connected to wiring 67a. Coil 41a is covered with resin 42a except for its second end connected to wiring 87a. Coil 51a is covered with resin 55a except for its second end connected to wiring 54a. Coil 52a is covered with resin 56a except for its second end connected to wiring 54a.

[0122] Other parts of the cross-sectional structure of the isolator 1 shown in FIG. 8 are the same as those shown in FIG. 6 in the first embodiment.

[0123] The above structure is the cross-sectional structure of the first transmission circuit TCa of the isolator 1. The cross-sectional structure of the second transmission circuit TCb of the isolator 1 is the same as the cross-sectional structure of the first transmission circuit TCa. That is, the coils 31b, 41b, 51b, and 52b are covered with resins 32b, 42b, 55b, and 56b (not shown).

[0124] In this modification, as in the first embodiment, coils 31a, 31b, 51a, and 51b are not provided on chip 10, and coils 41a, 41b, 52a, and 52b are not provided on chip 20. Also, in this modification, as in the first embodiment, wiring boards 30, 40, and 50 are used as components for arranging chips, coils, wiring, etc. Furthermore, in this modification, as in the first embodiment, external electrode terminals T1a and T1b are provided on the second surface P2 of wiring board 30, and external electrode terminals T2a and T2b are provided on the fourth surface P4 of wiring board 40. Therefore, according to this modification, the size of the semiconductor package can be reduced.

[0125] 1.5 Second variant An isolator according to a second modified example of the first embodiment will be described. Isolator 1 according to the second modified example of the first embodiment differs from the first embodiment in that coils 31a and 31b are provided in wiring board 30, coils 41a and 41b are provided in wiring board 40, and coils 51a, 51b, 52a, and 52b are provided in wiring board 50. In the following explanation, explanations of the same configuration as in the first embodiment will be omitted, and the explanation will focus mainly on the configuration that differs from the first embodiment.

[0126] 1.5.1 Isolator structure The structure of the isolator 1 will be described.

[0127] (Planar structure) FIG. 9 is a plan view showing an example of the planar structure of the isolator 1. As shown in FIG.

[0128] The isolator 1 includes wirings 69a, 69b, 70a, 70b, 89a, 89b, 90a, and 90b in addition to the components shown in the first embodiment. Note that external electrode terminals T1a, T1b, T2a, and T2b, wiring board 50, coils 51a, 51b, 52a, and 52b, wirings 53a, 53b, 54a, and 54b, vias 68a, 68b, 88a, and 88b, insulator 100, and resin 110 are omitted from Fig. 9.

[0129] As shown in FIG. 9, the coils 31a and 31b and the wires 64a, 64b, 67a, 67b, 69a, 69b, 70a, and 70b are provided inside the wiring board 30.

[0130] One end of wire 64a is connected to one end of wire 69a. The other end of wire 64a is connected to a first end of coil 31a. One end of wire 64b is connected to one end of wire 69b. The other end of wire 64b is connected to a first end of coil 31b.

[0131] One end of the wiring 67a is connected to one end of the wiring 70a. The other end of the wiring 67a is connected to the second end of the coil 31a. One end of the wiring 67b is connected to one end of the wiring 70b. The other end of the wiring 67b is connected to the second end of the coil 31b.

[0132] The other end of the wiring 69a is connected to the pad 63a. The other end of the wiring 69b is connected to the pad 63b. The wiring 69a electrically connects the pad 63a and the first end of the coil 31a via the wiring 64a. The wiring 69b electrically connects the pad 63b and the first end of the coil 31b via the wiring 64b. The wirings 69a and 69b are made of, for example, a conductive material.

[0133] The other end of the wiring 70a is connected to the pad 66a. The other end of the wiring 70b is connected to the pad 66b. The wiring 70a electrically connects the pad 66a and the second end of the coil 31a via the wiring 67a. The wiring 70b electrically connects the pad 66b and the second end of the coil 31b via the wiring 67b. The wirings 70a and 70b are made of, for example, a conductive material.

[0134] The coils 41a and 41b and the wires 84a, 84b, 87a, 87b, 89a, 89b, 90a, and 90b are provided inside the wiring board 40.

[0135] One end of wire 84a is connected to one end of wire 89a. The other end of wire 84a is connected to a first end of coil 41a. One end of wire 84b is connected to one end of wire 89b. The other end of wire 84b is connected to a first end of coil 41b.

[0136] One end of wire 87a is connected to one end of wire 90a. The other end of wire 87a is connected to a second end of coil 41a. One end of wire 87b is connected to one end of wire 90b. The other end of wire 87b is connected to a second end of coil 41b.

[0137] The other end of the wiring 89a is connected to the pad 83a. The other end of the wiring 89b is connected to the pad 83b. The wiring 89a electrically connects the pad 83a and the first end of the coil 41a via the wiring 84a. The wiring 89b electrically connects the pad 83b and the first end of the coil 41b via the wiring 84b. The wirings 89a and 89b are made of, for example, a conductive material.

[0138] The other end of the wiring 90a is connected to pad 86a. The other end of the wiring 90b is connected to pad 86b. The wiring 90a electrically connects the pad 86a and the second end of the coil 41a via the wiring 87a. The wiring 90b electrically connects the pad 86b and the second end of the coil 41b via the wiring 87b. The wirings 90a and 90b are made of, for example, a conductive material.

[0139] Other parts of the planar structure of the isolator 1 shown in FIG. 9 are the same as those shown in FIG. 2 in the first embodiment.

[0140] Fig. 10 is a plan view showing an example of the planar structure of the isolator 1. Note that in Fig. 10, the external electrode terminals T1a, T1b, T2a, and T2b, the coils 31a, 31b, 41a, and 41b, the vias 68a, 68b, 88a, and 88b, the insulator 100, and the resin 110 are omitted.

[0141] As shown in FIG. 10, coils 51a, 51b, 52a, and 52b and wires 53a, 53b, 54a, and 54b are provided inside a wiring board 50.

[0142] Other parts of the planar structure of the isolator 1 shown in FIG. 10 are the same as those shown in FIG. 3 in the first embodiment.

[0143] The planar structure of isolator 1 viewed from second surface P2 side of wiring board 30 and fourth surface P4 side of wiring board 40 is the same as that shown in FIG. 4 in the first embodiment.

[0144] (Cross-sectional structure) 11 is a cross-sectional view showing an example of the cross-sectional structure of the isolator 1. FIG. 11 is a cross-sectional view taken along line II in FIGS.

[0145] As shown in FIG. 11, the wiring board 30 includes a coil 31a and wires 64a and 69a.

[0146] One end of the wire 69a contacts one end of the wire 64a, the other end of the wire 69a contacts the pad 63a, and the other end of the wire 64a contacts the first end of the coil 31a.

[0147] Within the wiring board 40, a coil 41a and wires 84a and 89a are provided.

[0148] One end of the wire 89a contacts one end of the wire 84a, the other end of the wire 89a contacts the pad 83a, and the other end of the wire 84a contacts the first end of the coil 41a.

[0149] Coils 51a and 52a and a wire 53a are provided within the wiring board 50.

[0150] One end of the wire 53a contacts the first end of the coil 51a, and the other end of the wire 53a contacts the first end of the coil 52a.

[0151] The distance between coil 31a and coil 51a is determined by, for example, the magnetic coupling coefficient between coil 31a and coil 51a and the dielectric strength voltage between insulator 100 and wiring board 30. The distance between coil 41a and coil 52a is determined by, for example, the magnetic coupling coefficient between coil 41a and coil 52a and the dielectric strength voltage between insulator 100 and wiring board 40.

[0152] A part of first surface P1 of wiring board 30 and the surface facing wiring board 40, a part of third surface P3 of wiring board 40 and the surface facing wiring board 30, and a sixth surface P6 of wiring board 50 are covered with insulator 100.

[0153] The first surface P1 of the wiring board 30, the conductor 60a, the attachment material 61a, the chip 10, the wiring 62a, the pad 63a, the third surface P3 of the wiring board 40, the conductor 80a, the attachment material 81a, the chip 20, the wiring 82a, the pad 83a, the wiring board 50, and the insulator 100 are covered with resin 110.

[0154] Other parts of the cross-sectional structure of the isolator 1 shown in FIG. 11 are the same as those shown in FIG. 5 in the first embodiment.

[0155] 12 is a cross-sectional view showing an example of the cross-sectional structure of the isolator 1. FIG. 12 is a cross-sectional view taken along line II-II in FIGS.

[0156] As shown in FIG. 12, wiring board 30 includes wirings 67a and 70a.

[0157] One end of the wire 70a contacts one end of the wire 67a, the other end of the wire 70a contacts the pad 66a, and the other end of the wire 67a contacts the second end of the coil 31a.

[0158] Wiring board 40 includes wirings 87a and 90a.

[0159] One end of the wire 90a contacts one end of the wire 87a, the other end of the wire 90a contacts the pad 86a, and the other end of the wire 87a contacts the second end of the coil 41a.

[0160] Wiring 54a is provided within wiring board 50.

[0161] One end of the wire 54a contacts the second end of the coil 51a, and the other end of the wire 54a contacts the second end of the coil 52a.

[0162] Other parts of the cross-sectional structure of the isolator 1 shown in FIG. 12 are the same as those shown in FIG. 6 in the first embodiment.

[0163] The above structure is the cross-sectional structure of the first transmission circuit TCa of the isolator 1. The cross-sectional structure of the second transmission circuit TCb of the isolator 1 is the same as the cross-sectional structure of the first transmission circuit TCa.

[0164] In this modification, coils 31a and 31b are provided within wiring board 30. Coils 41a and 41b are provided within wiring board 40. Coils 51a, 51b, 52a, and 52b are provided within wiring board 50. That is, in this modification, as in the first embodiment, coils 31a, 31b, 51a, and 51b are not provided on chip 10, and coils 41a, 41b, 52a, and 52b are not provided on chip 20. Also, in this modification, as in the first embodiment, wiring boards 30, 40, and 50 are used as components for arranging chips, coils, wiring, and the like. Furthermore, in this modification, as in the first embodiment, external electrode terminals T1a and T1b are provided on the second surface P2 of wiring board 30, and external electrode terminals T2a and T2b are provided on the fourth surface P4 of wiring board 40. Therefore, according to this modification, the size of the semiconductor package can be reduced.

[0165] 2. Second embodiment An isolator according to a second embodiment will be described. The internal structure of the isolator 1 according to the second embodiment is different from that of the first embodiment. In the following explanation, the description of the same configuration as that of the first embodiment will be omitted, and the configuration different from that of the first embodiment will be mainly explained.

[0166] 2.1 Isolator structure The structure of the isolator 1 will be described.

[0167] (Planar structure) FIG. 13 is a plan view showing an example of the planar structure of the isolator 1. As shown in FIG.

[0168] In addition to the components shown in the first embodiment, the isolator 1 includes conductors 71a and 71b, bumps 72a and 72b, conductors 73a and 73b, bumps 74a and 74b, conductors 75a and 75b, bumps 76a and 76b, conductors 91a and 91b, bumps 92a and 92b, conductors 93a and 93b, bumps 94a and 94b, conductors 95a and 95b, and bumps 96a and 96b. 13 , the conductors 60a and 60b, the attachment materials 61a and 61b, the wirings 62a and 62b, the pads 63a and 63b, the wirings 65a and 65b, the pads 66a and 66b, the conductors 80a and 80b, the attachment materials 81a and 81b, the wirings 82a and 82b, the pads 83a and 83b, the wirings 85a and 85b, and the pads 86a and 86b are omitted. Note that, in FIG. 13 , the external electrode terminals T1a, T1b, T2a, and T2b, the wiring board 50, the coils 51a, 51b, 52a, and 52b, the wirings 53a, 53b, 54a, and 54b, the vias 68a, 68b, 88a, and 88b, the insulator 100, and the resin 110 are omitted.

[0169] As shown in FIG. 13, the conductors 71a, 71b, 73a, 73b, 75a, and 75b are, for example, members for mounting the chip 10. The conductors 71a, 71b, 73a, 73b, 75a, and 75b are provided on the first surface P1 of the wiring board 30. The conductors 71a, 71b, 73a, 73b, 75a, and 75b have, for example, a plate shape. The conductors 71a, 71b, 73a, 73b, 75a, and 75b are, for example, made of a conductive material. The conductors 71a, 71b, 73a, 73b, 75a, and 75b are, for example, copper foil.

[0170] Bump 72a is provided on conductor 71a. Bump 72b is provided on conductor 71b. Bump 74a is provided on conductor 73a. Bump 74b is provided on conductor 73b. Bump 76a is provided on conductor 75a. Bump 76b is provided on conductor 75b. Bumps 72a, 72b, 74a, 74b, 76a, and 76b are made of, for example, a conductive material. Bumps 72a, 72b, 74a, 74b, 76a, and 76b are made of, for example, solder.

[0171] The chip 10 is provided on the bumps 72a, 72b, 74a, 74b, 76a, and 76b. Pads 13a, 13b, 14a, 14b, 15a, and 15b are provided on the underside of the chip 10. The pad 13a is used to connect the transmitting circuit 12a to the bump 72a. The pad 13b is used to connect the transmitting circuit 12b to the bump 72b. The pad 14a is used to connect the transmitting circuit 12a to the bump 76a. The pad 14b is used to connect the transmitting circuit 12b to the bump 76b. The pad 15a is used to connect the electronic circuit 11a to the bump 74a. The pad 15b is used to connect the electronic circuit 11b to the bump 74b.

[0172] One end of wiring 64a is connected to conductor 71a. The other end of wiring 64a is connected to a first end of coil 31a. One end of wiring 64b is connected to conductor 71b. The other end of wiring 64b is connected to a first end of coil 31b. Wiring 64a electrically connects conductor 71a and the first end of coil 31a. Wiring 64b electrically connects conductor 71b and the first end of coil 31b.

[0173] One end of wiring 67a is connected to conductor 75a. The other end of wiring 67a is connected to a second end of coil 31a. One end of wiring 67b is connected to conductor 75b. The other end of wiring 67b is connected to a second end of coil 31b. Wiring 67a electrically connects conductor 75a and the second end of coil 31a. Wiring 67b electrically connects conductor 75b and the second end of coil 31b.

[0174] The conductors 91a, 91b, 93a, 93b, 95a, and 95b are, for example, members for mounting the chip 20. The conductors 91a, 91b, 93a, 93b, 95a, and 95b are provided on the third surface P3 of the wiring board 40. The conductors 91a, 91b, 93a, 93b, 95a, and 95b have, for example, a plate shape. The conductors 91a, 91b, 93a, 93b, 95a, and 95b are, for example, made of a conductive material. The conductors 91a, 91b, 93a, 93b, 95a, and 95b are, for example, copper foil.

[0175] The bump 92a is provided on the conductor 91a. The bump 92b is provided on the conductor 91b. The bump 94a is provided on the conductor 93a. The bump 94b is provided on the conductor 93b. The bump 96a is provided on the conductor 95a. The bump 96b is provided on the conductor 95b. The bumps 92a, 92b, 94a, 94b, 96a, and 96b are made of, for example, a conductive material. The bumps 92a, 92b, 94a, 94b, 96a, and 96b are made of, for example, solder.

[0176] The chip 20 is provided on bumps 92a, 92b, 94a, 94b, 96a, and 96b. Pads 23a, 23b, 24a, 24b, 25a, and 25b are provided on the underside of the chip 20. Pad 23a is used to connect the receiving circuit 21a to the bump 92a. Pad 23b is used to connect the receiving circuit 21b to the bump 92b. Pad 24a is used to connect the receiving circuit 21a to the bump 96a. Pad 24b is used to connect the receiving circuit 21b to the bump 96b. Pad 25a is used to connect the electronic circuit 22a to the bump 94a. Pad 25b is used to connect the electronic circuit 22b to the bump 94b.

[0177] One end of wiring 84a is connected to conductor 91a. The other end of wiring 84a is connected to a first end of coil 41a. One end of wiring 84b is connected to conductor 91b. The other end of wiring 84b is connected to a first end of coil 41b. Wiring 84a electrically connects conductor 91a and the first end of coil 41a. Wiring 84b electrically connects conductor 91b and the first end of coil 41b.

[0178] One end of wiring 87a is connected to conductor 95a. The other end of wiring 87a is connected to a second end of coil 41a. One end of wiring 87b is connected to conductor 95b. The other end of wiring 87b is connected to a second end of coil 41b. Wiring 87a electrically connects conductor 95a and the second end of coil 41a. Wiring 87b electrically connects conductor 95b and the second end of coil 41b.

[0179] Fig. 14 is a plan view showing an example of the planar structure of the isolator 1. Note that in Fig. 14, the external electrode terminals T1a, T1b, T2a, and T2b, the coils 31a, 31b, 41a, and 41b, the vias 68a, 68b, 88a, and 88b, the insulator 100, and the resin 110 are omitted.

[0180] The wiring board 50, the coils 51a, 51b, 52a, and 52b, and the wires 53a, 53b, 54a, and 54b are the same as those shown in FIG. 3 in the first embodiment.

[0181] Fig. 15 is a plan view showing an example of the planar structure of isolator 1. Fig. 15 is a plan view of isolator 1 as seen from the second surface P2 side of wiring board 30 and the fourth surface P4 side of wiring board 40. In addition, in Figure 15, chips 10 and 20, coils 31a, 31b, 41a, and 41b, wiring board 50, coils 51a, 51b, 52a, and 52b, wiring 53a, 53b, 54a, and 54b, wiring 64a, 64b, 67a, and 67b, conductors 71a and 71b, bumps 72a and 72b, bumps 74a and 74b, conductors 75a and 75b, bumps 76a and 76b, wiring 84a, 84b, 87a, and 87b, conductors 91a and 91b, bumps 92a and 92b, bumps 94a and 94b, conductors 95a and 95b, bumps 96a and 96b, insulator 100, and resin 110 are omitted.

[0182] 15, one end of the via 68a is connected to the conductor 73a. The other end of the via 68a is connected to the external electrode terminal T1a. One end of the via 68b is connected to the conductor 73b. The other end of the via 68b is connected to the external electrode terminal T1b. The via 68a electrically connects the conductor 73a to the external electrode terminal T1a. The via 68b electrically connects the conductor 73b to the external electrode terminal T1b.

[0183] One end of the via 88a is connected to the conductor 93a. The other end of the via 88a is connected to the external electrode terminal T2a. One end of the via 88b is connected to the conductor 93b. The other end of the via 88b is connected to the external electrode terminal T2b. The via 88a electrically connects the conductor 93a and the external electrode terminal T2a. The via 88b electrically connects the conductor 93b and the external electrode terminal T2b.

[0184] Other parts of the cross-sectional structure of the isolator 1 shown in FIG. 15 are the same as those shown in FIG. 4 in the first embodiment.

[0185] (Cross-sectional structure) 16 is a cross-sectional view showing an example of the cross-sectional structure of the isolator 1. FIG. 16 is a cross-sectional view taken along line II in FIGS.

[0186] As shown in FIG. 16, conductors 71a and 73a are provided on the first surface P1 of the wiring board 30. The conductor 71a is in contact with one end of the wiring 64a. The conductor 73a is in contact with the via 68a. A bump 72a is provided on the conductor 71a. A bump 74a is provided on the conductor 73a. A chip 10 is provided on the bumps 72a and 74a. A pad 13a of the chip 10 is electrically connected to a first end of the coil 31a via the bump 72a, the conductor 71a, and the wiring 64a. A pad 15a of the chip 10 is electrically connected to the external electrode terminal T1a via the bump 74a, the conductor 73a, and the via 68a.

[0187] Conductors 91a and 93a are provided on the third surface P3 of the wiring board 40. The conductor 91a is in contact with one end of the wiring 84a. The conductor 93a is in contact with the via 88a. A bump 92a is provided on the conductor 91a. A bump 94a is provided on the conductor 93a. The chip 20 is provided on the bumps 92a and 94a. The pad 23a of the chip 20 is electrically connected to the first end of the coil 41a via the bump 92a, the conductor 91a, and the wiring 84a. The pad 25a of the chip 20 is electrically connected to the external electrode terminal T2a via the bump 94a, the conductor 93a, and the via 88a.

[0188] Other parts of the cross-sectional structure of the isolator 1 shown in FIG. 16 are similar to those shown in FIG. 5 in the first embodiment.

[0189] 17 is a cross-sectional view showing an example of the cross-sectional structure of the isolator 1. FIG. 17 is a cross-sectional view taken along line II-II in FIGS.

[0190] 17, a conductor 75a is provided on the first surface P1 of the wiring board 30. The conductor 75a is in contact with one end of the wiring 67a. A bump 76a is provided on the conductor 75a. The chip 10 is provided on the bump 76a. The pad 14a of the chip 10 is electrically connected to the second end of the coil 31a via the bump 76a, the conductor 75a, and the wiring 67a.

[0191] A conductor 95a is provided on the third surface P3 of the wiring board 40. The conductor 95a is in contact with one end of the wiring 87a. A bump 96a is provided on the conductor 95a. The chip 20 is provided on the bump 96a. The pad 24a of the chip 20 is electrically connected to the second end of the coil 41a via the bump 96a, the conductor 95a, and the wiring 87a.

[0192] Other parts of the cross-sectional structure of the isolator 1 shown in FIG. 17 are the same as those shown in FIG. 6 in the first embodiment.

[0193] The above structure is the cross-sectional structure of the first transmission circuit TCa of the isolator 1. The cross-sectional structure of the second transmission circuit TCb of the isolator 1 is the same as the cross-sectional structure of the first transmission circuit TCa.

[0194] According to this embodiment, the size of the semiconductor package can be reduced.

[0195] 2.2 First Modification A semiconductor device according to a first modification of the second embodiment will be described. The isolator 1 according to the first modification of the second embodiment differs from the second embodiment in that the coils 31a, 31b, 41a, 41b, 51a, 51b, 52a, and 52b are covered with resin. In the following explanation, the description of the same configuration as the second embodiment will be omitted, and the description will focus mainly on the configuration that differs from the second embodiment.

[0196] 2.2.1 Isolator structure The structure of the isolator 1 will be described.

[0197] The planar structure of the isolator 1 is the same as that shown in FIGS. 13 to 15 in the second embodiment.

[0198] 18 is a cross-sectional view showing an example of the cross-sectional structure of the isolator 1. FIG. 18 is a cross-sectional view taken along line II in FIGS.

[0199] 18, coil 31a is covered with resin 32a except for a first end connected to wiring 64a. Coil 41a is covered with resin 42a except for a first end connected to wiring 84a. Coil 51a is covered with resin 55a except for a first end connected to wiring 53a. Coil 52a is covered with resin 56a except for a first end connected to wiring 53a.

[0200] Resins 32a, 42a, 55a, and 56a are covered with insulator 100. In other words, resin 32a is provided between coil 31a and insulator 100. Resin 42a is provided between coil 41a and insulator 100. Resin 55a is provided between coil 51a and insulator 100. Resin 56a is provided between coil 52a and insulator 100.

[0201] Other parts of the cross-sectional structure of the isolator 1 shown in FIG. 18 are similar to those shown in FIG. 16 in the second embodiment.

[0202] 19 is a cross-sectional view showing an example of the cross-sectional structure of the isolator 1. FIG. 19 is a cross-sectional view taken along line II-II in FIGS.

[0203] 19, coil 31a is covered with resin 32a except for its second end connected to wiring 67a. Coil 41a is covered with resin 42a except for its second end connected to wiring 87a. Coil 51a is covered with resin 55a except for its second end connected to wiring 54a. Coil 52a is covered with resin 56a except for its second end connected to wiring 54a.

[0204] Other parts of the cross-sectional structure of the isolator 1 shown in FIG. 19 are similar to those shown in FIG. 17 in the first embodiment.

[0205] The above structure is the cross-sectional structure of the first transmission circuit TCa of the isolator 1. The cross-sectional structure of the second transmission circuit TCb of the isolator 1 is the same as the cross-sectional structure of the first transmission circuit TCa. That is, the coils 31b, 41b, 51b, and 52b are covered with resins 32b, 42b, 55b, and 56b (not shown).

[0206] According to this modification, the size of the semiconductor package can be reduced.

[0207] 2.3 Second variant A semiconductor device according to a second modification of the second embodiment will be described. Isolator 1 according to the second modification of the second embodiment differs from the second embodiment in that coils 31a and 31b are provided in wiring board 30, coils 41a and 41b are provided in wiring board 40, and coils 51a, 51b, 52a, and 52b are provided in wiring board 50. In the following explanation, explanations of the same configuration as in the second embodiment will be omitted, and the explanation will focus mainly on the configuration that differs from the second embodiment.

[0208] 2.3.1 Isolator structure The structure of the isolator 1 will be described.

[0209] (Planar structure) FIG. 20 is a plan view showing an example of the planar structure of the isolator 1. As shown in FIG.

[0210] The isolator 1 includes wirings 77a, 77b, 78a, 78b, 97a, 97b, 98a, and 98b in addition to the components shown in the second embodiment. Note that the external electrode terminals T1a, T1b, T2a, and T2b, the wiring board 50, the coils 51a, 51b, 52a, and 52b, the wirings 53a, 53b, 54a, and 54b, the vias 68a, 68b, 88a, and 88b, the insulator 100, and the resin 110 are omitted from Fig. 20 .

[0211] As shown in FIG. 20, coils 31a and 31b and wires 64a, 64b, 67a, 67b, 77a, 77b, 78a, and 78b are provided inside wiring board 30.

[0212] One end of wire 64a is connected to one end of wire 77a. The other end of wire 64a is connected to a first end of coil 31a. One end of wire 64b is connected to one end of wire 77b. The other end of wire 64b is connected to a first end of coil 31b.

[0213] One end of the wiring 67a is connected to one end of the wiring 78a. The other end of the wiring 67a is connected to the second end of the coil 31a. One end of the wiring 67b is connected to one end of the wiring 78b. The other end of the wiring 67b is connected to the second end of the coil 31b.

[0214] The other end of wiring 77a is connected to conductor 71a. The other end of wiring 77b is connected to conductor 71b. Wiring 77a electrically connects conductor 71a and a first end of coil 31a via wiring 64a. Wiring 77b electrically connects conductor 71b and a first end of coil 31b via wiring 64b. Wirings 77a and 77b are made of, for example, a conductive material.

[0215] The other end of wiring 78a is connected to conductor 75a. The other end of wiring 78b is connected to conductor 75b. Wiring 78a electrically connects conductor 75a and the second end of coil 31a via wiring 67a. Wiring 78b electrically connects conductor 75b and the second end of coil 31b via wiring 67b. Wirings 78a and 78b are made of, for example, a conductive material.

[0216] Coils 41a and 41b and wires 84a, 84b, 87a, 87b, 97a, 97b, 98a, and 98b are provided inside wiring board 40.

[0217] One end of wire 84a is connected to one end of wire 97a. The other end of wire 84a is connected to a first end of coil 41a. One end of wire 84b is connected to one end of wire 97b. The other end of wire 84b is connected to a first end of coil 41b.

[0218] One end of wire 87a is connected to one end of wire 98a. The other end of wire 87a is connected to a second end of coil 41a. One end of wire 87b is connected to one end of wire 98b. The other end of wire 87b is connected to a second end of coil 41b.

[0219] The other end of wiring 97a is connected to conductor 91a. The other end of wiring 97b is connected to conductor 91b. Wiring 97a electrically connects conductor 91a and a first end of coil 41a via wiring 84a. Wiring 97b electrically connects conductor 91b and a first end of coil 41b via wiring 84b. Wirings 97a and 97b are made of, for example, a conductive material.

[0220] The other end of wiring 98a is connected to conductor 95a. The other end of wiring 98b is connected to conductor 95b. Wiring 98a electrically connects conductor 95a and the second end of coil 41a via wiring 87a. Wiring 98b electrically connects conductor 95b and the second end of coil 41b via wiring 87b. Wiring 98a and 98b are made of, for example, a conductive material.

[0221] Other parts of the planar structure of the isolator 1 shown in FIG. 20 are similar to those shown in FIG. 13 in the second embodiment.

[0222] Fig. 21 is a plan view showing an example of the planar structure of the isolator 1. Note that in Fig. 21, the external electrode terminals T1a, T1b, T2a, and T2b, the coils 31a, 31b, 41a, and 41b, the vias 68a, 68b, 88a, and 88b, the insulator 100, and the resin 110 are omitted.

[0223] As shown in FIG. 21, coils 51a, 51b, 52a, and 52b and wires 53a, 53b, 54a, and 54b are provided inside a wiring board 50.

[0224] Other parts of the planar structure of the isolator 1 shown in FIG. 21 are similar to those shown in FIG. 14 in the second embodiment.

[0225] The planar structure of isolator 1 viewed from second surface P2 side of wiring board 30 and fourth surface P4 side of wiring board 40 is the same as that shown in FIG. 15 in the second embodiment.

[0226] (Cross-sectional structure) Fig. 22 is a cross-sectional view showing an example of the cross-sectional structure of the isolator 1. Fig. 22 is a cross-sectional view taken along line II in Figs.

[0227] As shown in FIG. 22, the wiring board 30 includes a coil 31a and wires 64a and 77a.

[0228] One end of the wire 77a contacts one end of the wire 64a, the other end of the wire 77a contacts the conductor 71a, and the other end of the wire 64a contacts the first end of the coil 31a.

[0229] Within the wiring board 40, a coil 41a and wires 84a and 97a are provided.

[0230] One end of the wire 97a contacts one end of the wire 84a, the other end of the wire 97a contacts the conductor 91a, and the other end of the wire 84a contacts the first end of the coil 41a.

[0231] Coils 51a and 52a and a wire 53a are provided within the wiring board 50.

[0232] One end of the wire 53a contacts the first end of the coil 51a, and the other end of the wire 53a contacts the first end of the coil 52a.

[0233] Other parts of the cross-sectional structure of the isolator 1 shown in FIG. 22 are similar to those shown in FIG. 16 in the second embodiment.

[0234] Fig. 23 is a cross-sectional view showing an example of the cross-sectional structure of the isolator 1. Fig. 23 is a cross-sectional view taken along line II-II in Figs.

[0235] As shown in FIG. 23, wiring board 30 includes wirings 67a and 78a.

[0236] One end of the wire 78a contacts one end of the wire 67a, the other end of the wire 78a contacts the conductor 75a, and the other end of the wire 67a contacts the second end of the coil 31a.

[0237] Wiring board 40 includes wiring 87a and 98a.

[0238] One end of the wire 98a contacts one end of the wire 87a, the other end of the wire 98a contacts the conductor 95a, and the other end of the wire 87a contacts the second end of the coil 41a.

[0239] Wiring 54a is provided within wiring board 50.

[0240] One end of the wire 54a contacts the second end of the coil 51a, and the other end of the wire 54a contacts the second end of the coil 52a.

[0241] Other parts of the cross-sectional structure of the isolator 1 shown in FIG. 23 are similar to those shown in FIG. 17 in the second embodiment.

[0242] The above structure is the cross-sectional structure of the first transmission circuit TCa of the isolator 1. The cross-sectional structure of the second transmission circuit TCb of the isolator 1 is the same as the cross-sectional structure of the first transmission circuit TCa.

[0243] According to this modification, the size of the semiconductor package can be reduced.

[0244] 3. Modifications, etc. As described above, the isolator (1) according to the embodiment includes a first semiconductor chip (10), a second semiconductor chip (20), a first wiring board (30) having the first semiconductor chip (10) provided on a first surface (P1) facing a first direction (Z), a second wiring board (40) having the second semiconductor chip (20) provided on a second surface (P3) facing the first direction (Z) and spaced apart from the first wiring board (30) in a second direction (X) intersecting the first direction (Z), a third wiring board (50) spaced apart from each of the first wiring board (30) and the second wiring board (40) in the first direction (Z), a first coil (31 a) provided on the first surface (P1) of the first wiring board (30) and electrically connected to the first semiconductor chip (10), and a second wiring board (40) provided on the second surface (P3) of the second wiring board (40), The semiconductor device includes a second coil (41a) electrically connected to the second semiconductor chip (20), a third coil (51a) provided on a third surface (P6) of the third wiring board (50) facing the first surface of the first wiring board (30) and the second surface of the second wiring board (40) and facing the first coil (31a), a fourth coil (52a) provided on the third surface (P6) of the third wiring board (50), facing the second coil (41a) and electrically connected to the third coil (51a), and insulators (100) provided between the first coil (31a) and the second coil (41a), between the first coil (31a) and the third coil (51a), between the second coil (41a) and the fourth coil (52a), and between the third coil (51a) and the fourth coil (52a).

[0245] The embodiment is not limited to the above-described embodiment, and various modifications are possible.

[0246] Although several embodiments of the present invention have been described, these embodiments are presented as examples and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included within the scope and spirit of the invention, as well as within the scope of the invention described in the claims and their equivalents. [Explanation of symbols]

[0247] 1...isolator, 10...semiconductor chip, 11a, 11b...electronic circuit, 12a, 12b...transmitting circuit, 13a, 13b, 14a, 14b, 15a, 15b...pad, 20...semiconductor chip, 21a, 21b...receiving circuit, 22a, 22b...electronic circuit, 23a, 23b, 24a, 24b, 25a, 25b...pad, 30...printed wiring board, 31a, 31b...coil, 32a, 32b...resin, 40...printed wiring board, 4 1a, 41b... Coil, 42a, 42b... Resin, 50... Printed wiring board, 51a, 51b, 52a, 52b... Coil, 53a, 53b, 54a, 54b... Wiring, 55a, 55b, 56a, 56b... Resin, 60a, 60b... Conductor, 61a, 61b... Attachment material, 62a, 62b... Wiring, 63a, 63b... Pad, 64a, 64b, 65a, 65b... Wiring, 66a, 66b... Pad, 67a, 67b... Wiring, 68 a, 68b... vias, 69a, 69b, 70a, 70b... wiring, 71a, 71b... conductors, 72a, 72b... bumps, 73a, 73b... conductors, 74a, 74b... bumps, 75a, 75b... conductors, 76a, 76b... bumps, 77a, 77b, 78a, 78b... wiring, 80a, 80b... conductors, 81a, 81b... attachment material, 82a, 82b... wiring, 83a, 83b... pads, 84a, 84b, 85a, 85b... Wiring, 86a, 86b...pads, 87a, 87b...wiring, 88a, 88b...vias, 89a, 89b, 90a, 90b...wiring, 91a, 91b...conductors, 92a, 92b...bumps, 93a, 93b...conductors, 94a, 94b...bumps, 95a, 95b...conductors, 96a, 96b...bumps, 97a, 97b, 98a, 98b...wiring, 100...insulator, 110...resin, T1a, T1b, T2a, T2b...external electrode terminals

Claims

1. a first semiconductor chip; a second semiconductor chip; a first wiring board having the first semiconductor chip provided on a first surface facing a first direction; a second wiring board having the second semiconductor chip provided on a second surface facing the first direction and spaced apart from the first wiring board in a second direction intersecting the first direction; a third wiring board spaced apart from each of the first wiring board and the second wiring board in the first direction; a first coil provided on the first surface of the first wiring board and electrically connected to the first semiconductor chip; a second coil provided on the second surface of the second wiring board and electrically connected to the second semiconductor chip; a third coil provided on a third surface of the third wiring board facing the first surface of the first wiring board and the second surface of the second wiring board, the third coil facing the first coil; a fourth coil provided on the third surface of the third wiring board, facing the second coil, and electrically connected to the third coil; insulators provided between the first coil and the second coil, between the first coil and the third coil, between the second coil and the fourth coil, and between the third coil and the fourth coil; Equipped with Isolator.

2. the first semiconductor chip includes a first pad and a second pad; the first pad is electrically connected to a first end of the first coil; the second pad is electrically connected to a second end of the first coil; the second semiconductor chip includes a third pad and a fourth pad; the third pad is electrically connected to a first end of the second coil; the fourth pad is electrically connected to a second end of the second coil; The isolator of claim 1 .

3. A first wire; A second wire; A third wire; The fourth wire and Further provided with the first pad is electrically connected to the first end of the first coil via the first wire; the second pad is electrically connected to the second end of the first coil via the second wire; the third pad is electrically connected to the first end of the second coil via the third wire; the fourth pad is electrically connected to the second end of the second coil via the fourth wire; The isolator of claim 2.

4. a first conductor and a second conductor provided on the first surface of the first wiring board; a third conductor and a fourth conductor provided on the second surface of the second wiring board; Further provided with the first pad is electrically connected to the first end of the first coil via the first conductor; the second pad is electrically connected to the second end of the first coil via the second conductor; the third pad is electrically connected to the first end of the second coil via the third conductor; the fourth pad is electrically connected to the second end of the second coil via the fourth conductor; The isolator of claim 2.

5. a first electrode terminal provided on a fourth surface of the first wiring board opposite to the first surface; a second electrode terminal provided on a fifth surface of the second wiring board facing the second surface; Further comprising: The isolator of claim 1 .

6. the first semiconductor chip includes a fifth pad; the fifth pad is electrically connected to the first electrode terminal, the second semiconductor chip includes a sixth pad; the sixth pad is electrically connected to the second electrode terminal; The isolator according to claim 5.

7. a first via extending in the first direction and penetrating the first wiring board; a second via extending in the first direction and penetrating the second wiring board; Further comprising: the fifth pad is electrically connected to the first electrode terminal through the first via; the sixth pad is electrically connected to the second electrode terminal through the second via; The isolator of claim 6.

8. a first resin provided between the first coil and the insulator and covering the first coil; a second resin provided between the second coil and the insulator and covering the second coil; a third resin provided between the third coil and the insulator and covering the third coil; a fourth resin provided between the fourth coil and the insulator and covering the fourth coil; Further comprising: The isolator of claim 1 .

9. the first wiring board, the second wiring board, and the third wiring board are flexible printed wiring boards; The isolator of claim 1 .

10. a first semiconductor chip; a second semiconductor chip; a first wiring board having the first semiconductor chip provided on a first surface facing a first direction; a second wiring board having the second semiconductor chip provided on a second surface facing the first direction and spaced apart from the first wiring board in a second direction intersecting the first direction; a third wiring board spaced apart from each of the first wiring board and the second wiring board in the first direction; a first coil provided on the first surface of the first wiring board and electrically connected to the first semiconductor chip; a second coil provided on the second surface of the second wiring board and electrically connected to the second semiconductor chip; a third coil provided on a third surface of the third wiring board facing the first surface of the first wiring board and the second surface of the second wiring board, the third coil facing the first coil; a fourth coil provided on the third surface of the third wiring board, facing the second coil, and electrically connected to the third coil; insulators provided between the first wiring board and the second wiring board, between the first wiring board and the third wiring board, and between the second wiring board and the third wiring board; Equipped with Isolator.

Images